Mercurial > hg > octave-max

--- a/NEWS
+++ b/NEWS
@@ -4,9 +4,27 @@
  ** The PCRE library is now required to build Octave.

  ** Octave now features a profiler, thanks to the work of Daniel Kraft
-    under the Google Summer of Code mentorship program. The manual has
+    under the Google Summer of Code mentorship program.  The manual has
     been updated to reflect this addition.

+ ** Overhaul of statistical distribution functions
+
+    Functions now return "single" outputs for inputs of class "single".
+
+    75% reduction in memory usage through use of logical indexing.
+
+    Random sample functions now use the same syntax as rand() and accept
+    a comma separated list of dimensions or a dimension vector.
+
+    Functions have been made Matlab-compatible with regard to special
+    cases (probability on boundaries, probabilities for values outside
+    distribution, etc.).  This may cause subtle changes to existing
+    scripts.
+
+    negative binomial function has been extended to real, non-integer inputs.
+    discrete_inv() now returns v(1) for 0 instead of NaN.
+    nbincdf() recoded to use closed form solution with betainc().
+
  ** strread, textscan, and textread have been completely revamped.

     They now support nearly all Matlab functionality including:
@@ -20,7 +38,7 @@
  ** Certain string functions have been modified for greater Matlab compatibility
     and for 15X greater performance when operating on cell array of strings.

-    deblank : Now requires character or cellstr input
+    deblank : Now requires character or cellstr input.
     strtrim : Now requires character or cellstr input.
               No longer trims nulls ("\0") from string for ML compatibility.
     strmatch: Follows documentation precisely and ignores trailing spaces
--- a/doc/interpreter/contrib.txi
+++ b/doc/interpreter/contrib.txi
@@ -6,12 +6,12 @@
 @c under the terms of the GNU General Public License as published by the
 @c Free Software Foundation; either version 3 of the License, or (at
 @c your option) any later version.
-@c
+@c
 @c Octave is distributed in the hope that it will be useful, but WITHOUT
 @c ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 @c FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 @c for more details.
-@c
+@c
 @c You should have received a copy of the GNU General Public License
 @c along with Octave; see the file COPYING.  If not, see
 @c <http://www.gnu.org/licenses/>.
@@ -23,7 +23,7 @@

 This chapter is dedicated to those who wish to contribute code to Octave.

-@menu
+@menu
 * How to Contribute::
 * General Guidelines::
 * Octave Sources (m-files)::
@@ -56,7 +56,7 @@
 @example
 @group
 hg clone http://www.octave.org/hg/octave
-                             # make a local copy of the octave
+                             # make a local copy of the octave
                              # source repository
 cd octave
 # change some sources@dots{}
@@ -71,13 +71,13 @@
 @end example

 You may want to get familiar with Mercurial queues to manage your
-changesets.  Here is a slightly more complex example using Mercurial
+changesets. Here is a slightly more complex example using Mercurial
 queues, where work on two unrelated changesets is done in parallel and
-one of the changesets is updated after discussion on the maintainers mailing
-list:
+one of the changesets is updated after discussion on the maintainers
+mailing list:

 @example
-hg qnew nasty_bug            # create a new patch
+hg qnew nasty_bug            # create a new patch
 # change sources@dots{}
 hg qref                      # save the changes into the patch
 # change even more@dots{}
@@ -89,7 +89,7 @@
 hg qpop                      # undo the application of the patch
                              # and remove the changes from the
                              # source tree
-hg qnew doc_improvements     # create an unrelated patch
+hg qnew doc_improvements     # create an unrelated patch
 # change doc sources@dots{}
 hg qref -m "could not find myfav.m in the doc"
                              # save the changes into the patch
@@ -122,7 +122,7 @@
 ## Octave is free software; you can redistribute it and/or
 ## modify it under the terms of the GNU General Public
 ## License as published by the Free Software Foundation;
-## either version 3 of the License, or (at your option) any
+## either version 3 of the License, or (at your option) any
 ## later version.
 ##
 ## Octave is distributed in the hope that it will be useful,
@@ -136,40 +136,50 @@
 ## see <http://www.gnu.org/licenses/>.
 @end example

-Always include ChangeLog entries in changesets.  After making your
-source changes, record and briefly describe the changes in the nearest
-ChangeLog file upwards in the directory tree.  Use the previous entries
-as a template.  Your entry should contain your name and email, and the
-path to the modified source file relative to the parent directory of the
-ChangeLog file.  If there are more functions in the file, you should
-also include the name of the modified function (in parentheses after
-file path).  Example:
+Always include commit messages in changesets.  After making your source
+changes, record and briefly describe the changes in your commit message.
+You should have previously configured your @file{.hgrc} (or
+@file{Mercurial.ini} on Windows) with your name and email, which will
+get automatically added to your commit message.  Your commit message
+should have a brief one-line explanation of what the commit does.  If you
+are patching a bug, this one-line explanation should mention the bug
+number at the end.  If your change is small and only touches one file,
+this is typically sufficient.  If you are modifying several files or
+several parts of one file, you should enumerate your changes roughly
+following the GNU coding standards on changelogs, like the following
+example:

 @example
 @group
-2010-04-13  David Bateman  <dbateman@@free.fr>
+look for methods before constructors

-	* DLD-FUNCTIONS/regexp.cc (octregexp_list): Handle repeated matches
-	in the list of matches returned by pcre.
+* symtab.cc (symbol_table::fcn_info::fcn_info_rep::find):
+Look for class methods before constructors, contrary to Matlab
+documentation.
+
+* test/ctor-vs-method: New directory of test classes.
+* test/test_ctor_vs_method.m: New file.
+* test/Makefile.am: Include ctor-vs-method/module.mk.
+(FCN_FILES): Include test_ctor_vs_method.m in the list.
 @end group
 @end example

 @noindent
-The ChangeLog entries should describe what is changed, not why.  Any
-explanation of why a change is needed should appear as comments in the
-code, particularly if there is something that might not be obvious to
-someone reading it later.
+In this example, the names of files is mentioned, and in parentheses the
+name of the function in that file that was modified.  There is no need to
+mention the function for m-files that only contain one function.  The
+commit message should describe what is changed, not why.  Any explanation
+of why a change is needed should appear as comments in the code,
+particularly if there is something that might not be obvious to someone
+reading it later.

-When submitting code which addresses a known bug on the Octave bug tracker
-(@url{http://bugs.octave.org}), please add '(bug #XXXXX)' to the ChangeLog
-and Mercurial commit messages.  Example:
+When submitting code which addresses a known bug on the Octave bug
+tracker (@url{http://bugs.octave.org}), please add '(bug #XXXXX)' to the
+first line of the commit messages.  For example:

 @example
 @group
-2011-03-29  Michael Creel  <michael.creel@@uab.es>
-
-	* statistics/base/ols.m: Fix erroneous degrees of freedom when
-	computing the covariance estimator (bug #32892).
+Fix bug for complex input for gradient (bug #34292).
 @end group
 @end example

@@ -208,7 +218,7 @@
 @end example

 @noindent
-but
+but

 @example
   A([1:i-1;i+1:n], XI(:,2:n-1))
@@ -223,7 +233,7 @@
 @code{endswitch}) rather than generic @code{end}.

 Enclose the @code{if}, @code{while}, @code{until} and @code{switch}
-conditions in parentheses, like in C:
+conditions in parentheses, like in C:

 @example
 @group
@@ -267,7 +277,7 @@
 for both function definitions and function calls.

 Recommended indent is 2 spaces.  When indenting, indent the statement
-after control structures (like @code{if}, @code{while}, etc.). If there
+after control structures (like @code{if}, @code{while}, etc.).  If there
 is a compound statement, indent @emph{both} the curly braces and the
 body of the statement (so that the body gets indented by @emph{two}
 indents).  Example:
@@ -286,7 +296,7 @@

 @noindent
 If you have nested @code{if} statements, use extra braces for extra
-clarification.
+clarification.

 Split long expressions in such a way that a continuation line starts
 with an operator rather than identifier.  If the split occurs inside
--- a/run-octave.in
+++ b/run-octave.in
@@ -30,22 +30,19 @@
 top_srcdir='%abs_top_srcdir%'
 builddir='%builddir%'

-d1="$top_srcdir/test"
-d2="$top_srcdir/scripts"
-d3="$builddir/scripts"
-d4="$builddir/src"
+d1="$top_srcdir/scripts"
+d2="$builddir/scripts"
+d3="$builddir/src"

 d1_list=`$FIND "$d1" -type d -a ! \( \( -name private -o -name '@*' \) -a -prune \) -exec echo '{}' ';' | $SED 's/$/:/'`
 d2_list=`$FIND "$d2" -type d -a ! \( \( -name private -o -name '@*' \) -a -prune \) -exec echo '{}' ';' | $SED 's/$/:/'`
 d3_list=`$FIND "$d3" -type d -a ! \( \( -name private -o -name '@*' \) -a -prune \) -exec echo '{}' ';' | $SED 's/$/:/'`
-d4_list=`$FIND "$d4" -type d -a ! \( \( -name private -o -name '@*' \) -a -prune \) -exec echo '{}' ';' | $SED 's/$/:/'`

 d1_path=`echo "$d1_list" | $AWK '{ t = (s $0); s = t; } END { sub (/:$/, "", s); print s; }'`
 d2_path=`echo "$d2_list" | $AWK '{ t = (s $0); s = t; } END { sub (/:$/, "", s); print s; }'`
 d3_path=`echo "$d3_list" | $AWK '{ t = (s $0); s = t; } END { sub (/:$/, "", s); print s; }'`
-d4_path=`echo "$d4_list" | $AWK '{ t = (s $0); s = t; } END { sub (/:$/, "", s); print s; }'`

-LOADPATH="$d1_path:$d2_path:$d3_path:$d4_path"
+LOADPATH="$d1_path:$d2_path:$d3_path"
 IMAGEPATH="$top_srcdir/scripts/image"
 DOCFILE="$builddir/doc/interpreter/doc-cache"
 INFOFILE="$top_srcdir/doc/interpreter/octave.info"
--- a/scripts/general/accumarray.m
+++ b/scripts/general/accumarray.m
@@ -51,7 +51,7 @@
 ## that in the first column counts how many occurrences each number in
 ## the second column has, taken from the vector @var{x}. Note the usage
 ## of @code{unique}  for assigning to all repeated elements of @var{x}
-## the same index (@xref{doc-unique}).
+## the same index (@pxref{doc-unique}).
 ##
 ## @example
 ## @group
--- a/scripts/general/interpn.m
+++ b/scripts/general/interpn.m
@@ -92,7 +92,7 @@
     if (nargs == 2)
       if (ischar (varargin{2}))
         method = varargin{2};
-      elseif (isnumeric (m) && isscalar (m) && round (m) == m)
+      elseif (isnumeric (m) && isscalar (m) && fix (m) == m)
         m = varargin{2};
       else
         print_usage ();
--- a/scripts/image/image.m
+++ b/scripts/image/image.m
@@ -164,6 +164,7 @@
 endfunction

 %!demo
+%! clf
 %! img = 1 ./ hilb (11);
 %! x = -5:5;
 %! y = x;
@@ -186,4 +187,40 @@
 %! set (h, "cdatamapping", "scaled")
 %! title ('image (-x, -y, img)')

+%!demo
+%! clf
+%! g = 0.1:0.1:10;
+%! h = g'*g;
+%! imagesc (g, g, sin (h));
+%! hold on
+%! imagesc (g, g+12, cos (h/2));
+%! axis ([0 10 0 22])
+%! hold off
+%! title ("two consecutive images")

+%!demo
+%! clf
+%! g = 0.1:0.1:10;
+%! h = g'*g;
+%! imagesc (g, g, sin (h));
+%! hold all
+%! plot (g, 11.0 * ones (size (g)))
+%! imagesc (g, g+12, cos (h/2));
+%! axis ([0 10 0 22])
+%! hold off
+%! title ("image, line, image")
+
+%!demo
+%! clf
+%! g = 0.1:0.1:10;
+%! h = g'*g;
+%! plot (g, 10.5 * ones (size (g)))
+%! hold all
+%! imagesc (g, g, sin (h));
+%! plot (g, 11.0 * ones (size (g)))
+%! imagesc (g, g+12, cos (h/2));
+%! plot (g, 11.5 * ones (size (g)))
+%! axis ([0 10 0 22])
+%! hold off
+%! title ("line, image, line, image, line")
+
--- a/scripts/io/strread.m
+++ b/scripts/io/strread.m
@@ -599,7 +599,7 @@
             ## Cast to integer
             ## FIXME: NaNs will be transformed into zeros
             data = int32 (data);
-          end
+          endif
           data(n) = numeric_fill_value;
           if (pad_out)
             data(end+1:num_lines) = numeric_fill_value;
@@ -626,7 +626,7 @@
                 ## Cast to integer
                 ## FIXME: NaNs will be transformed into zeros
                 data = int32 (data);
-              end
+              endif
               varargout{k} = data.';
               k++;
             case "s"
--- a/scripts/linear-algebra/onenormest.m
+++ b/scripts/linear-algebra/onenormest.m
@@ -278,6 +278,7 @@
 ## Only likely to be within a factor of 10.
 %!test
 %!  N = 100;
+%!  rand ('state', 42);  % Initialize to guarantee reproducible results
 %!  A = rand (N);
 %!  [nm1, v1, w1] = onenormest (A);
 %!  [nminf, vinf, winf] = onenormest (A', 6);
--- a/scripts/miscellaneous/bincoeff.m
+++ b/scripts/miscellaneous/bincoeff.m
@@ -68,46 +68,53 @@
     error ("bincoeff: N and K must be of common size or scalars");
   endif

-  sz = size (n);
-  b   = zeros (sz);
+  if (iscomplex (n) || iscomplex (k))
+    error ("bincoeff: N and K must not be complex");
+  endif

-  ind = (! (k >= 0) | (k != real (round (k))) | isnan (n));
-  b(ind) = NaN;
+  b = zeros (size (n));

-  ind = (k == 0);
-  b(ind) = 1;
+  ok = (k >= 0) & (k == fix (k)) & (! isnan (n));
+  b(! ok) = NaN;

-  ind = ((k > 0) & ((n == real (round (n))) & (n < 0)));
-  b(ind) = (-1) .^ k(ind) .* exp (gammaln (abs (n(ind)) + k(ind))
-                                  - gammaln (k(ind) + 1)
-                                  - gammaln (abs (n(ind))));
+  n_int = (n == fix (n));
+  idx = n_int & (n < 0) & ok;
+  b(idx) = (-1) .^ k(idx) .* exp (gammaln (abs (n(idx)) + k(idx))
+                                  - gammaln (k(idx) + 1)
+                                  - gammaln (abs (n(idx))));

-  ind = ((k > 0) & (n >= k));
-  b(ind) = exp (gammaln (n(ind) + 1)
-                - gammaln (k(ind) + 1)
-                - gammaln (n(ind) - k(ind) + 1));
+  idx = (n >= k) & ok;
+  b(idx) = exp (gammaln (n(idx) + 1)
+                - gammaln (k(idx) + 1)
+                - gammaln (n(idx) - k(idx) + 1));

-  ind = ((k > 0) & ((n != real (round (n))) & (n < k)));
-  b(ind) = (1/pi) * exp (gammaln (n(ind) + 1)
-                         - gammaln (k(ind) + 1)
-                         + gammaln (k(ind) - n(ind))
-                         + log (sin (pi * (n(ind) - k(ind) + 1))));
+  idx = (! n_int) & (n < k) & ok;
+  b(idx) = (1/pi) * exp (gammaln (n(idx) + 1)
+                         - gammaln (k(idx) + 1)
+                         + gammaln (k(idx) - n(idx))
+                         + log (sin (pi * (n(idx) - k(idx) + 1))));

   ## Clean up rounding errors.
-  ind = (n == round (n));
-  b(ind) = round (b(ind));
+  b(n_int) = round (b(n_int));

-  ind = (n != round (n));
-  b(ind) = real (b(ind));
+  idx = ! n_int;
+  b(idx) = real (b(idx));

 endfunction

-%!assert(bincoeff(4,2), 6)
-%!assert(bincoeff(2,4), 0)
-%!assert(bincoeff(0.4,2), -.12, 8*eps)
+
+%!assert(bincoeff (4, 2), 6)
+%!assert(bincoeff (2, 4), 0)
+%!assert(bincoeff (-4, 2), 10)
+%!assert(bincoeff (5, 2), 10)
+%!assert(bincoeff (50, 6), 15890700)
+%!assert(bincoeff (0.4, 2), -.12, 8*eps)

-%!assert(bincoeff (5, 2) == 10 && bincoeff (50, 6) == 15890700);
+%!assert(bincoeff ([4 NaN 4], [-1, 2, 2.5]), NaN (1, 3))

+%% Test input validation
 %!error bincoeff ();
+%!error bincoeff (1, 2, 3);
+%!error bincoeff (ones(3),ones(2))
+%!error bincoeff (ones(2),ones(3))

-%!error bincoeff (1, 2, 3);
--- a/scripts/miscellaneous/getappdata.m
+++ b/scripts/miscellaneous/getappdata.m
@@ -40,7 +40,7 @@
         appdata.(name) = [];
       end_try_catch
       val(nh) = {appdata.(name)};
-    end
+    endfor
     if (nh == 1)
       val = val{1};
     endif
--- a/scripts/miscellaneous/module.mk
+++ b/scripts/miscellaneous/module.mk
@@ -50,6 +50,7 @@
   miscellaneous/paren.m \
   miscellaneous/parseparams.m \
   miscellaneous/perl.m \
+  miscellaneous/python.m \
   miscellaneous/rmappdata.m \
   miscellaneous/run.m \
   miscellaneous/semicolon.m \
new file mode 100644
--- /dev/null
+++ b/scripts/miscellaneous/python.m
@@ -0,0 +1,45 @@
+## Copyright (C) 2008-2011 Julian Schnidder
+## Copyright (C) 2011 Carnë Draug <carandraug+dev@gmail.com>
+##
+## This file is part of Octave.
+##
+## Octave is free software; you can redistribute it and/or modify it
+## under the terms of the GNU General Public License as published by
+## the Free Software Foundation; either version 3 of the License, or (at
+## your option) any later version.
+##
+## Octave is distributed in the hope that it will be useful, but
+## WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+## General Public License for more details.
+##
+## You should have received a copy of the GNU General Public License
+## along with Octave; see the file COPYING.  If not, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn  {Function File} {[@var{output}, @var{status}] =} python (@var{scriptfile})
+## @deftypefnx {Function File} {[@var{output}, @var{status}] =} python (@var{scriptfile}, @var{argument1}, @var{argument2}, @dots{})
+## Invoke python script @var{scriptfile} with possibly a list of
+## command line arguments.
+## Returns output in @var{output} and status
+## in @var{status}.
+## @seealso{system}
+## @end deftypefn
+
+function [output, status] = python (scriptfile = "-c ''", varargin)
+
+  ## VARARGIN is intialized to {}(1x0) if no additional arguments are
+  ## supplied, so there is no need to check for it, or provide an
+  ## initial value in the argument list of the function definition.
+
+  if (ischar (scriptfile)
+      && ((nargin != 1 && iscellstr (varargin))
+          || (nargin == 1 && ! isempty (scriptfile))))
+    [status, output] = system (cstrcat ("python ", scriptfile,
+                                        sprintf (" %s", varargin{:})));
+  else
+    error ("python: invalid arguments");
+  endif
+
+endfunction
--- a/scripts/miscellaneous/setappdata.m
+++ b/scripts/miscellaneous/setappdata.m
@@ -33,7 +33,7 @@
   for nh = 1:numel(h)
     if (! isfield (get (h(nh)), "__appdata__"))
       addproperty ("__appdata__", h(nh), "any", struct ());
-    end
+    endif
     appdata = get (h(nh), "__appdata__");
     for narg = 1:2:numel(varargin)
       if (iscellstr (varargin{narg}))
--- a/scripts/optimization/optimset.m
+++ b/scripts/optimization/optimset.m
@@ -39,9 +39,8 @@
       printf ("  %s\n", opts{:});
       puts ("\n");
     else
-      ## Return empty structure.
-      ## We're incompatible with Matlab at this point.
-      retval = struct ();
+      ## Return struct with all options initialized to []
+      retval = cell2struct (repmat ({[]}, size (opts)), opts, 2);
     endif
   elseif (nargs == 1 && ischar (varargin{1}))
     ## Return defaults for named function.
@@ -90,5 +89,9 @@

 endfunction

+
 %!assert (optimget (optimset ('tolx', 1e-2), 'tOLx'), 1e-2)
 %!assert (isfield (optimset ('tolFun', 1e-3), 'TolFun'))
+
+%!error (optimset ("%NOT_A_REAL_FUNCTION_NAME%"))
+
--- a/scripts/plot/axis.m
+++ b/scripts/plot/axis.m
@@ -321,7 +321,7 @@
     scale = get (ca, strcat (ax, "scale"));
     if (strcmp (scale, "log") && any (data > 0))
       data(data<=0) = NaN;
-    end
+    endif
     if (iscell (data))
       data = data (find (! cellfun ("isempty", data)));
       if (! isempty (data))
@@ -350,6 +350,7 @@
 endfunction

 %!demo
+%! clf
 %! t=0:0.01:2*pi; x=sin(t);
 %!
 %! subplot(221);
@@ -372,6 +373,7 @@
 %! axis("normal");

 %!demo
+%! clf
 %! t=0:0.01:2*pi; x=sin(t);
 %!
 %! subplot(121);
@@ -385,6 +387,7 @@
 %! axis("xy");

 %!demo
+%! clf
 %! t=0:0.01:2*pi; x=sin(t);
 %!
 %! subplot(331);
@@ -433,6 +436,7 @@
 %! axis("on");

 %!demo
+%! clf
 %! t=0:0.01:2*pi; x=sin(t);
 %!
 %! subplot(321);
@@ -493,3 +497,8 @@
 %! legend ({"x >= 1", "x <= 1"}, "location", "north")
 %! title ("ylim = [1, 10]")

+%!demo
+%! clf
+%! loglog (1:20, "-s")
+%! axis tight
+
--- a/scripts/plot/contour.m
+++ b/scripts/plot/contour.m
@@ -71,11 +71,22 @@
 endfunction

 %!demo
+%! clf ()
 %! [x, y, z] = peaks ();
 %! contour (x, y, z);

 %!demo
+%! clf ()
 %! [theta, r] = meshgrid (linspace (0, 2*pi, 64), linspace(0,1,64));
 %! [X, Y] = pol2cart (theta, r);
 %! Z = sin(2*theta).*(1-r);
 %! contour(X, Y, abs(Z), 10)
+
+%!demo
+%! clf ()
+%! x = linspace (-2, 2);
+%! [x, y] = meshgrid (x);
+%! z = sqrt (x.^2 + y.^2) ./ (x.^2 + y.^2+1);
+%! contourf (x, y, z, [0.4, 0.4])
+%! title ("The hole should be filled with the background color")
+
--- a/scripts/plot/private/__contour__.m
+++ b/scripts/plot/private/__contour__.m
@@ -319,10 +319,18 @@
       else
         ## Special case unclosed contours
       endif
+      if (isnan(cont_lev(idx)))
+        fc = get (ca, "color");
+        if (strcmp (fc, "none"))
+          fc = get (ancestor (ca, "figure"), "color");
+        endif
+      else
+        fc = "flat";
+      endif
       h = [h; __go_patch__(ca, "xdata", ctmp(1, :)(:), "ydata", ctmp(2, :)(:),
                            "vertices", ctmp.', "faces", 1:(cont_len(idx)-1),
                            "facevertexcdata", cont_lev(idx),
-                           "facecolor", "flat", "cdata", cont_lev(idx),
+                           "facecolor", fc, "cdata", cont_lev(idx),
                            "edgecolor", lc, "linestyle", ls,
                            "linewidth", lw, "parent", hg)];
     endfor
--- a/scripts/plot/private/__go_draw_axes__.m
+++ b/scripts/plot/private/__go_draw_axes__.m
@@ -386,7 +386,7 @@
       ytick = axis_obj.ytick
       yticklabel = axis_obj.yticklabel
       yticklabelmode = axis_obj.yticklabelmode
-    end
+    endif

     xlim = axis_obj.xlim;
     ylim = axis_obj.ylim;
@@ -1583,6 +1583,13 @@
         fprintf (plot_stream, "%s \"-\" %s %s %s \\\n", plot_cmd,
                  usingclause{1}, titlespec{1}, withclause{1});
       elseif (is_image_data (1))
+        if (numel (is_image_data) > 1 && is_image_data(2))
+          ## Remove terminating semicolon
+          n = max (strfind (withclause{1}, ";"));
+          if (! isempty(n))
+            withclause{1} = withclause{1}(1:n-1);
+          endif
+        endif
         fprintf (plot_stream, "%s \"-\" %s %s %s \\\n", plot_cmd,
                  usingclause{1}, titlespec{1}, withclause{1});
       else
@@ -1604,9 +1611,20 @@
               fputs (plot_stream, "unset obj 2; \\\n");
               fg_is_set = false;
             endif
+            if (numel (is_image_data) > i && is_image_data(i+1))
+              ## Remove terminating semicolon
+              n = max (strfind (withclause{i}, ";"));
+              if (! isempty(n))
+                withclause{i} = withclause{i}(1:n-1);
+              endif
+            endif
+            fprintf (plot_stream, "%s \"-\" %s %s %s \\\n", plot_cmd,
+                     usingclause{i}, titlespec{i}, withclause{i});
+          else
+            ## For consecutive images continue with the same plot command
+            fprintf (plot_stream, "%s \"-\" %s %s %s \\\n", ",",
+                     usingclause{i}, titlespec{i}, withclause{i});
           endif
-          fprintf (plot_stream, "%s \"-\" %s %s %s \\\n", plot_cmd,
-                   usingclause{i}, titlespec{i}, withclause{i});
         elseif (is_image_data (i-1))
           if (bg_is_set)
             fputs (plot_stream, "unset obj 1; \\\n");
@@ -1973,61 +1991,67 @@
     do_tics_1 (obj.xtickmode, obj.xtick, obj.xminortick, obj.xticklabelmode,
                obj.xticklabel, obj.xcolor, "x2", plot_stream, true, mono,
                "border", obj.tickdir, ticklength, fontname, fontspec,
-               obj.interpreter, obj.xscale);
+               obj.interpreter, obj.xscale, gnuplot_term);
     do_tics_1 ("manual", [], "off", obj.xticklabelmode, obj.xticklabel,
                obj.xcolor, "x", plot_stream, true, mono, "border",
-               "", "", fontname, fontspec, obj.interpreter, obj.xscale);
+               "", "", fontname, fontspec, obj.interpreter, obj.xscale,
+               gnuplot_term);
   elseif (strcmpi (obj.xaxislocation, "zero"))
     do_tics_1 (obj.xtickmode, obj.xtick, obj.xminortick, obj.xticklabelmode,
                obj.xticklabel, obj.xcolor, "x", plot_stream, true, mono,
                "axis", obj.tickdir, ticklength, fontname, fontspec,
-               obj.interpreter, obj.xscale);
+               obj.interpreter, obj.xscale, gnuplot_term);
     do_tics_1 ("manual", [], "off", obj.xticklabelmode, obj.xticklabel,
                obj.xcolor, "x2", plot_stream, true, mono, "axis",
-               "", "", fontname, fontspec, obj.interpreter, obj.xscale);
+               "", "", fontname, fontspec, obj.interpreter, obj.xscale,
+               gnuplot_term);
   else
     do_tics_1 (obj.xtickmode, obj.xtick, obj.xminortick, obj.xticklabelmode,
                obj.xticklabel, obj.xcolor, "x", plot_stream, true, mono,
                "border", obj.tickdir, ticklength, fontname, fontspec,
-               obj.interpreter, obj.xscale);
+               obj.interpreter, obj.xscale, gnuplot_term);
     do_tics_1 ("manual", [], "off", obj.xticklabelmode, obj.xticklabel,
                obj.xcolor, "x2", plot_stream, true, mono, "border",
-               "", "", fontname, fontspec, obj.interpreter, obj.xscale);
+               "", "", fontname, fontspec, obj.interpreter, obj.xscale,
+               gnuplot_term);
   endif
   if (strcmpi (obj.yaxislocation, "right"))
     do_tics_1 (obj.ytickmode, obj.ytick, obj.yminortick, obj.yticklabelmode,
                obj.yticklabel, obj.ycolor, "y2", plot_stream, ymirror, mono,
                "border", obj.tickdir, ticklength, fontname, fontspec,
-               obj.interpreter, obj.yscale);
+               obj.interpreter, obj.yscale, gnuplot_term);
     do_tics_1 ("manual", [], "off", obj.yticklabelmode, obj.yticklabel,
                obj.ycolor, "y", plot_stream, ymirror, mono, "border",
-               "", "", fontname, fontspec, obj.interpreter, obj.yscale);
+               "", "", fontname, fontspec, obj.interpreter, obj.yscale,
+               gnuplot_term);
   elseif (strcmpi (obj.yaxislocation, "zero"))
     do_tics_1 (obj.ytickmode, obj.ytick, obj.yminortick, obj.yticklabelmode,
                obj.yticklabel, obj.ycolor, "y", plot_stream, ymirror, mono,
                "axis", obj.tickdir, ticklength, fontname, fontspec,
-               obj.interpreter, obj.yscale);
+               obj.interpreter, obj.yscale, gnuplot_term);
     do_tics_1 ("manual", [], "off", obj.yticklabelmode, obj.yticklabel,
                obj.ycolor, "y2", plot_stream, ymirror, mono, "axis",
-               "", "", fontname, fontspec, obj.interpreter, obj.yscale);
+               "", "", fontname, fontspec, obj.interpreter, obj.yscale,
+               gnuplot_term);
   else
     do_tics_1 (obj.ytickmode, obj.ytick, obj.yminortick, obj.yticklabelmode,
                obj.yticklabel, obj.ycolor, "y", plot_stream, ymirror, mono,
                "border", obj.tickdir, ticklength, fontname, fontspec,
-               obj.interpreter, obj.yscale);
+               obj.interpreter, obj.yscale, gnuplot_term);
     do_tics_1 ("manual", [], "off", obj.yticklabelmode, obj.yticklabel,
                obj.ycolor, "y2", plot_stream, ymirror, mono, "border",
-               "", "", fontname, fontspec, obj.interpreter, obj.yscale);
+               "", "", fontname, fontspec, obj.interpreter, obj.yscale,
+               gnuplot_term);
   endif
   do_tics_1 (obj.ztickmode, obj.ztick, obj.zminortick, obj.zticklabelmode,
              obj.zticklabel, obj.zcolor, "z", plot_stream, true, mono,
              "border", obj.tickdir, ticklength, fontname, fontspec,
-             obj.interpreter, obj.zscale);
+             obj.interpreter, obj.zscale, gnuplot_term);
 endfunction

 function do_tics_1 (ticmode, tics, mtics, labelmode, labels, color, ax,
                     plot_stream, mirror, mono, axispos, tickdir, ticklength,
-                    fontname, fontspec, interpreter, scale)
+                    fontname, fontspec, interpreter, scale, gnuplot_term)
   persistent warned_latex = false;
   if (strcmpi (interpreter, "tex"))
     for n = 1 : numel(labels)
@@ -2040,8 +2064,12 @@
     endif
   endif
   if (strcmp (scale, "log"))
-    fmt = "10^{%T}";
     num_mtics = 10;
+    if (any (strcmp (gnuplot_term, {"tikz", "pstex", "pslatex", "epslatex"})))
+      fmt = "$10^{%T}$";
+    else
+      fmt = "10^{%T}";
+    endif
   else
     fmt = "%g";
     num_mtics = 5;
--- a/scripts/polynomial/ppval.m
+++ b/scripts/polynomial/ppval.m
@@ -69,7 +69,7 @@
     Pidx = reshape (Pidx, [sxi, k, d]);
     Pidx = shiftdim (Pidx, length (sxi));
     dimvec = [d, sxi];
-  end
+  endif
   ndv = length (dimvec);

   ## Offsets.
--- a/scripts/sparse/gmres.m
+++ b/scripts/sparse/gmres.m
@@ -69,7 +69,7 @@

   if (nargin < 2 || nargin > 8)
     print_usage ();
-  end
+  endif

   if (ischar (A))
     Ax = str2func (A);
--- a/scripts/statistics/distributions/betacdf.m
+++ b/scripts/statistics/distributions/betacdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,9 +19,9 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} betacdf (@var{x}, @var{a}, @var{b})
-## For each element of @var{x}, returns the CDF at @var{x} of the beta
-## distribution with parameters @var{a} and @var{b}, i.e.,
-## PROB (beta (@var{a}, @var{b}) @leq{} @var{x}).
+## For each element of @var{x}, compute the cumulative distribution function
+## (CDF) at @var{x} of the Beta distribution with parameters @var{a} and
+## @var{b}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -32,33 +33,61 @@
     print_usage ();
   endif

-  if (!isscalar (a) || !isscalar(b))
+  if (!isscalar (a) || !isscalar (b))
     [retval, x, a, b] = common_size (x, a, b);
     if (retval > 0)
-      error ("betacdf: X, A and B must be of common size or scalar");
+      error ("betacdf: X, A, and B must be of common size or scalars");
     endif
   endif

-  sz = size(x);
-  cdf = zeros (sz);
+  if (iscomplex (x) || iscomplex (a) || iscomplex (b))
+    error ("betacdf: X, A, and B must not be complex");
+  endif

-  k = find (!(a > 0) | !(b > 0) | isnan (x));
-  if (any (k))
-    cdf (k) = NaN;
+  if (isa (x, "single") || isa (a, "single") || isa (b, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x >= 1) & (a > 0) & (b > 0));
-  if (any (k))
-    cdf (k) = 1;
-  endif
+  k = isnan (x) | !(a > 0) | !(b > 0);
+  cdf(k) = NaN;
+
+  k = (x >= 1) & (a > 0) & (b > 0);
+  cdf(k) = 1;

-  k = find ((x > 0) & (x < 1) & (a > 0) & (b > 0));
-  if (any (k))
-    if (isscalar (a) && isscalar(b))
-      cdf (k) = betainc (x(k), a, b);
-    else
-      cdf (k) = betainc (x(k), a(k), b(k));
-    endif
+  k = (x > 0) & (x < 1) & (a > 0) & (b > 0);
+  if (isscalar (a) && isscalar (b))
+    cdf(k) = betainc (x(k), a, b);
+  else
+    cdf(k) = betainc (x(k), a(k), b(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2];
+%! y = [0 0 0.75 1 1];
+%!assert(betacdf (x, ones(1,5), 2*ones(1,5)), y);
+%!assert(betacdf (x, 1, 2*ones(1,5)), y);
+%!assert(betacdf (x, ones(1,5), 2), y);
+%!assert(betacdf (x, [0 1 NaN 1 1], 2), [NaN 0 NaN 1 1]);
+%!assert(betacdf (x, 1, 2*[0 1 NaN 1 1]), [NaN 0 NaN 1 1]);
+%!assert(betacdf ([x(1:2) NaN x(4:5)], 1, 2), [y(1:2) NaN y(4:5)]);
+
+%% Test class of input preserved
+%!assert(betacdf ([x, NaN], 1, 2), [y, NaN]);
+%!assert(betacdf (single([x, NaN]), 1, 2), single([y, NaN]));
+%!assert(betacdf ([x, NaN], single(1), 2), single([y, NaN]));
+%!assert(betacdf ([x, NaN], 1, single(2)), single([y, NaN]));
+
+%% Test input validation
+%!error betacdf ()
+%!error betacdf (1)
+%!error betacdf (1,2)
+%!error betacdf (1,2,3,4)
+%!error betacdf (ones(3),ones(2),ones(2))
+%!error betacdf (ones(2),ones(3),ones(2))
+%!error betacdf (ones(2),ones(2),ones(3))
+
--- a/scripts/statistics/distributions/betainv.m
+++ b/scripts/statistics/distributions/betainv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,7 +19,7 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} betainv (@var{x}, @var{a}, @var{b})
-## For each component of @var{x}, compute the quantile (the inverse of
+## For each element of @var{x}, compute the quantile (the inverse of
 ## the CDF) at @var{x} of the Beta distribution with parameters @var{a}
 ## and @var{b}.
 ## @end deftypefn
@@ -32,36 +33,39 @@
     print_usage ();
   endif

-  if (!isscalar (a) || !isscalar(b))
+  if (!isscalar (a) || !isscalar (b))
     [retval, x, a, b] = common_size (x, a, b);
     if (retval > 0)
-      error ("betainv: X, A and B must be of common size or scalars");
+      error ("betainv: X, A, and B must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  inv = zeros (sz);
-
-  k = find ((x < 0) | (x > 1) | !(a > 0) | !(b > 0) | isnan (x));
-  if (any (k))
-    inv (k) = NaN;
+  if (iscomplex (x) || iscomplex (a) || iscomplex (b))
+    error ("betainv: X, A, and B must not be complex");
   endif

-  k = find ((x == 1) & (a > 0) & (b > 0));
-  if (any (k))
-    inv (k) = 1;
+  if (isa (x, "single") || isa (a, "single") || isa (b, "single"))
+    inv = zeros (size (x), "single");
+  else
+    inv = zeros (size (x));
   endif

+  k = (x < 0) | (x > 1) | !(a > 0) | !(b > 0) | isnan (x);
+  inv(k) = NaN;
+
+  k = (x == 1) & (a > 0) & (b > 0);
+  inv(k) = 1;
+
   k = find ((x > 0) & (x < 1) & (a > 0) & (b > 0));
   if (any (k))
-    if (!isscalar(a) || !isscalar(b))
-      a = a (k);
-      b = b (k);
+    if (!isscalar (a) || !isscalar (b))
+      a = a(k);
+      b = b(k);
       y = a ./ (a + b);
     else
       y = a / (a + b) * ones (size (k));
     endif
-    x = x (k);
+    x = x(k);

     if (isa (y, "single"))
       myeps = eps ("single");
@@ -97,7 +101,36 @@
       y_old = y_new;
     endfor

-    inv (k) = y_new;
+    inv(k) = y_new;
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.75 1 2];
+%!assert(betainv (x, ones(1,5), 2*ones(1,5)), [NaN 0 0.5 1 NaN]);
+%!assert(betainv (x, 1, 2*ones(1,5)), [NaN 0 0.5 1 NaN]);
+%!assert(betainv (x, ones(1,5), 2), [NaN 0 0.5 1 NaN]);
+%!assert(betainv (x, [1 0 NaN 1 1], 2), [NaN NaN NaN 1 NaN]);
+%!assert(betainv (x, 1, 2*[1 0 NaN 1 1]), [NaN NaN NaN 1 NaN]);
+%!assert(betainv ([x(1:2) NaN x(4:5)], 1, 2), [NaN 0 NaN 1 NaN]);
+
+%% Test class of input preserved
+%!assert(betainv ([x, NaN], 1, 2), [NaN 0 0.5 1 NaN NaN]);
+%!assert(betainv (single([x, NaN]), 1, 2), single([NaN 0 0.5 1 NaN NaN]));
+%!assert(betainv ([x, NaN], single(1), 2), single([NaN 0 0.5 1 NaN NaN]));
+%!assert(betainv ([x, NaN], 1, single(2)), single([NaN 0 0.5 1 NaN NaN]));
+
+%% Test input validation
+%!error betainv ()
+%!error betainv (1)
+%!error betainv (1,2)
+%!error betainv (1,2,3,4)
+%!error betainv (ones(3),ones(2),ones(2))
+%!error betainv (ones(2),ones(3),ones(2))
+%!error betainv (ones(2),ones(2),ones(3))
+%!error betainv (i, 2, 2)
+%!error betainv (2, i, 2)
+%!error betainv (2, 2, i)
+
--- a/scripts/statistics/distributions/betapdf.m
+++ b/scripts/statistics/distributions/betapdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ## Copyright (C) 2010 Christos Dimitrakakis
 ##
@@ -19,8 +20,8 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} betapdf (@var{x}, @var{a}, @var{b})
-## For each element of @var{x}, returns the PDF at @var{x} of the beta
-## distribution with parameters @var{a} and @var{b}.
+## For each element of @var{x}, compute the probability density function (PDF)
+## at @var{x} of the Beta distribution with parameters @var{a} and @var{b}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>, CD <christos.dimitrakakis@gmail.com>
@@ -32,70 +33,98 @@
     print_usage ();
   endif

-  if (!isscalar (a) || !isscalar(b))
+  if (!isscalar (a) || !isscalar (b))
     [retval, x, a, b] = common_size (x, a, b);
     if (retval > 0)
-      error ("betapdf: X, A and B must be of common size or scalar");
+      error ("betapdf: X, A, and B must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  pdf = zeros (sz);
+  if (iscomplex (x) || iscomplex (a) || iscomplex (b))
+    error ("betapdf: X, A, and B must not be complex");
+  endif

-  k = find (!(a > 0) | !(b > 0) | isnan (x));
-  if (any (k))
-    pdf (k) = NaN;
+  if (isa (x, "single") || isa (a, "single") || isa (b, "single"));
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
   endif

-  k = find ((x > 0) & (x < 1) & (a > 0) & (b > 0) & ((a != 1) | (b != 1)));
-  if (any (k))
-    if (isscalar(a) && isscalar(b))
-      pdf(k) = exp ((a - 1) .* log (x(k))
-                            + (b - 1) .* log (1 - x(k))
-                    + lgamma(a + b) - lgamma(a) - lgamma(b));
-    else
-      pdf(k) = exp ((a(k) - 1) .* log (x(k))
-                            + (b(k) - 1) .* log (1 - x(k))
-                    + lgamma(a(k) + b(k)) - lgamma(a(k)) - lgamma(b(k)));
-    endif
+  k = !(a > 0) | !(b > 0) | isnan (x);
+  pdf(k) = NaN;
+
+  k = (x > 0) & (x < 1) & (a > 0) & (b > 0) & ((a != 1) | (b != 1));
+  if (isscalar (a) && isscalar (b))
+    pdf(k) = exp ((a - 1) * log (x(k))
+                  + (b - 1) * log (1 - x(k))
+                  + lgamma (a + b) - lgamma (a) - lgamma (b));
+  else
+    pdf(k) = exp ((a(k) - 1) .* log (x(k))
+                  + (b(k) - 1) .* log (1 - x(k))
+                  + lgamma (a(k) + b(k)) - lgamma (a(k)) - lgamma (b(k)));
   endif

   ## Most important special cases when the density is finite.
-  k = find ((x == 0) & (a == 1) & (b > 0) & (b != 1));
-  if (any (k))
-    if (isscalar(a) && isscalar(b))
-      pdf(k) = exp(lgamma(a + b) - lgamma(a) - lgamma(b));
-    else
-      pdf(k) = exp(lgamma(a(k) + b(k)) - lgamma(a(k)) - lgamma(b(k)));
-    endif
+  k = (x == 0) & (a == 1) & (b > 0) & (b != 1);
+  if (isscalar (a) && isscalar (b))
+    pdf(k) = exp (lgamma (a + b) - lgamma (a) - lgamma (b));
+  else
+    pdf(k) = exp (lgamma (a(k) + b(k)) - lgamma (a(k)) - lgamma (b(k)));
   endif

-  k = find ((x == 1) & (b == 1) & (a > 0) & (a != 1));
-  if (any (k))
-    if (isscalar(a) && isscalar(b))
-      pdf(k) = exp(lgamma(a + b) - lgamma(a) - lgamma(b));
-    else
-      pdf(k) = exp(lgamma(a(k) + b(k)) - lgamma(a(k)) - lgamma(b(k)));
-    endif
+  k = (x == 1) & (b == 1) & (a > 0) & (a != 1);
+  if (isscalar (a) && isscalar (b))
+    pdf(k) = exp (lgamma (a + b) - lgamma (a) - lgamma (b));
+  else
+    pdf(k) = exp (lgamma (a(k) + b(k)) - lgamma (a(k)) - lgamma (b(k)));
   endif

-  k = find ((x >= 0) & (x <= 1) & (a == 1) & (b == 1));
-  if (any (k))
-    pdf(k) = 1;
-  endif
+  k = (x >= 0) & (x <= 1) & (a == 1) & (b == 1);
+  pdf(k) = 1;

   ## Other special case when the density at the boundary is infinite.
-  k = find ((x == 0) & (a < 1));
-  if (any (k))
-    pdf(k) = Inf;
-  endif
+  k = (x == 0) & (a < 1);
+  pdf(k) = Inf;

-  k = find ((x == 1) & (b < 1));
-  if (any (k))
-    pdf(k) = Inf;
-  endif
+  k = (x == 1) & (b < 1);
+  pdf(k) = Inf;

 endfunction

-%% Test large values for betapdf
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2];
+%! y = [0 2 1 0 0];
+%!assert(betapdf (x, ones(1,5), 2*ones(1,5)), y);
+%!assert(betapdf (x, 1, 2*ones(1,5)), y);
+%!assert(betapdf (x, ones(1,5), 2), y);
+%!assert(betapdf (x, [0 NaN 1 1 1], 2), [NaN NaN y(3:5)]);
+%!assert(betapdf (x, 1, 2*[0 NaN 1 1 1]), [NaN NaN y(3:5)]);
+%!assert(betapdf ([x, NaN], 1, 2), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(betapdf (single([x, NaN]), 1, 2), single([y, NaN]));
+%!assert(betapdf ([x, NaN], single(1), 2), single([y, NaN]));
+%!assert(betapdf ([x, NaN], 1, single(2)), single([y, NaN]));
+
+%% Beta (1/2,1/2) == arcsine distribution
+%!test
+%! x = rand (10,1);
+%! y = 1./(pi * sqrt (x.*(1-x)));
+%! assert(betapdf (x, 1/2, 1/2), y, 50*eps);
+
+%% Test large input values to betapdf
 %!assert (betapdf(0.5, 1000, 1000), 35.678, 1e-3)
+
+%% Test input validation
+%!error betapdf ()
+%!error betapdf (1)
+%!error betapdf (1,2)
+%!error betapdf (1,2,3,4)
+%!error betapdf (ones(3),ones(2),ones(2))
+%!error betapdf (ones(2),ones(3),ones(2))
+%!error betapdf (ones(2),ones(2),ones(3))
+%!error betapdf (i, 2, 2)
+%!error betapdf (2, i, 2)
+%!error betapdf (2, 2, i)
+
--- a/scripts/statistics/distributions/betarnd.m
+++ b/scripts/statistics/distributions/betarnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,83 +18,120 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} betarnd (@var{a}, @var{b}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} betarnd (@var{a}, @var{b}, @var{sz})
-## Return an @var{r} by @var{c} or @code{size (@var{sz})} matrix of
-## random samples from the Beta distribution with parameters @var{a} and
-## @var{b}.  Both @var{a} and @var{b} must be scalar or of size @var{r}
-##  by @var{c}.
+## @deftypefn  {Function File} {} betarnd (@var{a}, @var{b})
+## @deftypefnx {Function File} {} betarnd (@var{a}, @var{b}, @var{r})
+## @deftypefnx {Function File} {} betarnd (@var{a}, @var{b}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} betarnd (@var{a}, @var{b}, [@var{sz}])
+## Return a matrix of random samples from the Beta distribution with parameters
+## @var{a} and @var{b}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{a} and @var{b}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{a} and @var{b}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the Beta distribution

-function rnd = betarnd (a, b, r, c)
+function rnd = betarnd (a, b, varargin)

-  if (nargin > 1)
-    if (!isscalar(a) || !isscalar(b))
-      [retval, a, b] = common_size (a, b);
-      if (retval > 0)
-        error ("betarnd: A and B must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (a) || !isscalar (b))
+    [retval, a, b] = common_size (a, b);
+    if (retval > 0)
+      error ("betarnd: A and B must be of common size or scalars");
     endif
   endif

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("betarnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("betarnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+  if (iscomplex (a) || iscomplex (b))
+    error ("betarnd: A and B must not be complex");
+  endif

-    if (any (size (a) != 1)
-        && (length (size (a)) != length (sz) || any (size (a) != sz)))
-      error ("betarnd: A and B must be scalar or of size [R,C]");
-    endif
+  if (nargin == 2)
+    sz = size (a);
   elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      error ("betarnd: R must be a positive integer or vector");
+      error ("betarnd: dimension vector must be row vector of non-negative integers");
     endif
-
-    if (any (size (a) != 1)
-        && (length (size (a)) != length (sz) || any (size (a) != sz)))
-      error ("betarnd: A and B must be scalar or of size SZ");
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("betarnd: dimensions must be non-negative integers");
     endif
-  elseif (nargin == 2)
-    sz = size(a);
-  else
-    print_usage ();
+    sz = [varargin{:}];
   endif

-  if (isscalar(a) && isscalar(b))
-    if (find (!(a > 0) | !(a < Inf) | !(b > 0) | !(b < Inf)))
-      rnd = NaN (sz);
+  if (!isscalar (a) && !isequal (size (a), sz))
+    error ("betarnd: A and B must be scalar or of size SZ");
+  endif
+
+  if (isa (a, "single") || isa (b, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif
+
+  if (isscalar (a) && isscalar (b))
+    if ((a > 0) && (a < Inf) && (b > 0) && (b < Inf))
+      r = randg (a, sz);
+      rnd = r ./ (r + randg (b, sz));
+      if (strcmp (cls, "single"))
+        rnd = single (rnd);
+      endif
     else
-      r1 = randg(a,sz);
-      rnd = r1 ./ (r1 + randg(b,sz));
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = zeros (sz);
+    rnd = NaN (sz, cls);

-    k = find (!(a > 0) | !(a < Inf) | !(b > 0) | !(b < Inf));
-    if (any (k))
-      rnd(k) = NaN (size (k));
-    endif
-
-    k = find ((a > 0) & (a < Inf) & (b > 0) & (b < Inf));
-    if (any (k))
-      r1 = randg(a(k),size(k));
-      rnd(k) = r1 ./ (r1 + randg(b(k),size(k)));
-    endif
+    k = (a > 0) & (a < Inf) & (b > 0) & (b < Inf);
+    r = randg (a(k));
+    rnd(k) = r ./ (r + randg (b(k)));
   endif

 endfunction
+
+
+%!assert(size (betarnd (1,2)), [1, 1]);
+%!assert(size (betarnd (ones(2,1), 2)), [2, 1]);
+%!assert(size (betarnd (ones(2,2), 2)), [2, 2]);
+%!assert(size (betarnd (1, 2*ones(2,1))), [2, 1]);
+%!assert(size (betarnd (1, 2*ones(2,2))), [2, 2]);
+%!assert(size (betarnd (1, 2, 3)), [3, 3]);
+%!assert(size (betarnd (1, 2, [4 1])), [4, 1]);
+%!assert(size (betarnd (1, 2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (betarnd (1, 2)), "double");
+%!assert(class (betarnd (single(1), 2)), "single");
+%!assert(class (betarnd (single([1 1]), 2)), "single");
+%!assert(class (betarnd (1, single(2))), "single");
+%!assert(class (betarnd (1, single([2 2]))), "single");
+
+%% Test input validation
+%!error betarnd ()
+%!error betarnd (1)
+%!error betarnd (ones(3),ones(2))
+%!error betarnd (ones(2),ones(3))
+%!error betarnd (i, 2)
+%!error betarnd (2, i)
+%!error betarnd (1,2, -1)
+%!error betarnd (1,2, ones(2))
+%!error binornd (1,2, [2 -1 2])
+%!error betarnd (1,2, 1, ones(2))
+%!error betarnd (1,2, 1, -1)
+%!error betarnd (ones(2,2), 2, 3)
+%!error betarnd (ones(2,2), 2, [3, 2])
+%!error betarnd (ones(2,2), 2, 2, 3)
+
--- a/scripts/statistics/distributions/binocdf.m
+++ b/scripts/statistics/distributions/binocdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,8 +19,9 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} binocdf (@var{x}, @var{n}, @var{p})
-## For each element of @var{x}, compute the CDF at @var{x} of the
-## binomial distribution with parameters @var{n} and @var{p}.
+## For each element of @var{x}, compute the cumulative distribution function
+## (CDF) at @var{x} of the binomial distribution with parameters @var{n} and
+## @var{p}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -34,34 +36,62 @@
   if (!isscalar (n) || !isscalar (p))
     [retval, x, n, p] = common_size (x, n, p);
     if (retval > 0)
-      error ("binocdf: X, N and P must be of common size or scalar");
+      error ("binocdf: X, N, and P must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  cdf = zeros (sz);
+  if (iscomplex (x) || iscomplex (n) || iscomplex (p))
+    error ("binocdf: X, N, and P must not be complex");
+  endif

-  k = find (isnan (x) | !(n >= 0) | (n != round (n))
-            | !(p >= 0) | !(p <= 1));
-  if (any (k))
-    cdf(k) = NaN;
+  if (isa (x, "single") || isa (n, "single") || isa (p, "single"));
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x >= n) & (n >= 0) & (n == round (n))
-            & (p >= 0) & (p <= 1));
-  if (any (k))
-    cdf(k) = 1;
-  endif
+  k = isnan (x) | !(n >= 0) | (n != fix (n)) | !(p >= 0) | !(p <= 1);
+  cdf(k) = NaN;
+
+  k = (x >= n) & (n >= 0) & (n == fix (n) & (p >= 0) & (p <= 1));
+  cdf(k) = 1;

-  k = find ((x >= 0) & (x < n) & (n == round (n))
-            & (p >= 0) & (p <= 1));
-  if (any (k))
-    tmp = floor (x(k));
-    if (isscalar (n) && isscalar (p))
-      cdf(k) = 1 - betainc (p, tmp + 1, n - tmp);
-    else
-      cdf(k) = 1 - betainc (p(k), tmp + 1, n(k) - tmp);
-    endif
+  k = (x >= 0) & (x < n) & (n == fix (n)) & (p >= 0) & (p <= 1);
+  tmp = floor (x(k));
+  if (isscalar (n) && isscalar (p))
+    cdf(k) = 1 - betainc (p, tmp + 1, n - tmp);
+  else
+    cdf(k) = 1 - betainc (p(k), tmp + 1, n(k) - tmp);
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 2 3];
+%! y = [0 1/4 3/4 1 1];
+%!assert(binocdf (x, 2*ones(1,5), 0.5*ones(1,5)), y);
+%!assert(binocdf (x, 2, 0.5*ones(1,5)), y);
+%!assert(binocdf (x, 2*ones(1,5), 0.5), y);
+%!assert(binocdf (x, 2*[0 -1 NaN 1.1 1], 0.5), [0 NaN NaN NaN 1]);
+%!assert(binocdf (x, 2, 0.5*[0 -1 NaN 3 1]), [0 NaN NaN NaN 1]);
+%!assert(binocdf ([x(1:2) NaN x(4:5)], 2, 0.5), [y(1:2) NaN y(4:5)]);
+
+%% Test class of input preserved
+%!assert(binocdf ([x, NaN], 2, 0.5), [y, NaN]);
+%!assert(binocdf (single([x, NaN]), 2, 0.5), single([y, NaN]));
+%!assert(binocdf ([x, NaN], single(2), 0.5), single([y, NaN]));
+%!assert(binocdf ([x, NaN], 2, single(0.5)), single([y, NaN]));
+
+%% Test input validation
+%!error binocdf ()
+%!error binocdf (1)
+%!error binocdf (1,2)
+%!error binocdf (1,2,3,4)
+%!error binocdf (ones(3),ones(2),ones(2))
+%!error binocdf (ones(2),ones(3),ones(2))
+%!error binocdf (ones(2),ones(2),ones(3))
+%!error binocdf (i, 2, 2)
+%!error binocdf (2, i, 2)
+%!error binocdf (2, 2, i)
+
--- a/scripts/statistics/distributions/binoinv.m
+++ b/scripts/statistics/distributions/binoinv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,8 +19,9 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} binoinv (@var{x}, @var{n}, @var{p})
-## For each element of @var{x}, compute the quantile at @var{x} of the
-## binomial distribution with parameters @var{n} and @var{p}.
+## For each element of @var{x}, compute the quantile (the inverse of
+## the CDF) at @var{x} of the binomial distribution with parameters
+## @var{n} and @var{p}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -34,24 +36,29 @@
   if (!isscalar (n) || !isscalar (p))
     [retval, x, n, p] = common_size (x, n, p);
     if (retval > 0)
-      error ("binoinv: X, N and P must be of common size or scalars");
+      error ("binoinv: X, N, and P must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  inv = zeros (sz);
+  if (iscomplex (x) || iscomplex (n) || iscomplex (p))
+    error ("binoinv: X, N, and P must not be complex");
+  endif

-  k = find (!(x >= 0) | !(x <= 1) | !(n >= 0) | (n != round (n))
-            | !(p >= 0) | !(p <= 1));
-  if (any (k))
-    inv(k) = NaN;
+  if (isa (x, "single") || isa (n, "single") || isa (p, "single"));
+    inv = zeros (size (x), "single");
+  else
+    inv = zeros (size (x));
   endif

-  k = find ((x >= 0) & (x <= 1) & (n >= 0) & (n == round (n))
-            & (p >= 0) & (p <= 1));
+  k = (!(x >= 0) | !(x <= 1) | !(n >= 0) | (n != fix (n)) |
+       !(p >= 0) | !(p <= 1));
+  inv(k) = NaN;
+
+  k = find ((x >= 0) & (x <= 1) & (n >= 0) & (n == fix (n)
+             & (p >= 0) & (p <= 1)));
   if (any (k))
     if (isscalar (n) && isscalar (p))
-      cdf = binopdf (0, n, p) * ones (size(k));
+      cdf = binopdf (0, n, p) * ones (size (k));
       while (any (inv(k) < n))
         m = find (cdf < x(k));
         if (any (m))
@@ -76,3 +83,32 @@
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(binoinv (x, 2*ones(1,5), 0.5*ones(1,5)), [NaN 0 1 2 NaN]);
+%!assert(binoinv (x, 2, 0.5*ones(1,5)), [NaN 0 1 2 NaN]);
+%!assert(binoinv (x, 2*ones(1,5), 0.5), [NaN 0 1 2 NaN]);
+%!assert(binoinv (x, 2*[0 -1 NaN 1.1 1], 0.5), [NaN NaN NaN NaN NaN]);
+%!assert(binoinv (x, 2, 0.5*[0 -1 NaN 3 1]), [NaN NaN NaN NaN NaN]);
+%!assert(binoinv ([x(1:2) NaN x(4:5)], 2, 0.5), [NaN 0 NaN 2 NaN]);
+
+%% Test class of input preserved
+%!assert(binoinv ([x, NaN], 2, 0.5), [NaN 0 1 2 NaN NaN]);
+%!assert(binoinv (single([x, NaN]), 2, 0.5), single([NaN 0 1 2 NaN NaN]));
+%!assert(binoinv ([x, NaN], single(2), 0.5), single([NaN 0 1 2 NaN NaN]));
+%!assert(binoinv ([x, NaN], 2, single(0.5)), single([NaN 0 1 2 NaN NaN]));
+
+%% Test input validation
+%!error binoinv ()
+%!error binoinv (1)
+%!error binoinv (1,2)
+%!error binoinv (1,2,3,4)
+%!error binoinv (ones(3),ones(2),ones(2))
+%!error binoinv (ones(2),ones(3),ones(2))
+%!error binoinv (ones(2),ones(2),ones(3))
+%!error binoinv (i, 2, 2)
+%!error binoinv (2, i, 2)
+%!error binoinv (2, 2, i)
+
--- a/scripts/statistics/distributions/binopdf.m
+++ b/scripts/statistics/distributions/binopdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -35,26 +36,65 @@
   if (! isscalar (n) || ! isscalar (p))
     [retval, x, n, p] = common_size (x, n, p);
     if (retval > 0)
-      error ("binopdf: X, N and P must be of common size or scalar");
+      error ("binopdf: X, N, and P must be of common size or scalars");
     endif
   endif

-  k = ((x >= 0) & (x <= n)
-       & (x == round (x)) & (n == round (n))
-       & (p >= 0) & (p <= 1));
+  if (iscomplex (x) || iscomplex (n) || iscomplex (p))
+    error ("binopdf: X, N, and P must not be complex");
+  endif

-  pdf = zeros (size (x));
+  if (isa (x, "single") || isa (n, "single") || isa (p, "single"));
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
+  endif
+
+  k = (x == fix (x)) & (n == fix (n)) & (n >= 0) & (p >= 0) & (p <= 1);
+
   pdf(! k) = NaN;
-  if (any (k(:)))
-    x = x(k);
-    if (! isscalar (n))
-      n = n(k);
-    endif
-    if (! isscalar (p))
-      p = p(k);
-    endif
-    z = gammaln(n+1) - gammaln(x+1) - gammaln(n-x+1) + x.*log(p) + (n-x).*log(1-p);
-    pdf(k) = exp (z);
+
+  k &= ((x >= 0) & (x <= n));
+  if (isscalar (n) && isscalar (p))
+    pdf(k) = exp (gammaln (n+1) - gammaln (x(k)+1) - gammaln (n-x(k)+1)
+                  + x(k)*log (p) + (n-x(k))*log (1-p));
+  else
+    pdf(k) = exp (gammaln (n(k)+1) - gammaln (x(k)+1) - gammaln (n(k)-x(k)+1)
+                  + x(k).*log (p(k)) + (n(k)-x(k)).*log (1-p(k)));
   endif

 endfunction
+
+
+%!shared x,y,tol
+%! if (ismac ())
+%!   tol = eps ();
+%! else
+%!   tol = 0;
+%! endif
+%! x = [-1 0 1 2 3];
+%! y = [0 1/4 1/2 1/4 0];
+%!assert(binopdf (x, 2*ones(1,5), 0.5*ones(1,5)), y, tol);
+%!assert(binopdf (x, 2, 0.5*ones(1,5)), y, tol);
+%!assert(binopdf (x, 2*ones(1,5), 0.5), y, tol);
+%!assert(binopdf (x, 2*[0 -1 NaN 1.1 1], 0.5), [0 NaN NaN NaN 0]);
+%!assert(binopdf (x, 2, 0.5*[0 -1 NaN 3 1]), [0 NaN NaN NaN 0]);
+%!assert(binopdf ([x, NaN], 2, 0.5), [y, NaN], tol);
+
+%% Test class of input preserved
+%!assert(binopdf (single([x, NaN]), 2, 0.5), single([y, NaN]));
+%!assert(binopdf ([x, NaN], single(2), 0.5), single([y, NaN]));
+%!assert(binopdf ([x, NaN], 2, single(0.5)), single([y, NaN]));
+
+%% Test input validation
+%!error binopdf ()
+%!error binopdf (1)
+%!error binopdf (1,2)
+%!error binopdf (1,2,3,4)
+%!error binopdf (ones(3),ones(2),ones(2))
+%!error binopdf (ones(2),ones(3),ones(2))
+%!error binopdf (ones(2),ones(2),ones(3))
+%!error binopdf (i, 2, 2)
+%!error binopdf (2, i, 2)
+%!error binopdf (2, 2, i)
+
--- a/scripts/statistics/distributions/binornd.m
+++ b/scripts/statistics/distributions/binornd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,96 +18,136 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} binornd (@var{n}, @var{p}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} binornd (@var{n}, @var{p}, @var{sz})
-## Return an @var{r} by @var{c}  or a @code{size (@var{sz})} matrix of
-## random samples from the binomial distribution with parameters @var{n}
-## and @var{p}.  Both @var{n} and @var{p} must be scalar or of size
-## @var{r} by @var{c}.
+## @deftypefn  {Function File} {} binornd (@var{n}, @var{p})
+## @deftypefnx {Function File} {} binornd (@var{n}, @var{p}, @var{r})
+## @deftypefnx {Function File} {} binornd (@var{n}, @var{p}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} binornd (@var{n}, @var{p}, [@var{sz}])
+## Return a matrix of random samples from the binonmial distribution with
+## parameters @var{n} and @var{p}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{n} and @var{p}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{n} and @var{p}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the binomial distribution

-function rnd = binornd (n, p, r, c)
+function rnd = binornd (n, p, varargin)

-  if (nargin > 1)
-    if (!isscalar(n) || !isscalar(p))
-      [retval, n, p] = common_size (n, p);
-      if (retval > 0)
-        error ("binornd: N and P must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (n) || !isscalar (p))
+    [retval, n, p] = common_size (n, p);
+    if (retval > 0)
+      error ("binornd: N and P must be of common size or scalars");
     endif
   endif

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("binornd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("binornd: C must be a positive integer");
-    endif
-    sz = [r, c];
+  if (iscomplex (n) || iscomplex (p))
+    error ("binornd: N and P must not be complex");
+  endif

-    if (any (size (n) != 1)
-        && (length (size (n)) != length (sz) || any (size (n) != sz)))
-      error ("binornd: N and must be scalar or of size [R, C]");
-    endif
+  if (nargin == 2)
+    sz = size (n);
   elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      error ("binornd: R must be a positive integer or vector");
+      error ("binornd: dimension vector must be row vector of non-negative integers");
     endif
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("binornd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif

-    if (any (size (n) != 1)
-        && (length (size (n)) != length (sz) || any (size (n) != sz)))
-      error ("binornd: N and must be scalar or of size SZ");
-    endif
-  elseif (nargin == 2)
-    sz = size(n);
+  if (!isscalar (n) && !isequal (size (n), sz))
+    error ("binornd: N and P must be scalar or of size SZ");
+  endif
+
+  if (isa (n, "single") || isa (p, "single"))
+    cls = "single";
   else
-    print_usage ();
+    cls = "double";
   endif

   if (isscalar (n) && isscalar (p))
-    if (find (!(n >= 0) | !(n < Inf) | !(n == round (n)) |
-              !(p >= 0) | !(p <= 1)))
-      rnd = NaN (sz);
-    elseif (n == 0)
-      rnd = zeros (sz);
-    else
+    if ((n > 0) && (n < Inf) && (n == fix (n)) && (p >= 0) && (p <= 1))
       nel = prod (sz);
       tmp = rand (n, nel);
-      rnd = sum(tmp < ones (n, nel) * p, 1);
-      rnd = reshape(rnd, sz);
+      rnd = sum (tmp < p, 1);
+      rnd = reshape (rnd, sz);
+      if (strcmp (cls, "single"))
+        rnd = single (rnd);
+      endif
+    elseif ((n == 0) && (p >= 0) && (p <= 1))
+      rnd = zeros (sz, cls);
+    else
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = zeros (sz);
+    rnd = zeros (sz, cls);

-    k = find (!(n >= 0) | !(n < Inf) | !(n == round (n)) |
-              !(p >= 0) | !(p <= 1));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
+    k = !(n >= 0) | !(n < Inf) | !(n == fix (n)) | !(p >= 0) | !(p <= 1);
+    rnd(k) = NaN;

-    k = find ((n > 0) & (n < Inf) & (n == round (n)) & (p >= 0) & (p <= 1));
-    if (any (k))
+    k = (n > 0) & (n < Inf) & (n == fix (n)) & (p >= 0) & (p <= 1);
+    if (any (k(:)))
       N = max (n(k));
-      L = length (k);
+      L = sum (k(:));
       tmp = rand (N, L);
-      ind = (1 : N)' * ones (1, L);
-      rnd(k) = sum ((tmp < ones (N, 1) * p(k)(:)') &
-                    (ind <= ones (N, 1) * n(k)(:)'),1);
+      ind = repmat ((1 : N)', 1, L);
+      rnd(k) = sum ((tmp < repmat (p(k)(:)', N, 1)) &
+                    (ind <= repmat (n(k)(:)', N, 1)), 1);
     endif
   endif

 endfunction

-%!assert (binornd(0, 0, 1), 0)
-%!assert (binornd([0, 0], [0, 0], 1, 2), [0, 0])
+
+%!assert (binornd (0, 0, 1), 0)
+%!assert (binornd ([0, 0], [0, 0], 1, 2), [0, 0])
+
+%!assert(size (binornd (2, 1/2)), [1, 1]);
+%!assert(size (binornd (2*ones(2,1), 1/2)), [2, 1]);
+%!assert(size (binornd (2*ones(2,2), 1/2)), [2, 2]);
+%!assert(size (binornd (2, 1/2*ones(2,1))), [2, 1]);
+%!assert(size (binornd (2, 1/2*ones(2,2))), [2, 2]);
+%!assert(size (binornd (2, 1/2, 3)), [3, 3]);
+%!assert(size (binornd (2, 1/2, [4 1])), [4, 1]);
+%!assert(size (binornd (2, 1/2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (binornd (2, 0.5)), "double");
+%!assert(class (binornd (single(2), 0.5)), "single");
+%!assert(class (binornd (single([2 2]), 0.5)), "single");
+%!assert(class (binornd (2, single(0.5))), "single");
+%!assert(class (binornd (2, single([0.5 0.5]))), "single");
+
+%% Test input validation
+%!error binornd ()
+%!error binornd (1)
+%!error binornd (ones(3),ones(2))
+%!error binornd (ones(2),ones(3))
+%!error binornd (i, 2)
+%!error binornd (2, i)
+%!error binornd (1,2, -1)
+%!error binornd (1,2, ones(2))
+%!error binornd (1,2, [2 -1 2])
+%!error binornd (1,2, 1, ones(2))
+%!error binornd (1,2, 1, -1)
+%!error binornd (ones(2,2), 2, 3)
+%!error binornd (ones(2,2), 2, [3, 2])
+%!error binornd (ones(2,2), 2, 2, 3)
+
--- a/scripts/statistics/distributions/cauchy_cdf.m
+++ b/scripts/statistics/distributions/cauchy_cdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,7 +18,8 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} cauchy_cdf (@var{x}, @var{location}, @var{scale})
+## @deftypefn  {Function File} {} cauchy_cdf (@var{x})
+## @deftypefnx {Function File} {} cauchy_cdf (@var{x}, @var{location}, @var{scale})
 ## For each element of @var{x}, compute the cumulative distribution
 ## function (CDF) at @var{x} of the Cauchy distribution with location
 ## parameter @var{location} and scale parameter @var{scale}.  Default
@@ -27,35 +29,63 @@
 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: CDF of the Cauchy distribution

-function cdf = cauchy_cdf (x, location, scale)
+function cdf = cauchy_cdf (x, location = 0, scale = 1)

-  if (! (nargin == 1 || nargin == 3))
+  if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    location = 0;
-    scale = 1;
-  endif
-
   if (!isscalar (location) || !isscalar (scale))
     [retval, x, location, scale] = common_size (x, location, scale);
     if (retval > 0)
-      error ("cauchy_cdf: X, LOCATION and SCALE must be of common size or scalar");
+      error ("cauchy_cdf: X, LOCATION, and SCALE must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  cdf = NaN (sz);
+  if (iscomplex (x) || iscomplex (location) || iscomplex (scale))
+    error ("cauchy_cdf: X, LOCATION, and SCALE must not be complex");
+  endif

-  k = find (ones (sz) & (location > -Inf) & (location < Inf)
-                      & (scale > 0) & (scale < Inf));
-  if (any (k))
-    if (isscalar (location) && isscalar (scale))
-      cdf(k) = 0.5 + atan ((x(k) - location) ./ scale) / pi;
-    else
-      cdf(k) = 0.5 + atan ((x(k) - location(k)) ./ scale(k)) / pi;
-    endif
+  if (isa (x, "single") || isa (location, "single") || isa (scale, "single"));
+    cdf = NaN (size (x), "single");
+  else
+    cdf = NaN (size (x));
+  endif
+
+  k = !isinf (location) & (scale > 0) & (scale < Inf);
+  if (isscalar (location) && isscalar (scale))
+    cdf = 0.5 + atan ((x - location) / scale) / pi;
+  else
+    cdf(k) = 0.5 + atan ((x(k) - location(k)) ./ scale(k)) / pi;
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2];
+%! y = 1/pi * atan ((x-1) / 2) + 1/2;
+%!assert(cauchy_cdf (x, ones(1,5), 2*ones(1,5)), y);
+%!assert(cauchy_cdf (x, 1, 2*ones(1,5)), y);
+%!assert(cauchy_cdf (x, ones(1,5), 2), y);
+%!assert(cauchy_cdf (x, [-Inf 1 NaN 1 Inf], 2), [NaN y(2) NaN y(4) NaN]);
+%!assert(cauchy_cdf (x, 1, 2*[0 1 NaN 1 Inf]), [NaN y(2) NaN y(4) NaN]);
+%!assert(cauchy_cdf ([x(1:2) NaN x(4:5)], 1, 2), [y(1:2) NaN y(4:5)]);
+
+%% Test class of input preserved
+%!assert(cauchy_cdf ([x, NaN], 1, 2), [y, NaN]);
+%!assert(cauchy_cdf (single([x, NaN]), 1, 2), single([y, NaN]), eps("single"));
+%!assert(cauchy_cdf ([x, NaN], single(1), 2), single([y, NaN]), eps("single"));
+%!assert(cauchy_cdf ([x, NaN], 1, single(2)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error cauchy_cdf ()
+%!error cauchy_cdf (1,2)
+%!error cauchy_cdf (1,2,3,4)
+%!error cauchy_cdf (ones(3),ones(2),ones(2))
+%!error cauchy_cdf (ones(2),ones(3),ones(2))
+%!error cauchy_cdf (ones(2),ones(2),ones(3))
+%!error cauchy_cdf (i, 2, 2)
+%!error cauchy_cdf (2, i, 2)
+%!error cauchy_cdf (2, 2, i)
+
--- a/scripts/statistics/distributions/cauchy_inv.m
+++ b/scripts/statistics/distributions/cauchy_inv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,7 +18,8 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} cauchy_inv (@var{x}, @var{location}, @var{scale})
+## @deftypefn  {Function File} {} cauchy_inv (@var{x})
+## @deftypefnx {Function File} {} cauchy_inv (@var{x}, @var{location}, @var{scale})
 ## For each element of @var{x}, compute the quantile (the inverse of the
 ## CDF) at @var{x} of the Cauchy distribution with location parameter
 ## @var{location} and scale parameter @var{scale}.  Default values are
@@ -27,47 +29,70 @@
 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Quantile function of the Cauchy distribution

-function inv = cauchy_inv (x, location, scale)
+function inv = cauchy_inv (x, location = 0, scale = 1)

-  if (! (nargin == 1 || nargin == 3))
+  if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    location = 0;
-    scale = 1;
-  endif
-
   if (!isscalar (location) || !isscalar (scale))
     [retval, x, location, scale] = common_size (x, location, scale);
     if (retval > 0)
-      error ("cauchy_inv: X, LOCATION and SCALE must be of common size or scalar");
+      error ("cauchy_inv: X, LOCATION, and SCALE must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  inv = NaN (sz);
+  if (iscomplex (x) || iscomplex (location) || iscomplex (scale))
+    error ("cauchy_inv: X, LOCATION, and SCALE must not be complex");
+  endif

-  ok = ((location > -Inf) & (location < Inf) &
-       (scale > 0) & (scale < Inf));
-
-  k = find ((x == 0) & ok);
-  if (any (k))
-    inv(k) = -Inf;
+  if (isa (x, "single") || isa (location, "single") || isa (scale, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  k = find ((x > 0) & (x < 1) & ok);
-  if (any (k))
-    if (isscalar (location) && isscalar (scale))
-      inv(k) = location - scale .* cot (pi * x(k));
-    else
-      inv(k) = location(k) - scale(k) .* cot (pi * x(k));
-    endif
-  endif
+  ok = !isinf (location) & (scale > 0) & (scale < Inf);
+
+  k = (x == 0) & ok;
+  inv(k) = -Inf;

-  k = find ((x == 1) & ok);
-  if (any (k))
-    inv(k) = Inf;
+  k = (x == 1) & ok;
+  inv(k) = Inf;
+
+  k = (x > 0) & (x < 1) & ok;
+  if (isscalar (location) && isscalar (scale))
+    inv(k) = location - scale * cot (pi * x(k));
+  else
+    inv(k) = location(k) - scale(k) .* cot (pi * x(k));
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(cauchy_inv (x, ones(1,5), 2*ones(1,5)), [NaN -Inf 1 Inf NaN], eps);
+%!assert(cauchy_inv (x, 1, 2*ones(1,5)), [NaN -Inf 1 Inf NaN], eps);
+%!assert(cauchy_inv (x, ones(1,5), 2), [NaN -Inf 1 Inf NaN], eps);
+%!assert(cauchy_inv (x, [1 -Inf NaN Inf 1], 2), [NaN NaN NaN NaN NaN]);
+%!assert(cauchy_inv (x, 1, 2*[1 0 NaN Inf 1]), [NaN NaN NaN NaN NaN]);
+%!assert(cauchy_inv ([x(1:2) NaN x(4:5)], 1, 2), [NaN -Inf NaN Inf NaN]);
+
+%% Test class of input preserved
+%!assert(cauchy_inv ([x, NaN], 1, 2), [NaN -Inf 1 Inf NaN NaN], eps);
+%!assert(cauchy_inv (single([x, NaN]), 1, 2), single([NaN -Inf 1 Inf NaN NaN]), eps("single"));
+%!assert(cauchy_inv ([x, NaN], single(1), 2), single([NaN -Inf 1 Inf NaN NaN]), eps("single"));
+%!assert(cauchy_inv ([x, NaN], 1, single(2)), single([NaN -Inf 1 Inf NaN NaN]), eps("single"));
+
+%% Test input validation
+%!error cauchy_inv ()
+%!error cauchy_inv (1,2)
+%!error cauchy_inv (1,2,3,4)
+%!error cauchy_inv (ones(3),ones(2),ones(2))
+%!error cauchy_inv (ones(2),ones(3),ones(2))
+%!error cauchy_inv (ones(2),ones(2),ones(3))
+%!error cauchy_inv (i, 2, 2)
+%!error cauchy_inv (2, i, 2)
+%!error cauchy_inv (2, 2, i)
+
--- a/scripts/statistics/distributions/cauchy_pdf.m
+++ b/scripts/statistics/distributions/cauchy_pdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,7 +18,8 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} cauchy_pdf (@var{x}, @var{location}, @var{scale})
+## @deftypefn  {Function File} {} cauchy_pdf (@var{x})
+## @deftypefnx {Function File} {} cauchy_pdf (@var{x}, @var{location}, @var{scale})
 ## For each element of @var{x}, compute the probability density function
 ## (PDF) at @var{x} of the Cauchy distribution with location parameter
 ## @var{location} and scale parameter @var{scale} > 0.  Default values are
@@ -27,37 +29,69 @@
 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: PDF of the Cauchy distribution

-function pdf = cauchy_pdf (x, location, scale)
+function pdf = cauchy_pdf (x, location = 0, scale = 1)

-  if (! (nargin == 1 || nargin == 3))
+  if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    location = 0;
-    scale = 1;
-  endif
-
   if (!isscalar (location) || !isscalar (scale))
     [retval, x, location, scale] = common_size (x, location, scale);
     if (retval > 0)
-      error ("cauchy_pdf: X, LOCATION and SCALE must be of common size or scalar");
+      error ("cauchy_pdf: X, LOCATION, and SCALE must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  pdf = NaN (sz);
+  if (iscomplex (x) || iscomplex (location) || iscomplex (scale))
+    error ("cauchy_pdf: X, LOCATION, and SCALE must not be complex");
+  endif

-  k = find ((x > -Inf) & (x < Inf) & (location > -Inf) &
-            (location < Inf) & (scale > 0) & (scale < Inf));
-  if (any (k))
-    if (isscalar (location) && isscalar (scale))
-      pdf(k) = ((1 ./ (1 + ((x(k) - location) ./ scale) .^ 2))
-                / pi ./ scale);
-    else
-      pdf(k) = ((1 ./ (1 + ((x(k) - location(k)) ./ scale(k)) .^ 2))
-                / pi ./ scale(k));
-    endif
+  if (isa (x, "single") || isa (location, "single") || isa (scale, "single"))
+    pdf = NaN (size (x), "single");
+  else
+    pdf = NaN (size (x));
+  endif
+
+  k = !isinf (location) & (scale > 0) & (scale < Inf);
+  if (isscalar (location) && isscalar (scale))
+    pdf = ((1 ./ (1 + ((x - location) / scale) .^ 2))
+              / pi / scale);
+  else
+    pdf(k) = ((1 ./ (1 + ((x(k) - location(k)) ./ scale(k)) .^ 2))
+              / pi ./ scale(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2];
+%! y = 1/pi * ( 2 ./ ((x-1).^2 + 2^2) );
+%!assert(cauchy_pdf (x, ones(1,5), 2*ones(1,5)), y);
+%!assert(cauchy_pdf (x, 1, 2*ones(1,5)), y);
+%!assert(cauchy_pdf (x, ones(1,5), 2), y);
+%!assert(cauchy_pdf (x, [-Inf 1 NaN 1 Inf], 2), [NaN y(2) NaN y(4) NaN]);
+%!assert(cauchy_pdf (x, 1, 2*[0 1 NaN 1 Inf]), [NaN y(2) NaN y(4) NaN]);
+%!assert(cauchy_pdf ([x, NaN], 1, 2), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(cauchy_pdf (single([x, NaN]), 1, 2), single([y, NaN]), eps("single"));
+%!assert(cauchy_pdf ([x, NaN], single(1), 2), single([y, NaN]), eps("single"));
+%!assert(cauchy_pdf ([x, NaN], 1, single(2)), single([y, NaN]), eps("single"));
+
+%% Cauchy (0,1) == Student's T distribution with 1 DOF
+%!test
+%! x = rand (10, 1);
+%! assert(cauchy_pdf (x, 0, 1), tpdf (x, 1), eps);
+
+%% Test input validation
+%!error cauchy_pdf ()
+%!error cauchy_pdf (1,2)
+%!error cauchy_pdf (1,2,3,4)
+%!error cauchy_pdf (ones(3),ones(2),ones(2))
+%!error cauchy_pdf (ones(2),ones(3),ones(2))
+%!error cauchy_pdf (ones(2),ones(2),ones(3))
+%!error cauchy_pdf (i, 2, 2)
+%!error cauchy_pdf (2, i, 2)
+%!error cauchy_pdf (2, 2, i)
+
--- a/scripts/statistics/distributions/cauchy_rnd.m
+++ b/scripts/statistics/distributions/cauchy_rnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,78 +18,115 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} cauchy_rnd (@var{location}, @var{scale}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} cauchy_rnd (@var{location}, @var{scale}, @var{sz})
-## Return an @var{r} by @var{c} or a @code{size (@var{sz})} matrix of
-## random samples from the Cauchy distribution with parameters @var{location}
-## and @var{scale} which must both be scalar or of size @var{r} by @var{c}.
+## @deftypefn  {Function File} {} cauchy_rnd (@var{location}, @var{scale})
+## @deftypefnx {Function File} {} cauchy_rnd (@var{location}, @var{scale}, @var{r})
+## @deftypefnx {Function File} {} cauchy_rnd (@var{location}, @var{scale}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} cauchy_rnd (@var{location}, @var{scale}, [@var{sz}])
+## Return a matrix of random samples from the Cauchy distribution with
+## parameters @var{location} and @var{scale}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{location} and @var{scale}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{location} and @var{scale}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the Cauchy distribution

-function rnd = cauchy_rnd (location, scale, r, c)
+function rnd = cauchy_rnd (location, scale, varargin)

-  if (nargin > 1)
-    if (!isscalar (location) || !isscalar (scale))
-      [retval, location, scale] = common_size (location, scale);
-      if (retval > 0)
-        error ("cauchy_rnd: LOCATION and SCALE must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (location) || !isscalar (scale))
+    [retval, location, scale] = common_size (location, scale);
+    if (retval > 0)
+      error ("cauchy_rnd: LOCATION and SCALE must be of common size or scalars");
     endif
   endif

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("cauchy_rnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("cauchy_rnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+  if (iscomplex (location) || iscomplex (scale))
+    error ("cauchy_rnd: LOCATION and SCALE must not be complex");
+  endif

-    if (any (size (location) != 1)
-        && (length (size (location)) != length (sz)
-            || any (size (location) != sz)))
-      error ("cauchy_rnd: LOCATION and SCALE must be scalar or of size [R, C]");
-    endif
+  if (nargin == 2)
+    sz = size (location);
   elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      error ("cauchy_rnd: R must be a positive integer or vector");
+      error ("cauchy_rnd: dimension vector must be row vector of non-negative integers");
     endif
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("cauchy_rnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif

-    if (any (size (location) != 1)
-        && (length (size (location)) != length (sz)
-        || any (size (location) != sz)))
-      error ("cauchy_rnd: LOCATION and SCALE must be scalar or of size SZ");
-    endif
-  elseif (nargin == 2)
-    sz = size(location);
+  if (!isscalar (location) && !isequal (size (location), sz))
+    error ("cauchy_rnd: LOCATION and SCALE must be scalar or of size SZ");
+  endif
+
+  if (isa (location, "single") || isa (scale, "single"))
+    cls = "single";
   else
-    print_usage ();
+    cls = "double";
   endif

   if (isscalar (location) && isscalar (scale))
-    if (find (!(location > -Inf) | !(location < Inf)
-                | !(scale > 0) | !(scale < Inf)))
-      rnd = NaN (sz);
+    if (!isinf (location) && (scale > 0) && (scale < Inf))
+      rnd = location - cot (pi * rand (sz)) * scale;
     else
-      rnd = location - cot (pi * rand (sz)) .* scale;
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = NaN (sz);
-    k = find ((location > -Inf) & (location < Inf)
-              & (scale > 0) & (scale < Inf));
-    if (any (k))
-      rnd(k) = location(k)(:) - cot (pi * rand (size (k))) .* scale(k)(:);
-    endif
+    rnd = NaN (sz, cls);
+
+    k = !isinf (location) & (scale > 0) & (scale < Inf);
+    rnd(k) = location(k)(:) - cot (pi * rand (sum (k(:)), 1)) .* scale(k)(:);
   endif

 endfunction
+
+
+%!assert(size (cauchy_rnd (1,2)), [1, 1]);
+%!assert(size (cauchy_rnd (ones(2,1), 2)), [2, 1]);
+%!assert(size (cauchy_rnd (ones(2,2), 2)), [2, 2]);
+%!assert(size (cauchy_rnd (1, 2*ones(2,1))), [2, 1]);
+%!assert(size (cauchy_rnd (1, 2*ones(2,2))), [2, 2]);
+%!assert(size (cauchy_rnd (1, 2, 3)), [3, 3]);
+%!assert(size (cauchy_rnd (1, 2, [4 1])), [4, 1]);
+%!assert(size (cauchy_rnd (1, 2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (cauchy_rnd (1, 2)), "double");
+%!assert(class (cauchy_rnd (single(1), 2)), "single");
+%!assert(class (cauchy_rnd (single([1 1]), 2)), "single");
+%!assert(class (cauchy_rnd (1, single(2))), "single");
+%!assert(class (cauchy_rnd (1, single([2 2]))), "single");
+
+%% Test input validation
+%!error cauchy_rnd ()
+%!error cauchy_rnd (1)
+%!error cauchy_rnd (ones(3),ones(2))
+%!error cauchy_rnd (ones(2),ones(3))
+%!error cauchy_rnd (i, 2)
+%!error cauchy_rnd (2, i)
+%!error cauchy_rnd (1,2, -1)
+%!error cauchy_rnd (1,2, ones(2))
+%!error cauchy_rnd (1,2, [2 -1 2])
+%!error cauchy_rnd (1,2, 1, ones(2))
+%!error cauchy_rnd (1,2, 1, -1)
+%!error cauchy_rnd (ones(2,2), 2, 3)
+%!error cauchy_rnd (ones(2,2), 2, [3, 2])
+%!error cauchy_rnd (ones(2,2), 2, 2, 3)
+
--- a/scripts/statistics/distributions/chi2cdf.m
+++ b/scripts/statistics/distributions/chi2cdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -19,7 +20,7 @@
 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} chi2cdf (@var{x}, @var{n})
 ## For each element of @var{x}, compute the cumulative distribution
-## function (CDF) at @var{x} of the chisquare distribution with @var{n}
+## function (CDF) at @var{x} of the chi-square distribution with @var{n}
 ## degrees of freedom.
 ## @end deftypefn

@@ -35,10 +36,38 @@
   if (!isscalar (n))
     [retval, x, n] = common_size (x, n);
     if (retval > 0)
-      error ("chi2cdf: X and N must be of common size or scalar");
+      error ("chi2cdf: X and N must be of common size or scalars");
     endif
   endif

-  cdf = gamcdf (x, n / 2, 2);
+  if (iscomplex (x) || iscomplex (n))
+    error ("chi2cdf: X and N must not be complex");
+  endif
+
+  cdf = gamcdf (x, n/2, 2);

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2];
+%! y = [0, 1 - exp(-x(2:end)/2)];
+%!assert(chi2cdf (x, 2*ones(1,5)), y, eps);
+%!assert(chi2cdf (x, 2), y, eps);
+%!assert(chi2cdf (x, 2*[1 0 NaN 1 1]), [y(1) NaN NaN y(4:5)], eps);
+%!assert(chi2cdf ([x(1:2) NaN x(4:5)], 2), [y(1:2) NaN y(4:5)], eps);
+
+%% Test class of input preserved
+%!assert(chi2cdf ([x, NaN], 2), [y, NaN], eps);
+%!assert(chi2cdf (single([x, NaN]), 2), single([y, NaN]), eps("single"));
+%!assert(chi2cdf ([x, NaN], single(2)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error chi2cdf ()
+%!error chi2cdf (1)
+%!error chi2cdf (1,2,3)
+%!error chi2cdf (ones(3),ones(2))
+%!error chi2cdf (ones(2),ones(3))
+%!error chi2cdf (i, 2)
+%!error chi2cdf (2, i)
+
--- a/scripts/statistics/distributions/chi2inv.m
+++ b/scripts/statistics/distributions/chi2inv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -19,7 +20,7 @@
 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} chi2inv (@var{x}, @var{n})
 ## For each element of @var{x}, compute the quantile (the inverse of the
-## CDF) at @var{x} of the chisquare distribution with @var{n} degrees of
+## CDF) at @var{x} of the chi-square distribution with @var{n} degrees of
 ## freedom.
 ## @end deftypefn

@@ -35,10 +36,37 @@
   if (!isscalar (n))
     [retval, x, n] = common_size (x, n);
     if (retval > 0)
-      error ("chi2inv: X and N must be of common size or scalar");
+      error ("chi2inv: X and N must be of common size or scalars");
     endif
   endif

-  inv = gaminv (x, n / 2, 2);
+  if (iscomplex (x) || iscomplex (n))
+    error ("chi2inv: X and N must not be complex");
+  endif
+
+  inv = gaminv (x, n/2, 2);

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.3934693402873666 1 2];
+%!assert(chi2inv (x, 2*ones(1,5)), [NaN 0 1 Inf NaN], 5*eps);
+%!assert(chi2inv (x, 2), [NaN 0 1 Inf NaN], 5*eps);
+%!assert(chi2inv (x, 2*[0 1 NaN 1 1]), [NaN 0 NaN Inf NaN], 5*eps);
+%!assert(chi2inv ([x(1:2) NaN x(4:5)], 2), [NaN 0 NaN Inf NaN], 5*eps);
+
+%% Test class of input preserved
+%!assert(chi2inv ([x, NaN], 2), [NaN 0 1 Inf NaN NaN], 5*eps);
+%!assert(chi2inv (single([x, NaN]), 2), single([NaN 0 1 Inf NaN NaN]), 5*eps("single"));
+%!assert(chi2inv ([x, NaN], single(2)), single([NaN 0 1 Inf NaN NaN]), 5*eps("single"));
+
+%% Test input validation
+%!error chi2inv ()
+%!error chi2inv (1)
+%!error chi2inv (1,2,3)
+%!error chi2inv (ones(3),ones(2))
+%!error chi2inv (ones(2),ones(3))
+%!error chi2inv (i, 2)
+%!error chi2inv (2, i)
+
--- a/scripts/statistics/distributions/chi2pdf.m
+++ b/scripts/statistics/distributions/chi2pdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -19,7 +20,7 @@
 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} chi2pdf (@var{x}, @var{n})
 ## For each element of @var{x}, compute the probability density function
-## (PDF) at @var{x} of the chisquare distribution with @var{n} degrees
+## (PDF) at @var{x} of the chi-square distribution with @var{n} degrees
 ## of freedom.
 ## @end deftypefn

@@ -35,10 +36,37 @@
   if (!isscalar (n))
     [retval, x, n] = common_size (x, n);
     if (retval > 0)
-      error ("chi2pdf: X and N must be of common size or scalar");
+      error ("chi2pdf: X and N must be of common size or scalars");
     endif
   endif

-  pdf = gampdf (x, n / 2, 2);
+  if (iscomplex (x) || iscomplex (n))
+    error ("chi2pdf: X and N must not be complex");
+  endif
+
+  pdf = gampdf (x, n/2, 2);

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 Inf];
+%! y = [0, 1/2 * exp(-x(2:5)/2)];
+%!assert(chi2pdf (x, 2*ones(1,5)), y);
+%!assert(chi2pdf (x, 2), y);
+%!assert(chi2pdf (x, 2*[1 0 NaN 1 1]), [y(1) NaN NaN y(4:5)]);
+%!assert(chi2pdf ([x, NaN], 2), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(chi2pdf (single([x, NaN]), 2), single([y, NaN]));
+%!assert(chi2pdf ([x, NaN], single(2)), single([y, NaN]));
+
+%% Test input validation
+%!error chi2pdf ()
+%!error chi2pdf (1)
+%!error chi2pdf (1,2,3)
+%!error chi2pdf (ones(3),ones(2))
+%!error chi2pdf (ones(2),ones(3))
+%!error chi2pdf (i, 2)
+%!error chi2pdf (2, i)
+
--- a/scripts/statistics/distributions/chi2rnd.m
+++ b/scripts/statistics/distributions/chi2rnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,75 +18,103 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} chi2rnd (@var{n}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} chi2rnd (@var{n}, @var{sz})
-## Return an @var{r} by @var{c}  or a @code{size (@var{sz})} matrix of
-## random samples from the chisquare distribution with @var{n} degrees
-## of freedom.  @var{n} must be a scalar or of size @var{r} by @var{c}.
+## @deftypefn  {Function File} {} chi2rnd (@var{n})
+## @deftypefnx {Function File} {} chi2rnd (@var{n}, @var{r})
+## @deftypefnx {Function File} {} chi2rnd (@var{n}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} chi2rnd (@var{n}, [@var{sz}])
+## Return a matrix of random samples from the chi-square distribution with
+## @var{n} degrees of freedom.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the size of @var{n}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the size of
+## @var{n}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the chi-square distribution

-function rnd = chi2rnd (n, r, c)
-
-  if (nargin == 3)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("chi2rnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("chi2rnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+function rnd = chi2rnd (n, varargin)

-    if (any (size (n) != 1)
-        && (length (size (n)) != length (sz) || any (size (n) != sz)))
-      error ("chi2rnd: N must be scalar or of size [R, C]");
-    endif
-  elseif (nargin == 2)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("chi2rnd: R must be a positive integer or vector");
-    endif
-
-    if (any (size (n) != 1)
-        && (length (size (n)) != length (sz) || any (size (n) != sz)))
-      error ("chi2rnd: N must be scalar or of size SZ");
-    endif
-  elseif (nargin == 1)
-    sz = size(n);
-  else
+  if (nargin < 1)
     print_usage ();
   endif

-  if (isscalar (n))
-     if (find (!(n > 0) | !(n < Inf)))
-       rnd = NaN (sz);
-     else
-       rnd = 2 * randg(n/2, sz);
-     endif
-  else
-    [retval, n, dummy] = common_size (n, ones (sz));
-    if (retval > 0)
-      error ("chi2rnd: a and b must be of common size or scalar");
+  if (nargin == 1)
+    sz = size (n);
+  elseif (nargin == 2)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("chi2rnd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 2)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("chi2rnd: dimensions must be non-negative integers");
     endif
+    sz = [varargin{:}];
+  endif

-    rnd = zeros (sz);
-    k = find (!(n > 0) | !(n < Inf));
-    if (any (k))
-      rnd(k) = NaN;
+  if (!isscalar (n) && !isequal (size (n), sz))
+    error ("chi2rnd: N must be scalar or of size SZ");
+  endif
+
+  if (iscomplex (n))
+    error ("chi2rnd: N must not be complex");
+  endif
+
+  if (isa (n, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif
+
+  if (isscalar (n))
+    if ((n > 0) && (n < Inf))
+      rnd = 2 * randg (n/2, sz);
+      if (strcmp (cls, "single"))
+        rnd = single (rnd);
+      endif
+    else
+      rnd = NaN (sz, cls);
     endif
+  else
+    rnd = NaN (sz, cls);

-    k = find ((n > 0) & (n < Inf));
-    if (any (k))
-      rnd(k) = 2 * randg(n(k)/2, size(k));
-    endif
+    k = (n > 0) | (n < Inf);
+    rnd(k) = 2 * randg (n(k)/2);
   endif

 endfunction
+
+
+%!assert(size (chi2rnd (2)), [1, 1]);
+%!assert(size (chi2rnd (ones(2,1))), [2, 1]);
+%!assert(size (chi2rnd (ones(2,2))), [2, 2]);
+%!assert(size (chi2rnd (1, 3)), [3, 3]);
+%!assert(size (chi2rnd (1, [4 1])), [4, 1]);
+%!assert(size (chi2rnd (1, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (chi2rnd (2)), "double");
+%!assert(class (chi2rnd (single(2))), "single");
+%!assert(class (chi2rnd (single([2 2]))), "single");
+
+%% Test input validation
+%!error chi2rnd ()
+%!error chi2rnd (ones(3),ones(2))
+%!error chi2rnd (ones(2),ones(3))
+%!error chi2rnd (i)
+%!error chi2rnd (1, -1)
+%!error chi2rnd (1, ones(2))
+%!error chi2rnd (1, [2 -1 2])
+%!error chi2rnd (ones(2,2), 3)
+%!error chi2rnd (ones(2,2), [3, 2])
+%!error chi2rnd (ones(2,2), 2, 3)
+
--- a/scripts/statistics/distributions/discrete_cdf.m
+++ b/scripts/statistics/distributions/discrete_cdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 2010-2011 David Bateman
 ##
 ## This file is part of Octave.
@@ -29,28 +30,52 @@
     print_usage ();
   endif

-  sz = size (x);
-
   if (! isvector (v))
     error ("discrete_cdf: V must be a vector");
+  elseif (any (isnan (v)))
+    error ("discrete_cdf: V must not have any NaN elements");
   elseif (! isvector (p) || (length (p) != length (v)))
     error ("discrete_cdf: P must be a vector with length (V) elements");
   elseif (! (all (p >= 0) && any (p)))
-    error ("discrete_cdf: P must be a nonzero, nonnegative vector");
+    error ("discrete_cdf: P must be a nonzero, non-negative vector");
+  endif
+
+  p = p(:) / sum (p);   # Reshape and normalize probability vector
+
+  if (isa (x, "single") || isa (v, "single") || isa (p, "single"));
+    cdf = NaN (size (x), "single");
+  else
+    cdf = NaN (size (x));
   endif

-  n = numel (x);
-  m = length (v);
-  x = reshape (x, n, 1);
-  v = reshape (v, 1, m);
-  p = reshape (p / sum (p), m, 1);
-
-  cdf = NaN (sz);
-  k = find (!isnan (x));
-  if (any (k))
-    n = length (k);
-    [vs, vi] = sort (v);
-    cdf(k) = [0 ; cumsum(p(vi))](lookup (vs, x(k)) + 1);
-  endif
+  k = !isnan (x);
+  [vs, vi] = sort (v);
+  cdf(k) = [0 ; cumsum(p(vi))](lookup (vs, x(k)) + 1);

 endfunction
+
+
+%!shared x,v,p,y
+%! x = [-1 0.1 1.1 1.9 3];
+%! v = 0.1:0.2:1.9;
+%! p = 1/length(v) * ones(1, length(v));
+%! y = [0 0.1 0.6 1 1];
+%!assert(discrete_cdf ([x, NaN], v, p), [y, NaN], eps);
+
+%% Test class of input preserved
+%!assert(discrete_cdf (single([x, NaN]), v, p), single([y, NaN]), 2*eps("single"));
+%!assert(discrete_cdf ([x, NaN], single(v), p), single([y, NaN]), 2*eps("single"));
+%!assert(discrete_cdf ([x, NaN], v, single(p)), single([y, NaN]), 2*eps("single"));
+
+%% Test input validation
+%!error discrete_cdf ()
+%!error discrete_cdf (1)
+%!error discrete_cdf (1,2)
+%!error discrete_cdf (1,2,3,4)
+%!error discrete_cdf (1, ones(2), ones(2,1))
+%!error discrete_cdf (1, [1 ; NaN], ones(2,1))
+%!error discrete_cdf (1, ones(2,1), ones(1,1))
+%!error discrete_cdf (1, ones(2,1), [1 -1])
+%!error discrete_cdf (1, ones(2,1), [1 NaN])
+%!error discrete_cdf (1, ones(2,1), [0  0])
+
--- a/scripts/statistics/distributions/discrete_inv.m
+++ b/scripts/statistics/distributions/discrete_inv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1996-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,7 +19,7 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} discrete_inv (@var{x}, @var{v}, @var{p})
-## For each component of @var{x}, compute the quantile (the inverse of
+## For each element of @var{x}, compute the quantile (the inverse of
 ## the CDF) at @var{x} of the univariate distribution which assumes the
 ## values in @var{v} with probabilities @var{p}.
 ## @end deftypefn
@@ -32,35 +33,63 @@
     print_usage ();
   endif

-  sz = size (x);
-
   if (! isvector (v))
     error ("discrete_inv: V must be a vector");
   elseif (! isvector (p) || (length (p) != length (v)))
     error ("discrete_inv: P must be a vector with length (V) elements");
+  elseif (any (isnan (p)))
+    error ("discrete_rnd: P must not have any NaN elements");
   elseif (! (all (p >= 0) && any (p)))
-    error ("discrete_inv: P must be a nonzero, nonnegative vector");
+    error ("discrete_inv: P must be a nonzero, non-negative vector");
+  endif
+
+  if (isa (x, "single") || isa (v, "single") || isa (p, "single"));
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  n = numel (x);
-  x = reshape (x, 1, n);
-  m = length (v);
-  [v, idx] = sort (v);
-  p = reshape (cumsum (p (idx) / sum (p)), m, 1);
-
-  inv = NaN (sz);
-  if (any (k = find (x == 0)))
-    inv(k) = -Inf;
-  endif
-  if (any (k = find (x == 1)))
-    inv(k) = v(m) * ones (size (k));
+  ## FIXME: This isn't elegant.  But cumsum and lookup together produce
+  ## different results when called with a single or a double.
+  if (isa (p, "single"));
+    p = double (p);
   endif

-  if (any (k = find ((x > 0) & (x < 1))))
-    n = length (k);
-    inv (k) = v(length (p) - lookup (sort (p,"descend"), x(k)) + 1);
-  endif
+  [v, idx] = sort (v);
+  p = cumsum (p(idx)(:)) / sum (p);  # Reshape and normalize probability vector
+
+  k = (x == 0);
+  inv(k) = v(1);
+
+  k = (x == 1);
+  inv(k) = v(end);
+
+  k = (x > 0) & (x < 1);
+  inv(k) = v(length (p) - lookup (sort (p, "descend"), x(k)) + 1);

 endfunction


+%!shared x,v,p,y
+%! x = [-1 0 0.1 0.5 1 2];
+%! v = 0.1:0.2:1.9;
+%! p = 1/length(v) * ones(1, length(v));
+%! y = [NaN v(1) v(1) v(end/2) v(end) NaN];
+%!assert(discrete_inv ([x, NaN], v, p), [y, NaN], eps);
+
+%% Test class of input preserved
+%!assert(discrete_inv (single([x, NaN]), v, p), single([y, NaN]), eps("single"));
+%!assert(discrete_inv ([x, NaN], single(v), p), single([y, NaN]), eps("single"));
+%!assert(discrete_inv ([x, NaN], v, single(p)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error discrete_inv ()
+%!error discrete_inv (1)
+%!error discrete_inv (1,2)
+%!error discrete_inv (1,2,3,4)
+%!error discrete_inv (1, ones(2), ones(2,1))
+%!error discrete_inv (1, ones(2,1), ones(1,1))
+%!error discrete_inv (1, ones(2,1), [1 NaN])
+%!error discrete_inv (1, ones(2,1), [1 -1])
+%!error discrete_inv (1, ones(2,1), [0  0])
+
--- a/scripts/statistics/distributions/discrete_pdf.m
+++ b/scripts/statistics/distributions/discrete_pdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1996-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -24,7 +25,7 @@
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
-## Description: pDF of a discrete distribution
+## Description: PDF of a discrete distribution

 function pdf = discrete_pdf (x, v, p)

@@ -32,28 +33,53 @@
     print_usage ();
   endif

-  sz = size (x);
-
   if (! isvector (v))
     error ("discrete_pdf: V must be a vector");
+  elseif (any (isnan (v)))
+    error ("discrete_pdf: V must not have any NaN elements");
   elseif (! isvector (p) || (length (p) != length (v)))
     error ("discrete_pdf: P must be a vector with length (V) elements");
   elseif (! (all (p >= 0) && any (p)))
-    error ("discrete_pdf: P must be a nonzero, nonnegative vector");
+    error ("discrete_pdf: P must be a nonzero, non-negative vector");
+  endif
+
+  ## Reshape and normalize probability vector.  Values not in table get 0 prob.
+  p = [0 ; p(:)/sum(p)];
+
+  if (isa (x, "single") || isa (v, "single") || isa (p, "single"))
+    pdf = NaN (size (x), "single");
+  else
+    pdf = NaN (size (x));
   endif

-  n = numel (x);
-  m = length (v);
-  x = reshape (x, n, 1);
-  v = reshape (v, 1, m);
-  p = reshape (p / sum (p), m, 1);
-
-  pdf = NaN (sz);
-  k = find (!isnan (x));
-  if (any (k))
-    n = length (k);
-    [vs, vi] = sort (v);
-    pdf (k) = p (vi(lookup (vs, x(k), 'm')));
-  endif
+  k = !isnan (x);
+  [vs, vi] = sort (v(:));
+  pdf(k) = p([0 ; vi](lookup (vs, x(k), 'm') + 1) + 1);

 endfunction
+
+
+%!shared x,v,p,y
+%! x = [-1 0.1 1.1 1.9 3];
+%! v = 0.1:0.2:1.9;
+%! p = 1/length(v) * ones(1, length(v));
+%! y = [0 0.1 0.1 0.1 0];
+%!assert(discrete_pdf ([x, NaN], v, p), [y, NaN], 5*eps);
+
+%% Test class of input preserved
+%!assert(discrete_pdf (single([x, NaN]), v, p), single([y, NaN]), 5*eps("single"));
+%!assert(discrete_pdf ([x, NaN], single(v), p), single([y, NaN]), 5*eps("single"));
+%!assert(discrete_pdf ([x, NaN], v, single(p)), single([y, NaN]), 5*eps("single"));
+
+%% Test input validation
+%!error discrete_pdf ()
+%!error discrete_pdf (1)
+%!error discrete_pdf (1,2)
+%!error discrete_pdf (1,2,3,4)
+%!error discrete_pdf (1, ones(2), ones(2,1))
+%!error discrete_pdf (1, [1 ; NaN], ones(2,1))
+%!error discrete_pdf (1, ones(2,1), ones(1,1))
+%!error discrete_pdf (1, ones(2,1), [1 -1])
+%!error discrete_pdf (1, ones(2,1), [1 NaN])
+%!error discrete_pdf (1, ones(2,1), [0  0])
+
--- a/scripts/statistics/distributions/discrete_rnd.m
+++ b/scripts/statistics/distributions/discrete_rnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1996-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,51 +18,29 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} discrete_rnd (@var{n}, @var{v}, @var{p})
-## @deftypefnx {Function File} {} discrete_rnd (@var{v}, @var{p}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} discrete_rnd (@var{v}, @var{p}, @var{sz})
-## Generate a row vector containing a random sample of size @var{n} from
-## the univariate distribution which assumes the values in @var{v} with
-## probabilities @var{p}.  @var{n} must be a scalar.
+## @deftypefn  {Function File} {} discrete_rnd (@var{v}, @var{p})
+## @deftypefnx {Function File} {} discrete_rnd (@var{v}, @var{p}, @var{r})
+## @deftypefnx {Function File} {} discrete_rnd (@var{v}, @var{p}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} discrete_rnd (@var{v}, @var{p}, [@var{sz}])
+## Return a matrix of random samples from the univariate distribution which
+## assumes the values in @var{v} with probabilities @var{p}.
 ##
-## If @var{r} and @var{c} are given create a matrix with @var{r} rows and
-## @var{c} columns.  Or if @var{sz} is a vector, create a matrix of size
-## @var{sz}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{v} and @var{p}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from a discrete distribution

-function rnd = discrete_rnd (v, p, r, c)
+function rnd = discrete_rnd (v, p, varargin)

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("discrete_rnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("discrete_rnd: C must be a positive integer");
-    endif
-    sz = [r, c];
-  elseif (nargin == 3)
-    ## A potential problem happens here if all args are scalar, as
-    ## we can't distiguish between the command syntax. Thankfully this
-    ## case doesn't make much sense. So we assume the first syntax
-    ## if the first arg is scalar
-
-    if (isscalar (v))
-      sz = [1, floor(v)];
-      v = p;
-      p = r;
-    else
-      if (isscalar (r) && (r > 0))
-        sz = [r, r];
-      elseif (isvector(r) && all (r > 0))
-        sz = r(:)';
-      else
-        error ("discrete_rnd: R must be a positive integer or vector");
-      endif
-    endif
-  else
+  if (nargin < 2)
     print_usage ();
   endif

@@ -69,9 +48,57 @@
     error ("discrete_rnd: V must be a vector");
   elseif (! isvector (p) || (length (p) != length (v)))
     error ("discrete_rnd: P must be a vector with length (V) elements");
+  elseif (any (isnan (p)))
+    error ("discrete_rnd: P must not have any NaN elements");
   elseif (! (all (p >= 0) && any (p)))
-    error ("discrete_rnd: P must be a nonzero, nonnegative vector");
+    error ("discrete_rnd: P must be a nonzero, non-negative vector");
+  endif
+
+  if (nargin == 2)
+    sz = size (v);
+  elseif (nargin == 3)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("discrete_rnd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("discrete_rnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
   endif

-  rnd = v (lookup (cumsum (p (1 : end-1)) / sum(p), rand (sz)) + 1);
+  rnd = v(lookup (cumsum (p(1:end-1)) / sum (p), rand (sz)) + 1);
+  rnd = reshape (rnd, sz);
+
 endfunction
+
+
+%!assert(size (discrete_rnd (1:2, 1:2, 3)), [3, 3]);
+%!assert(size (discrete_rnd (1:2, 1:2, [4 1])), [4, 1]);
+%!assert(size (discrete_rnd (1:2, 1:2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (discrete_rnd (1:2, 1:2)), "double");
+%!assert(class (discrete_rnd (single(1:2), 1:2)), "single");
+## FIXME: Maybe this should work, maybe it shouldn't.
+#%!assert(class (discrete_rnd (1:2, single(1:2))), "single");
+
+%% Test input validation
+%!error discrete_rnd ()
+%!error discrete_rnd (1)
+%!error discrete_rnd (1:2,1:2, -1)
+%!error discrete_rnd (1:2,1:2, ones(2))
+%!error discrete_rnd (1:2,1:2, [2 -1 2])
+%!error discrete_rnd (1:2,1:2, 1, ones(2))
+%!error discrete_rnd (1:2,1:2, 1, -1)
+%% test v,p verification
+%!error discrete_rnd (1, ones(2), ones(2,1))
+%!error discrete_rnd (1, ones(2,1), ones(1,1))
+%!error discrete_rnd (1, ones(2,1), [1 -1])
+%!error discrete_rnd (1, ones(2,1), [1 NaN])
+%!error discrete_rnd (1, ones(2,1), [0  0])
+
--- a/scripts/statistics/distributions/empirical_cdf.m
+++ b/scripts/statistics/distributions/empirical_cdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1996-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -36,6 +37,26 @@
     error ("empirical_cdf: DATA must be a vector");
   endif

-  cdf = discrete_cdf (x, data, ones (size (data)) / length (data));
+  cdf = discrete_cdf (x, data, ones (size (data)));

 endfunction
+
+
+%!shared x,v,y
+%! x = [-1 0.1 1.1 1.9 3];
+%! v = 0.1:0.2:1.9;
+%! y = [0 0.1 0.6 1 1];
+%!assert(empirical_cdf (x, v), y, eps);
+%!assert(empirical_cdf ([x(1) NaN x(3:5)], v), [0 NaN 0.6 1 1], eps);
+
+%% Test class of input preserved
+%!assert(empirical_cdf ([x, NaN], v), [y, NaN], eps);
+%!assert(empirical_cdf (single([x, NaN]), v), single([y, NaN]), eps);
+%!assert(empirical_cdf ([x, NaN], single(v)), single([y, NaN]), eps);
+
+%% Test input validation
+%!error empirical_cdf ()
+%!error empirical_cdf (1)
+%!error empirical_cdf (1,2,3)
+%!error empirical_cdf (1, ones(2))
+
--- a/scripts/statistics/distributions/empirical_inv.m
+++ b/scripts/statistics/distributions/empirical_inv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1996-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -36,6 +37,25 @@
     error ("empirical_inv: DATA must be a vector");
   endif

-  inv = discrete_inv (x, data, ones (size (data)) / length (data));
+  inv = discrete_inv (x, data, ones (size (data)));

 endfunction
+
+
+%!shared x,v,y
+%! x = [-1 0 0.1 0.5 1 2];
+%! v = 0.1:0.2:1.9;
+%! y = [NaN v(1) v(1) v(end/2) v(end) NaN];
+%!assert(empirical_inv (x, v), y, eps);
+
+%% Test class of input preserved
+%!assert(empirical_inv ([x, NaN], v), [y, NaN], eps);
+%!assert(empirical_inv (single([x, NaN]), v), single([y, NaN]), eps);
+%!assert(empirical_inv ([x, NaN], single(v)), single([y, NaN]), eps);
+
+%% Test input validation
+%!error empirical_inv ()
+%!error empirical_inv (1)
+%!error empirical_inv (1,2,3)
+%!error empirical_inv (1, ones(2))
+
--- a/scripts/statistics/distributions/empirical_pdf.m
+++ b/scripts/statistics/distributions/empirical_pdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1996-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -36,6 +37,24 @@
     error ("empirical_pdf: DATA must be a vector");
   endif

-  pdf = discrete_pdf (x, data, ones (size (data)) / length (data));
+  pdf = discrete_pdf (x, data, ones (size (data)));

 endfunction
+
+
+%!shared x,v,y
+%! x = [-1 0.1 1.1 1.9 3];
+%! v = 0.1:0.2:1.9;
+%! y = [0 0.1 0.1 0.1 0];
+%!assert(empirical_pdf (x, v), y);
+
+%% Test class of input preserved
+%!assert(empirical_pdf (single(x), v), single (y));
+%!assert(empirical_pdf (x, single(v)), single (y));
+
+%% Test input validation
+%!error empirical_pdf ()
+%!error empirical_pdf (1)
+%!error empirical_pdf (1,2,3)
+%!error empirical_inv (1, ones(2))
+
--- a/scripts/statistics/distributions/empirical_rnd.m
+++ b/scripts/statistics/distributions/empirical_rnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1996-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,29 +18,29 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} empirical_rnd (@var{n}, @var{data})
-## @deftypefnx {Function File} {} empirical_rnd (@var{data}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} empirical_rnd (@var{data}, @var{sz})
-## Generate a bootstrap sample of size @var{n} from the empirical
-## distribution obtained from the univariate sample @var{data}.
+## @deftypefn  {Function File} {} empirical_rnd (@var{data})
+## @deftypefnx {Function File} {} empirical_rnd (@var{data}, @var{r})
+## @deftypefnx {Function File} {} empirical_rnd (@var{data}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} empirical_rnd (@var{data}, [@var{sz}])
+## Return a matrix of random samples from the empirical distribution obtained
+## from the univariate sample @var{data}.
 ##
-## If @var{r} and @var{c} are given create a matrix with @var{r} rows and
-## @var{c} columns.  Or if @var{sz} is a vector, create a matrix of size
-## @var{sz}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is a random ordering
+## of the sample @var{data}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Bootstrap samples from the empirical distribution

-function rnd = empirical_rnd (data, r, c)
+function rnd = empirical_rnd (data, varargin)

-  if (nargin == 2)
-    if (isscalar(data))
-      c = data;
-      data = r;
-      r = 1;
-    endif
-  elseif (nargin != 3)
+  if (nargin < 1)
     print_usage ();
   endif

@@ -47,6 +48,22 @@
     error ("empirical_rnd: DATA must be a vector");
   endif

-  rnd = discrete_rnd (data, ones (size (data)) / length (data), r, c);
+  rnd = discrete_rnd (data, ones (size (data)), varargin{:});

 endfunction
+
+
+%!assert(size (empirical_rnd (ones (3, 1))), [3, 1]);
+%!assert(size (empirical_rnd (1:2, [4 1])), [4, 1]);
+%!assert(size (empirical_rnd (1:2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (empirical_rnd (1:2, 1)), "double");
+%!assert(class (empirical_rnd (single(1:2), 1)), "single");
+
+%% Test input validation
+%!error empirical_rnd ()
+%!error empirical_rnd (ones(2), 1)
+%% test data verification
+%!error empirical_rnd (ones(2), 1, 1)
+
--- a/scripts/statistics/distributions/expcdf.m
+++ b/scripts/statistics/distributions/expcdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -22,7 +23,7 @@
 ## function (CDF) at @var{x} of the exponential distribution with
 ## mean @var{lambda}.
 ##
-## The arguments can be of common size or scalar.
+## The arguments can be of common size or scalars.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -34,40 +35,57 @@
     print_usage ();
   endif

-  if (!isscalar (x) && !isscalar(lambda))
+  if (!isscalar (lambda))
     [retval, x, lambda] = common_size (x, lambda);
     if (retval > 0)
-      error ("expcdf: X and LAMBDA must be of common size or scalar");
+      error ("expcdf: X and LAMBDA must be of common size or scalars");
     endif
   endif

-  if (isscalar (x))
-    sz = size (lambda);
-  else
-    sz = size (x);
+  if (iscomplex (x) || iscomplex (lambda))
+    error ("expcdf: X and LAMBDA must not be complex");
   endif

-  cdf = zeros (sz);
-
-  k = find (isnan (x) | !(lambda > 0));
-  if (any (k))
-    cdf(k) = NaN;
+  if (isa (x, "single") || isa (lambda, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x == Inf) & (lambda > 0));
-  if (any (k))
-    cdf(k) = 1;
-  endif
+  k = isnan (x) | !(lambda > 0);
+  cdf(k) = NaN;
+
+  k = (x == Inf) & (lambda > 0);
+  cdf(k) = 1;

-  k = find ((x > 0) & (x < Inf) & (lambda > 0));
-  if (any (k))
-    if isscalar (lambda)
-      cdf (k) = 1 - exp (- x(k) ./ lambda);
-    elseif isscalar (x)
-      cdf (k) = 1 - exp (- x ./ lambda(k));
-    else
-      cdf (k) = 1 - exp (- x(k) ./ lambda(k));
-    endif
+  k = (x > 0) & (x < Inf) & (lambda > 0);
+  if isscalar (lambda)
+    cdf(k) = 1 - exp (- x(k) / lambda);
+  else
+    cdf(k) = 1 - exp (- x(k) ./ lambda(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 Inf];
+%! y = [0, 1 - exp(-x(2:end)/2)];
+%!assert(expcdf (x, 2*ones(1,5)), y);
+%!assert(expcdf (x, 2), y);
+%!assert(expcdf (x, 2*[1 0 NaN 1 1]), [y(1) NaN NaN y(4:5)]);
+
+%% Test class of input preserved
+%!assert(expcdf ([x, NaN], 2), [y, NaN]);
+%!assert(expcdf (single([x, NaN]), 2), single([y, NaN]));
+%!assert(expcdf ([x, NaN], single(2)), single([y, NaN]));
+
+%% Test input validation
+%!error expcdf ()
+%!error expcdf (1)
+%!error expcdf (1,2,3)
+%!error expcdf (ones(3),ones(2))
+%!error expcdf (ones(2),ones(3))
+%!error expcdf (i, 2)
+%!error expcdf (2, i)
+
--- a/scripts/statistics/distributions/expinv.m
+++ b/scripts/statistics/distributions/expinv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -19,8 +20,7 @@
 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} expinv (@var{x}, @var{lambda})
 ## For each element of @var{x}, compute the quantile (the inverse of the
-## CDF) at @var{x} of the exponential distribution with mean
-## @var{lambda}.
+## CDF) at @var{x} of the exponential distribution with mean @var{lambda}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -32,41 +32,64 @@
     print_usage ();
   endif

-  if (!isscalar (x) && !isscalar(lambda))
+  if (!isscalar (lambda))
     [retval, x, lambda] = common_size (x, lambda);
     if (retval > 0)
-      error ("expinv: X and LAMBDA must be of common size or scalar");
+      error ("expinv: X and LAMBDA must be of common size or scalars");
     endif
   endif

-  if (isscalar (x))
-    sz = size (lambda);
-  else
-    sz = size (x);
+  if (iscomplex (x) || iscomplex (lambda))
+    error ("expinv: X and LAMBDA must not be complex");
   endif

-  inv = zeros (sz);
+  if (!isscalar (x))
+    sz = size (x);
+  else
+    sz = size (lambda);
+  endif

-  k = find (!(lambda > 0) | (x < 0) | (x > 1) | isnan (x));
-  if (any (k))
-    inv(k) = NaN;
+  if (iscomplex (x) || iscomplex (lambda))
+    error ("expinv: X and LAMBDA must not be complex");
   endif

-  k = find ((x == 1) & (lambda > 0));
-  if (any (k))
-    inv(k) = Inf;
+  if (isa (x, "single") || isa (lambda, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  k = find ((x > 0) & (x < 1) & (lambda > 0));
-  if (any (k))
-    if isscalar (lambda)
-      inv(k) = - lambda .* log (1 - x(k));
-    elseif isscalar (x)
-      inv(k) = - lambda(k) .* log (1 - x);
-    else
-      inv(k) = - lambda(k) .* log (1 - x(k));
-    endif
+  k = (x == 1) & (lambda > 0);
+  inv(k) = Inf;
+
+  k = (x >= 0) & (x < 1) & (lambda > 0);
+  if isscalar (lambda)
+    inv(k) = - lambda * log (1 - x(k));
+  else
+    inv(k) = - lambda(k) .* log (1 - x(k));
   endif

 endfunction

+
+%!shared x
+%! x = [-1 0 0.3934693402873666 1 2];
+%!assert(expinv (x, 2*ones(1,5)), [NaN 0 1 Inf NaN], eps);
+%!assert(expinv (x, 2), [NaN 0 1 Inf NaN], eps);
+%!assert(expinv (x, 2*[1 0 NaN 1 1]), [NaN NaN NaN Inf NaN], eps);
+%!assert(expinv ([x(1:2) NaN x(4:5)], 2), [NaN 0 NaN Inf NaN], eps);
+
+%% Test class of input preserved
+%!assert(expinv ([x, NaN], 2), [NaN 0 1 Inf NaN NaN], eps);
+%!assert(expinv (single([x, NaN]), 2), single([NaN 0 1 Inf NaN NaN]), eps);
+%!assert(expinv ([x, NaN], single(2)), single([NaN 0 1 Inf NaN NaN]), eps);
+
+%% Test input validation
+%!error expinv ()
+%!error expinv (1)
+%!error expinv (1,2,3)
+%!error expinv (ones(3),ones(2))
+%!error expinv (ones(2),ones(3))
+%!error expinv (i, 2)
+%!error expinv (2, i)
+
--- a/scripts/statistics/distributions/exppdf.m
+++ b/scripts/statistics/distributions/exppdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -19,7 +20,7 @@
 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} exppdf (@var{x}, @var{lambda})
 ## For each element of @var{x}, compute the probability density function
-## (PDF) of the exponential distribution with mean @var{lambda}.
+## (PDF) at @var{x} of the exponential distribution with mean @var{lambda}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -31,34 +32,53 @@
     print_usage ();
   endif

-  if (!isscalar (x) && !isscalar(lambda))
+  if (!isscalar (lambda))
     [retval, x, lambda] = common_size (x, lambda);
     if (retval > 0)
-      error ("exppdf: X and LAMBDA must be of common size or scalar");
+      error ("exppdf: X and LAMBDA must be of common size or scalars");
     endif
   endif

-  if (isscalar (x))
-    sz = size (lambda);
-  else
-    sz = size (x);
-  endif
-  pdf = zeros (sz);
-
-  k = find (!(lambda > 0) | isnan (x));
-  if (any (k))
-    pdf(k) = NaN;
+  if (iscomplex (x) || iscomplex (lambda))
+    error ("exppdf: X and LAMBDA must not be complex");
   endif

-  k = find ((x >= 0) & (x < Inf) & (lambda > 0));
-  if (any (k))
-    if isscalar (lambda)
-      pdf(k) = exp (- x(k) ./ lambda) ./ lambda;
-    elseif isscalar (x)
-      pdf(k) = exp (- x ./ lambda(k)) ./ lambda(k);
-    else
-      pdf(k) = exp (- x(k) ./ lambda(k)) ./ lambda(k);
-    endif
+  if (isa (x, "single") || isa (lambda, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
+  endif
+
+  k = isnan (x) | !(lambda > 0);
+  pdf(k) = NaN;
+
+  k = (x >= 0) & (x < Inf) & (lambda > 0);
+  if isscalar (lambda)
+    pdf(k) = exp (- x(k) / lambda) / lambda;
+  else
+    pdf(k) = exp (- x(k) ./ lambda(k)) ./ lambda(k);
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 Inf];
+%! y = gampdf (x, 1, 2);
+%!assert(exppdf (x, 2*ones(1,5)), y);
+%!assert(exppdf (x, 2*[1 0 NaN 1 1]), [y(1) NaN NaN y(4:5)]);
+%!assert(exppdf ([x, NaN], 2), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(exppdf (single([x, NaN]), 2), single([y, NaN]));
+%!assert(exppdf ([x, NaN], single(2)), single([y, NaN]));
+
+%% Test input validation
+%!error exppdf ()
+%!error exppdf (1)
+%!error exppdf (1,2,3)
+%!error exppdf (ones(3),ones(2))
+%!error exppdf (ones(2),ones(3))
+%!error exppdf (i, 2)
+%!error exppdf (2, i)
+
--- a/scripts/statistics/distributions/exprnd.m
+++ b/scripts/statistics/distributions/exprnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,71 +18,100 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} exprnd (@var{lambda}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} exprnd (@var{lambda}, @var{sz})
-## Return an @var{r} by @var{c} matrix of random samples from the
-## exponential distribution with mean @var{lambda}, which must be a
-## scalar or of size @var{r} by @var{c}.  Or if @var{sz} is a vector,
-## create a matrix of size @var{sz}.
+## @deftypefn  {Function File} {} exprnd (@var{lambda})
+## @deftypefnx {Function File} {} exprnd (@var{lambda}, @var{r})
+## @deftypefnx {Function File} {} exprnd (@var{lambda}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} exprnd (@var{lambda}, [@var{sz}])
+## Return a matrix of random samples from the exponential distribution with
+## mean @var{lambda}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the size of @var{lambda}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the size of
+## @var{lambda}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the exponential distribution

-function rnd = exprnd (lambda, r, c)
-
-  if (nargin == 3)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("exprnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("exprnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+function rnd = exprnd (lambda, varargin)

-    if (any (size (lambda) != 1)
-        && (length (size (lambda)) != length (sz) || any (size (lambda) != sz)))
-      error ("exprnd: LAMBDA must be scalar or of size [R, C]");
-    endif
-  elseif (nargin == 2)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("exprnd: R must be a positive integer or vector");
-    endif
-
-    if (any (size (lambda) != 1)
-        && ((length (size (lambda)) != length (sz)) || any (size (lambda) != sz)))
-      error ("exprnd: LAMBDA must be scalar or of size SZ");
-    endif
-  elseif (nargin == 1)
-    sz = size (lambda);
-  else
+  if (nargin < 1)
     print_usage ();
   endif

+  if (nargin == 1)
+    sz = size (lambda);
+  elseif (nargin == 2)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("exprnd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 2)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("exprnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif
+
+  if (!isscalar (lambda) && !isequal (size (lambda), sz))
+    error ("exprnd: LAMBDA must be scalar or of size SZ");
+  endif
+
+  if (iscomplex (lambda))
+    error ("exprnd: LAMBDA must not be complex");
+  endif
+
+  if (isa (lambda, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif

   if (isscalar (lambda))
     if ((lambda > 0) && (lambda < Inf))
-      rnd = rande(sz) * lambda;
+      rnd = rande (sz) * lambda;
     else
-      rnd = NaN (sz);
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = zeros (sz);
-    k = find (!(lambda > 0) | !(lambda < Inf));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
-    k = find ((lambda > 0) & (lambda < Inf));
-    if (any (k))
-      rnd(k) = rande(size(k)) .* lambda(k);
-    endif
+    rnd = NaN (sz, cls);
+
+    k = (lambda > 0) & (lambda < Inf);
+    rnd(k) = rande (sum (k(:)), 1) .* lambda(k)(:);
   endif

 endfunction
+
+
+%!assert(size (exprnd (2)), [1, 1]);
+%!assert(size (exprnd (ones(2,1))), [2, 1]);
+%!assert(size (exprnd (ones(2,2))), [2, 2]);
+%!assert(size (exprnd (1, 3)), [3, 3]);
+%!assert(size (exprnd (1, [4 1])), [4, 1]);
+%!assert(size (exprnd (1, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (exprnd (1)), "double");
+%!assert(class (exprnd (single(1))), "single");
+%!assert(class (exprnd (single([1 1]))), "single");
+
+%% Test input validation
+%!error exprnd ()
+%!error exprnd (1, -1)
+%!error exprnd (1, ones(2))
+%!error exprnd (i)
+%!error exprnd (1, [2 -1 2])
+%!error exprnd (1, 2, -1)
+%!error exprnd (1, 2, ones(2))
+%!error exprnd (ones(2,2), 3)
+%!error exprnd (ones(2,2), [3, 2])
+%!error exprnd (ones(2,2), 2, 3)
+
--- a/scripts/statistics/distributions/fcdf.m
+++ b/scripts/statistics/distributions/fcdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,9 +19,9 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} fcdf (@var{x}, @var{m}, @var{n})
-## For each element of @var{x}, compute the CDF at @var{x} of the F
-## distribution with @var{m} and @var{n} degrees of freedom, i.e.,
-## PROB (F (@var{m}, @var{n}) @leq{} @var{x}).
+## For each element of @var{x}, compute the cumulative distribution function
+## (CDF) at @var{x} of the F distribution with @var{m} and @var{n} degrees of
+## freedom.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -35,31 +36,61 @@
   if (!isscalar (m) || !isscalar (n))
     [retval, x, m, n] = common_size (x, m, n);
     if (retval > 0)
-      error ("fcdf: X, M and N must be of common size or scalar");
+      error ("fcdf: X, M, and N must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  cdf = zeros (sz);
+  if (iscomplex (x) || iscomplex (m) || iscomplex (n))
+    error ("fcdf: X, M, and N must not be complex");
+  endif

-  k = find (!(m > 0) | !(n > 0) | isnan (x));
-  if (any (k))
-    cdf(k) = NaN;
+  if (isa (x, "single") || isa (m, "single") || isa (n, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x == Inf) & (m > 0) & (n > 0));
-  if (any (k))
-    cdf(k) = 1;
-  endif
+  k = isnan (x) | !(m > 0) | !(m < Inf) | !(n > 0) | !(n < Inf);
+  cdf(k) = NaN;
+
+  k = (x == Inf) & (m > 0) & (m < Inf) & (n > 0) & (n < Inf);
+  cdf(k) = 1;

-  k = find ((x > 0) & (x < Inf) & (m > 0) & (n > 0));
-  if (any (k))
-    if (isscalar (m) && isscalar (n))
-      cdf(k) = 1 - betainc (1 ./ (1 + m .* x(k) ./ n), n / 2, m / 2);
-    else
-      cdf(k) = 1 - betainc (1 ./ (1 + m(k) .* x(k) ./ n(k)), n(k) / 2,
-                            m(k) / 2);
-    endif
+  k = (x > 0) & (x < Inf) & (m > 0) & (m < Inf) & (n > 0) & (n < Inf);
+  if (isscalar (m) && isscalar (n))
+    cdf(k) = 1 - betainc (1 ./ (1 + m * x(k) / n), n/2, m/2);
+  else
+    cdf(k) = 1 - betainc (1 ./ (1 + m(k) .* x(k) ./ n(k)), n(k)/2, m(k)/2);
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2 Inf];
+%! y = [0 0 1/3 1/2 2/3 1];
+%!assert(fcdf (x, 2*ones(1,6), 2*ones(1,6)), y, eps);
+%!assert(fcdf (x, 2, 2*ones(1,6)), y, eps);
+%!assert(fcdf (x, 2*ones(1,6), 2), y, eps);
+%!assert(fcdf (x, [0 NaN Inf 2 2 2], 2), [NaN NaN NaN y(4:6)], eps);
+%!assert(fcdf (x, 2, [0 NaN Inf 2 2 2]), [NaN NaN NaN y(4:6)], eps);
+%!assert(fcdf ([x(1:2) NaN x(4:6)], 2, 2), [y(1:2) NaN y(4:6)], eps);
+
+%% Test class of input preserved
+%!assert(fcdf ([x, NaN], 2, 2), [y, NaN], eps);
+%!assert(fcdf (single([x, NaN]), 2, 2), single([y, NaN]), eps("single"));
+%!assert(fcdf ([x, NaN], single(2), 2), single([y, NaN]), eps("single"));
+%!assert(fcdf ([x, NaN], 2, single(2)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error fcdf ()
+%!error fcdf (1)
+%!error fcdf (1,2)
+%!error fcdf (1,2,3,4)
+%!error fcdf (ones(3),ones(2),ones(2))
+%!error fcdf (ones(2),ones(3),ones(2))
+%!error fcdf (ones(2),ones(2),ones(3))
+%!error fcdf (i, 2, 2)
+%!error fcdf (2, i, 2)
+%!error fcdf (2, 2, i)
+
--- a/scripts/statistics/distributions/finv.m
+++ b/scripts/statistics/distributions/finv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,9 +19,9 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} finv (@var{x}, @var{m}, @var{n})
-## For each component of @var{x}, compute the quantile (the inverse of
-## the CDF) at @var{x} of the F distribution with parameters @var{m} and
-## @var{n}.
+## For each element of @var{x}, compute the quantile (the inverse of
+## the CDF) at @var{x} of the F distribution with @var{m} and @var{n}
+## degrees of freedom.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -35,31 +36,58 @@
   if (!isscalar (m) || !isscalar (n))
     [retval, x, m, n] = common_size (x, m, n);
     if (retval > 0)
-      error ("finv: X, M and N must be of common size or scalar");
+      error ("finv: X, M, and N must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  inv = zeros (sz);
+  if (iscomplex (x) || iscomplex (m) || iscomplex (n))
+    error ("finv: X, M, and N must not be complex");
+  endif

-  k = find ((x < 0) | (x > 1) | isnan (x) | !(m > 0) | !(n > 0));
-  if (any (k))
-    inv(k) = NaN;
+  if (isa (x, "single") || isa (m, "single") || isa (n, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  k = find ((x == 1) & (m > 0) & (n > 0));
-  if (any (k))
-    inv(k) = Inf;
-  endif
+  k = (x == 1) & (m > 0) & (m < Inf) & (n > 0) & (n < Inf);
+  inv(k) = Inf;

-  k = find ((x > 0) & (x < 1) & (m > 0) & (n > 0));
-  if (any (k))
-    if (isscalar (m) && isscalar (n))
-      inv(k) = ((1 ./ betainv (1 - x(k), n / 2, m / 2) - 1) .* n ./ m);
-    else
-      inv(k) = ((1 ./ betainv (1 - x(k), n(k) / 2, m(k) / 2) - 1)
-                .* n(k) ./ m(k));
-    endif
+  k = (x >= 0) & (x < 1) & (m > 0) & (m < Inf) & (n > 0) & (n < Inf);
+  if (isscalar (m) && isscalar (n))
+    inv(k) = ((1 ./ betainv (1 - x(k), n/2, m/2) - 1) * n / m);
+  else
+    inv(k) = ((1 ./ betainv (1 - x(k), n(k)/2, m(k)/2) - 1)
+              .* n(k) ./ m(k));
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(finv (x, 2*ones(1,5), 2*ones(1,5)), [NaN 0 1 Inf NaN]);
+%!assert(finv (x, 2, 2*ones(1,5)), [NaN 0 1 Inf NaN]);
+%!assert(finv (x, 2*ones(1,5), 2), [NaN 0 1 Inf NaN]);
+%!assert(finv (x, [2 -Inf NaN Inf 2], 2), [NaN NaN NaN NaN NaN]);
+%!assert(finv (x, 2, [2 -Inf NaN Inf 2]), [NaN NaN NaN NaN NaN]);
+%!assert(finv ([x(1:2) NaN x(4:5)], 2, 2), [NaN 0 NaN Inf NaN]);
+
+%% Test class of input preserved
+%!assert(finv ([x, NaN], 2, 2), [NaN 0 1 Inf NaN NaN]);
+%!assert(finv (single([x, NaN]), 2, 2), single([NaN 0 1 Inf NaN NaN]));
+%!assert(finv ([x, NaN], single(2), 2), single([NaN 0 1 Inf NaN NaN]));
+%!assert(finv ([x, NaN], 2, single(2)), single([NaN 0 1 Inf NaN NaN]));
+
+%% Test input validation
+%!error finv ()
+%!error finv (1)
+%!error finv (1,2)
+%!error finv (1,2,3,4)
+%!error finv (ones(3),ones(2),ones(2))
+%!error finv (ones(2),ones(3),ones(2))
+%!error finv (ones(2),ones(2),ones(3))
+%!error finv (i, 2, 2)
+%!error finv (2, i, 2)
+%!error finv (2, 2, i)
+
--- a/scripts/statistics/distributions/fpdf.m
+++ b/scripts/statistics/distributions/fpdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -35,31 +36,70 @@
   if (!isscalar (m) || !isscalar (n))
     [retval, x, m, n] = common_size (x, m, n);
     if (retval > 0)
-      error ("fpdf: X, M and N must be of common size or scalar");
+      error ("fpdf: X, M, and N must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  pdf = zeros (sz);
+  if (iscomplex (x) || iscomplex (m) || iscomplex (n))
+    error ("fpdf: X, M, and N must not be complex");
+  endif

-  k = find (isnan (x) | !(m > 0) | !(n > 0));
-  if (any (k))
-    pdf(k) = NaN;
+  if (isa (x, "single") || isa (m, "single") || isa (n, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
   endif

-  k = find ((x > 0) & (x < Inf) & (m > 0) & (n > 0));
-  if (any (k))
-    if (isscalar (m) && isscalar (n))
-      tmp = m / n * x(k);
-      pdf(k) = (exp ((m / 2 - 1) .* log (tmp)
-                     - ((m + n) / 2) .* log (1 + tmp))
-                .* (m / n) ./ beta (m / 2, n / 2));
-    else
-      tmp = m(k) .* x(k) ./ n(k);
-      pdf(k) = (exp ((m(k) / 2 - 1) .* log (tmp)
-                     - ((m(k) + n(k)) / 2) .* log (1 + tmp))
-                .* (m(k) ./ n(k)) ./ beta (m(k) / 2, n(k) / 2));
-    endif
+  k = isnan (x) | !(m > 0) | !(m < Inf) | !(n > 0) | !(n < Inf);
+  pdf(k) = NaN;
+
+  k = (x > 0) & (x < Inf) & (m > 0) & (m < Inf) & (n > 0) & (n < Inf);
+  if (isscalar (m) && isscalar (n))
+    tmp = m / n * x(k);
+    pdf(k) = (exp ((m/2 - 1) * log (tmp)
+                   - ((m + n) / 2) * log (1 + tmp))
+              * (m / n) ./ beta (m/2, n/2));
+  else
+    tmp = m(k) .* x(k) ./ n(k);
+    pdf(k) = (exp ((m(k)/2 - 1) .* log (tmp)
+                   - ((m(k) + n(k)) / 2) .* log (1 + tmp))
+              .* (m(k) ./ n(k)) ./ beta (m(k)/2, n(k)/2));
   endif

 endfunction
+
+
+%% F (x, 1, m) == T distribution (sqrt (x), m) / sqrt (x)
+%!test
+%! x = rand (10,1);
+%! x = x(x > 0.1 & x < 0.9);
+%! y = tpdf (sqrt (x), 2) ./ sqrt (x);
+%! assert(fpdf (x, 1, 2), y, 5*eps);
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2];
+%! y = [0 0 4/9 1/4 1/9];
+%!assert(fpdf (x, 2*ones(1,5), 2*ones(1,5)), y, eps);
+%!assert(fpdf (x, 2, 2*ones(1,5)), y, eps);
+%!assert(fpdf (x, 2*ones(1,5), 2), y, eps);
+%!assert(fpdf (x, [0 NaN Inf 2 2], 2), [NaN NaN NaN y(4:5)], eps);
+%!assert(fpdf (x, 2, [0 NaN Inf 2 2]), [NaN NaN NaN y(4:5)], eps);
+%!assert(fpdf ([x, NaN], 2, 2), [y, NaN], eps);
+
+%% Test class of input preserved
+%!assert(fpdf (single([x, NaN]), 2, 2), single([y, NaN]), eps("single"));
+%!assert(fpdf ([x, NaN], single(2), 2), single([y, NaN]), eps("single"));
+%!assert(fpdf ([x, NaN], 2, single(2)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error fpdf ()
+%!error fpdf (1)
+%!error fpdf (1,2)
+%!error fpdf (1,2,3,4)
+%!error fpdf (ones(3),ones(2),ones(2))
+%!error fpdf (ones(2),ones(3),ones(2))
+%!error fpdf (ones(2),ones(2),ones(3))
+%!error fpdf (i, 2, 2)
+%!error fpdf (2, i, 2)
+%!error fpdf (2, 2, i)
+
--- a/scripts/statistics/distributions/frnd.m
+++ b/scripts/statistics/distributions/frnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,103 +18,115 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} frnd (@var{m}, @var{n}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} frnd (@var{m}, @var{n}, @var{sz})
-## Return an @var{r} by @var{c} matrix of random samples from the F
-## distribution with @var{m} and @var{n} degrees of freedom.  Both
-## @var{m} and @var{n} must be scalar or of size @var{r} by @var{c}.
-## If @var{sz} is a vector the random samples are in a matrix of
-## size @var{sz}.
+## @deftypefn  {Function File} {} frnd (@var{m}, @var{n})
+## @deftypefnx {Function File} {} frnd (@var{m}, @var{n}, @var{r})
+## @deftypefnx {Function File} {} frnd (@var{m}, @var{n}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} frnd (@var{m}, @var{n}, [@var{sz}])
+## Return a matrix of random samples from the F distribution with
+## @var{m} and @var{n} degrees of freedom.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{m} and @var{n}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{m} and @var{n}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the F distribution

-function rnd = frnd (m, n, r, c)
+function rnd = frnd (m, n, varargin)

-  if (nargin > 1)
-    if (!isscalar(m) || !isscalar(n))
-      [retval, m, n] = common_size (m, n);
-      if (retval > 0)
-        error ("frnd: M and N must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (m) || !isscalar (n))
+    [retval, m, n] = common_size (m, n);
+    if (retval > 0)
+      error ("frnd: M and N must be of common size or scalars");
     endif
   endif

-
-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("frnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("frnd: C must be a positive integer");
-    endif
-    sz = [r, c];
-
-    if (any (size (m) != 1)
-        && ((length (size (m)) != length (sz)) || any (size (m) != sz)))
-      error ("frnd: M and N must be scalar or of size [R,C]");
-    endif
-  elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("frnd: R must be a positive integer or vector");
-    endif
-
-    if (any (size (m) != 1)
-        && ((length (size (m)) != length (sz)) || any (size (m) != sz)))
-      error ("frnd: M and N must be scalar or of size SZ");
-    endif
-  elseif (nargin == 2)
-    sz = size(m);
-  else
-    print_usage ();
+  if (iscomplex (m) || iscomplex (n))
+    error ("frnd: M and N must not be complex");
   endif

+  if (nargin == 2)
+    sz = size (m);
+  elseif (nargin == 3)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("frnd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("frnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif
+
+  if (!isscalar (m) && !isequal (size (m), sz))
+    error ("frnd: M and N must be scalar or of size SZ");
+  endif
+
+  if (isa (m, "single") || isa (n, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif

   if (isscalar (m) && isscalar (n))
-    if (isinf (m) || isinf (n))
-      if (isinf (m))
-        rnd = ones (sz);
-      else
-        rnd = 2 ./ m .* randg(m / 2, sz);
-      endif
-      if (! isinf (n))
-        rnd = 0.5 .* n .* rnd ./ randg (n / 2, sz);
-      endif
-    elseif ((m > 0) && (m < Inf) && (n > 0) && (n < Inf))
-      rnd = n ./ m .* randg (m / 2, sz) ./ randg (n / 2, sz);
+    if ((m > 0) && (m < Inf) && (n > 0) && (n < Inf))
+      rnd = n/m * randg (m/2, sz) ./ randg (n/2, sz);
     else
-      rnd = NaN (sz);
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = zeros (sz);
-
-    k = find (isinf(m) | isinf(n));
-    if (any (k))
-      rnd (k) = 1;
-      k2 = find (!isinf(m) & isinf(n));
-      rnd (k2) = 2 ./ m(k2) .* randg (m(k2) ./ 2, size(k2));
-      k2 = find (isinf(m) & !isinf(n));
-      rnd (k2) = 0.5 .* n(k2) .* rnd(k2) ./ randg (n(k2) ./ 2, size(k2));
-    endif
+    rnd = NaN (sz, cls);

-    k = find (!(m > 0) | !(n > 0));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
-
-    k = find ((m > 0) & (m < Inf) &
-              (n > 0) & (n < Inf));
-    if (any (k))
-      rnd(k) = n(k) ./ m(k) .* randg(m(k)./2,size(k)) ./ randg(n(k)./2,size(k));
-    endif
+    k = (m > 0) & (m < Inf) & (n > 0) & (n < Inf);
+    rnd(k) = n(k) ./ m(k) .* randg (m(k)/2) ./ randg (n(k)/2);
   endif

 endfunction
+
+
+%!assert(size (frnd (1,2)), [1, 1]);
+%!assert(size (frnd (ones(2,1), 2)), [2, 1]);
+%!assert(size (frnd (ones(2,2), 2)), [2, 2]);
+%!assert(size (frnd (1, 2*ones(2,1))), [2, 1]);
+%!assert(size (frnd (1, 2*ones(2,2))), [2, 2]);
+%!assert(size (frnd (1, 2, 3)), [3, 3]);
+%!assert(size (frnd (1, 2, [4 1])), [4, 1]);
+%!assert(size (frnd (1, 2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (frnd (1, 2)), "double");
+%!assert(class (frnd (single(1), 2)), "single");
+%!assert(class (frnd (single([1 1]), 2)), "single");
+%!assert(class (frnd (1, single(2))), "single");
+%!assert(class (frnd (1, single([2 2]))), "single");
+
+%% Test input validation
+%!error frnd ()
+%!error frnd (1)
+%!error frnd (ones(3),ones(2))
+%!error frnd (ones(2),ones(3))
+%!error frnd (i, 2)
+%!error frnd (2, i)
+%!error frnd (1,2, -1)
+%!error frnd (1,2, ones(2))
+%!error frnd (1, 2, [2 -1 2])
+%!error frnd (1,2, 1, ones(2))
+%!error frnd (1,2, 1, -1)
+%!error frnd (ones(2,2), 2, 3)
+%!error frnd (ones(2,2), 2, [3, 2])
+%!error frnd (ones(2,2), 2, 2, 3)
+
--- a/scripts/statistics/distributions/gamcdf.m
+++ b/scripts/statistics/distributions/gamcdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -21,7 +22,6 @@
 ## For each element of @var{x}, compute the cumulative distribution
 ## function (CDF) at @var{x} of the Gamma distribution with parameters
 ## @var{a} and @var{b}.
-## @seealso{gamma, gammaln, gammainc, gampdf, gaminv, gamrnd}
 ## @end deftypefn

 ## Author: TT <Teresa.Twaroch@ci.tuwien.ac.at>
@@ -33,28 +33,59 @@
     print_usage ();
   endif

-  if (!isscalar (a) || !isscalar(b))
+  if (!isscalar (a) || !isscalar (b))
     [retval, x, a, b] = common_size (x, a, b);
     if (retval > 0)
-      error ("gamcdf: X, A and B must be of common size or scalars");
+      error ("gamcdf: X, A, and B must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  cdf = zeros (sz);
-
-  k = find (!(a > 0) | !(b > 0) | isnan (x));
-  if (any (k))
-    cdf (k) = NaN;
+  if (iscomplex (x) || iscomplex (a) || iscomplex (b))
+    error ("gamcdf: X, A, and B must not be complex");
   endif

-  k = find ((x > 0) & (a > 0) & (b > 0));
-  if (any (k))
-    if (isscalar (a) && isscalar(b))
-      cdf (k) = gammainc (x(k) ./ b, a);
-    else
-      cdf (k) = gammainc (x(k) ./ b(k), a(k));
-    endif
+  if (isa (x, "single") || isa (a, "single") || isa (b, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
+  endif
+
+  k = isnan (x) | !(a > 0) | !(a < Inf) | !(b > 0) | !(b < Inf);
+  cdf(k) = NaN;
+
+  k = (x > 0) & (a > 0) & (a < Inf) & (b > 0) & (b < Inf);
+  if (isscalar (a) && isscalar (b))
+    cdf(k) = gammainc (x(k) / b, a);
+  else
+    cdf(k) = gammainc (x(k) ./ b(k), a(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2 Inf];
+%! y = [0, gammainc(x(2:end), 1)];
+%!assert(gamcdf (x, ones(1,6), ones(1,6)), y);
+%!assert(gamcdf (x, 1, ones(1,6)), y);
+%!assert(gamcdf (x, ones(1,6), 1), y);
+%!assert(gamcdf (x, [0 -Inf NaN Inf 1 1], 1), [NaN NaN NaN NaN y(5:6)]);
+%!assert(gamcdf (x, 1, [0 -Inf NaN Inf 1 1]), [NaN NaN NaN NaN y(5:6)]);
+%!assert(gamcdf ([x(1:2) NaN x(4:6)], 1, 1), [y(1:2) NaN y(4:6)]);
+
+%% Test class of input preserved
+%!assert(gamcdf ([x, NaN], 1, 1), [y, NaN]);
+%!assert(gamcdf (single([x, NaN]), 1, 1), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error gamcdf ()
+%!error gamcdf (1)
+%!error gamcdf (1,2)
+%!error gamcdf (1,2,3,4)
+%!error gamcdf (ones(3),ones(2),ones(2))
+%!error gamcdf (ones(2),ones(3),ones(2))
+%!error gamcdf (ones(2),ones(2),ones(3))
+%!error gamcdf (i, 2, 2)
+%!error gamcdf (2, i, 2)
+%!error gamcdf (2, 2, i)
+
--- a/scripts/statistics/distributions/gaminv.m
+++ b/scripts/statistics/distributions/gaminv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,10 +19,9 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} gaminv (@var{x}, @var{a}, @var{b})
-## For each component of @var{x}, compute the quantile (the inverse of
+## For each element of @var{x}, compute the quantile (the inverse of
 ## the CDF) at @var{x} of the Gamma distribution with parameters @var{a}
 ## and @var{b}.
-## @seealso{gamma, gammaln, gammainc, gampdf, gamcdf, gamrnd}
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -33,36 +33,40 @@
     print_usage ();
   endif

-  if (!isscalar (a) || !isscalar(b))
+  if (!isscalar (a) || !isscalar (b))
     [retval, x, a, b] = common_size (x, a, b);
     if (retval > 0)
-      error ("gaminv: X, A and B must be of common size or scalars");
+      error ("gaminv: X, A, and B must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  inv = zeros (sz);
+  if (iscomplex (x) || iscomplex (a) || iscomplex (b))
+    error ("gaminv: X, A, and B must not be complex");
+  endif

-  k = find ((x < 0) | (x > 1) | isnan (x) | !(a > 0) | !(b > 0));
-  if (any (k))
-    inv (k) = NaN;
+  if (isa (x, "single") || isa (a, "single") || isa (b, "single"))
+    inv = zeros (size (x), "single");
+  else
+    inv = zeros (size (x));
   endif

-  k = find ((x == 1) & (a > 0) & (b > 0));
-  if (any (k))
-    inv (k) = Inf;
-  endif
+  k = ((x < 0) | (x > 1) | isnan (x)
+       | !(a > 0) | !(a < Inf) | !(b > 0) | !(b < Inf));
+  inv(k) = NaN;

-  k = find ((x > 0) & (x < 1) & (a > 0) & (b > 0));
+  k = (x == 1) & (a > 0) & (a < Inf) & (b > 0) & (b < Inf);
+  inv(k) = Inf;
+
+  k = find ((x > 0) & (x < 1) & (a > 0) & (a < Inf) & (b > 0) & (b < Inf));
   if (any (k))
-    if (!isscalar(a) || !isscalar(b))
-      a = a (k);
-      b = b (k);
+    if (!isscalar (a) || !isscalar (b))
+      a = a(k);
+      b = b(k);
       y = a .* b;
     else
       y = a * b * ones (size (k));
     endif
-    x = x (k);
+    x = x(k);

     if (isa (x, "single"))
       myeps = eps ("single");
@@ -90,7 +94,36 @@
       y_old = y_new;
     endfor

-    inv (k) = y_new;
+    inv(k) = y_new;
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.63212055882855778 1 2];
+%!assert(gaminv (x, ones(1,5), ones(1,5)), [NaN 0 1 Inf NaN], eps);
+%!assert(gaminv (x, 1, ones(1,5)), [NaN 0 1 Inf NaN], eps);
+%!assert(gaminv (x, ones(1,5), 1), [NaN 0 1 Inf NaN], eps);
+%!assert(gaminv (x, [1 -Inf NaN Inf 1], 1), [NaN NaN NaN NaN NaN]);
+%!assert(gaminv (x, 1, [1 -Inf NaN Inf 1]), [NaN NaN NaN NaN NaN]);
+%!assert(gaminv ([x(1:2) NaN x(4:5)], 1, 1), [NaN 0 NaN Inf NaN]);
+
+%% Test class of input preserved
+%!assert(gaminv ([x, NaN], 1, 1), [NaN 0 1 Inf NaN NaN], eps);
+%!assert(gaminv (single([x, NaN]), 1, 1), single([NaN 0 1 Inf NaN NaN]), eps("single"));
+%!assert(gaminv ([x, NaN], single(1), 1), single([NaN 0 1 Inf NaN NaN]), eps("single"));
+%!assert(gaminv ([x, NaN], 1, single(1)), single([NaN 0 1 Inf NaN NaN]), eps("single"));
+
+%% Test input validation
+%!error gaminv ()
+%!error gaminv (1)
+%!error gaminv (1,2)
+%!error gaminv (1,2,3,4)
+%!error gaminv (ones(3),ones(2),ones(2))
+%!error gaminv (ones(2),ones(3),ones(2))
+%!error gaminv (ones(2),ones(2),ones(3))
+%!error gaminv (i, 2, 2)
+%!error gaminv (2, i, 2)
+%!error gaminv (2, 2, i)
+
--- a/scripts/statistics/distributions/gampdf.m
+++ b/scripts/statistics/distributions/gampdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -21,7 +22,6 @@
 ## For each element of @var{x}, return the probability density function
 ## (PDF) at @var{x} of the Gamma distribution with parameters @var{a}
 ## and @var{b}.
-## @seealso{gamma, gammaln, gammainc, gamcdf, gaminv, gamrnd}
 ## @end deftypefn

 ## Author: TT <Teresa.Twaroch@ci.tuwien.ac.at>
@@ -33,41 +33,71 @@
     print_usage ();
   endif

-  if (!isscalar (a) || !isscalar(b))
+  if (!isscalar (a) || !isscalar (b))
     [retval, x, a, b] = common_size (x, a, b);
     if (retval > 0)
-      error ("gampdf: X, A and B must be of common size or scalars");
+      error ("gampdf: X, A, and B must be of common size or scalars");
     endif
   endif

-  sz = size(x);
-  pdf = zeros (sz);
+  if (iscomplex (x) || iscomplex (a) || iscomplex (b))
+    error ("gampdf: X, A, and B must not be complex");
+  endif

-  k = find (!(a > 0) | !(b > 0) | isnan (x));
-  if (any (k))
-    pdf (k) = NaN;
+  if (isa (x, "single") || isa (a, "single") || isa (b, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
   endif

-  k = find ((x >= 0) & (a > 0) & (a <= 1) & (b > 0));
-  if (any (k))
-    if (isscalar(a) && isscalar(b))
-      pdf(k) = (x(k) .^ (a - 1)) ...
-                .* exp(- x(k) ./ b) ./ gamma (a) ./ (b .^ a);
-    else
-      pdf(k) = (x(k) .^ (a(k) - 1)) ...
-                .* exp(- x(k) ./ b(k)) ./ gamma (a(k)) ./ (b(k) .^ a(k));
-    endif
+  k = !(a > 0) | !(b > 0) | isnan (x);
+  pdf(k) = NaN;
+
+  k = (x >= 0) & (a > 0) & (a <= 1) & (b > 0);
+  if (isscalar (a) && isscalar (b))
+    pdf(k) = (x(k) .^ (a - 1)) ...
+              .* exp (- x(k) / b) / gamma (a) / (b ^ a);
+  else
+    pdf(k) = (x(k) .^ (a(k) - 1)) ...
+              .* exp (- x(k) ./ b(k)) ./ gamma (a(k)) ./ (b(k) .^ a(k));
   endif

-  k = find ((x >= 0) & (a > 1) & (b > 0));
-  if (any (k))
-    if (isscalar(a) && isscalar(b))
-      pdf(k) = exp (- a .* log (b) + (a-1) .* log (x(k))
-                    - x(k) ./ b - gammaln (a));
-    else
-      pdf(k) = exp (- a(k) .* log (b(k)) + (a(k)-1) .* log (x(k))
-                    - x(k) ./ b(k) - gammaln (a(k)));
-    endif
+  k = (x >= 0) & (a > 1) & (b > 0);
+  if (isscalar (a) && isscalar (b))
+    pdf(k) = exp (- a * log (b) + (a-1) * log (x(k))
+                  - x(k) / b - gammaln (a));
+  else
+    pdf(k) = exp (- a(k) .* log (b(k)) + (a(k)-1) .* log (x(k))
+                  - x(k) ./ b(k) - gammaln (a(k)));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 Inf];
+%! y = [0 exp(-x(2:end))];
+%!assert(gampdf (x, ones(1,5), ones(1,5)), y);
+%!assert(gampdf (x, 1, ones(1,5)), y);
+%!assert(gampdf (x, ones(1,5), 1), y);
+%!assert(gampdf (x, [0 -Inf NaN Inf 1], 1), [NaN NaN NaN NaN y(5)]);
+%!assert(gampdf (x, 1, [0 -Inf NaN Inf 1]), [NaN NaN NaN 0 y(5)]);
+%!assert(gampdf ([x, NaN], 1, 1), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(gampdf (single([x, NaN]), 1, 1), single([y, NaN]));
+%!assert(gampdf ([x, NaN], single(1), 1), single([y, NaN]));
+%!assert(gampdf ([x, NaN], 1, single(1)), single([y, NaN]));
+
+%% Test input validation
+%!error gampdf ()
+%!error gampdf (1)
+%!error gampdf (1,2)
+%!error gampdf (1,2,3,4)
+%!error gampdf (ones(3),ones(2),ones(2))
+%!error gampdf (ones(2),ones(3),ones(2))
+%!error gampdf (ones(2),ones(2),ones(3))
+%!error gampdf (i, 2, 2)
+%!error gampdf (2, i, 2)
+%!error gampdf (2, 2, i)
+
--- a/scripts/statistics/distributions/gamrnd.m
+++ b/scripts/statistics/distributions/gamrnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,81 +18,118 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} gamrnd (@var{a}, @var{b}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} gamrnd (@var{a}, @var{b}, @var{sz})
-## Return an @var{r} by @var{c} or a @code{size (@var{sz})} matrix of
-## random samples from the Gamma distribution with parameters @var{a}
-## and @var{b}.  Both @var{a} and @var{b} must be scalar or of size
-## @var{r} by @var{c}.
+## @deftypefn  {Function File} {} gamrnd (@var{a}, @var{b})
+## @deftypefnx {Function File} {} gamrnd (@var{a}, @var{b}, @var{r})
+## @deftypefnx {Function File} {} gamrnd (@var{a}, @var{b}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} gamrnd (@var{a}, @var{b}, [@var{sz}])
+## Return a matrix of random samples from the Gamma distribution with
+## parameters @var{a} and @var{b}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{a} and @var{b}.
-## @seealso{gamma, gammaln, gammainc, gampdf, gamcdf, gaminv}
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{a} and @var{b}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the Gamma distribution

-function rnd = gamrnd (a, b, r, c)
+function rnd = gamrnd (a, b, varargin)

-  if (nargin > 1)
-    if (!isscalar(a) || !isscalar(b))
-      [retval, a, b] = common_size (a, b);
-      if (retval > 0)
-        error ("gamrnd: A and B must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (a) || !isscalar (b))
+    [retval, a, b] = common_size (a, b);
+    if (retval > 0)
+      error ("gamrnd: A and B must be of common size or scalars");
     endif
   endif

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("gamrnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("gamrnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+  if (iscomplex (a) || iscomplex (b))
+    error ("gamrnd: A and B must not be complex");
+  endif

-    if (any (size (a) != 1)
-        && (length (size (a)) != length (sz) || any (size (a) != sz)))
-      error ("gamrnd: A and B must be scalar or of size [R, C]");
-    endif
+  if (nargin == 2)
+    sz = size (a);
   elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      error ("gamrnd: R must be a positive integer or vector");
+      error ("gamrnd: dimension vector must be row vector of non-negative integers");
     endif
-
-    if (any (size (a) != 1)
-        && (length (size (a)) != length (sz) || any (size (a) != sz)))
-      error ("gamrnd: A and B must be scalar or of size SZ");
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("gamrnd: dimensions must be non-negative integers");
     endif
-  elseif (nargin == 2)
-    sz = size(a);
-  else
-    print_usage ();
+    sz = [varargin{:}];
   endif

-  rnd = zeros (sz);
+  if (!isscalar (a) && !isequal (size (a), sz))
+    error ("gamrnd: A and B must be scalar or of size SZ");
+  endif

-  if (isscalar (a) && isscalar(b))
-    if (find (!(a > 0) | !(a < Inf) | !(b > 0) | !(b < Inf)))
-      rnd = NaN (sz);
-    else
-      rnd = b .* randg(a, sz);
+  if (isa (a, "single") || isa (b, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif
+
+  if (isscalar (a) && isscalar (b))
+    if ((a > 0) && (a < Inf) && (b > 0) && (b < Inf))
+      rnd = b * randg (a, sz);
+      if (strcmp (cls, "single"))
+        rnd = single (rnd);
+      endif
+    else
+      rnd = NaN (sz, cls);
     endif
   else
-    k = find (!(a > 0) | !(a < Inf) | !(b > 0) | !(b < Inf));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
-    k = find ((a > 0) & (a < Inf) & (b > 0) & (b < Inf));
-    if (any (k))
-      rnd(k) = b(k) .* randg(a(k), size(k));
-    endif
+    rnd = NaN (sz, cls);
+
+    k = (a > 0) & (a < Inf) & (b > 0) & (b < Inf);
+    rnd(k) = b(k) .* randg (a(k));
   endif

 endfunction
+
+
+%!assert(size (gamrnd (1,2)), [1, 1]);
+%!assert(size (gamrnd (ones(2,1), 2)), [2, 1]);
+%!assert(size (gamrnd (ones(2,2), 2)), [2, 2]);
+%!assert(size (gamrnd (1, 2*ones(2,1))), [2, 1]);
+%!assert(size (gamrnd (1, 2*ones(2,2))), [2, 2]);
+%!assert(size (gamrnd (1, 2, 3)), [3, 3]);
+%!assert(size (gamrnd (1, 2, [4 1])), [4, 1]);
+%!assert(size (gamrnd (1, 2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (gamrnd (1, 2)), "double");
+%!assert(class (gamrnd (single(1), 2)), "single");
+%!assert(class (gamrnd (single([1 1]), 2)), "single");
+%!assert(class (gamrnd (1, single(2))), "single");
+%!assert(class (gamrnd (1, single([2 2]))), "single");
+
+%% Test input validation
+%!error gamrnd ()
+%!error gamrnd (1)
+%!error gamrnd (ones(3),ones(2))
+%!error gamrnd (ones(2),ones(3))
+%!error gamrnd (i, 2)
+%!error gamrnd (2, i)
+%!error gamrnd (1,2, -1)
+%!error gamrnd (1,2, ones(2))
+%!error gamrnd (1, 2, [2 -1 2])
+%!error gamrnd (1,2, 1, ones(2))
+%!error gamrnd (1,2, 1, -1)
+%!error gamrnd (ones(2,2), 2, 3)
+%!error gamrnd (ones(2,2), 2, [3, 2])
+%!error gamrnd (ones(2,2), 2, 2, 3)
+
--- a/scripts/statistics/distributions/geocdf.m
+++ b/scripts/statistics/distributions/geocdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,8 +19,8 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} geocdf (@var{x}, @var{p})
-## For each element of @var{x}, compute the CDF at @var{x} of the
-## geometric distribution with parameter @var{p}.
+## For each element of @var{x}, compute the cumulative distribution function
+## (CDF) at @var{x} of the geometric distribution with parameter @var{p}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -31,34 +32,58 @@
     print_usage ();
   endif

-  if (!isscalar (x) && !isscalar (p))
+  if (!isscalar (p))
     [retval, x, p] = common_size (x, p);
     if (retval > 0)
-      error ("geocdf: X and P must be of common size or scalar");
+      error ("geocdf: X and P must be of common size or scalars");
     endif
   endif

-  cdf = zeros (size (x));
+  if (iscomplex (x) || iscomplex (p))
+    error ("geocdf: X and P must not be complex");
+  endif

-  k = find (isnan (x) | !(p >= 0) | !(p <= 1));
-  if (any (k))
-    cdf(k) = NaN;
+  if (isa (x, "single") || isa (p, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x == Inf) & (p >= 0) & (p <= 1));
-  if (any (k))
-    cdf(k) = 1;
-  endif
+  k = isnan (x) | !(p >= 0) | !(p <= 1);
+  cdf(k) = NaN;
+
+  k = (x == Inf) & (p >= 0) & (p <= 1);
+  cdf(k) = 1;

-  k = find ((x >= 0) & (x < Inf) & (x == round (x)) & (p > 0) & (p <= 1));
-  if (any (k))
-    if (isscalar (x))
-      cdf(k) = 1 - ((1 - p(k)) .^ (x + 1));
-    elseif (isscalar (p))
-      cdf(k) = 1 - ((1 - p) .^ (x(k) + 1));
-    else
-      cdf(k) = 1 - ((1 - p(k)) .^ (x(k) + 1));
-    endif
+  k = (x >= 0) & (x < Inf) & (x == fix (x)) & (p > 0) & (p <= 1);
+  if (isscalar (p))
+    cdf(k) = 1 - ((1 - p) .^ (x(k) + 1));
+  else
+    cdf(k) = 1 - ((1 - p(k)) .^ (x(k) + 1));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 Inf];
+%! y = [0 0.5 0.75 1];
+%!assert(geocdf (x, 0.5*ones(1,4)), y);
+%!assert(geocdf (x, 0.5), y);
+%!assert(geocdf (x, 0.5*[-1 NaN 4 1]), [NaN NaN NaN y(4)]);
+%!assert(geocdf ([x(1:2) NaN x(4)], 0.5), [y(1:2) NaN y(4)]);
+
+%% Test class of input preserved
+%!assert(geocdf ([x, NaN], 0.5), [y, NaN]);
+%!assert(geocdf (single([x, NaN]), 0.5), single([y, NaN]));
+%!assert(geocdf ([x, NaN], single(0.5)), single([y, NaN]));
+
+%% Test input validation
+%!error geocdf ()
+%!error geocdf (1)
+%!error geocdf (1,2,3)
+%!error geocdf (ones(3),ones(2))
+%!error geocdf (ones(2),ones(3))
+%!error geocdf (i, 2)
+%!error geocdf (2, i)
+
--- a/scripts/statistics/distributions/geoinv.m
+++ b/scripts/statistics/distributions/geoinv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,8 +19,8 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} geoinv (@var{x}, @var{p})
-## For each element of @var{x}, compute the quantile at @var{x} of the
-## geometric distribution with parameter @var{p}.
+## For each element of @var{x}, compute the quantile (the inverse of
+## the CDF) at @var{x} of the geometric distribution with parameter @var{p}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -31,34 +32,54 @@
     print_usage ();
   endif

-  if (!isscalar (x) && !isscalar (p))
+  if (!isscalar (p))
     [retval, x, p] = common_size (x, p);
     if (retval > 0)
-      error ("geoinv: X and P must be of common size or scalar");
+      error ("geoinv: X and P must be of common size or scalars");
     endif
   endif

-  inv = zeros (size (x));
-
-  k = find (!(x >= 0) | !(x <= 1) | !(p >= 0) | !(p <= 1));
-  if (any (k))
-    inv(k) = NaN;
+  if (iscomplex (x) || iscomplex (p))
+    error ("geoinv: X and P must not be complex");
   endif

-  k = find ((x == 1) & (p >= 0) & (p <= 1));
-  if (any (k))
-    inv(k) = Inf;
+  if (isa (x, "single") || isa (p, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  k = find ((x > 0) & (x < 1) & (p > 0) & (p <= 1));
-  if (any (k))
-    if (isscalar (x))
-      inv(k) = max (ceil (log (1 - x) ./ log (1 - p(k))) - 1, 0);
-    elseif (isscalar (p))
-      inv(k) = max (ceil (log (1 - x(k)) / log (1 - p)) - 1, 0);
-    else
-      inv(k) = max (ceil (log (1 - x(k)) ./ log (1 - p(k))) - 1, 0);
-    endif
+  k = (x == 1) & (p >= 0) & (p <= 1);
+  inv(k) = Inf;
+
+  k = (x >= 0) & (x < 1) & (p > 0) & (p <= 1);
+  if (isscalar (p))
+    inv(k) = max (ceil (log (1 - x(k)) / log (1 - p)) - 1, 0);
+  else
+    inv(k) = max (ceil (log (1 - x(k)) ./ log (1 - p(k))) - 1, 0);
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.75 1 2];
+%!assert(geoinv (x, 0.5*ones(1,5)), [NaN 0 1 Inf NaN]);
+%!assert(geoinv (x, 0.5), [NaN 0 1 Inf NaN]);
+%!assert(geoinv (x, 0.5*[1 -1 NaN 4 1]), [NaN NaN NaN NaN NaN]);
+%!assert(geoinv ([x(1:2) NaN x(4:5)], 0.5), [NaN 0 NaN Inf NaN]);
+
+%% Test class of input preserved
+%!assert(geoinv ([x, NaN], 0.5), [NaN 0 1 Inf NaN NaN]);
+%!assert(geoinv (single([x, NaN]), 0.5), single([NaN 0 1 Inf NaN NaN]));
+%!assert(geoinv ([x, NaN], single(0.5)), single([NaN 0 1 Inf NaN NaN]));
+
+%% Test input validation
+%!error geoinv ()
+%!error geoinv (1)
+%!error geoinv (1,2,3)
+%!error geoinv (ones(3),ones(2))
+%!error geoinv (ones(2),ones(3))
+%!error geoinv (i, 2)
+%!error geoinv (2, i)
+
--- a/scripts/statistics/distributions/geopdf.m
+++ b/scripts/statistics/distributions/geopdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -31,35 +32,54 @@
     print_usage ();
   endif

-  if (!isscalar (x) && !isscalar (p))
+  if (!isscalar (p))
     [retval, x, p] = common_size (x, p);
     if (retval > 0)
-      error ("geopdf: X and P must be of common size or scalar");
+      error ("geopdf: X and P must be of common size or scalars");
     endif
   endif

-  pdf = zeros (size (x));
-
-  k = find (isnan (x) | !(p >= 0) | !(p <= 1));
-  if (any (k))
-    pdf(k) = NaN;
+  if (iscomplex (x) || iscomplex (p))
+    error ("geopdf: X and P must not be complex");
   endif

-  ## Just for the fun of it ...
-  k = find ((x == Inf) & (p == 0));
-  if (any (k))
-    pdf(k) = 1;
+  if (isa (x, "single") || isa (p, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
   endif

-  k = find ((x >= 0) & (x < Inf) & (x == round (x)) & (p > 0) & (p <= 1));
-  if (any (k))
-    if (isscalar (x))
-      pdf(k) = p(k) .* ((1 - p(k)) .^ x);
-    elseif (isscalar (p))
-      pdf(k) = p .* ((1 - p) .^ x(k));
-    else
-      pdf(k) = p(k) .* ((1 - p(k)) .^ x(k));
-    endif
+  k = isnan (x) | (x == Inf) | !(p >= 0) | !(p <= 1);
+  pdf(k) = NaN;
+
+  k = (x >= 0) & (x < Inf) & (x == fix (x)) & (p > 0) & (p <= 1);
+  if (isscalar (p))
+    pdf(k) = p * ((1 - p) .^ x(k));
+  else
+    pdf(k) = p(k) .* ((1 - p(k)) .^ x(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 Inf];
+%! y = [0, 1/2, 1/4, NaN];
+%!assert(geopdf (x, 0.5*ones(1,4)), y);
+%!assert(geopdf (x, 0.5), y);
+%!assert(geopdf (x, 0.5*[-1 NaN 4 1]), [NaN NaN NaN y(4)]);
+%!assert(geopdf ([x, NaN], 0.5), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(geopdf (single([x, NaN]), 0.5), single([y, NaN]), 5*eps("single"));
+%!assert(geopdf ([x, NaN], single(0.5)), single([y, NaN]), 5*eps("single"));
+
+%% Test input validation
+%!error geopdf ()
+%!error geopdf (1)
+%!error geopdf (1,2,3)
+%!error geopdf (ones(3),ones(2))
+%!error geopdf (ones(2),ones(3))
+%!error geopdf (i, 2)
+%!error geopdf (2, i)
+
--- a/scripts/statistics/distributions/geornd.m
+++ b/scripts/statistics/distributions/geornd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,77 +18,108 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} geornd (@var{p}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} geornd (@var{p}, @var{sz})
-## Return an @var{r} by @var{c} matrix of random samples from the
-## geometric distribution with parameter @var{p}, which must be a scalar
-## or of size @var{r} by @var{c}.
+## @deftypefn  {Function File} {} geornd (@var{p})
+## @deftypefnx {Function File} {} geornd (@var{p}, @var{r})
+## @deftypefnx {Function File} {} geornd (@var{p}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} geornd (@var{p}, [@var{sz}])
+## Return a matrix of random samples from the geometric distribution with
+## parameter @var{p}.
 ##
-## If @var{r} and @var{c} are given create a matrix with @var{r} rows and
-## @var{c} columns.  Or if @var{sz} is a vector, create a matrix of size
-## @var{sz}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the size of
+## @var{p}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the geometric distribution

-function rnd = geornd (p, r, c)
-
-  if (nargin == 3)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("geornd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("geornd: C must be a positive integer");
-    endif
-    sz = [r, c];
+function rnd = geornd (p, varargin)

-    if (any (size (p) != 1)
-        && ((length (size (p)) != length (sz)) || any (size (p) != sz)))
-      error ("geornd: P must be scalar or of size [R, C]");
-    endif
-  elseif (nargin == 2)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("geornd: R must be a positive integer or vector");
-    endif
-
-    if (any (size (p) != 1)
-        && ((length (size (p)) != length (sz)) || any (size (p) != sz)))
-      error ("geornd: n must be scalar or of size SZ");
-    endif
-  elseif (nargin == 1)
-    sz = size(p);
-  elseif (nargin != 1)
+  if (nargin < 1)
     print_usage ();
   endif

+  if (nargin == 1)
+    sz = size (p);
+  elseif (nargin == 2)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("geornd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 2)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("geornd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif
+
+  if (!isscalar (p) && !isequal (size (p), sz))
+    error ("geornd: P must be scalar or of size SZ");
+  endif
+
+  if (iscomplex (p))
+    error ("geornd: P must not be complex");
+  endif
+
+  if (isa (p, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif

   if (isscalar (p))
-    if (p < 0 || p > 1)
-      rnd = NaN (sz);
+    if (p > 0 && p < 1);
+      rnd = floor (- rande (sz) ./ log (1 - p));
     elseif (p == 0)
-      rnd = Inf (sz);
-    elseif (p > 0 && p < 1);
-      rnd = floor (- rande(sz) ./ log (1 - p));
-    else
-      rnd = zeros (sz);
+      rnd = Inf (sz, cls);
+    elseif (p == 1)
+      rnd = zeros (sz, cls);
+    elseif (p < 0 || p > 1)
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = floor (- rande(sz) ./ log (1 - p));
+    rnd = floor (- rande (sz) ./ log (1 - p));

-    k = find (!(p >= 0) | !(p <= 1));
-    if (any (k))
-      rnd(k) = NaN (1, length (k));
-    endif
+    k = !(p >= 0) | !(p <= 1);
+  rnd(k) = NaN;

-    k = find (p == 0);
-    if (any (k))
-      rnd(k) = Inf (1, length (k));
-    endif
+    k = (p == 0);
+    rnd(k) = Inf;
   endif

 endfunction
+
+
+%!assert(size (geornd (0.5)), [1, 1]);
+%!assert(size (geornd (0.5*ones(2,1))), [2, 1]);
+%!assert(size (geornd (0.5*ones(2,2))), [2, 2]);
+%!assert(size (geornd (0.5, 3)), [3, 3]);
+%!assert(size (geornd (0.5, [4 1])), [4, 1]);
+%!assert(size (geornd (0.5, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (geornd (0.5)), "double");
+%!assert(class (geornd (single(0.5))), "single");
+%!assert(class (geornd (single([0.5 0.5]))), "single");
+%!assert(class (geornd (single(0))), "single");
+%!assert(class (geornd (single(1))), "single");
+
+%% Test input validation
+%!error geornd ()
+%!error geornd (ones(3),ones(2))
+%!error geornd (ones(2),ones(3))
+%!error geornd (i)
+%!error geornd (1, -1)
+%!error geornd (1, ones(2))
+%!error geornd (1, [2 -1 2])
+%!error geornd (ones(2,2), 2, 3)
+%!error geornd (ones(2,2), 3, 2)
+
--- a/scripts/statistics/distributions/hygecdf.m
+++ b/scripts/statistics/distributions/hygecdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1997-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -25,7 +26,7 @@
 ## replacement from a population of total size @var{t} containing
 ## @var{m} marked items.
 ##
-## The parameters @var{t}, @var{m}, and @var{n} must positive integers
+## The parameters @var{t}, @var{m}, and @var{n} must be positive integers
 ## with @var{m} and @var{n} not greater than @var{t}.
 ## @end deftypefn

@@ -39,14 +40,70 @@
   endif

   if (!isscalar (t) || !isscalar (m) || !isscalar (n))
-    error ("hygecdf: T, M and N must all be positive integers");
+    [retval, x, t, m, n] = common_size (x, t, m, n);
+    if (retval > 0)
+      error ("hygecdf: X, T, M, and N must be of common size or scalars");
+    endif
+  endif
+
+  if (iscomplex (x) || iscomplex (t) || iscomplex (m) || iscomplex (n))
+    error ("hygecdf: X, T, M, and N must not be complex");
   endif

-  if (t < 0 || m < 0 || n <= 0 || t != round (t) || m != round (m)
-      || n != round (n) || m > t || n > t)
+  if (isa (x, "single") || isa (t, "single") || isa (m, "single") || isa (n, "single"))
+    cdf = NaN (size (x), "single");
+  else
     cdf = NaN (size (x));
+  endif
+
+  ok = ((t >= 0) & (m >= 0) & (n > 0) & (m <= t) & (n <= t) &
+        (t == fix (t)) & (m == fix (m)) & (n == fix (n)));
+
+  if (isscalar (t))
+    if (ok)
+      cdf = discrete_cdf (x, 0 : n, hygepdf (0 : n, t, m, n));
+    endif
   else
-    cdf = discrete_cdf (x, 0 : n, hygepdf (0 : n, t, m, n));
+    for i = find (ok(:)')  # Must be row vector arg to for loop
+      v = 0 : n(i);
+      cdf(i) = discrete_cdf (x(i), v, hygepdf (v, t(i), m(i), n(i)));
+    endfor
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 2 3];
+%! y = [0 1/6 5/6 1 1];
+%!assert(hygecdf (x, 4*ones(1,5), 2, 2), y, eps);
+%!assert(hygecdf (x, 4, 2*ones(1,5), 2), y, eps);
+%!assert(hygecdf (x, 4, 2, 2*ones(1,5)), y, eps);
+%!assert(hygecdf (x, 4*[1 -1 NaN 1.1 1], 2, 2), [y(1) NaN NaN NaN y(5)], eps);
+%!assert(hygecdf (x, 4, 2*[1 -1 NaN 1.1 1], 2), [y(1) NaN NaN NaN y(5)], eps);
+%!assert(hygecdf (x, 4, 5, 2), [NaN NaN NaN NaN NaN]);
+%!assert(hygecdf (x, 4, 2, 2*[1 -1 NaN 1.1 1]), [y(1) NaN NaN NaN y(5)], eps);
+%!assert(hygecdf (x, 4, 2, 5), [NaN NaN NaN NaN NaN]);
+%!assert(hygecdf ([x(1:2) NaN x(4:5)], 4, 2, 2), [y(1:2) NaN y(4:5)], eps);
+
+%% Test class of input preserved
+%!assert(hygecdf ([x, NaN], 4, 2, 2), [y, NaN], eps);
+%!assert(hygecdf (single([x, NaN]), 4, 2, 2), single([y, NaN]), eps("single"));
+%!assert(hygecdf ([x, NaN], single(4), 2, 2), single([y, NaN]), eps("single"));
+%!assert(hygecdf ([x, NaN], 4, single(2), 2), single([y, NaN]), eps("single"));
+%!assert(hygecdf ([x, NaN], 4, 2, single(2)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error hygecdf ()
+%!error hygecdf (1)
+%!error hygecdf (1,2)
+%!error hygecdf (1,2,3)
+%!error hygecdf (1,2,3,4,5)
+%!error hygecdf (ones(2), ones(3), 1, 1)
+%!error hygecdf (1, ones(2), ones(3), 1)
+%!error hygecdf (1, 1, ones(2), ones(3))
+%!error hygecdf (i, 2, 2, 2)
+%!error hygecdf (2, i, 2, 2)
+%!error hygecdf (2, 2, i, 2)
+%!error hygecdf (2, 2, 2, i)
+
--- a/scripts/statistics/distributions/hygeinv.m
+++ b/scripts/statistics/distributions/hygeinv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1997-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,11 +19,14 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} hygeinv (@var{x}, @var{t}, @var{m}, @var{n})
-## For each element of @var{x}, compute the quantile at @var{x} of the
-## hypergeometric distribution with parameters @var{t}, @var{m}, and
-## @var{n}.
+## For each element of @var{x}, compute the quantile (the inverse of
+## the CDF) at @var{x} of the hypergeometric distribution with parameters
+## @var{t}, @var{m}, and @var{n}.  This is the probability of obtaining @var{x}
+## marked items when randomly drawing a sample of size @var{n} without
+## replacement from a population of total size @var{t} containing @var{m}
+## marked items.
 ##
-## The parameters @var{t}, @var{m}, and @var{n} must positive integers
+## The parameters @var{t}, @var{m}, and @var{n} must be positive integers
 ## with @var{m} and @var{n} not greater than @var{t}.
 ## @end deftypefn

@@ -36,14 +40,75 @@
   endif

   if (!isscalar (t) || !isscalar (m) || !isscalar (n))
-    error ("hygeinv: T, M and N must all be positive integers");
+    [retval, x, t, m, n] = common_size (x, t, m, n);
+    if (retval > 0)
+      error ("hygeinv: X, T, M, and N must be of common size or scalars");
+    endif
+  endif
+
+  if (iscomplex (x) || iscomplex (t) || iscomplex (m) || iscomplex (n))
+    error ("hygeinv: X, T, M, and N must not be complex");
+  endif
+
+  if (isa (x, "single") || isa (t, "single") || isa (m, "single") || isa (n, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  if (t < 0 || m < 0 || n <= 0 || t != round (t) || m != round (m)
-      || n != round (n) || m > t || n > t)
-    inv = NaN (size (x));
+  ok = ((t >= 0) & (m >= 0) & (n > 0) & (m <= t) & (n <= t) &
+        (t == fix (t)) & (m == fix (m)) & (n == fix (n)));
+
+  if (isscalar (t))
+    if (ok)
+      inv = discrete_inv (x, 0 : n, hygepdf (0 : n, t, m, n));
+      inv(x == 0) = 0;  # Hack to return correct value for start of distribution
+    endif
   else
-    inv = discrete_inv (x, 0 : n, hygepdf (0 : n, t, m, n));
+    for i = find (ok(:)')  # Must be row vector arg to for loop
+      v = 0 : n(i);
+      if (x(i) == 0)
+        inv(i) = 0;  # Hack to return correct value for start of distribution
+      else
+        inv(i) = discrete_inv (x(i), v, hygepdf (v, t(i), m(i), n(i)));
+      endif
+    endfor
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(hygeinv (x, 4*ones(1,5), 2*ones(1,5), 2*ones(1,5)), [NaN 0 1 2 NaN]);
+%!assert(hygeinv (x, 4*ones(1,5), 2, 2), [NaN 0 1 2 NaN]);
+%!assert(hygeinv (x, 4, 2*ones(1,5), 2), [NaN 0 1 2 NaN]);
+%!assert(hygeinv (x, 4, 2, 2*ones(1,5)), [NaN 0 1 2 NaN]);
+%!assert(hygeinv (x, 4*[1 -1 NaN 1.1 1], 2, 2), [NaN NaN NaN NaN NaN]);
+%!assert(hygeinv (x, 4, 2*[1 -1 NaN 1.1 1], 2), [NaN NaN NaN NaN NaN]);
+%!assert(hygeinv (x, 4, 5, 2), [NaN NaN NaN NaN NaN]);
+%!assert(hygeinv (x, 4, 2, 2*[1 -1 NaN 1.1 1]), [NaN NaN NaN NaN NaN]);
+%!assert(hygeinv (x, 4, 2, 5), [NaN NaN NaN NaN NaN]);
+%!assert(hygeinv ([x(1:2) NaN x(4:5)], 4, 2, 2), [NaN 0 NaN 2 NaN]);
+
+%% Test class of input preserved
+%!assert(hygeinv ([x, NaN], 4, 2, 2), [NaN 0 1 2 NaN NaN]);
+%!assert(hygeinv (single([x, NaN]), 4, 2, 2), single([NaN 0 1 2 NaN NaN]));
+%!assert(hygeinv ([x, NaN], single(4), 2, 2), single([NaN 0 1 2 NaN NaN]));
+%!assert(hygeinv ([x, NaN], 4, single(2), 2), single([NaN 0 1 2 NaN NaN]));
+%!assert(hygeinv ([x, NaN], 4, 2, single(2)), single([NaN 0 1 2 NaN NaN]));
+
+%% Test input validation
+%!error hygeinv ()
+%!error hygeinv (1)
+%!error hygeinv (1,2)
+%!error hygeinv (1,2,3)
+%!error hygeinv (1,2,3,4,5)
+%!error hygeinv (ones(2), ones(3), 1, 1)
+%!error hygeinv (1, ones(2), ones(3), 1)
+%!error hygeinv (1, 1, ones(2), ones(3))
+%!error hygeinv (i, 2, 2, 2)
+%!error hygeinv (2, i, 2, 2)
+%!error hygeinv (2, 2, i, 2)
+%!error hygeinv (2, 2, 2, i)
+
--- a/scripts/statistics/distributions/hygepdf.m
+++ b/scripts/statistics/distributions/hygepdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1996-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -24,7 +25,8 @@
 ## when randomly drawing a sample of size @var{n} without replacement
 ## from a population of total size @var{t} containing @var{m} marked items.
 ##
-## The arguments must be of common size or scalar.
+## The parameters @var{t}, @var{m}, and @var{n} must be positive integers
+## with @var{m} and @var{n} not greater than @var{t}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -39,34 +41,72 @@
   if (!isscalar (t) || !isscalar (m) || !isscalar (n))
     [retval, x, t, m, n] = common_size (x, t, m, n);
     if (retval > 0)
-      error ("hygepdf: X, T, M, and N must be of common size or scalar");
+      error ("hygepdf: X, T, M, and N must be of common size or scalars");
     endif
   endif

-  pdf = zeros (size (x));
+  if (iscomplex (x) || iscomplex (t) || iscomplex (m) || iscomplex (n))
+    error ("hygepdf: X, T, M, and N must not be complex");
+  endif
+
+  if (isa (x, "single") || isa (t, "single") || isa (m, "single") || isa (n, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
+  endif

-  ## everything in i1 gives NaN
-  i1 = ((t < 0) | (m < 0) | (n <= 0) | (t != round (t)) |
-        (m != round (m)) | (n != round (n)) | (m > t) | (n > t));
-  ## everything in i2 gives 0 unless in i1
-  i2 = ((x != round (x)) | (x < 0) | (x > m) | (n < x) | (n-x > t-m));
-  k = find (i1);
-  if (any (k))
+  ## everything in nel gives NaN
+  nel = (isnan (x) | (t < 0) | (m < 0) | (n <= 0) | (m > t) | (n > t) |
+        (t != fix (t)) | (m != fix (m)) | (n != fix (n)));
+  ## everything in zel gives 0 unless in nel
+  zel = ((x != fix (x)) | (x < 0) | (x > m) | (n < x) | (n-x > t-m));
+
+  pdf(nel) = NaN;
+
+  k = !nel & !zel;
+  if (any (k(:)))
     if (isscalar (t) && isscalar (m) && isscalar (n))
-      pdf = NaN (size (x));
+      pdf(k) = (bincoeff (m, x(k)) .* bincoeff (t-m, n-x(k))
+                / bincoeff (t, n));
     else
-      pdf (k) = NaN;
-    endif
-  endif
-  k = find (!i1 & !i2);
-  if (any (k))
-    if (isscalar (t) && isscalar (m) && isscalar (n))
-      pdf (k) = (bincoeff (m, x(k)) .* bincoeff (t-m, n-x(k))
-                 / bincoeff (t, n));
-    else
-      pdf (k) = (bincoeff (m(k), x(k)) .* bincoeff (t(k)-m(k), n(k)-x(k))
-                 ./ bincoeff (t(k), n(k)));
+      pdf(k) = (bincoeff (m(k), x(k)) .* bincoeff (t(k)-m(k), n(k)-x(k))
+                ./ bincoeff (t(k), n(k)));
     endif
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 2 3];
+%! y = [0 1/6 4/6 1/6 0];
+%!assert(hygepdf (x, 4*ones(1,5), 2, 2), y);
+%!assert(hygepdf (x, 4, 2*ones(1,5), 2), y);
+%!assert(hygepdf (x, 4, 2, 2*ones(1,5)), y);
+%!assert(hygepdf (x, 4*[1 -1 NaN 1.1 1], 2, 2), [0 NaN NaN NaN 0]);
+%!assert(hygepdf (x, 4, 2*[1 -1 NaN 1.1 1], 2), [0 NaN NaN NaN 0]);
+%!assert(hygepdf (x, 4, 5, 2), [NaN NaN NaN NaN NaN]);
+%!assert(hygepdf (x, 4, 2, 2*[1 -1 NaN 1.1 1]), [0 NaN NaN NaN 0]);
+%!assert(hygepdf (x, 4, 2, 5), [NaN NaN NaN NaN NaN]);
+%!assert(hygepdf ([x, NaN], 4, 2, 2), [y, NaN], eps);
+
+%% Test class of input preserved
+%!assert(hygepdf (single([x, NaN]), 4, 2, 2), single([y, NaN]));
+%!assert(hygepdf ([x, NaN], single(4), 2, 2), single([y, NaN]));
+%!assert(hygepdf ([x, NaN], 4, single(2), 2), single([y, NaN]));
+%!assert(hygepdf ([x, NaN], 4, 2, single(2)), single([y, NaN]));
+
+%% Test input validation
+%!error hygepdf ()
+%!error hygepdf (1)
+%!error hygepdf (1,2)
+%!error hygepdf (1,2,3)
+%!error hygepdf (1,2,3,4,5)
+%!error hygepdf (1, ones(3),ones(2),ones(2))
+%!error hygepdf (1, ones(2),ones(3),ones(2))
+%!error hygepdf (1, ones(2),ones(2),ones(3))
+%!error hygepdf (i, 2, 2, 2)
+%!error hygepdf (2, i, 2, 2)
+%!error hygepdf (2, 2, i, 2)
+%!error hygepdf (2, 2, 2, i)
+
--- a/scripts/statistics/distributions/hygernd.m
+++ b/scripts/statistics/distributions/hygernd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1997-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,81 +18,131 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} hygernd (@var{t}, @var{m}, @var{n}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} hygernd (@var{t}, @var{m}, @var{n}, @var{sz})
-## @deftypefnx {Function File} {} hygernd (@var{t}, @var{m}, @var{n})
-## Return an @var{r} by @var{c} matrix of random samples from the
-## hypergeometric distribution with parameters @var{t}, @var{m},
-## and @var{n}.
+## @deftypefn  {Function File} {} hygernd (@var{t}, @var{m}, @var{n})
+## @deftypefnx {Function File} {} hygernd (@var{t}, @var{m}, @var{n}, @var{r})
+## @deftypefnx {Function File} {} hygernd (@var{t}, @var{m}, @var{n}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} hygernd (@var{t}, @var{m}, @var{n}, [@var{sz}])
+## Return a matrix of random samples from the hypergeometric distribution
+## with parameters @var{t}, @var{m}, and @var{n}.
 ##
-## The parameters @var{t}, @var{m}, and @var{n} must positive integers
+## The parameters @var{t}, @var{m}, and @var{n} must be positive integers
 ## with @var{m} and @var{n} not greater than @var{t}.
 ##
-## The parameter @var{sz} must be scalar or a vector of matrix
-## dimensions.  If @var{sz} is scalar, then a @var{sz} by @var{sz}
-## matrix of random samples is generated.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{t}, @var{m}, and @var{n}.
 ## @end deftypefn

-function rnd = hygernd (t, m, n, r, c)
+function rnd = hygernd (t, m, n, varargin)

-  if (nargin == 5)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("hygernd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("hygernd: C must be a positive integer");
-    endif
-    sz = [r, c];
-  elseif (nargin == 4)
-    if (isvector (r) && all (r > 0) && all (r == round (r)))
-      if (isscalar (r))
-        sz = [r, r];
-      else
-        sz = r(:)';
-      endif
-    else
-      error ("hygernd: R must be a vector of positive integers");
-    endif
-  elseif (nargin != 3)
+  if (nargin < 3)
     print_usage ();
   endif

   if (! isscalar (t) || ! isscalar (m) || ! isscalar (n))
     [retval, t, m, n] = common_size (t, m, n);
     if (retval > 0)
-      error ("hygernd: T, M and N must be of common size or scalar");
+      error ("hygernd: T, M, and N must be of common size or scalars");
+    endif
+  endif
+
+  if (iscomplex (t) || iscomplex (m) || iscomplex (n))
+    error ("hygernd: T, M, and N must not be complex");
+  endif
+
+  if (nargin == 3)
+    sz = size (t);
+  elseif (nargin == 4)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("hygernd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 4)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("hygernd: dimensions must be non-negative integers");
     endif
-    if (nargin > 3)
-      if (any (sz != size (t)))
-        error ("hygernd: T, M and N must have the same size as implied by R and C or must be scalar");
+    sz = [varargin{:}];
+  endif
+
+  if (!isscalar (t) && !isequal (size (t), sz))
+    error ("hygernd: T, M, and N must be scalar or of size SZ");
+  endif
+
+  if (isa (t, "single") || isa (m, "single") || isa (n, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif
+
+  ok = ((t >= 0) & (m >= 0) & (n > 0) & (m <= t) & (n <= t) &
+        (t == fix (t)) & (m == fix (m)) & (n == fix (n)));
+
+  if (isscalar (t))
+    if (ok)
+      v = 0:n;
+      p = hygepdf (v, t, m, n);
+      rnd = v(lookup (cumsum (p(1:end-1)) / sum (p), rand (sz)) + 1);
+      rnd = reshape (rnd, sz);
+      if (strcmp (cls, "single"))
+        rnd = single (rnd);
       endif
     else
-      sz = size (t);
+      rnd = NaN (sz, cls);
     endif
-  elseif (nargin == 3)
-    sz = 1;
-  endif
-
-  ## NaN elements
-  ne = (! (t >= 0) | ! (m >= 0) | ! (n > 0) | ! (t == round (t)) | ! (m == round (m)) | ! (n == round (n)) | ! (m <= t) | ! (n <= t));
-
-  if (! isscalar (t))
-    rnd = zeros (sz);
-    rnd(ne) = NaN;
+  else
+    rnd = NaN (sz, cls);
     rn = rand (sz);
-    for i = find (! ne)
+    for i = find (ok(:)')  # Must be row vector arg to for loop
       v = 0 : n(i);
       p = hygepdf (v, t(i), m(i), n(i));
       rnd(i) = v(lookup (cumsum (p(1 : end-1)) / sum (p), rn(i)) + 1);
     endfor
-  else
-    if (ne)
-      rnd = NaN (sz);
-    else
-      v = 0:n;
-      p = hygepdf (v, t, m, n);
-      rnd = v(lookup (cumsum (p(1:end-1)) / sum (p), rand (sz)) + 1);
-    endif
   endif

 endfunction
+
+
+%!assert(size (hygernd (4,2,2)), [1, 1]);
+%!assert(size (hygernd (4*ones(2,1), 2,2)), [2, 1]);
+%!assert(size (hygernd (4*ones(2,2), 2,2)), [2, 2]);
+%!assert(size (hygernd (4, 2*ones(2,1), 2)), [2, 1]);
+%!assert(size (hygernd (4, 2*ones(2,2), 2)), [2, 2]);
+%!assert(size (hygernd (4, 2, 2*ones(2,1))), [2, 1]);
+%!assert(size (hygernd (4, 2, 2*ones(2,2))), [2, 2]);
+%!assert(size (hygernd (4, 2, 2, 3)), [3, 3]);
+%!assert(size (hygernd (4, 2, 2, [4 1])), [4, 1]);
+%!assert(size (hygernd (4, 2, 2, 4, 1)), [4, 1]);
+
+%!assert(class (hygernd (4,2,2)), "double");
+%!assert(class (hygernd (single(4),2,2)), "single");
+%!assert(class (hygernd (single([4 4]),2,2)), "single");
+%!assert(class (hygernd (4,single(2),2)), "single");
+%!assert(class (hygernd (4,single([2 2]),2)), "single");
+%!assert(class (hygernd (4,2,single(2))), "single");
+%!assert(class (hygernd (4,2,single([2 2]))), "single");
+
+%% Test input validation
+%!error hygernd ()
+%!error hygernd (1)
+%!error hygernd (1,2)
+%!error hygernd (ones(3),ones(2),ones(2), 2)
+%!error hygernd (ones(2),ones(3),ones(2), 2)
+%!error hygernd (ones(2),ones(2),ones(3), 2)
+%!error hygernd (i, 2, 2)
+%!error hygernd (2, i, 2)
+%!error hygernd (2, 2, i)
+%!error hygernd (4,2,2, -1)
+%!error hygernd (4,2,2, ones(2))
+%!error hygernd (4,2,2, [2 -1 2])
+%!error hygernd (4*ones(2),2,2, 3)
+%!error hygernd (4*ones(2),2,2, [3, 2])
+%!error hygernd (4*ones(2),2,2, 3, 2)
+
--- a/scripts/statistics/distributions/kolmogorov_smirnov_cdf.m
+++ b/scripts/statistics/distributions/kolmogorov_smirnov_cdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,16 +19,17 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} kolmogorov_smirnov_cdf (@var{x}, @var{tol})
-## Return the CDF at @var{x} of the Kolmogorov-Smirnov distribution,
+## Return the cumulative distribution function (CDF) at @var{x} of the
+## Kolmogorov-Smirnov distribution,
 ## @tex
-## $$ Q(x) = \sum_{k=-\infty}^\infty (-1)^k \exp(-2 k^2 x^2) $$
+## $$ Q(x) = \sum_{k=-\infty}^\infty (-1)^k \exp (-2 k^2 x^2) $$
 ## @end tex
 ## @ifnottex
 ##
 ## @example
 ## @group
 ##          Inf
-## Q(x) =   SUM    (-1)^k exp(-2 k^2 x^2)
+## Q(x) =   SUM    (-1)^k exp (-2 k^2 x^2)
 ##        k = -Inf
 ## @end group
 ## @end example
@@ -61,8 +63,7 @@
     endif
   endif

-  n = numel (x);
-  if (n == 0)
+  if (numel (x) == 0)
     error ("kolmogorov_smirnov_cdf: X must not be empty");
   endif

@@ -70,10 +71,10 @@

   ind = find (x > 0);
   if (length (ind) > 0)
-    if (size(ind,2) < size(ind,1))
+    if (columns (ind) < rows (ind))
       y = x(ind.');
     else
-      y   = x(ind);
+      y = x(ind);
     endif
     K   = ceil (sqrt (- log (tol) / 2) / min (y));
     k   = (1:K)';
@@ -84,3 +85,11 @@
   endif

 endfunction
+
+
+%% Test input validation
+%!error kolmogorov_smirnov_cdf ()
+%!error kolmogorov_smirnov_cdf (1,2,3)
+%!error kolmogorov_smirnov_cdf (1, ones(2))
+%!error kolmogorov_smirnov_cdf ([], 1)
+
--- a/scripts/statistics/distributions/laplace_cdf.m
+++ b/scripts/statistics/distributions/laplace_cdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -31,21 +32,25 @@
     print_usage ();
   endif

-  cdf = zeros (size (x));
-
-  k = find (isnan (x));
-  if (any (k))
-    cdf(k) = NaN;
+  if (iscomplex (x))
+    error ("laplace_cdf: X must not be complex");
   endif

-  k = find (x == Inf);
-  if (any (k))
-    cdf(k) = 1;
-  endif
-
-  k = find ((x > -Inf) & (x < Inf));
-  if (any (k))
-    cdf(k) = (1 + sign (x(k)) .* (1 - exp (- abs (x(k))))) / 2;
-  endif
+  cdf = (1 + sign (x) .* (1 - exp (- abs (x)))) / 2;

 endfunction
+
+
+%!shared x,y
+%! x = [-Inf -log(2) 0 log(2) Inf];
+%! y = [0, 1/4, 1/2, 3/4, 1];
+%!assert(laplace_cdf ([x, NaN]), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(laplace_cdf (single([x, NaN])), single([y, NaN]));
+
+%% Test input validation
+%!error laplace_cdf ()
+%!error laplace_cdf (1,2)
+%!error laplace_cdf (i)
+
--- a/scripts/statistics/distributions/laplace_inv.m
+++ b/scripts/statistics/distributions/laplace_inv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -31,22 +32,33 @@
     print_usage ();
   endif

-  inv = -Inf (size (x));
+  if (iscomplex (x))
+    error ("laplace_inv: X must not be complex");
+  endif

-  k = find (isnan (x) | (x < 0) | (x > 1));
-  if (any (k))
-    inv(k) = NaN;
+  if (isa (x, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  k = find (x == 1);
-  if (any (k))
-    inv(k) = Inf;
-  endif
-
-  k = find ((x > 0) & (x < 1));
-  if (any (k))
-    inv(k) = ((x(k) < 1/2) .* log (2 * x(k))
-              - (x(k) > 1/2) .* log (2 * (1 - x(k))));
-  endif
+  k = (x >= 0) & (x <= 1);
+  inv(k) = ((x(k) < 1/2) .* log (2 * x(k))
+            - (x(k) > 1/2) .* log (2 * (1 - x(k))));

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(laplace_inv (x), [NaN -Inf 0 Inf NaN]);
+
+%% Test class of input preserved
+%!assert(laplace_inv ([x, NaN]), [NaN -Inf 0 Inf NaN NaN]);
+%!assert(laplace_inv (single([x, NaN])), single([NaN -Inf 0 Inf NaN NaN]));
+
+%% Test input validation
+%!error laplace_inv ()
+%!error laplace_inv (1,2)
+%!error laplace_inv (i)
+
--- a/scripts/statistics/distributions/laplace_pdf.m
+++ b/scripts/statistics/distributions/laplace_pdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -30,17 +31,26 @@
   if (nargin != 1)
     print_usage ();
   endif
-
-  pdf = zeros (size (x));
-
-  k = find (isnan (x));
-  if (any (k))
-    pdf(k) = NaN;
+
+  if (iscomplex (x))
+    error ("laplace_pdf: X must not be complex");
   endif

-  k = find ((x > -Inf) & (x < Inf));
-  if (any (k))
-    pdf(k) = exp (- abs (x(k))) / 2;
-  endif
+  pdf = exp (- abs (x)) / 2;

 endfunction
+
+
+%!shared x,y
+%! x = [-Inf -log(2) 0 log(2) Inf];
+%! y = [0, 1/4, 1/2, 1/4, 0];
+%!assert(laplace_pdf ([x, NaN]), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(laplace_pdf (single([x, NaN])), single([y, NaN]));
+
+%% Test input validation
+%!error laplace_pdf ()
+%!error laplace_pdf (1,2)
+%!error laplace_pdf (i)
+
--- a/scripts/statistics/distributions/laplace_rnd.m
+++ b/scripts/statistics/distributions/laplace_rnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,40 +18,57 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} laplace_rnd (@var{r}, @var{c})
-## @deftypefnx {Function File} {} laplace_rnd (@var{sz});
-## Return an @var{r} by @var{c} matrix of random numbers from the
-## Laplace distribution.  Or if @var{sz} is a vector, create a matrix of
-## @var{sz}.
+## @deftypefn  {Function File} {} laplace_rnd (@var{r})
+## @deftypefnx {Function File} {} laplace_rnd (@var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} laplace_rnd ([@var{sz}])
+## Return a matrix of random samples from the Laplace distribution.
+##
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the Laplace distribution

-function rnd = laplace_rnd (r, c)
+function rnd = laplace_rnd (varargin)

-  if (nargin == 2)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("laplace_rnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("laplace_rnd: C must be a positive integer");
-    endif
-    sz = [r, c];
-  elseif (nargin == 1)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("laplace_rnd: R must be a positive integer or vector");
-    endif
-  else
+  if (nargin < 1)
     print_usage ();
   endif

+  if (nargin == 1)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1}(:)';
+    else
+      error ("laplace_rnd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 1)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("laplace_rnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif
+
   tmp = rand (sz);
-  rnd = ((tmp < 1/2) .* log (2 * tmp)
-         - (tmp > 1/2) .* log (2 * (1 - tmp)));
+  rnd = (tmp < 1/2) .* log (2 * tmp) - (tmp > 1/2) .* log (2 * (1 - tmp));

 endfunction
+
+
+%!assert(size (laplace_rnd (3)), [3, 3]);
+%!assert(size (laplace_rnd ([4 1])), [4, 1]);
+%!assert(size (laplace_rnd (4,1)), [4, 1]);
+
+%% Test input validation
+%!error laplace_rnd ()
+%!error laplace_rnd (-1)
+%!error laplace_rnd (ones(2))
+%!error laplace_rnd ([2 -1 2])
+%!error laplace_rnd (1, ones(2))
+%!error laplace_rnd (1, -1)
+
--- a/scripts/statistics/distributions/logistic_cdf.m
+++ b/scripts/statistics/distributions/logistic_cdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,8 +19,8 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} logistic_cdf (@var{x})
-## For each component of @var{x}, compute the CDF at @var{x} of the
-## logistic distribution.
+## For each element of @var{x}, compute the cumulative distribution function
+## (CDF) at @var{x} of the logistic distribution.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -31,6 +32,25 @@
     print_usage ();
   endif

-  cdf = 1 ./ (1 + exp (- x));
+  if (iscomplex (x))
+    error ("logistic_cdf: X must not be complex");
+  endif
+
+  cdf = 1 ./ (1 + exp (-x));

 endfunction
+
+
+%!shared x,y
+%! x = [-Inf -log(3) 0 log(3) Inf];
+%! y = [0, 1/4, 1/2, 3/4, 1];
+%!assert(logistic_cdf ([x, NaN]), [y, NaN], eps);
+
+%% Test class of input preserved
+%!assert(logistic_cdf (single([x, NaN])), single([y, NaN]), eps ("single"));
+
+%% Test input validation
+%!error logistic_cdf ()
+%!error logistic_cdf (1,2)
+%!error logistic_cdf (i)
+
--- a/scripts/statistics/distributions/logistic_inv.m
+++ b/scripts/statistics/distributions/logistic_inv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,7 +19,7 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} logistic_inv (@var{x})
-## For each component of @var{x}, compute the quantile (the inverse of
+## For each element of @var{x}, compute the quantile (the inverse of
 ## the CDF) at @var{x} of the logistic distribution.
 ## @end deftypefn

@@ -31,30 +32,38 @@
     print_usage ();
   endif

-  if (isa (x, 'single'))
-    inv = zeros (size (x), 'single');
-  else
-    inv = zeros (size (x));
+  if (iscomplex (x))
+    error ("logistic_inv: X must not be complex");
   endif

-  k = find ((x < 0) | (x > 1) | isnan (x));
-  if (any (k))
-    inv(k) = NaN;
+  if (isa (x, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  k = find (x == 0);
-  if (any (k))
-    inv(k) = -Inf;
-  endif
+  k = (x == 0);
+  inv(k) = -Inf;

-  k = find (x == 1);
-  if (any (k))
-    inv(k) = Inf;
-  endif
+  k = (x == 1);
+  inv(k) = Inf;

-  k = find ((x > 0) & (x < 1));
-  if (any (k))
-    inv (k) = - log (1 ./ x(k) - 1);
-  endif
+  k = (x > 0) & (x < 1);
+  inv(k) = - log (1 ./ x(k) - 1);

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(logistic_inv (x), [NaN -Inf 0 Inf NaN]);
+
+%% Test class of input preserved
+%!assert(logistic_inv ([x, NaN]), [NaN -Inf 0 Inf NaN NaN]);
+%!assert(logistic_inv (single([x, NaN])), single([NaN -Inf 0 Inf NaN NaN]));
+
+%% Test input validation
+%!error logistic_inv ()
+%!error logistic_inv (1,2)
+%!error logistic_inv (i)
+
--- a/scripts/statistics/distributions/logistic_pdf.m
+++ b/scripts/statistics/distributions/logistic_pdf.m
@@ -18,7 +18,7 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} logistic_pdf (@var{x})
-## For each component of @var{x}, compute the PDF at @var{x} of the
+## For each element of @var{x}, compute the PDF at @var{x} of the
 ## logistic distribution.
 ## @end deftypefn

@@ -31,7 +31,26 @@
     print_usage ();
   endif

+  if (iscomplex (x))
+    error ("logistic_pdf: X must not be complex");
+  endif
+
   cdf = logistic_cdf (x);
   pdf = cdf .* (1 - cdf);

 endfunction
+
+
+%!shared x,y
+%! x = [-Inf -log(4) 0 log(4) Inf];
+%! y = [0, 0.16, 1/4, 0.16, 0];
+%!assert(logistic_pdf ([x, NaN]), [y, NaN], eps);
+
+%% Test class of input preserved
+%!assert(logistic_pdf (single([x, NaN])), single([y, NaN]), eps ("single"));
+
+%% Test input validation
+%!error logistic_pdf ()
+%!error logistic_pdf (1,2)
+%!error logistic_pdf (i)
+
--- a/scripts/statistics/distributions/logistic_rnd.m
+++ b/scripts/statistics/distributions/logistic_rnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,39 +18,56 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} logistic_rnd (@var{r}, @var{c})
-## @deftypefnx {Function File} {} logistic_rnd (@var{sz})
-## Return an @var{r} by @var{c} matrix of random numbers from the
-## logistic distribution.  Or if @var{sz} is a vector, create a matrix of
-## @var{sz}.
+## @deftypefn  {Function File} {} logistic_rnd (@var{r})
+## @deftypefnx {Function File} {} logistic_rnd (@var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} logistic_rnd ([@var{sz}])
+## Return a matrix of random samples from the logistic distribution.
+##
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the logistic distribution

-function rnd = logistic_rnd (r, c)
+function rnd = logistic_rnd (varargin)

+  if (nargin < 1)
+    print_usage ();
+  endif

-  if (nargin == 2)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("logistic_rnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("logistic_rnd: C must be a positive integer");
+  if (nargin == 1)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("logistic_rnd: dimension vector must be row vector of non-negative integers");
     endif
-    sz = [r, c];
-  elseif (nargin == 1)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("logistic_rnd: R must be a positive integer or vector");
+  elseif (nargin > 1)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("logistic_rnd: dimensions must be non-negative integers");
     endif
-  else
-    print_usage ();
+    sz = [varargin{:}];
   endif

   rnd = - log (1 ./ rand (sz) - 1);

 endfunction
+
+
+%!assert(size (logistic_rnd (3)), [3, 3]);
+%!assert(size (logistic_rnd ([4 1])), [4, 1]);
+%!assert(size (logistic_rnd (4,1)), [4, 1]);
+
+%% Test input validation
+%!error logistic_rnd ()
+%!error logistic_rnd (-1)
+%!error logistic_rnd (ones(2))
+%!error logistic_rnd ([2 -1 2])
+%!error logistic_rnd (1, ones(2))
+%!error logistic_rnd (1, -1)
+
--- a/scripts/statistics/distributions/logncdf.m
+++ b/scripts/statistics/distributions/logncdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,7 +18,8 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} logncdf (@var{x}, @var{mu}, @var{sigma})
+## @deftypefn  {Function File} {} logncdf (@var{x})
+## @deftypefnx {Function File} {} logncdf (@var{x}, @var{mu}, @var{sigma})
 ## For each element of @var{x}, compute the cumulative distribution
 ## function (CDF) at @var{x} of the lognormal distribution with
 ## parameters @var{mu} and @var{sigma}.  If a random variable follows this
@@ -30,48 +32,69 @@
 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: CDF of the log normal distribution

-function cdf = logncdf (x, mu, sigma)
+function cdf = logncdf (x, mu = 0, sigma = 1)

-  if (! ((nargin == 1) || (nargin == 3)))
+  if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    mu = 0;
-    sigma = 1;
-  endif
-
-  ## The following "straightforward" implementation unfortunately does
-  ## not work (because exp (Inf) -> NaN etc):
-  ## cdf = normal_cdf (log (x), log (mu), sigma);
-  ## Hence ...
-
   if (!isscalar (mu) || !isscalar (sigma))
     [retval, x, mu, sigma] = common_size (x, mu, sigma);
     if (retval > 0)
-      error ("logncdf: X, MU and SIGMA must be of common size or scalars");
+      error ("logncdf: X, MU, and SIGMA must be of common size or scalars");
     endif
   endif

-  cdf = zeros (size (x));
+  if (iscomplex (x) || iscomplex (mu) || iscomplex (sigma))
+    error ("logncdf: X, MU, and SIGMA must not be complex");
+  endif

-  k = find (isnan (x) | !(sigma > 0) | !(sigma < Inf));
-  if (any (k))
-    cdf(k) = NaN;
+  if (isa (x, "single") || isa (mu, "single") || isa (sigma, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x == Inf) & (sigma > 0) & (sigma < Inf));
-  if (any (k))
-    cdf(k) = 1;
-  endif
+  k = isnan (x) | !(sigma > 0) | !(sigma < Inf);
+  cdf(k) = NaN;
+
+  k = (x == Inf) & (sigma > 0) & (sigma < Inf);
+  cdf(k) = 1;

-  k = find ((x > 0) & (x < Inf) & (sigma > 0) & (sigma < Inf));
-  if (any (k))
-    if (isscalar (mu) && isscalar (sigma))
-      cdf(k) = stdnormal_cdf ((log (x(k)) - mu) / sigma);
-    else
-      cdf(k) = stdnormal_cdf ((log (x(k)) - mu(k)) ./ sigma(k));
-    endif
+  k = (x > 0) & (x < Inf) & (sigma > 0) & (sigma < Inf);
+  if (isscalar (mu) && isscalar (sigma))
+    cdf(k) = stdnormal_cdf ((log (x(k)) - mu) / sigma);
+  else
+    cdf(k) = stdnormal_cdf ((log (x(k)) - mu(k)) ./ sigma(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 e Inf];
+%! y = [0, 0, 0.5, 1/2+1/2*erf(1/2), 1];
+%!assert(logncdf (x, zeros(1,5), sqrt(2)*ones(1,5)), y);
+%!assert(logncdf (x, 0, sqrt(2)*ones(1,5)), y);
+%!assert(logncdf (x, zeros(1,5), sqrt(2)), y);
+%!assert(logncdf (x, [0 1 NaN 0 1], sqrt(2)), [0 0 NaN y(4:5)]);
+%!assert(logncdf (x, 0, sqrt(2)*[0 NaN Inf 1 1]), [NaN NaN NaN y(4:5)]);
+%!assert(logncdf ([x(1:3) NaN x(5)], 0, sqrt(2)), [y(1:3) NaN y(5)]);
+
+%% Test class of input preserved
+%!assert(logncdf ([x, NaN], 0, sqrt(2)), [y, NaN]);
+%!assert(logncdf (single([x, NaN]), 0, sqrt(2)), single([y, NaN]), eps("single"));
+%!assert(logncdf ([x, NaN], single(0), sqrt(2)), single([y, NaN]), eps("single"));
+%!assert(logncdf ([x, NaN], 0, single(sqrt(2))), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error logncdf ()
+%!error logncdf (1,2)
+%!error logncdf (1,2,3,4)
+%!error logncdf (ones(3),ones(2),ones(2))
+%!error logncdf (ones(2),ones(3),ones(2))
+%!error logncdf (ones(2),ones(2),ones(3))
+%!error logncdf (i, 2, 2)
+%!error logncdf (2, i, 2)
+%!error logncdf (2, 2, i)
+
--- a/scripts/statistics/distributions/logninv.m
+++ b/scripts/statistics/distributions/logninv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,7 +18,8 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} logninv (@var{x}, @var{mu}, @var{sigma})
+## @deftypefn  {Function File} {} logninv (@var{x})
+## @deftypefnx {Function File} {} logninv (@var{x}, @var{mu}, @var{sigma})
 ## For each element of @var{x}, compute the quantile (the inverse of the
 ## CDF) at @var{x} of the lognormal distribution with parameters @var{mu}
 ## and @var{sigma}.  If a random variable follows this distribution, its
@@ -30,48 +32,68 @@
 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Quantile function of the log normal distribution

-function inv = logninv (x, mu, sigma)
+function inv = logninv (x, mu = 0, sigma = 1)

-  if (! ((nargin == 1) || (nargin == 3)))
+  if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    mu = 0;
-    sigma = 1;
-  endif
-
-  ## The following "straightforward" implementation unfortunately does
-  ## not work (because exp (Inf) -> NaN):
-  ## inv = exp (norminv (x, mu, sigma));
-  ## Hence ...
-
   if (!isscalar (mu) || !isscalar (sigma))
     [retval, x, mu, sigma] = common_size (x, mu, sigma);
     if (retval > 0)
-      error ("logninv: X, MU and SIGMA must be of common size or scalars");
+      error ("logninv: X, MU, and SIGMA must be of common size or scalars");
     endif
   endif

-  inv = zeros (size (x));
+  if (iscomplex (x) || iscomplex (mu) || iscomplex (sigma))
+    error ("logninv: X, MU, and SIGMA must not be complex");
+  endif

-  k = find (!(x >= 0) | !(x <= 1) | !(sigma > 0) | !(sigma < Inf));
-  if (any (k))
-    inv(k) = NaN;
+  if (isa (x, "single") || isa (mu, "single") || isa (sigma, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  k = find ((x == 1) & (sigma > 0) & (sigma < Inf));
-  if (any (k))
-    inv(k) = Inf;
-  endif
+  k = !(x >= 0) | !(x <= 1) | !(sigma > 0) | !(sigma < Inf);
+  inv(k) = NaN;
+
+  k = (x == 1) & (sigma > 0) & (sigma < Inf);
+  inv(k) = Inf;

-  k = find ((x > 0) & (x < 1) & (sigma > 0) & (sigma < Inf));
-  if (any (k))
-    if (isscalar (mu) && isscalar (sigma))
-      inv(k) = exp (mu) .* exp (sigma .* stdnormal_inv (x(k)));
-    else
-      inv(k) = exp (mu(k)) .* exp (sigma(k) .* stdnormal_inv (x(k)));
-    endif
+  k = (x >= 0) & (x < 1) & (sigma > 0) & (sigma < Inf);
+  if (isscalar (mu) && isscalar (sigma))
+    inv(k) = exp (mu) .* exp (sigma .* stdnormal_inv (x(k)));
+  else
+    inv(k) = exp (mu(k)) .* exp (sigma(k) .* stdnormal_inv (x(k)));
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(logninv (x, ones(1,5), ones(1,5)), [NaN 0 e Inf NaN]);
+%!assert(logninv (x, 1, ones(1,5)), [NaN 0 e Inf NaN]);
+%!assert(logninv (x, ones(1,5), 1), [NaN 0 e Inf NaN]);
+%!assert(logninv (x, [1 1 NaN 0 1], 1), [NaN 0 NaN Inf NaN]);
+%!assert(logninv (x, 1, [1 0 NaN Inf 1]), [NaN NaN NaN NaN NaN]);
+%!assert(logninv ([x(1:2) NaN x(4:5)], 1, 2), [NaN 0 NaN Inf NaN]);
+
+%% Test class of input preserved
+%!assert(logninv ([x, NaN], 1, 1), [NaN 0 e Inf NaN NaN]);
+%!assert(logninv (single([x, NaN]), 1, 1), single([NaN 0 e Inf NaN NaN]));
+%!assert(logninv ([x, NaN], single(1), 1), single([NaN 0 e Inf NaN NaN]));
+%!assert(logninv ([x, NaN], 1, single(1)), single([NaN 0 e Inf NaN NaN]));
+
+%% Test input validation
+%!error logninv ()
+%!error logninv (1,2)
+%!error logninv (1,2,3,4)
+%!error logninv (ones(3),ones(2),ones(2))
+%!error logninv (ones(2),ones(3),ones(2))
+%!error logninv (ones(2),ones(2),ones(3))
+%!error logninv (i, 2, 2)
+%!error logninv (2, i, 2)
+%!error logninv (2, 2, i)
+
--- a/scripts/statistics/distributions/lognpdf.m
+++ b/scripts/statistics/distributions/lognpdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,7 +18,8 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} lognpdf (@var{x}, @var{mu}, @var{sigma})
+## @deftypefn  {Function File} {} lognpdf (@var{x})
+## @deftypefnx {Function File} {} lognpdf (@var{x}, @var{mu}, @var{sigma})
 ## For each element of @var{x}, compute the probability density function
 ## (PDF) at @var{x} of the lognormal distribution with parameters
 ## @var{mu} and @var{sigma}.  If a random variable follows this distribution,
@@ -30,43 +32,65 @@
 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: PDF of the log normal distribution

-function pdf = lognpdf (x, mu, sigma)
+function pdf = lognpdf (x, mu = 0, sigma = 1)

-  if (! ((nargin == 1) || (nargin == 3)))
+  if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    mu = 0;
-    sigma = 1;
-  endif
-
-  ## The following "straightforward" implementation unfortunately does
-  ## not work for the special cases (Inf, ...)
-  ## pdf = (x > 0) ./ x .* normpdf (log (x), mu, sigma);
-  ## Hence ...
-
   if (!isscalar (mu) || !isscalar (sigma))
     [retval, x, mu, sigma] = common_size (x, mu, sigma);
     if (retval > 0)
-      error ("lognpdf: X, MU and SIGMA must be of common size or scalars");
+      error ("lognpdf: X, MU, and SIGMA must be of common size or scalars");
     endif
   endif

-  pdf = zeros (size (x));
-
-  k = find (isnan (x) | !(sigma > 0) | !(sigma < Inf));
-  if (any (k))
-    pdf(k) = NaN;
+  if (iscomplex (x) || iscomplex (mu) || iscomplex (sigma))
+    error ("lognpdf: X, MU, and SIGMA must not be complex");
   endif

-  k = find ((x > 0) & (x < Inf) & (sigma > 0) & (sigma < Inf));
-  if (any (k))
-    if (isscalar (mu) && isscalar (sigma))
-      pdf(k) = normpdf (log (x(k)), mu, sigma) ./ x(k);
-    else
-      pdf(k) = normpdf (log (x(k)), mu(k), sigma(k)) ./ x(k);
-    endif
+  if (isa (x, "single") || isa (mu, "single") || isa (sigma, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
+  endif
+
+  k = isnan (x) | !(sigma > 0) | !(sigma < Inf);
+  pdf(k) = NaN;
+
+  k = (x > 0) & (x < Inf) & (sigma > 0) & (sigma < Inf);
+  if (isscalar (mu) && isscalar (sigma))
+    pdf(k) = normpdf (log (x(k)), mu, sigma) ./ x(k);
+  else
+    pdf(k) = normpdf (log (x(k)), mu(k), sigma(k)) ./ x(k);
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 e Inf];
+%! y = [0, 0, 1/(e*sqrt(2*pi)) * exp(-1/2), 0];
+%!assert(lognpdf (x, zeros(1,4), ones(1,4)), y, eps);
+%!assert(lognpdf (x, 0, ones(1,4)), y, eps);
+%!assert(lognpdf (x, zeros(1,4), 1), y, eps);
+%!assert(lognpdf (x, [0 1 NaN 0], 1), [0 0 NaN y(4)], eps);
+%!assert(lognpdf (x, 0, [0 NaN Inf 1]), [NaN NaN NaN y(4)], eps);
+%!assert(lognpdf ([x, NaN], 0, 1), [y, NaN], eps);
+
+%% Test class of input preserved
+%!assert(lognpdf (single([x, NaN]), 0, 1), single([y, NaN]), eps("single"));
+%!assert(lognpdf ([x, NaN], single(0), 1), single([y, NaN]), eps("single"));
+%!assert(lognpdf ([x, NaN], 0, single(1)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error lognpdf ()
+%!error lognpdf (1,2)
+%!error lognpdf (1,2,3,4)
+%!error lognpdf (ones(3),ones(2),ones(2))
+%!error lognpdf (ones(2),ones(3),ones(2))
+%!error lognpdf (ones(2),ones(2),ones(3))
+%!error lognpdf (i, 2, 2)
+%!error lognpdf (2, i, 2)
+%!error lognpdf (2, 2, i)
+
--- a/scripts/statistics/distributions/lognrnd.m
+++ b/scripts/statistics/distributions/lognrnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,76 +18,115 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} lognrnd (@var{mu}, @var{sigma}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} lognrnd (@var{mu}, @var{sigma}, @var{sz})
-## Return an @var{r} by @var{c} matrix of random samples from the
-## lognormal distribution with parameters @var{mu} and @var{sigma}.  Both
-## @var{mu} and @var{sigma} must be scalar or of size @var{r} by @var{c}.
-## Or if @var{sz} is a vector, create a matrix of size @var{sz}.
+## @deftypefn  {Function File} {} lognrnd (@var{mu}, @var{sigma})
+## @deftypefnx {Function File} {} lognrnd (@var{mu}, @var{sigma}, @var{r})
+## @deftypefnx {Function File} {} lognrnd (@var{mu}, @var{sigma}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} lognrnd (@var{mu}, @var{sigma}, [@var{sz}])
+## Return a matrix of random samples from the lognormal distribution with
+## parameters @var{mu} and @var{sigma}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{mu} and @var{sigma}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{mu} and @var{sigma}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the log normal distribution

-function rnd = lognrnd (mu, sigma, r, c)
+function rnd = lognrnd (mu, sigma, varargin)

-  if (nargin > 1)
-    if (!isscalar(mu) || !isscalar(sigma))
-      [retval, mu, sigma] = common_size (mu, sigma);
-      if (retval > 0)
-        error ("lognrnd: MU and SIGMA must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (mu) || !isscalar (sigma))
+    [retval, mu, sigma] = common_size (mu, sigma);
+    if (retval > 0)
+      error ("lognrnd: MU and SIGMA must be of common size or scalars");
     endif
   endif

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("lognrnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("lognrnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+  if (iscomplex (mu) || iscomplex (sigma))
+    error ("lognrnd: MU and SIGMA must not be complex");
+  endif

-    if (any (size (mu) != 1)
-        && ((length (size (mu)) != length (sz)) || any (size (mu) != sz)))
-      error ("lognrnd: MU and SIGMA must be scalar or of size [R, C]");
-    endif
-
+  if (nargin == 2)
+    sz = size (mu);
   elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      error ("lognrnd: R must be a positive integer or vector");
+      error ("lognrnd: dimension vector must be row vector of non-negative integers");
     endif
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("lognrnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif

-    if (any (size (mu) != 1)
-        && ((length (size (mu)) != length (sz)) || any (size (mu) != sz)))
-      error ("lognrnd: MU and SIGMA must be scalar or of size SZ");
-    endif
-  elseif (nargin == 2)
-    sz = size(mu);
+  if (!isscalar (mu) && !isequal (size (mu), sz))
+    error ("lognrnd: MU and SIGMA must be scalar or of size SZ");
+  endif
+
+  if (isa (mu, "single") || isa (sigma, "single"))
+    cls = "single";
   else
-    print_usage ();
+    cls = "double";
   endif

   if (isscalar (mu) && isscalar (sigma))
-    if  (!(sigma > 0) || !(sigma < Inf))
-      rnd = NaN (sz);
+    if ((sigma > 0) && (sigma < Inf))
+      rnd = exp (mu + sigma * randn (sz));
     else
-      rnd = exp(mu + sigma .* randn (sz));
+      rnd = NaN (sz, cls);
     endif
   else
     rnd = exp (mu + sigma .* randn (sz));
-    k = find ((sigma < 0) | (sigma == Inf));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
+
+    k = (sigma < 0) | (sigma == Inf);
+    rnd(k) = NaN;
   endif

 endfunction
+
+
+%!assert(size (lognrnd (1,2)), [1, 1]);
+%!assert(size (lognrnd (ones(2,1), 2)), [2, 1]);
+%!assert(size (lognrnd (ones(2,2), 2)), [2, 2]);
+%!assert(size (lognrnd (1, 2*ones(2,1))), [2, 1]);
+%!assert(size (lognrnd (1, 2*ones(2,2))), [2, 2]);
+%!assert(size (lognrnd (1, 2, 3)), [3, 3]);
+%!assert(size (lognrnd (1, 2, [4 1])), [4, 1]);
+%!assert(size (lognrnd (1, 2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (lognrnd (1, 2)), "double");
+%!assert(class (lognrnd (single(1), 2)), "single");
+%!assert(class (lognrnd (single([1 1]), 2)), "single");
+%!assert(class (lognrnd (1, single(2))), "single");
+%!assert(class (lognrnd (1, single([2 2]))), "single");
+
+%% Test input validation
+%!error lognrnd ()
+%!error lognrnd (1)
+%!error lognrnd (ones(3),ones(2))
+%!error lognrnd (ones(2),ones(3))
+%!error lognrnd (i, 2)
+%!error lognrnd (2, i)
+%!error lognrnd (1,2, -1)
+%!error lognrnd (1,2, ones(2))
+%!error lognrnd (1, 2, [2 -1 2])
+%!error lognrnd (1,2, 1, ones(2))
+%!error lognrnd (1,2, 1, -1)
+%!error lognrnd (ones(2,2), 2, 3)
+%!error lognrnd (ones(2,2), 2, [3, 2])
+%!error lognrnd (ones(2,2), 2, 2, 3)
+
--- a/scripts/statistics/distributions/nbincdf.m
+++ b/scripts/statistics/distributions/nbincdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,9 +19,13 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} nbincdf (@var{x}, @var{n}, @var{p})
-## For each element of @var{x}, compute the CDF at x of the Pascal
-## (negative binomial) distribution with parameters @var{n} and @var{p}.
+## For each element of @var{x}, compute the cumulative distribution function
+## (CDF) at @var{x} of the negative binomial distribution with
+## parameters @var{n} and @var{p}.
 ##
+## When @var{n} is integer this is the Pascal distribution.  When
+## @var{n} is extended to real numbers this is the Polya distribution.
+##
 ## The number of failures in a Bernoulli experiment with success
 ## probability @var{p} before the @var{n}-th success follows this
 ## distribution.
@@ -35,58 +40,66 @@
     print_usage ();
   endif

-  if (!isscalar(n) || !isscalar(p))
+  if (!isscalar (n) || !isscalar (p))
     [retval, x, n, p] = common_size (x, n, p);
     if (retval > 0)
-      error ("nbincdf: X, N and P must be of common size or scalar");
+      error ("nbincdf: X, N, and P must be of common size or scalars");
     endif
   endif

-  cdf = zeros (size (x));
-
-  k = find (isnan (x) | (n < 1) | (n == Inf) | (n != round (n))
-            | (p < 0) | (p > 1));
-  if (any (k))
-    cdf(k) = NaN;
+  if (iscomplex (x) || iscomplex (n) || iscomplex (p))
+    error ("nbincdf: X, N, and P must not be complex");
   endif

-  k = find ((x == Inf) & (n > 0) & (n < Inf) & (n == round (n))
-            & (p >= 0) & (p <= 1));
-  if (any (k))
-    cdf(k) = 1;
+  if (isa (x, "single") || isa (n, "single") || isa (p, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x >= 0) & (x < Inf) & (x == round (x)) & (n > 0)
-            & (n < Inf) & (n == round (n)) & (p > 0) & (p <= 1));
-  if (any (k))
-    ## Does anyone know a better way to do the summation?
-    m = zeros (size (k));
-    x = floor (x(k));
-    y = cdf(k);
-    if (isscalar (n) && isscalar (p))
-      while (1)
-        l = find (m <= x);
-        if (any (l))
-          y(l) = y(l) + nbinpdf (m(l), n, p);
-          m(l) = m(l) + 1;
-        else
-          break;
-        endif
-      endwhile
-    else
-      n = n(k);
-      p = p(k);
-      while (1)
-        l = find (m <= x);
-        if (any (l))
-          y(l) = y(l) + nbinpdf (m(l), n(l), p(l));
-          m(l) = m(l) + 1;
-        else
-          break;
-        endif
-      endwhile
-    endif
-    cdf(k) = y;
+  k = (isnan (x) | isnan (n) | (n < 1) | (n == Inf)
+       | (p < 0) | (p > 1) | isnan (p));
+  cdf(k) = NaN;
+
+  k = (x == Inf) & (n > 0) & (n < Inf) & (p >= 0) & (p <= 1);
+  cdf(k) = 1;
+
+  k = ((x >= 0) & (x < Inf) & (x == fix (x))
+       & (n > 0) & (n < Inf) & (p > 0) & (p <= 1));
+  if (isscalar (n) && isscalar (p))
+    cdf(k) = 1 - betainc (1-p, x(k)+1, n);
+  else
+    cdf(k) = 1 - betainc (1-p(k), x(k)+1, n(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 2 Inf];
+%! y = [0 1/2 3/4 7/8 1];
+%!assert(nbincdf (x, ones(1,5), 0.5*ones(1,5)), y);
+%!assert(nbincdf (x, 1, 0.5*ones(1,5)), y);
+%!assert(nbincdf (x, ones(1,5), 0.5), y);
+%!assert(nbincdf ([x(1:3) 0 x(5)], [0 1 NaN 1.5 Inf], 0.5), [NaN 1/2 NaN nbinpdf(0,1.5,0.5) NaN], eps);
+%!assert(nbincdf (x, 1, 0.5*[-1 NaN 4 1 1]), [NaN NaN NaN y(4:5)]);
+%!assert(nbincdf ([x(1:2) NaN x(4:5)], 1, 0.5), [y(1:2) NaN y(4:5)]);
+
+%% Test class of input preserved
+%!assert(nbincdf ([x, NaN], 1, 0.5), [y, NaN]);
+%!assert(nbincdf (single([x, NaN]), 1, 0.5), single([y, NaN]));
+%!assert(nbincdf ([x, NaN], single(1), 0.5), single([y, NaN]));
+%!assert(nbincdf ([x, NaN], 1, single(0.5)), single([y, NaN]));
+
+%% Test input validation
+%!error nbincdf ()
+%!error nbincdf (1)
+%!error nbincdf (1,2)
+%!error nbincdf (1,2,3,4)
+%!error nbincdf (ones(3),ones(2),ones(2))
+%!error nbincdf (ones(2),ones(3),ones(2))
+%!error nbincdf (ones(2),ones(2),ones(3))
+%!error nbincdf (i, 2, 2)
+%!error nbincdf (2, i, 2)
+%!error nbincdf (2, 2, i)
+
--- a/scripts/statistics/distributions/nbininv.m
+++ b/scripts/statistics/distributions/nbininv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,10 +19,13 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} nbininv (@var{x}, @var{n}, @var{p})
-## For each element of @var{x}, compute the quantile at @var{x} of the
-## Pascal (negative binomial) distribution with parameters @var{n} and
-## @var{p}.
+## For each element of @var{x}, compute the quantile (the inverse of
+## the CDF) at @var{x} of the negative binomial distribution
+## with parameters @var{n} and @var{p}.
 ##
+## When @var{n} is integer this is the Pascal distribution.  When
+## @var{n} is extended to real numbers this is the Polya distribution.
+##
 ## The number of failures in a Bernoulli experiment with success
 ## probability @var{p} before the @var{n}-th success follows this
 ## distribution.
@@ -36,58 +40,89 @@
     print_usage ();
   endif

-  if (!isscalar(n) || !isscalar(p))
+  if (!isscalar (n) || !isscalar (p))
     [retval, x, n, p] = common_size (x, n, p);
     if (retval > 0)
-      error ("nbininv: X, N and P must be of common size or scalar");
+      error ("nbininv: X, N, and P must be of common size or scalars");
     endif
   endif

-  inv = zeros (size (x));
-
-  k = find (isnan (x) | (x < 0) | (x > 1) | (n < 1) | (n == Inf)
-            | (n != round (n)) | (p < 0) | (p > 1));
-  if (any (k))
-    inv(k) = NaN;
+  if (iscomplex (x) || iscomplex (n) || iscomplex (p))
+    error ("nbininv: X, N, and P must not be complex");
   endif

-  k = find ((x == 1) & (n > 0) & (n < Inf) & (n == round (n))
-            & (p >= 0) & (p <= 1));
-  if (any (k))
-    inv(k) = Inf;
+  if (isa (x, "single") || isa (n, "single") || isa (p, "single"))
+    inv = zeros (size (x), "single");
+  else
+    inv = zeros (size (x));
   endif

+  k = (isnan (x) | (x < 0) | (x > 1) | isnan (n) | (n < 1) | (n == Inf)
+       | isnan (p) | (p < 0) | (p > 1));
+  inv(k) = NaN;
+
+  k = (x == 1) & (n > 0) & (n < Inf) & (p >= 0) & (p <= 1);
+  inv(k) = Inf;
+
   k = find ((x >= 0) & (x < 1) & (n > 0) & (n < Inf)
-            & (n == round (n)) & (p > 0) & (p <= 1));
-  if (any (k))
-    m = zeros (size (k));
-    x = x(k);
-    if (isscalar (n) && isscalar (p))
-      s = p ^ n * ones (size(k));
-      while (1)
-        l = find (s < x);
-        if (any (l))
-          m(l) = m(l) + 1;
-          s(l) = s(l) + nbinpdf (m(l), n, p);
-        else
-          break;
-        endif
-      endwhile
-    else
-      n = n(k);
-      p = p(k);
-      s = p .^ n;
-      while (1)
-        l = find (s < x);
-        if (any (l))
-          m(l) = m(l) + 1;
-          s(l) = s(l) + nbinpdf (m(l), n(l), p(l));
-        else
-          break;
-        endif
-      endwhile
-    endif
-    inv(k) = m;
+            & (p > 0) & (p <= 1));
+  m = zeros (size (k));
+  x = x(k);
+  if (isscalar (n) && isscalar (p))
+    s = p ^ n * ones (size (k));
+    while (1)
+      l = find (s < x);
+      if (any (l))
+        m(l) = m(l) + 1;
+        s(l) = s(l) + nbinpdf (m(l), n, p);
+      else
+        break;
+      endif
+    endwhile
+  else
+    n = n(k);
+    p = p(k);
+    s = p .^ n;
+    while (1)
+      l = find (s < x);
+      if (any (l))
+        m(l) = m(l) + 1;
+        s(l) = s(l) + nbinpdf (m(l), n(l), p(l));
+      else
+        break;
+      endif
+    endwhile
   endif
+  inv(k) = m;

 endfunction
+
+
+%!shared x
+%! x = [-1 0 3/4 1 2];
+%!assert(nbininv (x, ones(1,5), 0.5*ones(1,5)), [NaN 0 1 Inf NaN]);
+%!assert(nbininv (x, 1, 0.5*ones(1,5)), [NaN 0 1 Inf NaN]);
+%!assert(nbininv (x, ones(1,5), 0.5), [NaN 0 1 Inf NaN]);
+%!assert(nbininv (x, [1 0 NaN Inf 1], 0.5), [NaN NaN NaN NaN NaN]);
+%!assert(nbininv (x, [1 0 1.5 Inf 1], 0.5), [NaN NaN 2 NaN NaN]);
+%!assert(nbininv (x, 1, 0.5*[1 -Inf NaN Inf 1]), [NaN NaN NaN NaN NaN]);
+%!assert(nbininv ([x(1:2) NaN x(4:5)], 1, 0.5), [NaN 0 NaN Inf NaN]);
+
+%% Test class of input preserved
+%!assert(nbininv ([x, NaN], 1, 0.5), [NaN 0 1 Inf NaN NaN]);
+%!assert(nbininv (single([x, NaN]), 1, 0.5), single([NaN 0 1 Inf NaN NaN]));
+%!assert(nbininv ([x, NaN], single(1), 0.5), single([NaN 0 1 Inf NaN NaN]));
+%!assert(nbininv ([x, NaN], 1, single(0.5)), single([NaN 0 1 Inf NaN NaN]));
+
+%% Test input validation
+%!error nbininv ()
+%!error nbininv (1)
+%!error nbininv (1,2)
+%!error nbininv (1,2,3,4)
+%!error nbininv (ones(3),ones(2),ones(2))
+%!error nbininv (ones(2),ones(3),ones(2))
+%!error nbininv (ones(2),ones(2),ones(3))
+%!error nbininv (i, 2, 2)
+%!error nbininv (2, i, 2)
+%!error nbininv (2, 2, i)
+
--- a/scripts/statistics/distributions/nbinpdf.m
+++ b/scripts/statistics/distributions/nbinpdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -19,9 +20,12 @@
 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} nbinpdf (@var{x}, @var{n}, @var{p})
 ## For each element of @var{x}, compute the probability density function
-## (PDF) at @var{x} of the Pascal (negative binomial) distribution with
+## (PDF) at @var{x} of the negative binomial distribution with
 ## parameters @var{n} and @var{p}.
 ##
+## When @var{n} is integer this is the Pascal distribution.  When
+## @var{n} is extended to real numbers this is the Polya distribution.
+##
 ## The number of failures in a Bernoulli experiment with success
 ## probability @var{p} before the @var{n}-th success follows this
 ## distribution.
@@ -36,36 +40,63 @@
     print_usage ();
   endif

-  if (!isscalar(n) || !isscalar(p))
+  if (!isscalar (n) || !isscalar (p))
     [retval, x, n, p] = common_size (x, n, p);
     if (retval > 0)
-      error ("nbinpdf: X, N and P must be of common size or scalar");
+      error ("nbinpdf: X, N, and P must be of common size or scalars");
     endif
   endif

-  pdf = zeros (size (x));
+  if (iscomplex (x) || iscomplex (n) || iscomplex (p))
+    error ("nbinpdf: X, N, and P must not be complex");
+  endif

-  k = find (isnan (x) | (n < 1) | (n == Inf) | (n != round (n))
-            | (p < 0) | (p > 1));
-  if (any (k))
-    pdf(k) = NaN;
+  if (isa (x, "single") || isa (n, "single") || isa (p, "single"))
+    pdf = NaN (size (x), "single");
+  else
+    pdf = NaN (size (x));
   endif

-  ## Just for the fun of it ...
-  k = find ((x == Inf) & (n > 0) & (n < Inf) & (n == round (n))
-            & (p == 0));
-  if (any (k))
-    pdf(k) = 1;
-  endif
+  ok = (x < Inf) & (x == fix (x)) & (n > 0) & (n < Inf) & (p >= 0) & (p <= 1);
+
+  k = (x < 0) & ok;
+  pdf(k) = 0;

-  k = find ((x >= 0) & (x < Inf) & (x == round (x)) & (n > 0)
-            & (n < Inf) & (n == round (n)) & (p > 0) & (p <= 1));
-  if (any (k))
-    if (isscalar (n) && isscalar (p))
-      pdf(k) = bincoeff (-n, x(k)) .* (p ^ n) .* ((p - 1) .^ x(k));
-    else
-      pdf(k) = bincoeff (-n(k), x(k)) .* (p(k) .^ n(k)) .* ((p(k) - 1) .^ x(k));
-    endif
+  k = (x >= 0) & ok;
+  if (isscalar (n) && isscalar (p))
+    pdf(k) = bincoeff (-n, x(k)) .* (p ^ n) .* ((p - 1) .^ x(k));
+  else
+    pdf(k) = bincoeff (-n(k), x(k)) .* (p(k) .^ n(k)) .* ((p(k) - 1) .^ x(k));
   endif
+

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 2 Inf];
+%! y = [0 1/2 1/4 1/8 NaN];
+%!assert(nbinpdf (x, ones(1,5), 0.5*ones(1,5)), y);
+%!assert(nbinpdf (x, 1, 0.5*ones(1,5)), y);
+%!assert(nbinpdf (x, ones(1,5), 0.5), y);
+%!assert(nbinpdf (x, [0 1 NaN 1.5 Inf], 0.5), [NaN 1/2 NaN 1.875*0.5^1.5/4 NaN], eps);
+%!assert(nbinpdf (x, 1, 0.5*[-1 NaN 4 1 1]), [NaN NaN NaN y(4:5)]);
+%!assert(nbinpdf ([x, NaN], 1, 0.5), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(nbinpdf (single([x, NaN]), 1, 0.5), single([y, NaN]));
+%!assert(nbinpdf ([x, NaN], single(1), 0.5), single([y, NaN]));
+%!assert(nbinpdf ([x, NaN], 1, single(0.5)), single([y, NaN]));
+
+%% Test input validation
+%!error nbinpdf ()
+%!error nbinpdf (1)
+%!error nbinpdf (1,2)
+%!error nbinpdf (1,2,3,4)
+%!error nbinpdf (ones(3),ones(2),ones(2))
+%!error nbinpdf (ones(2),ones(3),ones(2))
+%!error nbinpdf (ones(2),ones(2),ones(3))
+%!error nbinpdf (i, 2, 2)
+%!error nbinpdf (2, i, 2)
+%!error nbinpdf (2, 2, i)
+
--- a/scripts/statistics/distributions/nbinrnd.m
+++ b/scripts/statistics/distributions/nbinrnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,85 +18,123 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} nbinrnd (@var{n}, @var{p}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} nbinrnd (@var{n}, @var{p}, @var{sz})
-## Return an @var{r} by @var{c} matrix of random samples from the Pascal
-## (negative binomial) distribution with parameters @var{n} and @var{p}.
-## Both @var{n} and @var{p} must be scalar or of size @var{r} by @var{c}.
+## @deftypefn  {Function File} {} nbinrnd (@var{n}, @var{p})
+## @deftypefnx {Function File} {} nbinrnd (@var{n}, @var{p}, @var{r})
+## @deftypefnx {Function File} {} nbinrnd (@var{n}, @var{p}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} nbinrnd (@var{n}, @var{p}, [@var{sz}])
+## Return a matrix of random samples from the negative binomial
+## distribution with parameters @var{n} and @var{p}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{n} and @var{p}.  Or if @var{sz} is a vector,
-## create a matrix of size @var{sz}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{n} and @var{p}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the Pascal distribution

-function rnd = nbinrnd (n, p, r, c)
+function rnd = nbinrnd (n, p, varargin)

-  if (nargin > 1)
-    if (!isscalar(n) || !isscalar(p))
-      [retval, n, p] = common_size (n, p);
-      if (retval > 0)
-        error ("nbinrnd: N and P must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (n) || !isscalar (p))
+    [retval, n, p] = common_size (n, p);
+    if (retval > 0)
+      error ("nbinrnd: N and P must be of common size or scalars");
     endif
   endif

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("nbinrnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("nbinrnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+  if (iscomplex (n) || iscomplex (p))
+    error ("nbinrnd: N and P must not be complex");
+  endif

-    if (any (size (n) != 1)
-        && ((length (size (n)) != length (sz)) || any (size (n) != sz)))
-      error ("nbinrnd: N and P must be scalar or of size [R, C]");
-    endif
-
+  if (nargin == 2)
+    sz = size (n);
   elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      error ("nbinrnd: R must be a positive integer or vector");
+      error ("nbinrnd: dimension vector must be row vector of non-negative integers");
     endif
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("nbinrnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif

-    if (any (size (n) != 1)
-        && ((length (size (n)) != length (sz)) || any (size (n) != sz)))
-      error ("nbinrnd: N and P must be scalar or of size SZ");
-    endif
-  elseif (nargin == 2)
-    sz = size(n);
+  if (!isscalar (n) && !isequal (size (n), sz))
+    error ("nbinrnd: N and P must be scalar or of size SZ");
+  endif
+
+  if (isa (n, "single") || isa (p, "single"))
+    cls = "single";
   else
-    print_usage ();
+    cls = "double";
   endif

   if (isscalar (n) && isscalar (p))
-    if ((n < 1) || (n == Inf) || (n != round (n)) || (p <= 0) || (p > 1));
-      rnd = NaN (sz);
-    elseif ((n > 0) && (n < Inf) && (n == round (n))
-            && (p > 0) && (p <= 1))
+    if ((n > 0) && (n < Inf) && (p > 0) && (p <= 1))
       rnd = randp ((1 - p) ./ p .* randg (n, sz));
+      if (strcmp (cls, "single"))
+        rnd = single (rnd);
+      endif
+    elseif ((n > 0) && (n < Inf) && (p == 0))
+      rnd = zeros (sz, cls);
     else
-      rnd = zeros (sz);
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = zeros (sz);
+    rnd = NaN (sz, cls);

-    k = find ((n < 1) | (n == Inf) | (n != round (n)) | (p <= 0) | (p > 1));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
+    k = (n > 0) & (n < Inf) & (p == 0);
+    rnd(k) = 0;

-    k = find ((n > 0) & (n < Inf) & (n == round (n)) & (p > 0) & (p <= 1));
-    if (any (k))
-      rnd(k) = randp ((1 - p(k)) ./ p(k) .* randg (n(k), size(k)));
-    endif
+    k = (n > 0) & (n < Inf) & (p > 0) & (p <= 1);
+    rnd(k) = randp ((1 - p(k)) ./ p(k) .* randg (n(k)));
   endif

 endfunction
+
+
+%!assert(size (nbinrnd (2, 1/2)), [1, 1]);
+%!assert(size (nbinrnd (2*ones(2,1), 1/2)), [2, 1]);
+%!assert(size (nbinrnd (2*ones(2,2), 1/2)), [2, 2]);
+%!assert(size (nbinrnd (2, 1/2*ones(2,1))), [2, 1]);
+%!assert(size (nbinrnd (2, 1/2*ones(2,2))), [2, 2]);
+%!assert(size (nbinrnd (2, 1/2, 3)), [3, 3]);
+%!assert(size (nbinrnd (2, 1/2, [4 1])), [4, 1]);
+%!assert(size (nbinrnd (2, 1/2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (nbinrnd (2, 1/2)), "double");
+%!assert(class (nbinrnd (single(2), 1/2)), "single");
+%!assert(class (nbinrnd (single([2 2]), 1/2)), "single");
+%!assert(class (nbinrnd (2, single(1/2))), "single");
+%!assert(class (nbinrnd (2, single([1/2 1/2]))), "single");
+
+%% Test input validation
+%!error nbinrnd ()
+%!error nbinrnd (1)
+%!error nbinrnd (ones(3),ones(2))
+%!error nbinrnd (ones(2),ones(3))
+%!error nbinrnd (i, 2)
+%!error nbinrnd (2, i)
+%!error nbinrnd (1,2, -1)
+%!error nbinrnd (1,2, ones(2))
+%!error nbinrnd (1, 2, [2 -1 2])
+%!error nbinrnd (1,2, 1, ones(2))
+%!error nbinrnd (1,2, 1, -1)
+%!error nbinrnd (ones(2,2), 2, 3)
+%!error nbinrnd (ones(2,2), 2, [3, 2])
+%!error nbinrnd (ones(2,2), 2, 2, 3)
+
--- a/scripts/statistics/distributions/normcdf.m
+++ b/scripts/statistics/distributions/normcdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,56 +18,82 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} normcdf (@var{x}, @var{m}, @var{s})
+## @deftypefn  {Function File} {} normcdf (@var{x})
+## @deftypefnx {Function File} {} normcdf (@var{x}, @var{mu}, @var{sigma})
 ## For each element of @var{x}, compute the cumulative distribution
 ## function (CDF) at @var{x} of the normal distribution with mean
-## @var{m} and standard deviation @var{s}.
+## @var{mu} and standard deviation @var{sigma}.
 ##
-## Default values are @var{m} = 0, @var{s} = 1.
+## Default values are @var{mu} = 0, @var{sigma} = 1.
 ## @end deftypefn

 ## Author: TT <Teresa.Twaroch@ci.tuwien.ac.at>
 ## Description: CDF of the normal distribution

-function cdf = normcdf (x, m, s)
+function cdf = normcdf (x, mu = 0, sigma = 1)

-  if (! ((nargin == 1) || (nargin == 3)))
+  if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    m = 0;
-    s = 1;
-  endif
-
-  if (!isscalar (m) || !isscalar (s))
-    [retval, x, m, s] = common_size (x, m, s);
+  if (!isscalar (mu) || !isscalar (sigma))
+    [retval, x, mu, sigma] = common_size (x, mu, sigma);
     if (retval > 0)
-      error ("normcdf: X, M and S must be of common size or scalar");
+      error ("normcdf: X, MU, and SIGMA must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  cdf = zeros (sz);
+  if (iscomplex (x) || iscomplex (mu) || iscomplex (sigma))
+    error ("normcdf: X, MU, and SIGMA must not be complex");
+  endif

-  if (isscalar (m) && isscalar(s))
-    if (find (isinf (m) | isnan (m) | !(s > 0) | !(s < Inf)))
-      cdf = NaN (sz);
+  if (isa (x, "single") || isa (mu, "single") || isa (sigma, "single"));
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
+  endif
+
+  if (isscalar (mu) && isscalar (sigma))
+    if (!isinf (mu) && !isnan (mu) && (sigma > 0) && (sigma < Inf))
+      cdf = stdnormal_cdf ((x - mu) / sigma);
     else
-      cdf =  stdnormal_cdf ((x - m) ./ s);
+      cdf = NaN (size (x), class (cdf));
     endif
   else
-    k = find (isinf (m) | isnan (m) | !(s > 0) | !(s < Inf));
-    if (any (k))
-      cdf(k) = NaN;
-    endif
+    k = isinf (mu) | isnan (mu) | !(sigma > 0) | !(sigma < Inf);
+    cdf(k) = NaN;

-    k = find (!isinf (m) & !isnan (m) & (s > 0) & (s < Inf));
-    if (any (k))
-      cdf(k) = stdnormal_cdf ((x(k) - m(k)) ./ s(k));
-    endif
+    k = ! k;
+    cdf(k) = stdnormal_cdf ((x(k) - mu(k)) ./ sigma(k));
   endif

-  cdf((s == 0) & (x == m)) = 0.5;
+endfunction
+
+
+%!shared x,y
+%! x = [-Inf 1 2 Inf];
+%! y = [0, 0.5, 1/2*(1+erf(1/sqrt(2))), 1];
+%!assert(normcdf (x, ones(1,4), ones(1,4)), y);
+%!assert(normcdf (x, 1, ones(1,4)), y);
+%!assert(normcdf (x, ones(1,4), 1), y);
+%!assert(normcdf (x, [0 -Inf NaN Inf], 1), [y(1) NaN NaN NaN]);
+%!assert(normcdf (x, 1, [Inf NaN -1 0]), [NaN NaN NaN NaN]);
+%!assert(normcdf ([x(1:2) NaN x(4)], 1, 1), [y(1:2) NaN y(4)]);

-endfunction
+%% Test class of input preserved
+%!assert(normcdf ([x, NaN], 1, 1), [y, NaN]);
+%!assert(normcdf (single([x, NaN]), 1, 1), single([y, NaN]), eps("single"));
+%!assert(normcdf ([x, NaN], single(1), 1), single([y, NaN]), eps("single"));
+%!assert(normcdf ([x, NaN], 1, single(1)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error normcdf ()
+%!error normcdf (1,2)
+%!error normcdf (1,2,3,4)
+%!error normcdf (ones(3),ones(2),ones(2))
+%!error normcdf (ones(2),ones(3),ones(2))
+%!error normcdf (ones(2),ones(2),ones(3))
+%!error normcdf (i, 2, 2)
+%!error normcdf (2, i, 2)
+%!error normcdf (2, 2, i)
+
--- a/scripts/statistics/distributions/norminv.m
+++ b/scripts/statistics/distributions/norminv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,62 +18,76 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} norminv (@var{x}, @var{m}, @var{s})
+## @deftypefn  {Function File} {} norminv (@var{x})
+## @deftypefnx {Function File} {} norminv (@var{x}, @var{mu}, @var{sigma})
 ## For each element of @var{x}, compute the quantile (the inverse of the
-## CDF) at @var{x} of the normal distribution with mean @var{m} and
-## standard deviation @var{s}.
+## CDF) at @var{x} of the normal distribution with mean @var{mu} and
+## standard deviation @var{sigma}.
 ##
-## Default values are @var{m} = 0, @var{s} = 1.
+## Default values are @var{mu} = 0, @var{sigma} = 1.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Quantile function of the normal distribution

-function inv = norminv (x, m, s)
+function inv = norminv (x, mu = 0, sigma = 1)

   if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    m = 0;
-    s = 1;
-  endif
-
-  if (!isscalar (m) || !isscalar (s))
-    [retval, x, m, s] = common_size (x, m, s);
+  if (!isscalar (mu) || !isscalar (sigma))
+    [retval, x, mu, sigma] = common_size (x, mu, sigma);
     if (retval > 0)
-      error ("norminv: X, M and S must be of common size or scalars");
+      error ("norminv: X, MU, and SIGMA must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  inv = zeros (sz);
+  if (iscomplex (x) || iscomplex (mu) || iscomplex (sigma))
+    error ("norminv: X, MU, and SIGMA must not be complex");
+  endif

-  if (isscalar (m) && isscalar (s))
-    if (find (isinf (m) | isnan (m) | !(s > 0) | !(s < Inf)))
-      inv = NaN (sz);
-    else
-      inv =  m + s .* stdnormal_inv (x);
+  if (isa (x, "single") || isa (mu, "single") || isa (sigma, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
+  endif
+
+  if (isscalar (mu) && isscalar (sigma))
+    if (!isinf (mu) && !isnan (mu) && (sigma > 0) && (sigma < Inf))
+      inv =  mu + sigma * stdnormal_inv (x);
     endif
   else
-    k = find (isinf (m) | isnan (m) | !(s > 0) | !(s < Inf));
-    if (any (k))
-      inv(k) = NaN;
-    endif
-
-    k = find (!isinf (m) & !isnan (m) & (s > 0) & (s < Inf));
-    if (any (k))
-      inv(k) = m(k) + s(k) .* stdnormal_inv (x(k));
-    endif
+    k = !isinf (mu) & !isnan (mu) & (sigma > 0) & (sigma < Inf);
+    inv(k) = mu(k) + sigma(k) .* stdnormal_inv (x(k));
   endif

-  k = find ((s == 0) & (x > 0) & (x < 1));
-  if (any (k))
-    inv(k) = m(k);
-  endif
+endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(norminv (x, ones(1,5), ones(1,5)), [NaN -Inf 1 Inf NaN]);
+%!assert(norminv (x, 1, ones(1,5)), [NaN -Inf 1 Inf NaN]);
+%!assert(norminv (x, ones(1,5), 1), [NaN -Inf 1 Inf NaN]);
+%!assert(norminv (x, [1 -Inf NaN Inf 1], 1), [NaN NaN NaN NaN NaN]);
+%!assert(norminv (x, 1, [1 0 NaN Inf 1]), [NaN NaN NaN NaN NaN]);
+%!assert(norminv ([x(1:2) NaN x(4:5)], 1, 1), [NaN -Inf NaN Inf NaN]);

-  inv((s == 0) & (x == 0)) = -Inf;
-  inv((s == 0) & (x == 1)) = Inf;
+%% Test class of input preserved
+%!assert(norminv ([x, NaN], 1, 1), [NaN -Inf 1 Inf NaN NaN]);
+%!assert(norminv (single([x, NaN]), 1, 1), single([NaN -Inf 1 Inf NaN NaN]));
+%!assert(norminv ([x, NaN], single(1), 1), single([NaN -Inf 1 Inf NaN NaN]));
+%!assert(norminv ([x, NaN], 1, single(1)), single([NaN -Inf 1 Inf NaN NaN]));

-endfunction
+%% Test input validation
+%!error norminv ()
+%!error norminv (1,2)
+%!error norminv (1,2,3,4)
+%!error norminv (ones(3),ones(2),ones(2))
+%!error norminv (ones(2),ones(3),ones(2))
+%!error norminv (ones(2),ones(2),ones(3))
+%!error norminv (i, 2, 2)
+%!error norminv (2, i, 2)
+%!error norminv (2, 2, i)
+
--- a/scripts/statistics/distributions/normpdf.m
+++ b/scripts/statistics/distributions/normpdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,57 +18,81 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} normpdf (@var{x}, @var{m}, @var{s})
+## @deftypefn  {Function File} {} normpdf (@var{x})
+## @deftypefnx {Function File} {} normpdf (@var{x}, @var{mu}, @var{sigma})
 ## For each element of @var{x}, compute the probability density function
-## (PDF) at @var{x} of the normal distribution with mean @var{m} and
-## standard deviation @var{s}.
+## (PDF) at @var{x} of the normal distribution with mean @var{mu} and
+## standard deviation @var{sigma}.
 ##
-## Default values are @var{m} = 0, @var{s} = 1.
+## Default values are @var{mu} = 0, @var{sigma} = 1.
 ## @end deftypefn

 ## Author: TT <Teresa.Twaroch@ci.tuwien.ac.at>
 ## Description: PDF of the normal distribution

-function pdf = normpdf (x, m, s)
+function pdf = normpdf (x, mu = 0, sigma = 1)

   if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    m = 0;
-    s = 1;
-  endif
-
-  if (!isscalar (m) || !isscalar (s))
-    [retval, x, m, s] = common_size (x, m, s);
+  if (!isscalar (mu) || !isscalar (sigma))
+    [retval, x, mu, sigma] = common_size (x, mu, sigma);
     if (retval > 0)
-      error ("normpdf: X, M and S must be of common size or scalars");
+      error ("normpdf: X, MU, and SIGMA must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  pdf = zeros (sz);
+  if (iscomplex (x) || iscomplex (mu) || iscomplex (sigma))
+    error ("normpdf: X, MU, and SIGMA must not be complex");
+  endif

-  if (isscalar (m) && isscalar (s))
-    if (find (isinf (m) | isnan (m) | !(s > 0) | !(s < Inf)))
-      pdf = NaN (sz);
+  if (isa (x, "single") || isa (mu, "single") || isa (sigma, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
+  endif
+
+  if (isscalar (mu) && isscalar (sigma))
+    if (!isinf (mu) && !isnan (mu) && (sigma > 0) && (sigma < Inf))
+      pdf = stdnormal_pdf ((x - mu) / sigma) / sigma;
     else
-      pdf = stdnormal_pdf ((x - m) ./ s) ./ s;
+      pdf = NaN (size (x), class (pdf));
     endif
   else
-    k = find (isinf (m) | isnan (m) | !(s > 0) | !(s < Inf));
-    if (any (k))
-      pdf(k) = NaN;
-    endif
+    k = isinf (mu) | !(sigma > 0) | !(sigma < Inf);
+    pdf(k) = NaN;

-    k = find (!isinf (m) & !isnan (m) & (s > 0) & (s < Inf));
-    if (any (k))
-      pdf(k) = stdnormal_pdf ((x(k) - m(k)) ./ s(k)) ./ s(k);
-    endif
+    k = !isinf (mu) & (sigma > 0) & (sigma < Inf);
+    pdf(k) = stdnormal_pdf ((x(k) - mu(k)) ./ sigma(k)) ./ sigma(k);
   endif

-  pdf((s == 0) & (x == m)) = Inf;
-  pdf((s == 0) & ((x < m) | (x > m))) = 0;
+endfunction
+
+
+%!shared x,y
+%! x = [-Inf 1 2 Inf];
+%! y = 1/sqrt(2*pi)*exp (-(x-1).^2/2);
+%!assert(normpdf (x, ones(1,4), ones(1,4)), y);
+%!assert(normpdf (x, 1, ones(1,4)), y);
+%!assert(normpdf (x, ones(1,4), 1), y);
+%!assert(normpdf (x, [0 -Inf NaN Inf], 1), [y(1) NaN NaN NaN]);
+%!assert(normpdf (x, 1, [Inf NaN -1 0]), [NaN NaN NaN NaN]);
+%!assert(normpdf ([x, NaN], 1, 1), [y, NaN]);

-endfunction
+%% Test class of input preserved
+%!assert(normpdf (single([x, NaN]), 1, 1), single([y, NaN]), eps("single"));
+%!assert(normpdf ([x, NaN], single(1), 1), single([y, NaN]), eps("single"));
+%!assert(normpdf ([x, NaN], 1, single(1)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error normpdf ()
+%!error normpdf (1,2)
+%!error normpdf (1,2,3,4)
+%!error normpdf (ones(3),ones(2),ones(2))
+%!error normpdf (ones(2),ones(3),ones(2))
+%!error normpdf (ones(2),ones(2),ones(3))
+%!error normpdf (i, 2, 2)
+%!error normpdf (2, i, 2)
+%!error normpdf (2, 2, i)
+
--- a/scripts/statistics/distributions/normrnd.m
+++ b/scripts/statistics/distributions/normrnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,75 +18,114 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} normrnd (@var{m}, @var{s}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} normrnd (@var{m}, @var{s}, @var{sz})
-## Return an @var{r} by @var{c}  or @code{size (@var{sz})} matrix of
-## random samples from the normal distribution with parameters mean @var{m}
-## and standard deviation @var{s}.  Both @var{m} and @var{s} must be scalar
-## or of size @var{r} by @var{c}.
+## @deftypefn  {Function File} {} normrnd (@var{mu}, @var{sigma})
+## @deftypefnx {Function File} {} normrnd (@var{mu}, @var{sigma}, @var{r})
+## @deftypefnx {Function File} {} normrnd (@var{mu}, @var{sigma}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} normrnd (@var{mu}, @var{sigma}, [@var{sz}])
+## Return a matrix of random samples from the normal distribution with
+## parameters mean @var{mu} and standard deviation @var{sigma}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{m} and @var{s}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{mu} and @var{sigma}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the normal distribution

-function rnd = normrnd (m, s, r, c)
+function rnd = normrnd (mu, sigma, varargin)

-  if (nargin > 1)
-    if (!isscalar (m) || !isscalar (s))
-      [retval, m, s] = common_size (m, s);
-      if (retval > 0)
-        error ("normrnd: M and S must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (mu) || !isscalar (sigma))
+    [retval, mu, sigma] = common_size (mu, sigma);
+    if (retval > 0)
+      error ("normrnd: mu and sigma must be of common size or scalars");
     endif
   endif

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("normrnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("normrnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+  if (iscomplex (mu) || iscomplex (sigma))
+    error ("normrnd: MU and SIGMA must not be complex");
+  endif

-    if (any (size (m) != 1)
-        && (length (size (m)) != length (sz) || any (size (m) != sz)))
-      error ("normrnd: M and S must be scalar or of size [R, C]");
-    endif
+  if (nargin == 2)
+    sz = size (mu);
   elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      error ("normrnd: R must be a positive integer or vector");
+      error ("normrnd: dimension vector must be row vector of non-negative integers");
     endif
-
-    if (any (size (m) != 1)
-        && (length (size (m)) != length (sz) || any (size (m) != sz)))
-      error ("normrnd: M and S must be scalar or of size SZ");
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("normrnd: dimensions must be non-negative integers");
     endif
-  elseif (nargin == 2)
-    sz = size(m);
-  else
-    print_usage ();
+    sz = [varargin{:}];
   endif

-  if (isscalar (m) && isscalar (s))
-    if (find (isnan (m) | isinf (m) | !(s > 0) | !(s < Inf)))
-      rnd = NaN (sz);
+  if (!isscalar (mu) && !isequal (size (mu), sz))
+    error ("normrnd: mu and sigma must be scalar or of size SZ");
+  endif
+
+  if (isa (mu, "single") || isa (sigma, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif
+
+  if (isscalar (mu) && isscalar (sigma))
+    if (!isnan (mu) && !isinf (mu) && (sigma > 0) && (sigma < Inf))
+      rnd =  mu + sigma * randn (sz);
     else
-      rnd =  m + s .* randn (sz);
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = m + s .* randn (sz);
-    k = find (isnan (m) | isinf (m) | !(s > 0) | !(s < Inf));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
+    rnd = mu + sigma .* randn (sz);
+    k = isnan (mu) | isinf (mu) | !(sigma > 0) | !(sigma < Inf);
+    rnd(k) = NaN;
   endif

 endfunction
+
+
+%!assert(size (normrnd (1,2)), [1, 1]);
+%!assert(size (normrnd (ones(2,1), 2)), [2, 1]);
+%!assert(size (normrnd (ones(2,2), 2)), [2, 2]);
+%!assert(size (normrnd (1, 2*ones(2,1))), [2, 1]);
+%!assert(size (normrnd (1, 2*ones(2,2))), [2, 2]);
+%!assert(size (normrnd (1, 2, 3)), [3, 3]);
+%!assert(size (normrnd (1, 2, [4 1])), [4, 1]);
+%!assert(size (normrnd (1, 2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (normrnd (1, 2)), "double");
+%!assert(class (normrnd (single(1), 2)), "single");
+%!assert(class (normrnd (single([1 1]), 2)), "single");
+%!assert(class (normrnd (1, single(2))), "single");
+%!assert(class (normrnd (1, single([2 2]))), "single");
+
+%% Test input validation
+%!error normrnd ()
+%!error normrnd (1)
+%!error normrnd (ones(3),ones(2))
+%!error normrnd (ones(2),ones(3))
+%!error normrnd (i, 2)
+%!error normrnd (2, i)
+%!error normrnd (1,2, -1)
+%!error normrnd (1,2, ones(2))
+%!error normrnd (1, 2, [2 -1 2])
+%!error normrnd (1,2, 1, ones(2))
+%!error normrnd (1,2, 1, -1)
+%!error normrnd (ones(2,2), 2, 3)
+%!error normrnd (ones(2,2), 2, [3, 2])
+%!error normrnd (ones(2,2), 2, 2, 3)
+
--- a/scripts/statistics/distributions/poisscdf.m
+++ b/scripts/statistics/distributions/poisscdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -35,29 +36,55 @@
   if (!isscalar (lambda))
     [retval, x, lambda] = common_size (x, lambda);
     if (retval > 0)
-      error ("poisscdf: X and LAMBDA must be of common size or scalar");
+      error ("poisscdf: X and LAMBDA must be of common size or scalars");
     endif
   endif

-  cdf = zeros (size (x));
+  if (iscomplex (x) || iscomplex (lambda))
+    error ("poisscdf: X and LAMBDA must not be complex");
+  endif

-  k = find (isnan (x) | !(lambda > 0));
-  if (any (k))
-    cdf(k) = NaN;
+  if (isa (x, "single") || isa (lambda, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x == Inf) & (lambda > 0));
-  if (any (k))
-    cdf(k) = 1;
-  endif
+  k = isnan (x) | !(lambda > 0);
+  cdf(k) = NaN;
+
+  k = (x == Inf) & (lambda > 0);
+  cdf(k) = 1;

-  k = find ((x >= 0) & (x < Inf) & (lambda > 0));
-  if (any (k))
-    if (isscalar (lambda))
-      cdf(k) = 1 - gammainc (lambda, floor (x(k)) + 1);
-    else
-      cdf(k) = 1 - gammainc (lambda(k), floor (x(k)) + 1);
-    endif
+  k = (x >= 0) & (x < Inf) & (lambda > 0);
+  if (isscalar (lambda))
+    cdf(k) = 1 - gammainc (lambda, floor (x(k)) + 1);
+  else
+    cdf(k) = 1 - gammainc (lambda(k), floor (x(k)) + 1);
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 2 Inf];
+%! y = [0, gammainc(1, (x(2:4) +1), 'upper'), 1];
+%!assert(poisscdf (x, ones(1,5)), y);
+%!assert(poisscdf (x, 1), y);
+%!assert(poisscdf (x, [1 0 NaN 1 1]), [y(1) NaN NaN y(4:5)]);
+%!assert(poisscdf ([x(1:2) NaN Inf x(5)], 1), [y(1:2) NaN 1 y(5)]);
+
+%% Test class of input preserved
+%!assert(poisscdf ([x, NaN], 1), [y, NaN]);
+%!assert(poisscdf (single([x, NaN]), 1), single([y, NaN]), eps("single"));
+%!assert(poisscdf ([x, NaN], single(1)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error poisscdf ()
+%!error poisscdf (1)
+%!error poisscdf (1,2,3)
+%!error poisscdf (ones(3),ones(2))
+%!error poisscdf (ones(2),ones(3))
+%!error poisscdf (i, 2)
+%!error poisscdf (2, i)
+
--- a/scripts/statistics/distributions/poissinv.m
+++ b/scripts/statistics/distributions/poissinv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,7 +19,7 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} poissinv (@var{x}, @var{lambda})
-## For each component of @var{x}, compute the quantile (the inverse of
+## For each element of @var{x}, compute the quantile (the inverse of
 ## the CDF) at @var{x} of the Poisson distribution with parameter
 ## @var{lambda}.
 ## @end deftypefn
@@ -35,42 +36,68 @@
   if (!isscalar (lambda))
     [retval, x, lambda] = common_size (x, lambda);
     if (retval > 0)
-      error ("poissinv: X and LAMBDA must be of common size or scalar");
+      error ("poissinv: X and LAMBDA must be of common size or scalars");
     endif
   endif

-  inv = zeros (size (x));
-
-  k = find ((x < 0) | (x > 1) | isnan (x) | !(lambda > 0));
-  if (any (k))
-    inv(k) = NaN;
+  if (iscomplex (x) || iscomplex (lambda))
+    error ("poissinv: X and LAMBDA must not be complex");
   endif

-  k = find ((x == 1) & (lambda > 0));
-  if (any (k))
-    inv(k) = Inf;
+  if (isa (x, "single") || isa (lambda, "single"))
+    inv = zeros (size (x), "single");
+  else
+    inv = zeros (size (x));
   endif

+  k = (x < 0) | (x > 1) | isnan (x) | !(lambda > 0);
+  inv(k) = NaN;
+
+  k = (x == 1) & (lambda > 0);
+  inv(k) = Inf;
+
   k = find ((x > 0) & (x < 1) & (lambda > 0));
-  if (any (k))
-    if (isscalar (lambda))
-      cdf = exp (-lambda) * ones (size (k));
+  if (isscalar (lambda))
+    cdf = exp (-lambda) * ones (size (k));
+  else
+    cdf = exp (-lambda(k));
+  endif
+
+  while (1)
+    m = find (cdf < x(k));
+    if (any (m))
+      inv(k(m)) += 1;
+      if (isscalar (lambda))
+        cdf(m) = cdf(m) + poisspdf (inv(k(m)), lambda);
+      else
+        cdf(m) = cdf(m) + poisspdf (inv(k(m)), lambda(k(m)));
+      endif
     else
-      cdf = exp (-lambda(k));
+      break;
     endif
-    while (1)
-      m = find (cdf < x(k));
-      if (any (m))
-        inv(k(m)) = inv(k(m)) + 1;
-        if (isscalar (lambda))
-          cdf(m) = cdf(m) + poisspdf (inv(k(m)), lambda);
-        else
-          cdf(m) = cdf(m) + poisspdf (inv(k(m)), lambda(k(m)));
-        endif
-      else
-        break;
-      endif
-    endwhile
-  endif
+  endwhile

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(poissinv (x, ones(1,5)), [NaN 0 1 Inf NaN]);
+%!assert(poissinv (x, 1), [NaN 0 1 Inf NaN]);
+%!assert(poissinv (x, [1 0 NaN 1 1]), [NaN NaN NaN Inf NaN]);
+%!assert(poissinv ([x(1:2) NaN x(4:5)], 1), [NaN 0 NaN Inf NaN]);
+
+%% Test class of input preserved
+%!assert(poissinv ([x, NaN], 1), [NaN 0 1 Inf NaN NaN]);
+%!assert(poissinv (single([x, NaN]), 1), single([NaN 0 1 Inf NaN NaN]));
+%!assert(poissinv ([x, NaN], single(1)), single([NaN 0 1 Inf NaN NaN]));
+
+%% Test input validation
+%!error poissinv ()
+%!error poissinv (1)
+%!error poissinv (1,2,3)
+%!error poissinv (ones(3),ones(2))
+%!error poissinv (ones(2),ones(3))
+%!error poissinv (i, 2)
+%!error poissinv (2, i)
+
--- a/scripts/statistics/distributions/poisspdf.m
+++ b/scripts/statistics/distributions/poisspdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -34,24 +35,51 @@
   if (!isscalar (lambda))
     [retval, x, lambda] = common_size (x, lambda);
     if (retval > 0)
-      error ("poisspdf: X and LAMBDA must be of common size or scalar");
+      error ("poisspdf: X and LAMBDA must be of common size or scalars");
     endif
   endif

-  pdf = zeros (size (x));
-
-  k = find (!(lambda > 0) | isnan (x));
-  if (any (k))
-    pdf(k) = NaN;
+  if (iscomplex (x) || iscomplex (lambda))
+    error ("poisspdf: X and LAMBDA must not be complex");
   endif

-  k = find ((x >= 0) & (x < Inf) & (x == round (x)) & (lambda > 0));
-  if (any (k))
-    if (isscalar (lambda))
-      pdf(k) = exp (x(k) .* log (lambda) - lambda - gammaln (x(k) + 1));
-    else
-      pdf(k) = exp (x(k) .* log (lambda(k)) - lambda(k) - gammaln (x(k) + 1));
-    endif
+  if (isa (x, "single") || isa (lambda, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
+  endif
+
+  k = isnan (x) | !(lambda > 0);
+  pdf(k) = NaN;
+
+  k = (x >= 0) & (x < Inf) & (x == fix (x)) & (lambda > 0);
+  if (isscalar (lambda))
+    pdf(k) = exp (x(k) * log (lambda) - lambda - gammaln (x(k) + 1));
+  else
+    pdf(k) = exp (x(k) .* log (lambda(k)) - lambda(k) - gammaln (x(k) + 1));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 2 Inf];
+%! y = [0, exp(-1)*[1 1 0.5], 0];
+%!assert(poisspdf (x, ones(1,5)), y, eps);
+%!assert(poisspdf (x, 1), y, eps);
+%!assert(poisspdf (x, [1 0 NaN 1 1]), [y(1) NaN NaN y(4:5)], eps);
+%!assert(poisspdf ([x, NaN], 1), [y, NaN], eps);
+
+%% Test class of input preserved
+%!assert(poisspdf (single([x, NaN]), 1), single([y, NaN]), eps("single"));
+%!assert(poisspdf ([x, NaN], single(1)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error poisspdf ()
+%!error poisspdf (1)
+%!error poisspdf (1,2,3)
+%!error poisspdf (ones(3),ones(2))
+%!error poisspdf (ones(2),ones(3))
+%!error poisspdf (i, 2)
+%!error poisspdf (2, i)
+
--- a/scripts/statistics/distributions/poissrnd.m
+++ b/scripts/statistics/distributions/poissrnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,73 +18,103 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} poissrnd (@var{lambda}, @var{r}, @var{c})
-## Return an @var{r} by @var{c} matrix of random samples from the
-## Poisson distribution with parameter @var{lambda}, which must be a
-## scalar or of size @var{r} by @var{c}.
+## @deftypefn  {Function File} {} poissrnd (@var{lambda})
+## @deftypefnx {Function File} {} poissrnd (@var{lambda}, @var{r})
+## @deftypefnx {Function File} {} poissrnd (@var{lambda}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} poissrnd (@var{lambda}, [@var{sz}])
+## Return a matrix of random samples from the Poisson distribution with
+## parameter @var{lambda}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the size of @var{lambda}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the size of
+## @var{lambda}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the Poisson distribution

-function rnd = poissrnd (lambda, r, c)
-
-  if (nargin == 3)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("poissrnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("poissrnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+function rnd = poissrnd (lambda, varargin)

-    if (any (size (lambda) != 1)
-        && ((length (size (lambda)) != length (sz)) || any (size (lambda) != sz)))
-      error ("poissrnd: LAMBDA must be scalar or of size [R, C]");
-    endif
-  elseif (nargin == 2)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("poissrnd: R must be a positive integer or vector");
-    endif
-
-    if (any (size (lambda) != 1)
-        && ((length (size (lambda)) != length (sz)) || any (size (lambda) != sz)))
-      error ("poissrnd: LAMBDA must be scalar or of size sz");
-    endif
-  elseif (nargin == 1)
-    sz = size (lambda);
-  else
+  if (nargin < 1)
     print_usage ();
   endif

-  if (isscalar (lambda))
+  if (nargin == 1)
+    sz = size (lambda);
+  elseif (nargin == 2)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("poissrnd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 2)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("poissrnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif

-    if (!(lambda >= 0) || !(lambda < Inf))
-      rnd = NaN (sz);
-    elseif (lambda > 0 && lambda < Inf)
-      rnd = randp(lambda, sz);
+  if (!isscalar (lambda) && !isequal (size (lambda), sz))
+    error ("poissrnd: LAMBDA must be scalar or of size SZ");
+  endif
+
+  if (iscomplex (lambda))
+    error ("poissrnd: LAMBDA must not be complex");
+  endif
+
+  if (isa (lambda, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif
+
+  if (isscalar (lambda))
+    if (lambda > 0 && lambda < Inf)
+      rnd = randp (lambda, sz);
+      if (strcmp (cls, "single"))
+        rnd = single (rnd);
+      endif
     else
-      rnd = zeros (sz);
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = zeros (sz);
+    rnd = NaN (sz, cls);

-    k = find (!(lambda >= 0) | !(lambda < Inf));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
-
-    k = find ((lambda > 0) & (lambda < Inf));
-    if (any (k))
-      rnd(k) = randp(lambda(k), size(k));
-    endif
+    k = (lambda > 0) & (lambda < Inf);
+    rnd(k) = randp (lambda(k));
   endif

 endfunction
+
+
+%!assert(size (poissrnd (2)), [1, 1]);
+%!assert(size (poissrnd (ones(2,1))), [2, 1]);
+%!assert(size (poissrnd (ones(2,2))), [2, 2]);
+%!assert(size (poissrnd (1, 3)), [3, 3]);
+%!assert(size (poissrnd (1, [4 1])), [4, 1]);
+%!assert(size (poissrnd (1, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (poissrnd (2)), "double");
+%!assert(class (poissrnd (single(2))), "single");
+%!assert(class (poissrnd (single([2 2]))), "single");
+
+%% Test input validation
+%!error poissrnd ()
+%!error poissrnd (1, -1)
+%!error poissrnd (1, ones(2))
+%!error poissrnd (1, 2, ones(2))
+%!error poissrnd (i)
+%!error poissrnd (1, 2, -1)
+%!error poissrnd (1, [2 -1 2])
+%!error poissrnd (ones(2,2), 3)
+%!error poissrnd (ones(2,2), [3, 2])
+%!error poissrnd (ones(2,2), 2, 3)
+
--- a/scripts/statistics/distributions/stdnormal_cdf.m
+++ b/scripts/statistics/distributions/stdnormal_cdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,8 +19,9 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} stdnormal_cdf (@var{x})
-## For each component of @var{x}, compute the CDF of the standard normal
-## distribution at @var{x}.
+## For each element of @var{x}, compute the cumulative distribution
+## function (CDF) at @var{x} of the standard normal distribution
+## (mean = 0, standard deviation = 1).
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -31,9 +33,8 @@
     print_usage ();
   endif

-  sz = size (x);
-  if (numel(x) == 0)
-    error ("stdnormal_cdf: X must not be empty");
+  if (iscomplex (x))
+    error ("stdnormal_cdf: X must not be complex");
   endif

   cdf = erfc (x / (-sqrt(2))) / 2;
@@ -41,5 +42,16 @@
 endfunction


+%!shared x,y
+%! x = [-Inf 0 1 Inf];
+%! y = [0, 0.5, 1/2*(1+erf(1/sqrt(2))), 1];
+%!assert(stdnormal_cdf ([x, NaN]), [y, NaN]);

+%% Test class of input preserved
+%!assert(stdnormal_cdf (single([x, NaN])), single([y, NaN]), eps("single"));

+%% Test input validation
+%!error stdnormal_cdf ()
+%!error stdnormal_cdf (1,2)
+%!error stdnormal_cdf (i)
+
--- a/scripts/statistics/distributions/stdnormal_inv.m
+++ b/scripts/statistics/distributions/stdnormal_inv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,8 +19,9 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} stdnormal_inv (@var{x})
-## For each component of @var{x}, compute the quantile (the
-## inverse of the CDF) at @var{x} of the standard normal distribution.
+## For each element of @var{x}, compute the quantile (the
+## inverse of the CDF) at @var{x} of the standard normal distribution
+## (mean = 0, standard deviation = 1).
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
@@ -31,6 +33,25 @@
     print_usage ();
   endif

+  if (iscomplex (x))
+    error ("stdnormal_inv: X must not be complex");
+  endif
+
   inv = sqrt (2) * erfinv (2 * x - 1);

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(stdnormal_inv (x), [NaN -Inf 0 Inf NaN]);
+
+%% Test class of input preserved
+%!assert(stdnormal_inv ([x, NaN]), [NaN -Inf 0 Inf NaN NaN]);
+%!assert(stdnormal_inv (single([x, NaN])), single([NaN -Inf 0 Inf NaN NaN]));
+
+%% Test input validation
+%!error stdnormal_inv ()
+%!error stdnormal_inv (1,2)
+%!error stdnormal_inv (i)
+
--- a/scripts/statistics/distributions/stdnormal_pdf.m
+++ b/scripts/statistics/distributions/stdnormal_pdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -19,7 +20,8 @@
 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} stdnormal_pdf (@var{x})
 ## For each element of @var{x}, compute the probability density function
-## (PDF) of the standard normal distribution at @var{x}.
+## (PDF) at @var{x} of the standard normal distribution (mean = 0,
+## standard deviation = 1).
 ## @end deftypefn

 ## Author: TT <Teresa.Twaroch@ci.tuwien.ac.at>
@@ -31,17 +33,25 @@
     print_usage ();
   endif

-  sz = size(x);
-  pdf = zeros (sz);
-
-  k = find (isnan (x));
-  if (any (k))
-    pdf(k) = NaN;
+  if (iscomplex (x))
+    error ("stdnormal_pdf: X must not be complex");
   endif

-  k = find (!isinf (x));
-  if (any (k))
-    pdf (k) = (2 * pi)^(- 1/2) * exp (- x(k) .^ 2 / 2);
-  endif
+  pdf = (2 * pi)^(- 1/2) * exp (- x .^ 2 / 2);

 endfunction
+
+
+%!shared x,y
+%! x = [-Inf 0 1 Inf];
+%! y = 1/sqrt(2*pi)*exp (-x.^2/2);
+%!assert(stdnormal_pdf ([x, NaN]), [y, NaN], eps);
+
+%% Test class of input preserved
+%!assert(stdnormal_pdf (single([x, NaN])), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error stdnormal_pdf ()
+%!error stdnormal_pdf (1,2)
+%!error stdnormal_pdf (i)
+
--- a/scripts/statistics/distributions/stdnormal_rnd.m
+++ b/scripts/statistics/distributions/stdnormal_rnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,39 +18,57 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} stdnormal_rnd (@var{r}, @var{c})
-## @deftypefnx {Function File} {} stdnormal_rnd (@var{sz})
-## Return an @var{r} by @var{c} or @code{size (@var{sz})} matrix of
-## random numbers from the standard normal distribution.
+## @deftypefn  {Function File} {} stdnormal_rnd (@var{r})
+## @deftypefnx {Function File} {} stdnormal_rnd (@var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} stdnormal_rnd ([@var{sz}])
+## Return a matrix of random samples from the standard normal distribution
+## (mean = 0, standard deviation = 1).
+##
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the standard normal distribution

-function rnd = stdnormal_rnd (r, c)
+function rnd = stdnormal_rnd (varargin)

-  if (nargin != 1 && nargin != 2)
+  if (nargin < 1)
     print_usage ();
   endif

-  if (nargin == 2)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("stdnormal_rnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("stdnormal_rnd: C must be a positive integer");
+  if (nargin == 1)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("stdnormal_rnd: dimension vector must be row vector of non-negative integers");
     endif
-    sz = [r, c];
-  else
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("stdnormal_rnd: R must be a positive integer or vector");
+  elseif (nargin > 1)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("stdnormal_rnd: dimensions must be non-negative integers");
     endif
+    sz = [varargin{:}];
   endif

   rnd = randn (sz);

 endfunction
+
+
+%!assert(size (stdnormal_rnd (3)), [3, 3]);
+%!assert(size (stdnormal_rnd ([4 1])), [4, 1]);
+%!assert(size (stdnormal_rnd (4,1)), [4, 1]);
+
+%% Test input validation
+%!error stdnormal_rnd ()
+%!error stdnormal_rnd (-1)
+%!error stdnormal_rnd (ones(2))
+%!error stdnormal_rnd ([2 -1 2])
+%!error stdnormal_rnd (1, ones(2))
+%!error stdnormal_rnd (1, -1)
+
--- a/scripts/statistics/distributions/tcdf.m
+++ b/scripts/statistics/distributions/tcdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -35,33 +36,59 @@
   if (!isscalar (n))
     [retval, x, n] = common_size (x, n);
     if (retval > 0)
-      error ("tcdf: X and N must be of common size or scalar");
+      error ("tcdf: X and N must be of common size or scalars");
     endif
   endif

-  cdf = zeros (size (x));
+  if (iscomplex (x) || iscomplex (n))
+    error ("tcdf: X and N must not be complex");
+  endif

-  k = find (isnan (x) | !(n > 0));
-  if (any (k))
-    cdf(k) = NaN;
+  if (isa (x, "single") || isa (n, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x == Inf) & (n > 0));
-  if (any (k))
-    cdf(k) = 1;
+  k = !isinf (x) & (n > 0);
+  if (isscalar (n))
+    cdf(k) = betainc (1 ./ (1 + x(k) .^ 2 / n), n/2, 1/2) / 2;
+  else
+    cdf(k) = betainc (1 ./ (1 + x(k) .^ 2 ./ n(k)), n(k)/2, 1/2) / 2;
+  endif
+  k &= (x > 0);
+  if (any (k(:)))
+    cdf(k) = 1 - cdf(k);
   endif

-  k = find ((x > -Inf) & (x < Inf) & (n > 0));
-  if (any (k))
-    if (isscalar (n))
-      cdf(k) = betainc (1 ./ (1 + x(k) .^ 2 ./ n), n / 2, 1 / 2) / 2;
-    else
-      cdf(k) = betainc (1 ./ (1 + x(k) .^ 2 ./ n(k)), n(k) / 2, 1 / 2) / 2;
-    endif
-    ind = find (x(k) > 0);
-    if (any (ind))
-      cdf(k(ind)) = 1 - cdf(k(ind));
-    endif
-  endif
+  k = isnan (x) | !(n > 0);
+  cdf(k) = NaN;
+
+  k = (x == Inf) & (n > 0);
+  cdf(k) = 1;

 endfunction
+
+
+%!shared x,y
+%! x = [-Inf 0 1 Inf];
+%! y = [0 1/2 3/4 1];
+%!assert(tcdf (x, ones(1,4)), y, eps);
+%!assert(tcdf (x, 1), y, eps);
+%!assert(tcdf (x, [0 1 NaN 1]), [NaN 1/2 NaN 1], eps);
+%!assert(tcdf ([x(1:2) NaN x(4)], 1), [y(1:2) NaN y(4)], eps);
+
+%% Test class of input preserved
+%!assert(tcdf ([x, NaN], 1), [y, NaN], eps);
+%!assert(tcdf (single([x, NaN]), 1), single([y, NaN]), eps("single"));
+%!assert(tcdf ([x, NaN], single(1)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error tcdf ()
+%!error tcdf (1)
+%!error tcdf (1,2,3)
+%!error tcdf (ones(3),ones(2))
+%!error tcdf (ones(2),ones(3))
+%!error tcdf (i, 2)
+%!error tcdf (2, i)
+
--- a/scripts/statistics/distributions/tinv.m
+++ b/scripts/statistics/distributions/tinv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -18,11 +19,10 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} tinv (@var{x}, @var{n})
-## For each probability value @var{x}, compute the inverse of the
-## cumulative distribution function (CDF) of the t (Student)
-## distribution with degrees of freedom @var{n}.  This function is
-## analogous to looking in a table for the t-value of a single-tailed
-## distribution.
+## For each element of @var{x}, compute the quantile (the inverse of
+## the CDF) at @var{x} of the t (Student) distribution with @var{n}
+## degrees of freedom.  This function is analogous to looking in a table
+## for the t-value of a single-tailed distribution.
 ## @end deftypefn

 ## For very large n, the "correct" formula does not really work well,
@@ -41,44 +41,68 @@
   if (!isscalar (n))
     [retval, x, n] = common_size (x, n);
     if (retval > 0)
-      error ("tinv: X and N must be of common size or scalar");
+      error ("tinv: X and N must be of common size or scalars");
     endif
   endif

-  inv = zeros (size (x));
-
-  k = find ((x < 0) | (x > 1) | isnan (x) | !(n > 0));
-  if (any (k))
-    inv(k) = NaN;
+  if (iscomplex (x) || iscomplex (n))
+    error ("tinv: X and N must not be complex");
   endif

-  k = find ((x == 0) & (n > 0));
-  if (any (k))
-    inv(k) = -Inf;
-  endif
-
-  k = find ((x == 1) & (n > 0));
-  if (any (k))
-    inv(k) = Inf;
+  if (isa (x, "single") || isa (n, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  k = find ((x > 0) & (x < 1) & (n > 0) & (n < 10000));
-  if (any (k))
-    if (isscalar (n))
-      inv(k) = (sign (x(k) - 1/2)
-                .* sqrt (n .* (1 ./ betainv (2*min (x(k), 1 - x(k)),
-                                                 n/2, 1/2) - 1)));
-    else
+  k = (x == 0) & (n > 0);
+  inv(k) = -Inf;
+
+  k = (x == 1) & (n > 0);
+  inv(k) = Inf;
+
+  if (isscalar (n))
+    k = (x > 0) & (x < 1);
+    if ((n > 0) && (n < 10000))
       inv(k) = (sign (x(k) - 1/2)
-                .* sqrt (n(k) .* (1 ./ betainv (2*min (x(k), 1 - x(k)),
-                                                 n(k)/2, 1/2) - 1)));
+                .* sqrt (n * (1 ./ betainv (2*min (x(k), 1 - x(k)),
+                                            n/2, 1/2) - 1)));
+    elseif (n >= 10000)
+      ## For large n, use the quantiles of the standard normal
+      inv(k) = stdnormal_inv (x(k));
     endif
-  endif
+  else
+    k = (x > 0) & (x < 1) & (n > 0) & (n < 10000);
+    inv(k) = (sign (x(k) - 1/2)
+              .* sqrt (n(k) .* (1 ./ betainv (2*min (x(k), 1 - x(k)),
+                                              n(k)/2, 1/2) - 1)));

-  ## For large n, use the quantiles of the standard normal
-  k = find ((x > 0) & (x < 1) & (n >= 10000));
-  if (any (k))
+    ## For large n, use the quantiles of the standard normal
+    k = (x > 0) & (x < 1) & (n >= 10000);
     inv(k) = stdnormal_inv (x(k));
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(tinv (x, ones(1,5)), [NaN -Inf 0 Inf NaN]);
+%!assert(tinv (x, 1), [NaN -Inf 0 Inf NaN], eps);
+%!assert(tinv (x, [1 0 NaN 1 1]), [NaN NaN NaN Inf NaN], eps);
+%!assert(tinv ([x(1:2) NaN x(4:5)], 1), [NaN -Inf NaN Inf NaN]);
+
+%% Test class of input preserved
+%!assert(tinv ([x, NaN], 1), [NaN -Inf 0 Inf NaN NaN], eps);
+%!assert(tinv (single([x, NaN]), 1), single([NaN -Inf 0 Inf NaN NaN]), eps("single"));
+%!assert(tinv ([x, NaN], single(1)), single([NaN -Inf 0 Inf NaN NaN]), eps("single"));
+
+%% Test input validation
+%!error tinv ()
+%!error tinv (1)
+%!error tinv (1,2,3)
+%!error tinv (ones(3),ones(2))
+%!error tinv (ones(2),ones(3))
+%!error tinv (i, 2)
+%!error tinv (2, i)
+
--- a/scripts/statistics/distributions/tpdf.m
+++ b/scripts/statistics/distributions/tpdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -35,26 +36,58 @@
   if (!isscalar (n))
     [retval, x, n] = common_size (x, n);
     if (retval > 0)
-      error ("tpdf: X and N must be of common size or scalar");
+      error ("tpdf: X and N must be of common size or scalars");
     endif
   endif

-  pdf = zeros (size (x));
+  if (iscomplex (x) || iscomplex (n))
+    error ("tpdf: X and N must not be complex");
+  endif

-  k = find (isnan (x) | !(n > 0) | !(n < Inf));
-  if (any (k))
-    pdf(k) = NaN;
+  if (isa (x, "single") || isa (n, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
   endif

-  k = find (!isinf (x) & !isnan (x) & (n > 0) & (n < Inf));
-  if (any (k))
-    if (isscalar (n))
-      pdf(k) = (exp (- (n + 1) .* log (1 + x(k) .^ 2 ./ n)/2)
-                / (sqrt (n) * beta (n/2, 1/2)));
-    else
-      pdf(k) = (exp (- (n(k) + 1) .* log (1 + x(k) .^ 2 ./ n(k))/2)
-                ./ (sqrt (n(k)) .* beta (n(k)/2, 1/2)));
-    endif
+  k = isnan (x) | !(n > 0) | !(n < Inf);
+  pdf(k) = NaN;
+
+  k = !isinf (x) & !isnan (x) & (n > 0) & (n < Inf);
+  if (isscalar (n))
+    pdf(k) = (exp (- (n + 1) * log (1 + x(k) .^ 2 / n)/2)
+              / (sqrt (n) * beta (n/2, 1/2)));
+  else
+    pdf(k) = (exp (- (n(k) + 1) .* log (1 + x(k) .^ 2 ./ n(k))/2)
+              ./ (sqrt (n(k)) .* beta (n(k)/2, 1/2)));
   endif

 endfunction
+
+
+%!test
+%! x = rand (10,1);
+%! y = 1./(pi * (1 + x.^2));
+%! assert(tpdf (x, 1), y, 5*eps);
+
+%!shared x,y
+%! x = [-Inf 0 0.5 1 Inf];
+%! y = 1./(pi * (1 + x.^2));
+%!assert(tpdf (x, ones(1,5)), y, eps);
+%!assert(tpdf (x, 1), y, eps);
+%!assert(tpdf (x, [0 NaN 1 1 1]), [NaN NaN y(3:5)], eps);
+
+%% Test class of input preserved
+%!assert(tpdf ([x, NaN], 1), [y, NaN], eps);
+%!assert(tpdf (single([x, NaN]), 1), single([y, NaN]), eps("single"));
+%!assert(tpdf ([x, NaN], single(1)), single([y, NaN]), eps("single"));
+
+%% Test input validation
+%!error tpdf ()
+%!error tpdf (1)
+%!error tpdf (1,2,3)
+%!error tpdf (ones(3),ones(2))
+%!error tpdf (ones(2),ones(3))
+%!error tpdf (i, 2)
+%!error tpdf (2, i)
+
--- a/scripts/statistics/distributions/trnd.m
+++ b/scripts/statistics/distributions/trnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,74 +18,100 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} trnd (@var{n}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} trnd (@var{n}, @var{sz})
-## Return an @var{r} by @var{c} matrix of random samples from the t
-## (Student) distribution with @var{n} degrees of freedom.  @var{n} must
-## be a scalar or of size @var{r} by @var{c}.  Or if @var{sz} is a
-## vector create a matrix of size @var{sz}.
+## @deftypefn  {Function File} {} trnd (@var{n})
+## @deftypefnx {Function File} {} trnd (@var{n}, @var{r})
+## @deftypefnx {Function File} {} trnd (@var{n}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} trnd (@var{n}, [@var{sz}])
+## Return a matrix of random samples from the t (Student) distribution with
+## @var{n} degrees of freedom.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the size of @var{n}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the size of
+## @var{n}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the t distribution

-function rnd = trnd (n, r, c)
-
-  if (nargin == 3)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("trnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("trnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+function rnd = trnd (n, varargin)

-    if (any (size (n) != 1)
-        && ((length (size (n)) != length (sz)) || any (size (n) != sz)))
-      error ("trnd: N must be scalar or of size SZ");
-    endif
-  elseif (nargin == 2)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("trnd: R must be a positive integer or vector");
-    endif
-
-    if (any (size (n) != 1)
-        && ((length (size (n)) != length (sz)) || any (size (n) != sz)))
-      error ("trnd: N must be scalar or of size SZ");
-    endif
-  elseif (nargin == 1)
-    sz = size (n);
-  else
+  if (nargin < 1)
     print_usage ();
   endif

+  if (nargin == 1)
+    sz = size (n);
+  elseif (nargin == 2)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
+    else
+      error ("trnd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 2)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("trnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif
+
+  if (!isscalar (n) && !isequal (size (n), sz))
+    error ("trnd: N must be scalar or of size SZ");
+  endif
+
+  if (iscomplex (n))
+    error ("trnd: N must not be complex");
+  endif
+
+  if (isa (n, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif
+
   if (isscalar (n))
-    if (!(n > 0) || !(n < Inf))
-      rnd = NaN (sz);
-    elseif ((n > 0) && (n < Inf))
-      rnd = randn(sz) ./ sqrt(2*randg(n/2,sz)./n);
+    if ((n > 0) && (n < Inf))
+      rnd = randn (sz) ./ sqrt (2*randg (n/2, sz) / n);
     else
-      rnd = zeros (size (n));
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = zeros (size (n));
+    rnd = NaN (sz, cls);

-    k = find (!(n > 0) | !(n < Inf));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
-
-    k = find ((n > 0) & (n < Inf));
-    if (any (k))
-      rnd(k) = randn(size(k)) ./ sqrt(2*randg(n(k)/2,size(k))./n(k));
-    endif
+    k = (n > 0) & (n < Inf);
+    rnd(k) = randn (sum (k(:)), 1) ./ sqrt (2*randg (n(k)/2) ./ n(k))(:);
   endif

 endfunction
+
+
+%!assert(size (trnd (2)), [1, 1]);
+%!assert(size (trnd (ones(2,1))), [2, 1]);
+%!assert(size (trnd (ones(2,2))), [2, 2]);
+%!assert(size (trnd (1, 3)), [3, 3]);
+%!assert(size (trnd (1, [4 1])), [4, 1]);
+%!assert(size (trnd (1, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (trnd (1)), "double");
+%!assert(class (trnd (single(1))), "single");
+%!assert(class (trnd (single([1 1]))), "single");
+
+%% Test input validation
+%!error trnd ()
+%!error trnd (1, -1)
+%!error trnd (1, ones(2))
+%!error trnd (i)
+%!error trnd (1, [2 -1 2])
+%!error trnd (1, 2, ones(2))
+%!error trnd (1, 2, -1)
+%!error trnd (ones(2,2), 3)
+%!error trnd (ones(2,2), [3, 2])
+%!error trnd (ones(2,2), 2, 3)
+
--- a/scripts/statistics/distributions/unidcdf.m
+++ b/scripts/statistics/distributions/unidcdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 2007-2011 David Bateman
 ##
 ## This file is part of Octave.
@@ -17,26 +18,72 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} unidcdf (@var{x}, @var{v})
+## @deftypefn {Function File} {} unidcdf (@var{x}, @var{n})
 ## For each element of @var{x}, compute the cumulative distribution
-## function (CDF) at @var{x} of a discrete uniform distribution which
-## assumes the values in @var{v} with equal probability.
-## If @var{v} is a scalar then @code{1/@var{v}} is the probability of a
-## single element.
+## function (CDF) at @var{x} of a discrete uniform distribution which assumes
+## the integer values 1--@var{n} with equal probability.
 ## @end deftypefn

-function cdf = unidcdf (x, v)
+function cdf = unidcdf (x, n)

   if (nargin != 2)
     print_usage ();
   endif

-  if (isscalar(v))
-    v = [1:v].';
+  if (! isscalar (n))
+    [retval, x, n] = common_size (x, n);
+    if (retval > 0)
+      error ("unidcdf: X and N must be of common size or scalars");
+    endif
+  endif
+
+  if (iscomplex (x) || iscomplex (n))
+    error ("unidcdf: X and N must not be complex");
+  endif
+
+  if (isa (x, "single") || isa (n, "single"))
+    cdf = zeros (size (x), "single");
   else
-    v = v(:);
+    cdf = zeros (size (x));
+  endif
+
+  knan = isnan (x) | ! (n > 0 & n == fix (n));
+  if (any (knan(:)))
+    cdf(knan) = NaN;
   endif

-  cdf = discrete_cdf (x, v, ones(size(v)));
+  k = (x >= n) & !knan;
+  cdf(k) = 1;
+
+  k = (x >= 1) & (x < n) & !knan;
+  if (isscalar (n))
+    cdf(k) = floor (x(k)) / n;
+  else
+    cdf(k) = floor (x(k)) ./ n(k);
+  endif

 endfunction
+
+
+%!shared x,y
+%! x = [0 1 2.5 10 11];
+%! y = [0, 0.1 0.2 1.0 1.0];
+%!assert(unidcdf (x, 10*ones(1,5)), y);
+%!assert(unidcdf (x, 10), y);
+%!assert(unidcdf (x, 10*[0 1 NaN 1 1]), [NaN 0.1 NaN y(4:5)]);
+%!assert(unidcdf ([x(1:2) NaN Inf x(5)], 10), [y(1:2) NaN 1 y(5)]);
+
+%% Test class of input preserved
+%!assert(unidcdf ([x, NaN], 10), [y, NaN]);
+%!assert(unidcdf (single([x, NaN]), 10), single([y, NaN]));
+%!assert(unidcdf ([x, NaN], single(10)), single([y, NaN]));
+
+%% Test input validation
+%!error unidcdf ()
+%!error unidcdf (1)
+%!error unidcdf (1,2,3)
+%!error unidcdf (ones(3),ones(2))
+%!error unidcdf (ones(2),ones(3))
+%!error unidcdf (i, 2)
+%!error unidcdf (2, i)
+
--- a/scripts/statistics/distributions/unidinv.m
+++ b/scripts/statistics/distributions/unidinv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 2007-2011 David Bateman
 ##
 ## This file is part of Octave.
@@ -17,25 +18,64 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} unidinv (@var{x}, @var{v})
-## For each component of @var{x}, compute the quantile (the inverse of
-## the CDF) at @var{x} of the discrete uniform distribution which assumes the
-## values in @var{v} with equal probability.
-## If @var{v} is a scalar then @code{1/@var{v}} is the probability of a
-## single element.
+## @deftypefn {Function File} {} unidinv (@var{x}, @var{n})
+## For each element of @var{x}, compute the quantile (the inverse of
+## the CDF) at @var{x} of the discrete uniform distribution which assumes
+## the integer values 1--@var{n} with equal probability.
 ## @end deftypefn

-function inv = unidinv (x, v)
+function inv = unidinv (x, n)

   if (nargin != 2)
     print_usage ();
   endif

-  if (isscalar(v))
-    v = [1:v].';
+  if (! isscalar (n))
+    [retval, x, n] = common_size (x, n);
+    if (retval > 0)
+      error ("unidcdf: X and N must be of common size or scalars");
+    endif
+  endif
+
+  if (iscomplex (x) || iscomplex (n))
+    error ("unidinv: X and N must not be complex");
+  endif
+
+  if (isa (x, "single") || isa (n, "single"))
+    inv = NaN (size (x), "single");
   else
-    v = v(:);
+    inv = NaN (size (x));
+  endif
+
+  ## For Matlab compatibility, unidinv(0) = NaN
+  k = (x > 0) & (x <= 1) & (n > 0 & n == fix (n));
+  if (isscalar (n))
+    inv(k) = floor (x(k) * n);
+  else
+    inv(k) = floor (x(k) .* n(k));
   endif

-  inv = discrete_inv (x, v, ones(size(v)));
 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(unidinv (x, 10*ones(1,5)), [NaN NaN 5 10 NaN], eps);
+%!assert(unidinv (x, 10), [NaN NaN 5 10 NaN], eps);
+%!assert(unidinv (x, 10*[0 1 NaN 1 1]), [NaN NaN NaN 10 NaN], eps);
+%!assert(unidinv ([x(1:2) NaN x(4:5)], 10), [NaN NaN NaN 10 NaN], eps);
+
+%% Test class of input preserved
+%!assert(unidinv ([x, NaN], 10), [NaN NaN 5 10 NaN NaN], eps);
+%!assert(unidinv (single([x, NaN]), 10), single([NaN NaN 5 10 NaN NaN]), eps);
+%!assert(unidinv ([x, NaN], single(10)), single([NaN NaN 5 10 NaN NaN]), eps);
+
+%% Test input validation
+%!error unidinv ()
+%!error unidinv (1)
+%!error unidinv (1,2,3)
+%!error unidinv (ones(3),ones(2))
+%!error unidinv (ones(2),ones(3))
+%!error unidinv (i, 2)
+%!error unidinv (2, i)
+
--- a/scripts/statistics/distributions/unidpdf.m
+++ b/scripts/statistics/distributions/unidpdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 2007-2011 David Bateman
 ##
 ## This file is part of Octave.
@@ -17,25 +18,70 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} unidpdf (@var{x}, @var{v})
+## @deftypefn {Function File} {} unidpdf (@var{x}, @var{n})
 ## For each element of @var{x}, compute the probability density function
 ## (PDF) at @var{x} of a discrete uniform distribution which assumes
-## the values in @var{v} with equal probability.
-## If @var{v} is a scalar then @code{1/@var{v}} is the probability of a
-## single element.
+## the integer values 1--@var{n} with equal probability.
+##
+## Warning: The underlying implementation uses the double class and
+## will only be accurate for @var{n} @leq{} @code{bitmax}
+## (@w{@math{2^{53} - 1}} on IEEE-754 compatible systems).
 ## @end deftypefn

-function pdf = unidpdf (x, v)
+function pdf = unidpdf (x, n)

   if (nargin != 2)
     print_usage ();
   endif

-  if (isscalar(v))
-    v = [1:v].';
+  if (! isscalar (n))
+    [retval, x, n] = common_size (x, n);
+    if (retval > 0)
+      error ("unidpdf: X and N must be of common size or scalars");
+    endif
+  endif
+
+  if (iscomplex (x) || iscomplex (n))
+    error ("unidpdf: X and N must not be complex");
+  endif
+
+  if (isa (x, "single") || isa (n, "single"))
+    pdf = zeros (size (x), "single");
   else
-    v = v(:);
+    pdf = zeros (size (x));
   endif

-  pdf = discrete_pdf (x, v, ones(size(v)));
+  k = isnan (x) | ! (n > 0 & n == fix (n));
+  pdf(k) = NaN;
+
+  k = !k & (x >= 1) & (x <= n) & (x == fix (x));
+  if (isscalar (n))
+    pdf(k) = 1 / n;
+  else
+    pdf(k) = 1 ./ n(k);
+  endif
+
 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 1 2 10 11];
+%! y = [0 0 0.1 0.1 0.1 0];
+%!assert(unidpdf (x, 10*ones(1,6)), y);
+%!assert(unidpdf (x, 10), y);
+%!assert(unidpdf (x, 10*[0 NaN 1 1 1 1]), [NaN NaN y(3:6)]);
+%!assert(unidpdf ([x, NaN], 10), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(unidpdf (single([x, NaN]), 10), single([y, NaN]));
+%!assert(unidpdf ([x, NaN], single(10)), single([y, NaN]));
+
+%% Test input validation
+%!error unidpdf ()
+%!error unidpdf (1)
+%!error unidpdf (1,2,3)
+%!error unidpdf (ones(3),ones(2))
+%!error unidpdf (ones(2),ones(3))
+%!error unidpdf (i, 2)
+%!error unidpdf (2, i)
+
--- a/scripts/statistics/distributions/unidrnd.m
+++ b/scripts/statistics/distributions/unidrnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 2005-2011 John W. Eaton
 ##
 ## This file is part of Octave.
@@ -17,44 +18,94 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} unidrnd (@var{mx});
-## @deftypefnx {Function File} {} unidrnd (@var{mx}, @var{v});
-## @deftypefnx {Function File} {} unidrnd (@var{mx}, @var{m}, @var{n}, @dots{});
-## Return random values from a discrete uniform distribution with maximum
-## value(s) given by the integer @var{mx} (which may be a scalar or
-## multi-dimensional array).
+## @deftypefn  {Function File} {} unidrnd (@var{n})
+## @deftypefnx {Function File} {} unidrnd (@var{n}, @var{r})
+## @deftypefnx {Function File} {} unidrnd (@var{n}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} unidrnd (@var{n}, [@var{sz}])
+## Return a matrix of random samples from the discrete uniform distribution
+## which assumes the integer values 1--@var{n} with equal probability.
+## @var{n} may be a scalar or a multi-dimensional array.
 ##
-## If @var{mx} is a scalar, the size of the result is specified by
-## the vector @var{v}, or by the optional arguments @var{m}, @var{n},
-## @dots{}.  Otherwise, the size of the result is the same as the size
-## of @var{mx}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the size of
+## @var{n}.
 ## @end deftypefn

 ## Author: jwe

-function retval = unidrnd (n, varargin)
+function rnd = unidrnd (n, varargin)
+
+  if (nargin < 1)
+    print_usage ();
+  endif
+
   if (nargin == 1)
-    dims = size (n);
+    sz = size (n);
   elseif (nargin == 2)
-    if (rows (varargin{1}) == 1 && columns (varargin{1}) > 1)
-      dims = varargin{1};
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      error ("unidrnd: invalid dimension vector");
+      error ("unidrnd: dimension vector must be row vector of non-negative integers");
     endif
   elseif (nargin > 2)
-    for i = 1:nargin-1
-      if (! isscalar (varargin{i}))
-        error ("unidrnd: expecting scalar dimensions");
-      endif
-    endfor
-    dims = [varargin{:}];
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("unidrnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif
+
+  if (!isscalar (n) && !isequal (size (n), sz))
+    error ("unidrnd: N must be scalar or of size SZ");
+  endif
+
+  if (iscomplex (n))
+    error ("unidrnd: N must not be complex");
+  endif
+
+  if (isa (n, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif
+
+  if (isscalar (n))
+    if (n > 0 && n == fix (n))
+      rnd = ceil (rand (sz) * n);
+    else
+      rnd = NaN (sz, cls);
+    endif
   else
-    print_usage ();
+    rnd = ceil (rand (sz) .* n);
+
+    k = ! (n > 0 & n == fix (n));
+    rnd(k) = NaN;
   endif
-  if (isscalar (n)
-      || (length (size (n)) == length (dims) && all (size (n) == dims)))
-    retval = ceil (rand (dims) .* n);
-  else
-    error ("unidrnd: dimension mismatch");
-  endif
+
 endfunction
+
+
+%!assert(size (unidrnd (2)), [1, 1]);
+%!assert(size (unidrnd (ones(2,1))), [2, 1]);
+%!assert(size (unidrnd (ones(2,2))), [2, 2]);
+%!assert(size (unidrnd (10, [4 1])), [4, 1]);
+%!assert(size (unidrnd (10, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (unidrnd (2)), "double");
+%!assert(class (unidrnd (single(2))), "single");
+%!assert(class (unidrnd (single([2 2]))), "single");
+
+%% Test input validation
+%!error unidrnd ()
+%!error unidrnd (10, [1;2;3])
+%!error unidrnd (10, 2, ones(2))
+%!error unidrnd (10*ones(2), 2, 1)
+%!error unidrnd (i)
+
--- a/scripts/statistics/distributions/unifcdf.m
+++ b/scripts/statistics/distributions/unifcdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,9 +18,11 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} unifcdf (@var{x}, @var{a}, @var{b})
-## Return the CDF at @var{x} of the uniform distribution on [@var{a},
-## @var{b}], i.e., PROB (uniform (@var{a}, @var{b}) @leq{} x).
+## @deftypefn  {Function File} {} unifcdf (@var{x})
+## @deftypefnx {Function File} {} unifcdf (@var{x}, @var{a}, @var{b})
+## For each element of @var{x}, compute the cumulative distribution
+## function (CDF) at @var{x} of the uniform distribution on the interval
+## [@var{a}, @var{b}].
 ##
 ## Default values are @var{a} = 0, @var{b} = 1.
 ## @end deftypefn
@@ -27,44 +30,69 @@
 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: CDF of the uniform distribution

-function cdf = unifcdf (x, a, b)
+function cdf = unifcdf (x, a = 0, b = 1)

   if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    a = 0;
-    b = 1;
-  endif
-
-  if (!isscalar (a) || !isscalar(b))
+  if (!isscalar (a) || !isscalar (b))
     [retval, x, a, b] = common_size (x, a, b);
     if (retval > 0)
-      error ("unifcdf: X, A and B must be of common size or scalar");
+      error ("unifcdf: X, A, and B must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  cdf = zeros (sz);
+  if (iscomplex (x) || iscomplex (a) || iscomplex (b))
+    error ("unifcdf: X, A, and B must not be complex");
+  endif

-  k = find (isnan (x) | !(a < b));
-  if (any (k))
-    cdf(k) = NaN;
+  if (isa (x, "single") || isa (a, "single") || isa (b, "single"))
+    cdf = zeros (size (x), "single");
+  else
+    cdf = zeros (size (x));
   endif

-  k = find ((x >= b) & (a < b));
-  if (any (k))
-    cdf(k) = 1;
-  endif
+  k = isnan (x) | !(a < b);
+  cdf(k) = NaN;
+
+  k = (x >= b) & (a < b);
+  cdf(k) = 1;

-  k = find ((x > a) & (x < b));
-  if (any (k))
-    if (isscalar (a) && isscalar(b))
-      cdf(k) = (x(k) < b) .* (x(k) - a) ./ (b - a);
-    else
-      cdf(k) = (x(k) < b(k)) .* (x(k) - a(k)) ./ (b(k) - a(k));
-    endif
+  k = (x > a) & (x < b);
+  if (isscalar (a) && isscalar (b))
+    cdf(k) = (x(k) < b) .* (x(k) - a) / (b - a);
+  else
+    cdf(k) = (x(k) < b(k)) .* (x(k) - a(k)) ./ (b(k) - a(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2] + 1;
+%! y = [0 0 0.5 1 1];
+%!assert(unifcdf (x, ones(1,5), 2*ones(1,5)), y);
+%!assert(unifcdf (x, 1, 2*ones(1,5)), y);
+%!assert(unifcdf (x, ones(1,5), 2), y);
+%!assert(unifcdf (x, [2 1 NaN 1 1], 2), [NaN 0 NaN 1 1]);
+%!assert(unifcdf (x, 1, 2*[0 1 NaN 1 1]), [NaN 0 NaN 1 1]);
+%!assert(unifcdf ([x(1:2) NaN x(4:5)], 1, 2), [y(1:2) NaN y(4:5)]);
+
+%% Test class of input preserved
+%!assert(unifcdf ([x, NaN], 1, 2), [y, NaN]);
+%!assert(unifcdf (single([x, NaN]), 1, 2), single([y, NaN]));
+%!assert(unifcdf ([x, NaN], single(1), 2), single([y, NaN]));
+%!assert(unifcdf ([x, NaN], 1, single(2)), single([y, NaN]));
+
+%% Test input validation
+%!error unifcdf ()
+%!error unifcdf (1,2)
+%!error unifcdf (1,2,3,4)
+%!error unifcdf (ones(3),ones(2),ones(2))
+%!error unifcdf (ones(2),ones(3),ones(2))
+%!error unifcdf (ones(2),ones(2),ones(3))
+%!error unifcdf (i, 2, 2)
+%!error unifcdf (2, i, 2)
+%!error unifcdf (2, 2, i)
+
--- a/scripts/statistics/distributions/unifinv.m
+++ b/scripts/statistics/distributions/unifinv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,9 +18,11 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} unifinv (@var{x}, @var{a}, @var{b})
+## @deftypefn  {Function File} {} unifinv (@var{x})
+## @deftypefnx {Function File} {} unifinv (@var{x}, @var{a}, @var{b})
 ## For each element of @var{x}, compute the quantile (the inverse of the
-## CDF) at @var{x} of the uniform distribution on [@var{a}, @var{b}].
+## CDF) at @var{x} of the uniform distribution on the interval
+## [@var{a}, @var{b}].
 ##
 ## Default values are @var{a} = 0, @var{b} = 1.
 ## @end deftypefn
@@ -27,39 +30,62 @@
 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Quantile function of the uniform distribution

-function inv = unifinv (x, a, b)
+function inv = unifinv (x, a = 0, b = 1)

   if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    a = 0;
-    b = 1;
-  endif
-
-  if (!isscalar (a) || !isscalar(b))
+  if (!isscalar (a) || !isscalar (b))
     [retval, x, a, b] = common_size (x, a, b);
     if (retval > 0)
-      error ("unifinv: X, A and B must be of common size or scalar");
+      error ("unifinv: X, A, and B must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  inv = zeros (sz);
-
-  k = find ((x < 0) | (x > 1) | isnan (x) | !(a < b));
-  if (any (k))
-    inv(k) = NaN;
+  if (iscomplex (x) || iscomplex (a) || iscomplex (b))
+    error ("unifinv: X, A, and B must not be complex");
   endif

-  k = find ((x >= 0) & (x <= 1) & (a < b));
-  if (any (k))
-    if (isscalar (a) && isscalar(b))
-      inv(k) = a + x(k) .* (b - a);
-    else
-      inv(k) = a(k) + x(k) .* (b(k) - a(k));
-    endif
+  if (isa (x, "single") || isa (a, "single") || isa (b, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
+  endif
+
+  k = (x >= 0) & (x <= 1) & (a < b);
+  if (isscalar (a) && isscalar (b))
+    inv(k) = a + x(k) * (b - a);
+  else
+    inv(k) = a(k) + x(k) .* (b(k) - a(k));
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.5 1 2];
+%!assert(unifinv (x, ones(1,5), 2*ones(1,5)), [NaN 1 1.5 2 NaN]);
+%!assert(unifinv (x, 1, 2*ones(1,5)), [NaN 1 1.5 2 NaN]);
+%!assert(unifinv (x, ones(1,5), 2), [NaN 1 1.5 2 NaN]);
+%!assert(unifinv (x, [1 2 NaN 1 1], 2), [NaN NaN NaN 2 NaN]);
+%!assert(unifinv (x, 1, 2*[1 0 NaN 1 1]), [NaN NaN NaN 2 NaN]);
+%!assert(unifinv ([x(1:2) NaN x(4:5)], 1, 2), [NaN 1 NaN 2 NaN]);
+
+%% Test class of input preserved
+%!assert(unifinv ([x, NaN], 1, 2), [NaN 1 1.5 2 NaN NaN]);
+%!assert(unifinv (single([x, NaN]), 1, 2), single([NaN 1 1.5 2 NaN NaN]));
+%!assert(unifinv ([x, NaN], single(1), 2), single([NaN 1 1.5 2 NaN NaN]));
+%!assert(unifinv ([x, NaN], 1, single(2)), single([NaN 1 1.5 2 NaN NaN]));
+
+%% Test input validation
+%!error unifinv ()
+%!error unifinv (1,2)
+%!error unifinv (1,2,3,4)
+%!error unifinv (ones(3),ones(2),ones(2))
+%!error unifinv (ones(2),ones(3),ones(2))
+%!error unifinv (ones(2),ones(2),ones(3))
+%!error unifinv (i, 2, 2)
+%!error unifinv (2, i, 2)
+%!error unifinv (2, 2, i)
+
--- a/scripts/statistics/distributions/unifpdf.m
+++ b/scripts/statistics/distributions/unifpdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,9 +18,10 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} unifpdf (@var{x}, @var{a}, @var{b})
-## For each element of @var{x}, compute the PDF at @var{x} of the uniform
-## distribution on [@var{a}, @var{b}].
+## @deftypefn  {Function File} {} unifpdf (@var{x})
+## @deftypefnx {Function File} {} unifpdf (@var{x}, @var{a}, @var{b})
+## For each element of @var{x}, compute the probability density function (PDF)
+## at @var{x} of the uniform distribution on the interval [@var{a}, @var{b}].
 ##
 ## Default values are @var{a} = 0, @var{b} = 1.
 ## @end deftypefn
@@ -27,39 +29,65 @@
 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: PDF of the uniform distribution

-function pdf = unifpdf (x, a, b)
+function pdf = unifpdf (x, a = 0, b = 1)

   if (nargin != 1 && nargin != 3)
     print_usage ();
   endif

-  if (nargin == 1)
-    a = 0;
-    b = 1;
-  endif
-
-  if (!isscalar (a) || !isscalar(b))
+  if (!isscalar (a) || !isscalar (b))
     [retval, x, a, b] = common_size (x, a, b);
     if (retval > 0)
-      error ("unifpdf: X, A and B must be of common size or scalars");
+      error ("unifpdf: X, A, and B must be of common size or scalars");
     endif
   endif

-  sz = size (x);
-  pdf = zeros (sz);
-
-  k = find (isnan (x) | !(a < b));
-  if (any (k))
-    pdf(k) = NaN;
+  if (iscomplex (x) || iscomplex (a) || iscomplex (b))
+    error ("unifpdf: X, A, and B must not be complex");
   endif

-  k = find ((x >= a) & (x <= b));
-  if (any (k))
-    if (isscalar (a) && isscalar(b))
-      pdf(k) = 1 ./ (b - a);
-    else
-      pdf(k) = 1 ./ (b(k) - a(k));
-    endif
+  if (isa (x, "single") || isa (a, "single") || isa (b, "single"))
+    pdf = zeros (size (x), "single");
+  else
+    pdf = zeros (size (x));
+  endif
+
+  k = isnan (x) | !(a < b);
+  pdf(k) = NaN;
+
+  k = (x >= a) & (x <= b) & (a < b);
+  if (isscalar (a) && isscalar (b))
+    pdf(k) = 1 / (b - a);
+  else
+    pdf(k) = 1 ./ (b(k) - a(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 2] + 1;
+%! y = [0 1 1 1 0];
+%!assert(unifpdf (x, ones(1,5), 2*ones(1,5)), y);
+%!assert(unifpdf (x, 1, 2*ones(1,5)), y);
+%!assert(unifpdf (x, ones(1,5), 2), y);
+%!assert(unifpdf (x, [2 NaN 1 1 1], 2), [NaN NaN y(3:5)]);
+%!assert(unifpdf (x, 1, 2*[0 NaN 1 1 1]), [NaN NaN y(3:5)]);
+%!assert(unifpdf ([x, NaN], 1, 2), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(unifpdf (single([x, NaN]), 1, 2), single([y, NaN]));
+%!assert(unifpdf (single([x, NaN]), single(1), 2), single([y, NaN]));
+%!assert(unifpdf ([x, NaN], 1, single(2)), single([y, NaN]));
+
+%% Test input validation
+%!error unifpdf ()
+%!error unifpdf (1,2)
+%!error unifpdf (1,2,3,4)
+%!error unifpdf (ones(3),ones(2),ones(2))
+%!error unifpdf (ones(2),ones(3),ones(2))
+%!error unifpdf (ones(2),ones(2),ones(3))
+%!error unifpdf (i, 2, 2)
+%!error unifpdf (2, i, 2)
+%!error unifpdf (2, 2, i)
+
--- a/scripts/statistics/distributions/unifrnd.m
+++ b/scripts/statistics/distributions/unifrnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,75 +18,115 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} unifrnd (@var{a}, @var{b}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} unifrnd (@var{a}, @var{b}, @var{sz})
-## Return an @var{r} by @var{c} or a @code{size (@var{sz})} matrix of
-## random samples from the uniform distribution on [@var{a}, @var{b}].
-## Both @var{a} and @var{b} must be scalar or of size @var{r} by @var{c}.
+## @deftypefn  {Function File} {} unifrnd (@var{a}, @var{b})
+## @deftypefnx {Function File} {} unifrnd (@var{a}, @var{b}, @var{r})
+## @deftypefnx {Function File} {} unifrnd (@var{a}, @var{b}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} unifrnd (@var{a}, @var{b}, [@var{sz}])
+## Return a matrix of random samples from the uniform distribution on
+## [@var{a}, @var{b}].
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{a} and @var{b}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{a} and @var{b}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the uniform distribution

-function rnd = unifrnd (a, b, r, c)
+function rnd = unifrnd (a, b, varargin)

-  if (nargin > 1)
-    if (!isscalar(a) || !isscalar(b))
-      [retval, a, b] = common_size (a, b);
-      if (retval > 0)
-        error ("unifrnd: A and B must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (a) || !isscalar (b))
+    [retval, a, b] = common_size (a, b);
+    if (retval > 0)
+      error ("unifrnd: A and B must be of common size or scalars");
     endif
   endif

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("unifrnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("unifrnd: C must be a positive integer");
-    endif
-    sz = [r, c];
-
-    if (any (size (a) != 1)
-        && (length (size (a)) != length (sz) || any (size (a) != sz)))
-      error ("unifrnd: A and B must be scalar or of size [R, C]");
-    endif
-  elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
-    else
-      error ("unifrnd: R must be a positive integer or vector");
-    endif
-
-    if (any (size (a) != 1)
-        && (length (size (a)) != length (sz) || any (size (a) != sz)))
-      error ("unifrnd: A and B must be scalar or of size SZ");
-    endif
-  elseif (nargin == 2)
-    sz = size(a);
-  else
-    print_usage ();
+  if (iscomplex (a) || iscomplex (b))
+    error ("unifrnd: A and B must not be complex");
   endif

-  if (isscalar(a) && isscalar(b))
-    if (find (!(-Inf < a) | !(a < b) | !(b < Inf)))
-      rnd = NaN(sz);
+  if (nargin == 2)
+    sz = size (a);
+  elseif (nargin == 3)
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      rnd =  a + (b - a) .* rand (sz);
+      error ("unifrnd: dimension vector must be row vector of non-negative integers");
+    endif
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("unifrnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif
+
+  if (!isscalar (a) && !isequal (size (a), sz))
+    error ("unifrnd: A and B must be scalar or of size SZ");
+  endif
+
+  if (isa (a, "single") || isa (b, "single"))
+    cls = "single";
+  else
+    cls = "double";
+  endif
+
+  if (isscalar (a) && isscalar (b))
+    if ((-Inf < a) && (a < b) && (b < Inf))
+      rnd =  a + (b - a) * rand (sz);
+    else
+      rnd = NaN (sz, cls);
     endif
   else
     rnd =  a + (b - a) .* rand (sz);

-    k = find (!(-Inf < a) | !(a < b) | !(b < Inf));
-    if (any (k))
-      rnd(k) = NaN;
-    endif
+    k = !(-Inf < a) | !(a < b) | !(b < Inf);
+    rnd(k) = NaN;
   endif

 endfunction
+
+
+%!assert(size (unifrnd (1,2)), [1, 1]);
+%!assert(size (unifrnd (ones(2,1), 2)), [2, 1]);
+%!assert(size (unifrnd (ones(2,2), 2)), [2, 2]);
+%!assert(size (unifrnd (1, 2*ones(2,1))), [2, 1]);
+%!assert(size (unifrnd (1, 2*ones(2,2))), [2, 2]);
+%!assert(size (unifrnd (1, 2, 3)), [3, 3]);
+%!assert(size (unifrnd (1, 2, [4 1])), [4, 1]);
+%!assert(size (unifrnd (1, 2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (unifrnd (1, 2)), "double");
+%!assert(class (unifrnd (single(1), 2)), "single");
+%!assert(class (unifrnd (single([1 1]), 2)), "single");
+%!assert(class (unifrnd (1, single(2))), "single");
+%!assert(class (unifrnd (1, single([2 2]))), "single");
+
+%% Test input validation
+%!error unifrnd ()
+%!error unifrnd (1)
+%!error unifrnd (ones(3),ones(2))
+%!error unifrnd (ones(2),ones(3))
+%!error unifrnd (i, 2)
+%!error unifrnd (2, i)
+%!error unifrnd (1,2, -1)
+%!error unifrnd (1,2, ones(2))
+%!error unifrnd (1, 2, [2 -1 2])
+%!error unifrnd (1,2, 1, ones(2))
+%!error unifrnd (1,2, 1, -1)
+%!error unifrnd (ones(2,2), 2, 3)
+%!error unifrnd (ones(2,2), 2, [3, 2])
+%!error unifrnd (ones(2,2), 2, 2, 3)
+
--- a/scripts/statistics/distributions/wblcdf.m
+++ b/scripts/statistics/distributions/wblcdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,7 +18,9 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} wblcdf (@var{x}, @var{scale}, @var{shape})
+## @deftypefn  {Function File} {} wblcdf (@var{x})
+## @deftypefnx {Function File} {} wblcdf (@var{x}, @var{scale})
+## @deftypefnx {Function File} {} wblcdf (@var{x}, @var{scale}, @var{shape})
 ## Compute the cumulative distribution function (CDF) at @var{x} of the
 ## Weibull distribution with scale parameter @var{scale} and shape
 ## parameter @var{shape}, which is
@@ -28,59 +31,83 @@
 ## @ifnottex
 ##
 ## @example
-## 1 - exp(-(x/scale)^shape)
+## 1 - exp (-(x/scale)^shape)
 ## @end example
 ##
 ## @noindent
 ## for @var{x} @geq{} 0.
+##
+## Default values are @var{scale} = 1, @var{shape} = 1.
 ## @end ifnottex
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: CDF of the Weibull distribution

-function cdf = wblcdf (x, scale, shape)
+function cdf = wblcdf (x, scale = 1, shape = 1)

   if (nargin < 1 || nargin > 3)
     print_usage ();
   endif

-  if (nargin < 3)
-    shape = 1;
-  endif
-
-  if (nargin < 2)
-    scale = 1;
-  endif
-
   if (!isscalar (shape) || !isscalar (scale))
     [retval, x, shape, scale] = common_size (x, shape, scale);
     if (retval > 0)
-      error ("wblcdf: X, SCALE and SHAPE must be of common size or scalar");
+      error ("wblcdf: X, SCALE, and SHAPE must be of common size or scalars");
     endif
   endif

-  cdf = NaN (size (x));
-
-  ok = ((shape > 0) & (shape < Inf) & (scale > 0) & (scale < Inf));
+  if (iscomplex (x) || iscomplex (scale) || iscomplex (shape))
+    error ("wblcdf: X, SCALE, and SHAPE must not be complex");
+  endif

-  k = find ((x <= 0) & ok);
-  if (any (k))
-    cdf(k) = 0;
+  if (isa (x, "single") || isa (scale, "single") || isa (shape, "single"))
+    cdf = NaN (size (x), "single");
+  else
+    cdf = NaN (size (x));
   endif

-  k = find ((x > 0) & (x < Inf) & ok);
-  if (any (k))
-    if (isscalar (shape) && isscalar (scale))
-      cdf(k) = 1 - exp (- (x(k) / scale) .^ shape);
-    else
-      cdf(k) = 1 - exp (- (x(k) ./ scale(k)) .^ shape(k));
-    endif
-  endif
+  ok = (shape > 0) & (shape < Inf) & (scale > 0) & (scale < Inf);
+
+  k = (x <= 0) & ok;
+  cdf(k) = 0;

-  k = find ((x == Inf) & ok);
-  if (any (k))
-    cdf(k) = 1;
+  k = (x == Inf) & ok;
+  cdf(k) = 1;
+
+  k = (x > 0) & (x < Inf) & ok;
+  if (isscalar (shape) && isscalar (scale))
+    cdf(k) = 1 - exp (- (x(k) / scale) .^ shape);
+  else
+    cdf(k) = 1 - exp (- (x(k) ./ scale(k)) .^ shape(k));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 Inf];
+%! y = [0, 1-exp(-x(2:4)), 1];
+%!assert(wblcdf (x, ones(1,5), ones(1,5)), y);
+%!assert(wblcdf (x, 1, ones(1,5)), y);
+%!assert(wblcdf (x, ones(1,5), 1), y);
+%!assert(wblcdf (x, [0 1 NaN Inf 1], 1), [NaN 0 NaN NaN 1]);
+%!assert(wblcdf (x, 1, [0 1 NaN Inf 1]), [NaN 0 NaN NaN 1]);
+%!assert(wblcdf ([x(1:2) NaN x(4:5)], 1, 1), [y(1:2) NaN y(4:5)]);
+
+%% Test class of input preserved
+%!assert(wblcdf ([x, NaN], 1, 1), [y, NaN]);
+%!assert(wblcdf (single([x, NaN]), 1, 1), single([y, NaN]));
+%!assert(wblcdf ([x, NaN], single(1), 1), single([y, NaN]));
+%!assert(wblcdf ([x, NaN], 1, single(1)), single([y, NaN]));
+
+%% Test input validation
+%!error wblcdf ()
+%!error wblcdf (1,2,3,4)
+%!error wblcdf (ones(3),ones(2),ones(2))
+%!error wblcdf (ones(2),ones(3),ones(2))
+%!error wblcdf (ones(2),ones(2),ones(3))
+%!error wblcdf (i, 2, 2)
+%!error wblcdf (2, i, 2)
+%!error wblcdf (2, 2, i)
+
--- a/scripts/statistics/distributions/wblinv.m
+++ b/scripts/statistics/distributions/wblinv.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,57 +18,82 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} wblinv (@var{x}, @var{scale}, @var{shape})
+## @deftypefn  {Function File} {} wblinv (@var{x})
+## @deftypefnx {Function File} {} wblinv (@var{x}, @var{scale})
+## @deftypefnx {Function File} {} wblinv (@var{x}, @var{scale}, @var{shape})
 ## Compute the quantile (the inverse of the CDF) at @var{x} of the
 ## Weibull distribution with scale parameter @var{scale} and shape
 ## parameter @var{shape}.
+##
+## Default values are @var{scale} = 1, @var{shape} = 1.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Quantile function of the Weibull distribution

-function inv = wblinv (x, scale, shape)
+function inv = wblinv (x, scale = 1, shape = 1)

   if (nargin < 1 || nargin > 3)
     print_usage ();
   endif

-  if (nargin < 3)
-    shape = 1;
-  endif
-
-  if (nargin < 2)
-    scale = 1;
-  endif
-
   if (!isscalar (scale) || !isscalar (shape))
     [retval, x, scale, shape] = common_size (x, scale, shape);
     if (retval > 0)
-      error ("wblinv: X, SCALE and SHAPE must be of common size or scalar");
+      error ("wblinv: X, SCALE, and SHAPE must be of common size or scalars");
     endif
   endif

-  inv = NaN (size (x));
-
-  ok = ((scale > 0) & (scale < Inf) & (shape > 0) & (shape < Inf));
+  if (iscomplex (x) || iscomplex (scale) || iscomplex (shape))
+    error ("wblinv: X, SCALE, and SHAPE must not be complex");
+  endif

-  k = find ((x == 0) & ok);
-  if (any (k))
-    inv(k) = 0;
+  if (isa (x, "single") || isa (scale, "single") || isa (shape, "single"))
+    inv = NaN (size (x), "single");
+  else
+    inv = NaN (size (x));
   endif

-  k = find ((x > 0) & (x < 1) & ok);
-  if (any (k))
-    if (isscalar (scale) && isscalar (shape))
-      inv(k) = scale * (- log (1 - x(k))) .^ (1 / shape);
-    else
-      inv(k) = scale(k) .* (- log (1 - x(k))) .^ (1 ./ shape(k));
-    endif
-  endif
+  ok = (scale > 0) & (scale < Inf) & (shape > 0) & (shape < Inf);
+
+  k = (x == 0) & ok;
+  inv(k) = 0;

-  k = find ((x == 1) & ok);
-  if (any (k))
-    inv(k) = Inf;
+  k = (x == 1) & ok;
+  inv(k) = Inf;
+
+  k = (x > 0) & (x < 1) & ok;
+  if (isscalar (scale) && isscalar (shape))
+    inv(k) = scale * (- log (1 - x(k))) .^ (1 / shape);
+  else
+    inv(k) = scale(k) .* (- log (1 - x(k))) .^ (1 ./ shape(k));
   endif

 endfunction
+
+
+%!shared x
+%! x = [-1 0 0.63212055882855778 1 2];
+%!assert(wblinv (x, ones(1,5), ones(1,5)), [NaN 0 1 Inf NaN], eps);
+%!assert(wblinv (x, 1, ones(1,5)), [NaN 0 1 Inf NaN], eps);
+%!assert(wblinv (x, ones(1,5), 1), [NaN 0 1 Inf NaN], eps);
+%!assert(wblinv (x, [1 -1 NaN Inf 1], 1), [NaN NaN NaN NaN NaN]);
+%!assert(wblinv (x, 1, [1 -1 NaN Inf 1]), [NaN NaN NaN NaN NaN]);
+%!assert(wblinv ([x(1:2) NaN x(4:5)], 1, 1), [NaN 0 NaN Inf NaN]);
+
+%% Test class of input preserved
+%!assert(wblinv ([x, NaN], 1, 1), [NaN 0 1 Inf NaN NaN], eps);
+%!assert(wblinv (single([x, NaN]), 1, 1), single([NaN 0 1 Inf NaN NaN]), eps("single"));
+%!assert(wblinv ([x, NaN], single(1), 1), single([NaN 0 1 Inf NaN NaN]), eps("single"));
+%!assert(wblinv ([x, NaN], 1, single(1)), single([NaN 0 1 Inf NaN NaN]), eps("single"));
+
+%% Test input validation
+%!error wblinv ()
+%!error wblinv (1,2,3,4)
+%!error wblinv (ones(3),ones(2),ones(2))
+%!error wblinv (ones(2),ones(3),ones(2))
+%!error wblinv (ones(2),ones(2),ones(3))
+%!error wblinv (i, 2, 2)
+%!error wblinv (2, i, 2)
+%!error wblinv (2, 2, i)
+
--- a/scripts/statistics/distributions/wblpdf.m
+++ b/scripts/statistics/distributions/wblpdf.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,7 +18,9 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} wblpdf (@var{x}, @var{scale}, @var{shape})
+## @deftypefn  {Function File} {} wblpdf (@var{x})
+## @deftypefnx {Function File} {} wblpdf (@var{x}, @var{scale})
+## @deftypefnx {Function File} {} wblpdf (@var{x}, @var{scale}, @var{shape})
 ## Compute the probability density function (PDF) at @var{x} of the
 ## Weibull distribution with scale parameter @var{scale} and shape
 ## parameter @var{shape} which is given by
@@ -27,57 +30,83 @@
 ## @ifnottex
 ##
 ## @example
-##    shape * scale^(-shape) * x^(shape-1) * exp(-(x/scale)^shape)
+##    shape * scale^(-shape) * x^(shape-1) * exp (-(x/scale)^shape)
 ## @end example
 ##
 ## @end ifnottex
 ## @noindent
 ## for @var{x} @geq{} 0.
+##
+## Default values are @var{scale} = 1, @var{shape} = 1.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: PDF of the Weibull distribution

-function pdf = wblpdf (x, scale, shape)
+function pdf = wblpdf (x, scale = 1, shape = 1)

   if (nargin < 1 || nargin > 3)
     print_usage ();
   endif

-  if (nargin < 3)
-    shape = 1;
-  endif
-
-  if (nargin < 2)
-    scale = 1;
-  endif
-
   if (!isscalar (scale) || !isscalar (shape))
     [retval, x, scale, shape] = common_size (x, scale, shape);
     if (retval > 0)
-      error ("wblpdf: X, SCALE and SHAPE must be of common size or scalar");
+      error ("wblpdf: X, SCALE, and SHAPE must be of common size or scalars");
     endif
   endif

-  pdf = NaN (size (x));
-  ok = ((scale > 0) & (scale < Inf) & (shape > 0) & (shape < Inf));
+  if (iscomplex (x) || iscomplex (scale) || iscomplex (shape))
+    error ("wblpdf: X, SCALE, and SHAPE must not be complex");
+  endif

-  k = find ((x > -Inf) & (x < 0) & ok);
-  if (any (k))
-    pdf(k) = 0;
+  if (isa (x, "single") || isa (scale, "single") || isa (shape, "single"))
+    pdf = NaN (size (x), "single");
+  else
+    pdf = NaN (size (x));
   endif

-  k = find ((x >= 0) & (x < Inf) & ok);
-  if (any (k))
-    if (isscalar (scale) && isscalar (shape))
-      pdf(k) = (shape .* (scale .^ -shape)
-                .* (x(k) .^ (shape - 1))
-                .* exp(- (x(k) / scale) .^ shape));
-    else
-      pdf(k) = (shape(k) .* (scale(k) .^ -shape(k))
-                .* (x(k) .^ (shape(k) - 1))
-                .* exp(- (x(k) ./ scale(k)) .^ shape(k)));
-    endif
+  ok = ((scale > 0) & (scale < Inf) & (shape > 0) & (shape < Inf));
+
+  k = (x < 0) & ok;
+  pdf(k) = 0;
+
+  k = (x >= 0) & (x < Inf) & ok;
+  if (isscalar (scale) && isscalar (shape))
+    pdf(k) = (shape * (scale .^ -shape)
+              .* (x(k) .^ (shape - 1))
+              .* exp (- (x(k) / scale) .^ shape));
+  else
+    pdf(k) = (shape(k) .* (scale(k) .^ -shape(k))
+              .* (x(k) .^ (shape(k) - 1))
+              .* exp (- (x(k) ./ scale(k)) .^ shape(k)));
   endif

 endfunction
+
+
+%!shared x,y
+%! x = [-1 0 0.5 1 Inf];
+%! y = [0, exp(-x(2:4)), NaN];
+%!assert(wblpdf (x, ones(1,5), ones(1,5)), y);
+%!assert(wblpdf (x, 1, ones(1,5)), y);
+%!assert(wblpdf (x, ones(1,5), 1), y);
+%!assert(wblpdf (x, [0 NaN Inf 1 1], 1), [NaN NaN NaN y(4:5)]);
+%!assert(wblpdf (x, 1, [0 NaN Inf 1 1]), [NaN NaN NaN y(4:5)]);
+%!assert(wblpdf ([x, NaN], 1, 1), [y, NaN]);
+
+%% Test class of input preserved
+%!assert(wblpdf (single([x, NaN]), 1, 1), single([y, NaN]));
+%!assert(wblpdf ([x, NaN], single(1), 1), single([y, NaN]));
+%!assert(wblpdf ([x, NaN], 1, single(1)), single([y, NaN]));
+
+%% Test input validation
+%!error wblpdf ()
+%!error wblpdf (1,2,3,4)
+%!error wblpdf (ones(3),ones(2),ones(2))
+%!error wblpdf (ones(2),ones(3),ones(2))
+%!error wblpdf (ones(2),ones(2),ones(3))
+%!error wblpdf (i, 2, 2)
+%!error wblpdf (2, i, 2)
+%!error wblpdf (2, 2, i)
+
--- a/scripts/statistics/distributions/wblrnd.m
+++ b/scripts/statistics/distributions/wblrnd.m
@@ -1,3 +1,4 @@
+## Copyright (C) 2011 Rik Wehbring
 ## Copyright (C) 1995-2011 Kurt Hornik
 ##
 ## This file is part of Octave.
@@ -17,78 +18,115 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn  {Function File} {} wblrnd (@var{scale}, @var{shape}, @var{r}, @var{c})
-## @deftypefnx {Function File} {} wblrnd (@var{scale}, @var{shape}, @var{sz})
-## Return an @var{r} by @var{c} matrix of random samples from the
-## Weibull distribution with parameters @var{scale} and @var{shape}
-## which must be scalar or of size @var{r} by @var{c}.  Or if @var{sz}
-## is a vector return a matrix of size @var{sz}.
+## @deftypefn  {Function File} {} wblrnd (@var{scale}, @var{shape})
+## @deftypefnx {Function File} {} wblrnd (@var{scale}, @var{shape}, @var{r})
+## @deftypefnx {Function File} {} wblrnd (@var{scale}, @var{shape}, @var{r}, @var{c}, @dots{})
+## @deftypefnx {Function File} {} wblrnd (@var{scale}, @var{shape}, [@var{sz}])
+## Return a matrix of random samples from the Weibull distribution with
+## parameters @var{scale} and @var{shape}.
 ##
-## If @var{r} and @var{c} are omitted, the size of the result matrix is
-## the common size of @var{alpha} and @var{sigma}.
+## When called with a single size argument, return a square matrix with
+## the dimension specified.  When called with more than one scalar argument the
+## first two arguments are taken as the number of rows and columns and any
+## further arguments specify additional matrix dimensions.  The size may also
+## be specified with a vector of dimensions @var{sz}.
+##
+## If no size arguments are given then the result matrix is the common size of
+## @var{scale} and @var{shape}.
 ## @end deftypefn

 ## Author: KH <Kurt.Hornik@wu-wien.ac.at>
 ## Description: Random deviates from the Weibull distribution

-function rnd = wblrnd (scale, shape, r, c)
+function rnd = wblrnd (scale, shape, varargin)

-  if (nargin > 1)
-    if (!isscalar(scale) || !isscalar(shape))
-      [retval, scale, shape] = common_size (scale, shape);
-      if (retval > 0)
-        error ("wblrnd: SCALE and SHAPE must be of common size or scalar");
-      endif
+  if (nargin < 2)
+    print_usage ();
+  endif
+
+  if (!isscalar (scale) || !isscalar (shape))
+    [retval, scale, shape] = common_size (scale, shape);
+    if (retval > 0)
+      error ("wblrnd: SCALE and SHAPE must be of common size or scalars");
     endif
   endif

-  if (nargin == 4)
-    if (! (isscalar (r) && (r > 0) && (r == round (r))))
-      error ("wblrnd: R must be a positive integer");
-    endif
-    if (! (isscalar (c) && (c > 0) && (c == round (c))))
-      error ("wblrnd: C must be a positive integer");
-    endif
-    sz = [r, c];
+  if (iscomplex (scale) || iscomplex (shape))
+    error ("wblrnd: SCALE and SHAPE must not be complex");
+  endif

-    if (any (size (scale) != 1)
-        && ((length (size (scale)) != length (sz))
-            || any (size (scale) != sz)))
-      error ("wblrnd: SCALE and SHAPE must be scalar or of size [R, C]");
-    endif
+  if (nargin == 2)
+    sz = size (scale);
   elseif (nargin == 3)
-    if (isscalar (r) && (r > 0))
-      sz = [r, r];
-    elseif (isvector(r) && all (r > 0))
-      sz = r(:)';
+    if (isscalar (varargin{1}) && varargin{1} >= 0)
+      sz = [varargin{1}, varargin{1}];
+    elseif (isrow (varargin{1}) && all (varargin{1} >= 0))
+      sz = varargin{1};
     else
-      error ("wblrnd: R must be a positive integer or vector");
+      error ("wblrnd: dimension vector must be row vector of non-negative integers");
     endif
+  elseif (nargin > 3)
+    if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin)))
+      error ("wblrnd: dimensions must be non-negative integers");
+    endif
+    sz = [varargin{:}];
+  endif

-    if (any (size (scale) != 1)
-        && ((length (size (scale)) != length (sz))
-            || any (size (scale) != sz)))
-      error ("wblrnd: SCALE and SHAPE must be scalar or of size SZ");
-    endif
-  elseif (nargin == 2)
-    sz = size(scale);
+  if (!isscalar (scale) && !isequal (size (scale), sz))
+    error ("wblrnd: SCALE and SHAPE must be scalar or of size SZ");
+  endif
+
+  if (isa (scale, "single") || isa (shape, "single"))
+    cls = "single";
   else
-    print_usage ();
+    cls = "double";
   endif

   if (isscalar (scale) && isscalar (shape))
-    if (scale > 0 && scale < Inf && shape > 0 && shape < Inf)
-      rnd = scale .* rande(sz) .^ (1./shape);
+    if ((scale > 0) && (scale < Inf) && (shape > 0) && (shape < Inf))
+      rnd = scale * rande (sz) .^ (1/shape);
     else
-      rnd = NaN (sz);
+      rnd = NaN (sz, cls);
     endif
   else
-    rnd = scale .* rande(sz) .^ (1./shape);
-    k = find ((scale <= 0) | (scale == Inf) | ((shape <= 0) & (shape == Inf)));
-    if (any(k))
-      rnd(k) = NaN;
-    endif
+    rnd = scale .* rande (sz) .^ (1./shape);
+
+    k = (scale <= 0) | (scale == Inf) | (shape <= 0) | (shape == Inf);
+    rnd(k) = NaN;
   endif

 endfunction

+
+%!assert(size (wblrnd (1,2)), [1, 1]);
+%!assert(size (wblrnd (ones(2,1), 2)), [2, 1]);
+%!assert(size (wblrnd (ones(2,2), 2)), [2, 2]);
+%!assert(size (wblrnd (1, 2*ones(2,1))), [2, 1]);
+%!assert(size (wblrnd (1, 2*ones(2,2))), [2, 2]);
+%!assert(size (wblrnd (1, 2, 3)), [3, 3]);
+%!assert(size (wblrnd (1, 2, [4 1])), [4, 1]);
+%!assert(size (wblrnd (1, 2, 4, 1)), [4, 1]);
+
+%% Test class of input preserved
+%!assert(class (wblrnd (1, 2)), "double");
+%!assert(class (wblrnd (single(1), 2)), "single");
+%!assert(class (wblrnd (single([1 1]), 2)), "single");
+%!assert(class (wblrnd (1, single(2))), "single");
+%!assert(class (wblrnd (1, single([2 2]))), "single");
+
+%% Test input validation
+%!error wblrnd ()
+%!error wblrnd (1)
+%!error wblrnd (ones(3),ones(2))
+%!error wblrnd (ones(2),ones(3))
+%!error wblrnd (i, 2)
+%!error wblrnd (2, i)
+%!error wblrnd (1,2, -1)
+%!error wblrnd (1,2, ones(2))
+%!error wblrnd (1, 2, [2 -1 2])
+%!error wblrnd (1,2, 1, ones(2))
+%!error wblrnd (1,2, 1, -1)
+%!error wblrnd (ones(2,2), 2, 3)
+%!error wblrnd (ones(2,2), 2, [3, 2])
+%!error wblrnd (ones(2,2), 2, 2, 3)
+
--- a/scripts/strings/base2dec.m
+++ b/scripts/strings/base2dec.m
@@ -28,10 +28,12 @@
 ## @end group
 ## @end example
 ##
-## If @var{s} is a matrix, returns a column vector with one value per
+## If @var{s} is a string matrix, return a column vector with one value per
 ## row of @var{s}.  If a row contains invalid symbols then the
-## corresponding value will be NaN@.  Rows are right-justified before
-## converting so that trailing spaces are ignored.
+## corresponding value will be NaN@.
+##
+## If @var{s} is a cell array of strings, return a column vector with one
+## value per cell element in @var{s}.
 ##
 ## If @var{base} is a string, the characters of @var{base} are used as the
 ## symbols for the digits of @var{s}.  Space (' ') may not be used as a
@@ -55,6 +57,12 @@
     print_usage ();
   endif

+  if (iscellstr (s))
+    s = char (s);
+  elseif (! ischar (s))
+    error ("base2dec: S must be a string or cellstring");
+  endif
+
   symbols = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
   if (ischar (base))
     symbols = base;
@@ -89,9 +97,11 @@

 endfunction

+
 %!assert(base2dec ("11120", 3), 123);
 %!assert(base2dec ("yyyzx", "xyz"), 123);
 %!assert(base2dec ("-1", 2), NaN);
+%!assert(base2dec ({"A1", "1A"}, 16), [161; 26]);

 %%Test input validation
 %!error base2dec ();
--- a/scripts/strings/bin2dec.m
+++ b/scripts/strings/bin2dec.m
@@ -28,8 +28,11 @@
 ## @end group
 ## @end example
 ##
-## If @var{s} is a string matrix, return a column vector of converted
-## numbers, one per row of @var{s}.  Invalid rows evaluate to NaN.
+## If @var{s} is a string matrix, return a column vector with one converted
+## number per row of @var{s}; Invalid rows evaluate to NaN@.
+##
+## If @var{s} is a cell array of strings, return a column vector with one
+## converted number per cell element in @var{s}.
 ## @seealso{dec2bin, base2dec, hex2dec}
 ## @end deftypefn

@@ -38,17 +41,19 @@

 function d = bin2dec (s)

-  if (nargin == 1 && ischar (s))
-    d = base2dec (s, 2);
-  else
+  if (nargin != 1)
     print_usage ();
   endif

+  d = base2dec (s, 2);
+
 endfunction

+
 %!assert(bin2dec ("0000"), 0);
 %!assert(bin2dec ("1110"), 14);
 %!assert(bin2dec ("11111111111111111111111111111111111111111111111111111"), 2^53-1);
+%!assert(bin2dec ({"1110", "1111"}), [14; 15]);

 %%Test input validation
 %!error bin2dec ();
--- a/scripts/strings/blanks.m
+++ b/scripts/strings/blanks.m
@@ -22,7 +22,7 @@
 ##
 ## @example
 ## @group
-## blanks(10);
+## blanks (10);
 ## whos ans;
 ##      @result{}
 ##       Attr Name        Size                     Bytes  Class
@@ -40,7 +40,7 @@

   if (nargin != 1)
     print_usage ();
-  elseif (! (isscalar (n) && n == round (n)))
+  elseif (! (isscalar (n) && n == fix (n) && n >= 0))
     error ("blanks: N must be a non-negative integer");
   endif

@@ -50,14 +50,16 @@

 endfunction

+
 ## There really isn't that much to test here
 %!assert(blanks (0), "")
 %!assert(blanks (5), "     ")
 %!assert(blanks (10), "          ")

-%!assert(strcmp (blanks (3), "   "));
+%% Test input validation
+%!error blanks ()
+%!error blanks (1, 2)
+%!error blanks (ones (2))
+%!error blanks (2.1)
+%!error blanks (-2)

-%!error blanks ();
-
-%!error blanks (1, 2);
-
--- a/scripts/strings/dec2base.m
+++ b/scripts/strings/dec2base.m
@@ -29,8 +29,9 @@
 ## @end group
 ## @end example
 ##
-## If @var{d} is a vector, return a string matrix with one row per value,
-## padded with leading zeros to the width of the largest value.
+## If @var{d} is a matrix or cell array, return a string matrix with one
+## row per element in @var{d}, padded with leading zeros to the width of
+## the largest value.
 ##
 ## If @var{base} is a string then the characters of @var{base} are used as
 ## the symbols for the digits of @var{d}.  Space (' ') may not be used
@@ -57,13 +58,17 @@
     print_usage ();
   endif

+  if (iscell (d))
+    d = cell2mat (d);
+  endif
+
   # Create column vector for algorithm
-  if (columns (d) > 1 || !isvector (d))
+  if (! iscolumn (d))
     d = d(:);
   endif

-  if (any (d < 0 | d != fix (d)))
-    error ("dec2base: input must be non-negative integers");
+  if (! isnumeric (d) || iscomplex (d) || any (d < 0 | d != fix (d)))
+    error ("dec2base: input must be real non-negative integers");
   endif

   symbols = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
@@ -93,7 +98,7 @@
   ## determine digits for each number
   digits = zeros (length (d), max_len);
   for k = max_len:-1:1
-    digits(:,k) = mod(d, base);
+    digits(:,k) = mod (d, base);
     d = round ((d - digits(:,k)) / base);
   endfor

@@ -112,41 +117,45 @@

 endfunction

+
 %!test
-%! s0='';
-%! for n=1:13
-%!   for b=2:16
-%!     pp=dec2base(b^n+1,b);
-%!     assert(dec2base(b^n,b),['1',s0,'0']);
-%!     assert(dec2base(b^n+1,b),['1',s0,'1']);
+%! s0 = '';
+%! for n = 1:13
+%!   for b = 2:16
+%!     pp = dec2base (b^n+1, b);
+%!     assert (dec2base(b^n, b), ['1',s0,'0']);
+%!     assert (dec2base(b^n+1, b), ['1',s0,'1']);
 %!   end
-%!   s0=[s0,'0'];
+%!   s0 = [s0,'0'];
 %! end

 %!test
 %! digits='0123456789ABCDEF';
-%! for n=1:13
-%!   for b=2:16
-%!     pm=dec2base(b^n-1,b);
-%!     assert(length(pm),n);
-%!     assert(all(pm==digits(b)));
+%! for n = 1:13
+%!   for b = 2:16
+%!     pm = dec2base(b^n-1, b);
+%!     assert (length (pm), n);
+%!     assert (all (pm==digits(b)));
 %!   end
 %! end

 %!test
-%! for b=2:16
-%!   assert(dec2base(0,b),'0');
+%! for b = 2:16
+%!   assert (dec2base (0, b), '0');
 %! end

-%!assert(dec2base(0,2,4), "0000");
-%!assert(dec2base(2^51-1,2), ...
+%!assert(dec2base (0, 2, 4), "0000");
+%!assert(dec2base (2^51-1, 2), ...
 %!       '111111111111111111111111111111111111111111111111111');
-%!assert(dec2base(uint64(2)^63-1,16), '7FFFFFFFFFFFFFFF');
+%!assert(dec2base(uint64(2)^63-1, 16), '7FFFFFFFFFFFFFFF');
+%!assert(dec2base({1, 2; 3, 4}, 2, 3), ["001"; "011"; "010"; "100"]);

 %%Test input validation
 %!error dec2base ()
 %!error dec2base (1)
 %!error dec2base (1, 2, 3, 4)
+%!error dec2base ("A")
+%!error dec2base (2i)
 %!error dec2base (-1)
 %!error dec2base (1.1)
 %!error dec2base (1,"ABA")
--- a/scripts/strings/dec2bin.m
+++ b/scripts/strings/dec2bin.m
@@ -28,8 +28,9 @@
 ## @end group
 ## @end example
 ##
-## If @var{d} is a vector, returns a string matrix, one row per value,
-## padded with leading zeros to the width of the largest value.
+## If @var{d} is a matrix or cell array, return a string matrix with one
+## row per element in @var{d}, padded with leading zeros to the width of
+## the largest value.
 ##
 ## The optional second argument, @var{len}, specifies the minimum
 ## number of digits in the result.
@@ -51,8 +52,10 @@

 endfunction

-%!assert(strcmp (dec2bin (14), "1110"));
-%!assert(strcmp (dec2bin (14, 6), "001110"));
+
+%!assert(dec2bin (14), "1110");
+%!assert(dec2bin (14, 6), "001110");
+%!assert(dec2bin ({1, 2; 3, 4}), ["001"; "011"; "010"; "100"]);

 %%Test input validation
 %!error dec2bin ();
--- a/scripts/strings/dec2hex.m
+++ b/scripts/strings/dec2hex.m
@@ -28,8 +28,9 @@
 ## @end group
 ## @end example
 ##
-## If @var{d} is a vector, return a string matrix, one row per value,
-## padded with leading zeros to the width of the largest value.
+## If @var{d} is a matrix or cell array, return a string matrix with one
+## row per element in @var{d}, padded with leading zeros to the width of
+## the largest value.
 ##
 ## The optional second argument, @var{len}, specifies the minimum
 ## number of digits in the result.
@@ -51,8 +52,10 @@

 endfunction

-%!assert(strcmpi (dec2hex (2748), "abc"));
-%!assert(strcmpi (dec2hex (2748, 5), "00abc"));
+
+%!assert(dec2hex (2748), "ABC");
+%!assert(dec2hex (2748, 5), "00ABC");
+%!assert(dec2hex ({2748, 2746}), ["ABC"; "ABA"]);

 %% Test input validation
 %!error dec2hex ();
--- a/scripts/strings/findstr.m
+++ b/scripts/strings/findstr.m
@@ -17,20 +17,24 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {} findstr (@var{s}, @var{t}, @var{overlap})
+## @deftypefn  {Function File} {} findstr (@var{s}, @var{t})
+## @deftypefnx {Function File} {} findstr (@var{s}, @var{t}, @var{overlap})
 ## Return the vector of all positions in the longer of the two strings
 ## @var{s} and @var{t} where an occurrence of the shorter of the two starts.
-## If the optional argument @var{overlap} is nonzero, the returned vector
+## If the optional argument @var{overlap} is true, the returned vector
 ## can include overlapping positions (this is the default).  For example:
 ##
 ## @example
 ## @group
 ## findstr ("ababab", "a")
-##      @result{} [1, 3, 5]
+##      @result{} [1, 3, 5];
 ## findstr ("abababa", "aba", 0)
 ##      @result{} [1, 5]
 ## @end group
 ## @end example
+##
+## @strong{Caution:} @code{findstr} is scheduled for deprecation.  Use
+## @code{strfind} in all new code.
 ## @seealso{strfind, strmatch, strcmp, strncmp, strcmpi, strncmpi, find}
 ## @end deftypefn

@@ -40,7 +44,7 @@
 ## Author: Kurt Hornik <Kurt.Hornik@wu-wien.ac.at>
 ## Adapted-By: jwe

-function v = findstr (s, t, overlap)
+function v = findstr (s, t, overlap = true)

   if (nargin < 2 || nargin > 3)
     print_usage ();
@@ -50,15 +54,9 @@
     error ("findstr: arguments must have only one non-singleton dimension");
   endif

-  if (nargin == 2)
-    overlap = 1;
-  endif
-
   ## Make S be the longer string.
   if (length (s) < length (t))
-    tmp = s;
-    s = t;
-    t = tmp;
+    [s, t] = deal (t, s);
   endif

   l_s = length (s);
@@ -126,18 +124,20 @@
     v = [];
   endif

-  ## Always return a column vector, because that's what the old one did.
-  if (rows (v) > 1)
+  ## Always return a row vector, because that's what the old one did.
+  if (iscolumn (v))
     v = v.';
   endif

 endfunction

-%!assert ((findstr ("abababa", "a") == [1, 3, 5, 7]
-%! && findstr ("abababa", "aba") == [1, 3, 5]
-%! && findstr ("abababa", "aba", 0) == [1, 5]));
+
+%!assert (findstr ("abababa", "a"), [1, 3, 5, 7])
+%!assert (findstr ("abababa", "aba"), [1, 3, 5]);
+%!assert (findstr ("aba", "abababa", 0), [1, 5]);

-%!error findstr ();
+%% Test input validation
+%!error findstr ()
+%!error findstr ("foo", "bar", 3, 4);
+%!error findstr (["AB" ; "CD"], "C");

-%!error findstr ("foo", "bar", 3, 4);
-
--- a/scripts/strings/hex2dec.m
+++ b/scripts/strings/hex2dec.m
@@ -30,8 +30,12 @@
 ## @end group
 ## @end example
 ##
-## If @var{s} is a string matrix, returns a column vector of converted
-## numbers, one per row of @var{s}.  Invalid rows evaluate to NaN.
+## If @var{s} is a string matrix, return a column vector with one converted
+## number per row of @var{s}; Invalid rows evaluate to NaN@.
+##
+## If @var{s} is a cell array of strings, return a column vector with one
+## converted number per cell element in @var{s}.
+##
 ## @seealso{dec2hex, base2dec, bin2dec}
 ## @end deftypefn

@@ -40,17 +44,19 @@

 function d = hex2dec (s)

-  if (nargin == 1 && ischar (s))
-    d = base2dec (s, 16);
-  else
+  if (nargin != 1)
     print_usage ();
   endif

+  d = base2dec (s, 16);
+
 endfunction

+
 %!assert(hex2dec ("0000"), 0);
 %!assert(hex2dec ("1FFFFFFFFFFFFF"), 2^53-1);
-%!assert(hex2dec ("12b") == 299 && hex2dec ("12B") == 299);
+%!assert(hex2dec (["12b"; "12B"]), [299; 299]);
+%!assert(hex2dec ({"A1", "1A"}), [161; 26]);

 %%Test input validation
 %!error hex2dec ();
--- a/scripts/strings/mat2str.m
+++ b/scripts/strings/mat2str.m
@@ -18,20 +18,19 @@

 ## -*- texinfo -*-
 ## @deftypefn  {Function File} {@var{s} =} mat2str (@var{x}, @var{n})
-## @deftypefnx {Function File} {@var{s} =} mat2str (@dots{}, 'class')
-##
+## @deftypefnx {Function File} {@var{s} =} mat2str (@var{x}, @var{n}, "class")
 ## Format real/complex numerical matrices as strings.  This function
 ## returns values that are suitable for the use of the @code{eval}
 ## function.
 ##
 ## The precision of the values is given by @var{n}.  If @var{n} is a
 ## scalar then both real and imaginary parts of the matrix are printed
-## to the same precision.  Otherwise @code{@var{n} (1)} defines the
-## precision of the real part and @code{@var{n} (2)} defines the
+## to the same precision.  Otherwise @code{@var{n}(1)} defines the
+## precision of the real part and @code{@var{n}(2)} defines the
 ## precision of the imaginary part.  The default for @var{n} is 15.
 ##
-## If the argument 'class' is given, then the class of @var{x} is
-## included in the string in such a way that the eval will result in the
+## If the argument "class" is given, then the class of @var{x} is
+## included in the string in such a way that @code{eval} will result in the
 ## construction of a matrix of the same class.
 ##
 ## @example
@@ -42,7 +41,7 @@
 ## mat2str ([ -1/3 +i/7; 1/3 -i/7 ], [4 2])
 ##      @result{} "[-0.3333+0i,0+0.14i;0.3333+0i,-0-0.14i]"
 ##
-## mat2str (int16([1 -1]), 'class')
+## mat2str (int16([1 -1]), "class")
 ##      @result{} "int16([1,-1])"
 ## @end group
 ## @end example
@@ -54,9 +53,16 @@

 function s = mat2str (x, n, cls)

+  if (nargin < 1 || nargin > 3 || ! (isnumeric (x) || islogical (x)))
+    print_usage ();
+  endif
+
+  if (ndims (x) > 2)
+    error ("mat2str: X must be two dimensional");
+  endif
+
   if (nargin < 2 || isempty (n))
-    ## Default precision
-    n = 15;
+    n = 15;   # Default precision
   endif

   if (nargin < 3)
@@ -68,14 +74,6 @@
     endif
   endif

-  if (nargin < 1 || nargin > 3 || ! (isnumeric (x) || islogical (x)))
-    print_usage ();
-  endif
-
-  if (ndims (x) > 2)
-    error ("mat2str: X must be two dimensional");
-  endif
-
   x_islogical = islogical (x);
   x_iscomplex = iscomplex (x);

@@ -120,21 +118,32 @@

     s = cstrcat ("[", s);
     s(end) = "]";
-    ind = find (s == ",");
+    idx = find (s == ",");
     nc = columns (x);
-    s(ind(nc:nc:end)) = ";";
+    s(idx(nc:nc:end)) = ";";
   endif

   if (strcmp ("class", cls))
-    s = cstrcat (class(x), "(", s, ")");
+    s = cstrcat (class (x), "(", s, ")");
   endif
+
 endfunction

+
+%!assert (mat2str (0.7), "0.7");
+%!assert (mat2str (pi), "3.14159265358979");
+%!assert (mat2str (pi, 5), "3.1416");
+%!assert (mat2str (single (pi), 5, "class"), "single(3.1416)");
 %!assert (mat2str ([-1/3 + i/7; 1/3 - i/7], [4 2]), "[-0.3333+0.14i;0.3333-0.14i]")
 %!assert (mat2str ([-1/3 +i/7; 1/3 -i/7], [4 2]), "[-0.3333+0i,0+0.14i;0.3333+0i,-0-0.14i]")
 %!assert (mat2str (int16 ([1 -1]), 'class'), "int16([1,-1])")
-
 %!assert (mat2str (true), "true");
 %!assert (mat2str (false), "false");
 %!assert (mat2str (logical (eye (2))), "[true,false;false,true]");
-%!assert (mat2str (0.7), "0.7")
+
+%% Test input validation
+%!error mat2str ()
+%!error mat2str (1,2,3,4)
+%!error mat2str (["Hello"])
+%!error mat2str (ones(3,3,2))
+
--- a/scripts/strings/regexptranslate.m
+++ b/scripts/strings/regexptranslate.m
@@ -18,14 +18,14 @@

 ## -*- texinfo -*-
 ## @deftypefn {Function File} {} regexptranslate (@var{op}, @var{s})
-## Translate a string for use in a regular expression.  This might
+## Translate a string for use in a regular expression.  This may
 ## include either wildcard replacement or special character escaping.
-## The behavior can be controlled by the @var{op} that can have the
+## The behavior is controlled by @var{op} which can take the following
 ## values
 ##
 ## @table @asis
 ## @item "wildcard"
-## The wildcard characters @code{.}, @code{*} and @code{?} are replaced
+## The wildcard characters @code{.}, @code{*}, and @code{?} are replaced
 ## with wildcards that are appropriate for a regular expression.
 ## For example:
 ##
@@ -57,29 +57,31 @@
     print_usage ();
   endif

-  if (ischar (op))
-    op = tolower (op);
-    if (strcmp ("wildcard", op))
-      y = regexprep (regexprep (regexprep (s, '\.', '\.'), '\*',
-                                '.*'), '\?', '.');
-    elseif (strcmp ("escape", op))
-      ch = {'\$', '\.', '\?', '\[', '\]'};
-      y = s;
-      for i = 1 : length (ch)
-        y = regexprep (y, ch{i}, ch{i});
-      endfor
-    else
-      error ("regexptranslate: unexpected operation");
-    endif
+  if (! ischar (op))
+    error ("regexptranslate: operation OP must be a string");
+  endif
+
+  op = tolower (op);
+  if (strcmp ("wildcard", op))
+    y = regexprep (regexprep (regexprep (s, '\.', '\.'),
+                                            '\*', '.*'),
+                                            '\?', '.');
+  elseif (strcmp ("escape", op))
+    y = regexprep (s, '([^\w])', '\$1');
   else
-    error ("regexptranslate: expecting operation to be a string");
+    error ("regexptranslate: invalid operation OP");
   endif
+
 endfunction

-%!error <Invalid call to regexptranslate> regexptranslate ();
-%!error <Invalid call to regexptranslate> regexptranslate ("wildcard");
-%!error <Invalid call to regexptranslate> regexptranslate ("a", "b", "c");
-%!error <unexpected operation> regexptranslate ("foo", "abc");
-%!error <expecting operation to be a string> regexptranslate (10, "abc");
+
 %!assert (regexptranslate ("wildcard", "/a*b?c."), "/a.*b.c\\.")
-%!assert (regexptranslate ("escape", '$.?[]'), '\$\.\?\[\]')
+%!assert (regexptranslate ("escape", '$.?[abc]'), '\$\.\?\[abc\]')
+
+%% Test input validation
+%!error <Invalid call to regexptranslate> regexptranslate ()
+%!error <Invalid call to regexptranslate> regexptranslate ("wildcard")
+%!error <Invalid call to regexptranslate> regexptranslate ("a", "b", "c")
+%!error <invalid operation> regexptranslate ("foo", "abc")
+%!error <operation OP must be a string> regexptranslate (10, "abc")
+
--- a/scripts/strings/str2num.m
+++ b/scripts/strings/str2num.m
@@ -17,7 +17,7 @@
 ## <http://www.gnu.org/licenses/>.

 ## -*- texinfo -*-
-## @deftypefn {Function File} {@var{x} =} str2num (@var{s})
+## @deftypefn  {Function File} {@var{x} =} str2num (@var{s})
 ## @deftypefnx {Function File} {[@var{x}, @var{state}] =} str2num (@var{s})
 ## Convert the string (or character array) @var{s} to a number (or an
 ## array).  Examples:
@@ -35,13 +35,15 @@
 ## @end example
 ##
 ## The optional second output, @var{state}, is logically true when the
-## coversion is successful. If the conversion fails the numeric output,
+## coversion is successful.  If the conversion fails the numeric output,
 ## @var{x}, is empty and @var{state} is false.
 ##
 ## @strong{Caution:} As @code{str2num} uses the @code{eval} function
 ## to do the conversion, @code{str2num} will execute any code contained
 ## in the string @var{s}.  Use @code{str2double} for a safer and faster
 ## conversion.
+##
+## For cell array of strings use @code{str2double}.
 ## @seealso{str2double, eval}
 ## @end deftypefn

@@ -49,31 +51,37 @@

 function [m, state] = str2num (s)

-  if (nargin == 1 && ischar (s))
-    [nr, nc] = size (s);
-    sep = ";";
-    sep = sep (ones (nr, 1), 1);
-    s = sprintf ("m = [%s];", reshape ([s, sep]', 1, nr * (nc + 1)));
-    state = true;
-    eval (s, "m = []; state = false;");
-    if (ischar (m))
-      m = [];
-      state = false;
-    endif
-  else
+  if (nargin != 1)
     print_usage ();
   endif
+
+  if (! ischar (s))
+    error ("str2num: S must be a string or string array");
+  endif
+
+  [nr, nc] = size (s);
+  sep = repmat (";", nr, 1);
+  s = sprintf ("m = [%s];", reshape ([s, sep]', 1, nr * (nc + 1)));
+  state = true;
+  eval (s, "m = []; state = false;");
+  if (ischar (m))
+    m = [];
+    state = false;
+  endif

 endfunction

-%!assert(str2num ("-1.3e2") == -130 && str2num ("[1, 2; 3, 4]") == [1, 2; 3, 4]);
+
+%!assert(str2num ("-1.3e2"), -130);
+%!assert(str2num ("[1, 2; 3, 4]"), [1, 2; 3, 4]);

-%!error str2num ();
-
-%!error str2num ("string", 1);
+%% Test input validation
+%!error str2num ()
+%!error str2num ("string", 1)
+%!error str2num ({"string"})

 %!test
 %! [x, state] = str2num ("pi");
-%! assert (state)
+%! assert (state);
 %! [x, state] = str2num (tmpnam);
-%! assert (! state)
+%! assert (! state);
--- a/scripts/time/weekday.m
+++ b/scripts/time/weekday.m
@@ -61,7 +61,7 @@

   if (nargout > 1)
     if (strcmpi (format, "long"))
-      names = {"Sunday" "Monday" "Tuesday" "Wednesday" "Thursday"
+      names = {"Sunday" "Monday" "Tuesday" "Wednesday" "Thursday" \
                "Friday" "Saturday"};
     else
       names = {"Sun" "Mon" "Tue" "Wed" "Thu" "Fri" "Sat"};
@@ -96,6 +96,12 @@
 %!assert(weekday('7-Feb-2008'),5)
 ## Test fractional dates
 %!assert(weekday(728647.1),2)
+## Test "long" option
+%!test
+%! [a, b] = weekday ("25-Dec-1994", "long");
+%! assert (a, 1);
+%! assert (b, "Sunday");
+
 # demos
 %!demo
 %! [n, s] = weekday (now ())
--- a/src/DLD-FUNCTIONS/rand.cc
+++ b/src/DLD-FUNCTIONS/rand.cc
@@ -1019,10 +1019,10 @@
 @deftypefn  {Loadable Function} {} randperm (@var{n})\n\
 @deftypefnx {Loadable Function} {} randperm (@var{n}, @var{m})\n\
 Return a row vector containing a random permutation of @code{1:@var{n}}.\n\
-If @var{m} is supplied, return @var{m} permutations,\n\
-one in each row of an @nospell{MxN} matrix.  The complexity is O(M*N) in both\n\
-time and memory.  The randomization is performed using rand().\n\
-All permutations are equally likely.\n\
+If @var{m} is supplied, return @var{m} unique entries, sampled without\n\
+replacement from @code{1:@var{n}}. The complexity is O(N) in memory and \n\
+O(M) in time. The randomization is performed using rand(). All\n\
+permutations are equally likely.\n\
 @seealso{perms}\n\
 @end deftypefn")
 {
@@ -1033,54 +1033,46 @@
     {
       octave_idx_type n, m;

+      n = args(0).idx_type_value (true);
+
       if (nargin == 2)
         m = args(1).idx_type_value (true);
       else
-        m = 1;
-
-      n = args(0).idx_type_value (true);
+        m = n;

       if (m < 0 || n < 0)
         error ("randperm: M and N must be non-negative");

+      if (m > n)
+        error ("randperm: M must be less than or equal to N");
+
       if (! error_state)
         {
           // Generate random numbers.
-          NDArray r = octave_rand::nd_array (dim_vector (m, n));
+          NDArray r = octave_rand::nd_array (dim_vector (1, m));

-          // Create transposed to allow faster access.
-          Array<octave_idx_type> idx (dim_vector (n, m));
+          Array<octave_idx_type> idx (dim_vector (1, n));

           double *rvec = r.fortran_vec ();

           octave_idx_type *ivec = idx.fortran_vec ();

-          // Perform the Knuth shuffle.
-          for (octave_idx_type j = 0; j < m; j++)
-            {
-              for (octave_idx_type i = 0; i < n; i++)
-                ivec[i] = i;
+          for (octave_idx_type i = 0; i < n; i++)
+            ivec[i] = i;

-              for (octave_idx_type i = 0; i < n; i++)
-                {
-                  octave_idx_type k = i + gnulib::floor (rvec[i] * (n - i));
-                  std::swap (ivec[i], ivec[k]);
-                }
-
-              ivec += n;
-              rvec += n;
+          // Perform the Knuth shuffle of the first m entries
+          for (octave_idx_type i = 0; i < m; i++)
+            {
+              octave_idx_type k = i + gnulib::floor (rvec[i] * (n - i));
+              std::swap (ivec[i], ivec[k]);
             }

-          // Transpose.
-          idx = idx.transpose ();
+          // Convert to doubles, reusing r.
+          for (octave_idx_type i = 0; i < m; i++)
+            rvec[i] = ivec[i] + 1;

-          // Re-fetch the pointers.
-          ivec = idx.fortran_vec ();
-          rvec = r.fortran_vec ();
-
-          // Convert to doubles, reusing r.
-          for (octave_idx_type i = 0, l = m*n; i < l; i++)
-            rvec[i] = ivec[i] + 1;
+          if (m < n)
+            idx.resize (dim_vector (1, m));

           // Now create an array object with a cached idx_vector.
           retval = new octave_matrix (r, idx_vector (idx));
@@ -1093,6 +1085,6 @@
 }

 /*
-%!assert(sort(randperm(20)),1:20)
-%!assert(sort(randperm(20,50),2),repmat(1:20,50,1))
+%!assert(sort (randperm (20)),1:20)
+%!assert(length (randperm (20,10)), 10)
 */
--- a/src/OPERATORS/op-fcm-fcm.cc
+++ b/src/OPERATORS/op-fcm-fcm.cc
@@ -214,7 +214,9 @@

 DEFNDASSIGNOP_FN (assign, float_complex_matrix, float_complex_matrix,
                   float_complex_array, assign)
-DEFNDASSIGNOP_FN (dbl_assign, float_complex_matrix, complex_matrix,
+DEFNDASSIGNOP_FN (dbl_clx_assign, float_complex_matrix, complex_matrix,
+                  float_complex_array, assign)
+DEFNDASSIGNOP_FN (dbl_assign, float_complex_matrix, matrix,
                   float_complex_array, assign)

 DEFNULLASSIGNOP_FN (null_assign, float_complex_matrix, delete_elements)
@@ -308,7 +310,9 @@
   INSTALL_ASSIGNOP (op_asn_eq, octave_float_complex_matrix,
                     octave_float_complex_matrix, assign);
   INSTALL_ASSIGNOP (op_asn_eq, octave_float_complex_matrix,
-                    octave_complex_matrix, dbl_assign);
+                    octave_complex_matrix, dbl_clx_assign);
+  INSTALL_ASSIGNOP (op_asn_eq, octave_float_complex_matrix,
+                    octave_matrix, dbl_assign);

   INSTALL_ASSIGNOP (op_asn_eq, octave_float_complex_matrix,
                     octave_null_matrix, null_assign);
--- a/src/OPERATORS/op-m-s.cc
+++ b/src/OPERATORS/op-m-s.cc
@@ -29,6 +29,7 @@
 #include "ov.h"
 #include "ov-re-mat.h"
 #include "ov-flt-re-mat.h"
+#include "ov-flt-cx-mat.h"
 #include "ov-scalar.h"
 #include "ov-typeinfo.h"
 #include "ops.h"
@@ -106,6 +107,7 @@

 DEFNDASSIGNOP_FN (assign, matrix, scalar, scalar, assign)
 DEFNDASSIGNOP_FN (sgl_assign, float_matrix, scalar, float_scalar, assign)
+DEFNDASSIGNOP_FN (clx_sgl_assign, float_complex_matrix, scalar, float_complex, assign)

 DEFNDASSIGNOP_OP (assign_add, matrix, scalar, scalar, +=)
 DEFNDASSIGNOP_OP (assign_sub, matrix, scalar, scalar, -=)
@@ -144,6 +146,7 @@

   INSTALL_ASSIGNOP (op_asn_eq, octave_matrix, octave_scalar, assign);
   INSTALL_ASSIGNOP (op_asn_eq, octave_float_matrix, octave_scalar, sgl_assign);
+  INSTALL_ASSIGNOP (op_asn_eq, octave_float_complex_matrix, octave_scalar, clx_sgl_assign);

   INSTALL_ASSIGNOP (op_add_eq, octave_matrix, octave_scalar, assign_add);
   INSTALL_ASSIGNOP (op_sub_eq, octave_matrix, octave_scalar, assign_sub);