Mercurial > hg > octave-terminal
changeset 2538:6f71af650490
[project @ 1996-11-19 21:41:48 by jwe]
author | jwe |
---|---|
date | Tue, 19 Nov 1996 21:44:36 +0000 |
parents | 80b982e7f4b1 |
children | 1dca28c213f0 |
files | doc/interpreter/arith.texi doc/interpreter/signal.texi scripts/miscellaneous/bincoeff.m scripts/miscellaneous/xor.m |
diffstat | 4 files changed, 171 insertions(+), 6 deletions(-) [+] |
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--- a/doc/interpreter/arith.texi +++ b/doc/interpreter/arith.texi @@ -115,14 +115,46 @@ see @ref{Linear Algebra}. @end deftypefn -@deftypefn {Mapping Function} {} log2 (@var{x}) -Compute the base-2 logarithm of @var{x}. +@deftypefn {Mapping Function} {@var{y} =} log2 (@var{x}) +@deftypefnx {Mapping Function} {[@var{f}, @var{e}]} log2 (@var{x}) +Compute the base-2 logarithm of @var{x}. With two outputs, returns +@var{f} and @var{e} such that +@iftex +@tex + $1/2 <= |f| < 1$ and $x = f * 2^e$. +@end tex +@end iftex +@ifinfo + 1/2 <= abs(f) < 1 and x = f * 2^e. +@end ifinfo @end deftypefn @deftypefn {Mapping Function} {} log10 (@var{x}) Compute the base-10 logarithm of @var{x}. @end deftypefn +@deftypefn {Mapping Function} {} pow2 (@var{x}) +@deftypefnx {Mapping Function} {} pow2 (@var{f}, @var{e}) +With one argument, computes +@iftex +@tex + $2^x$ +@end tex +@end iftex +@ifinfo + 2 .^ x +@end ifinfo +for each element of @var{x}. With two arguments, returns +@iftex +@tex + $f 2^e$. +@end tex +@end iftex +@ifinfo + f .* (2 .^ e). +@end ifinfo +@end deftypefn + @deftypefn {Mapping Function} {} sqrt (@var{x}) Compute the square root of @var{x}. To compute the matrix square root, see @ref{Linear Algebra}. @@ -159,6 +191,13 @@ agree, or if either of the arguments is complex. @end deftypefn +@deftypefn {Mapping Function} {} xor (@var{x}, @var{y}) +Return the `exclusive or' of the entries of @var{x} and @var{y}. +For boolean expressions @var{x} and @var{y}, +@code{xor (@var{x}, @var{y})} is true if and only if either @var{x} or +@var{y} is true. +@end deftypefn + @node Complex Arithmetic, Trigonometry, Utility Functions, Arithmetic @section Complex Arithmetic @@ -344,6 +383,10 @@ compatible dimensions. @end deftypefn +@deftypefn {Mapping Function} {} bincoeff (@var{n}, @var{k}) +Returns the binomial coefficient of @var{n} and @var{k}. +@end deftypefn + @deftypefn {Mapping Function} {} erf (@var{z}) Computes the error function, @iftex @@ -369,10 +412,9 @@ Computes the complementary error function, @code{1 - erf (@var{z})}. @end deftypefn -@c XXX FIXME XXX -- this isn't actually distributed with Octave yet. -@c -@c @item erfinv -@c Computes the inverse of the error function. +@deftypefn {Mapping Function} {} erfinv (@var{z}) +Computes the inverse of the error function. +@end deftypefn @deftypefn {Mapping Function} {} gamma (@var{z}) Computes the Gamma function,
--- a/doc/interpreter/signal.texi +++ b/doc/interpreter/signal.texi @@ -9,6 +9,17 @@ functions. If you would like to help improve Octave in this area, please contact @code{bug-octave@@bevo.che.wisc.edu}. +@deftypefn {Function File} {} detrend (@var{x}, @var{p}) +If @var{x} is a vector, @code{detrend (@var{x}, @var{p})} removes the +best fit of a polynomial of order @var{p} from the data @var{x}. + +If @var{x} is a matrix, @code{detrend (@var{x}, @var{p})} does the same +for each column in @var{x}. + +The second argument is optional. If it is not specified, a value of 1 +is assumed. This corresponds to removing a linear trend. +@end deftypefn + @deftypefn {Function} {} fft (@var{a} [, @var{n}]) Compute the FFT of @var{a} using subroutines from FFTPACK. If @var{a} is a matrix, @code{fft} computes the FFT for each column of @var{a}.
new file mode 100644 --- /dev/null +++ b/scripts/miscellaneous/bincoeff.m @@ -0,0 +1,73 @@ +## Copyright (C) 1995, 1996 Kurt Hornik +## +## This program 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 2, or (at your option) +## any later version. +## +## This program 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 this file. If not, write to the Free Software Foundation, +## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +## usage: bincoeff (n, k) +## +## Returns the binomial coefficient of n and k. + +## Author: KH <Kurt.Hornik@ci.tuwien.ac.at> +## Created: 8 October 1994 +## Adapted-By: jwe + +function b = bincoeff (n, k) + + if (nargin != 2) + usage ("bincoeff (n, k)"); + endif + + [retval, n, k] = common_size (n, k); + if (retval > 0) + error ("bincoeff: n and k must be of common size or scalars"); + endif + + [r, c] = size (n); + s = r * c; + n = reshape (n, s, 1); + k = reshape (k, s, 1); + b = zeros (s, 1); + + ind = find (! (k >= 0) | (k != real (round (k))) | isnan (n)); + if (any (ind)) + b(ind) = NaN * ones (length (ind), 1); + endif + + ind = find (k == 0); + if (any (ind)) + b(ind) = ones (length (ind), 1); + endif + + ind = find ((k > 0) & ((n == real (round (n))) & (n < 0))); + if any (ind) + b(ind) = (-1) .^ k(ind) .* exp (lgamma (abs (n(ind)) + k(ind)) ... + - lgamma (k(ind) + 1) - lgamma (abs (n(ind)))); + endif + + ind = find ((k > 0) & ((n != real (round (n))) | (n >= k))); + if (length (ind) > 0) + b(ind) = exp (lgamma (n(ind) + 1) - lgamma (k(ind) + 1) ... + - lgamma (n(ind) - k(ind) + 1)); + endif + + ## clean up rounding errors + ind = find (n == round (n)); + if (any (ind)) + b(ind) = round (b(ind)); + endif + + b = reshape (b, r, c); + +endfunction +
new file mode 100644 --- /dev/null +++ b/scripts/miscellaneous/xor.m @@ -0,0 +1,39 @@ +## Copyright (C) 1995, 1996 Kurt Hornik +## +## This program 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 2, or (at your option) +## any later version. +## +## This program 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 this file. If not, write to the Free Software Foundation, +## 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + +## usage: xor (x, y) +## +## Returns the "exclusive or" of the entries of x and y. +## For boolean expressions x and y, xor (x, y) is true iff either x +## or y is true. + +## Author: KH <Kurt.Hornik@ci.tuwien.ac.at> +## Created: 16 September 1994 +## Adapted-By: jwe + +function z = xor (x, y) + + if (nargin != 2) + usage ("xor (x, y)"); + endif + + if (is_scalar (x) || is_scalar (y) || size (x) == size (y)) + error ("xor: x and y must be of common size or scalars"); + endif + + z = (x | y) - (x & y); + +endfunction