diff scripts/statistics/distributions/discrete_cdf.m @ 13171:19b9f17d22af

Overhaul of statistical distribution functions Support class "single" 75% reduction in memory usage More Matlab compatibility for corner cases * betacdf.m, betainv.m, betapdf.m, betarnd.m, binocdf.m, binoinv.m, binopdf.m, binornd.m, cauchy_cdf.m, cauchy_inv.m, cauchy_pdf.m, cauchy_rnd.m, chi2cdf.m, chi2inv.m, chi2pdf.m, chi2rnd.m, discrete_cdf.m, discrete_inv.m, discrete_pdf.m, discrete_rnd.m, empirical_cdf.m, empirical_inv.m, empirical_pdf.m, empirical_rnd.m, expcdf.m, expinv.m, exppdf.m, exprnd.m, fcdf.m, finv.m, fpdf.m, frnd.m, gamcdf.m, gaminv.m, gampdf.m, gamrnd.m, geocdf.m, geoinv.m, geopdf.m, geornd.m, hygecdf.m, hygeinv.m, hygepdf.m, hygernd.m, kolmogorov_smirnov_cdf.m, laplace_cdf.m, laplace_inv.m, laplace_pdf.m, laplace_rnd.m, logistic_cdf.m, logistic_inv.m, logistic_pdf.m, logistic_rnd.m, logncdf.m, logninv.m, lognpdf.m, lognrnd.m, nbincdf.m, nbininv.m, nbinpdf.m, nbinrnd.m, normcdf.m, norminv.m, normpdf.m, normrnd.m, poisscdf.m, poissinv.m, poisspdf.m, poissrnd.m, stdnormal_cdf.m, stdnormal_inv.m, stdnormal_pdf.m, stdnormal_rnd.m, tcdf.m, tinv.m, tpdf.m, trnd.m, unidcdf.m, unidinv.m, unidpdf.m, unidrnd.m, unifcdf.m, unifinv.m, unifpdf.m, unifrnd.m, wblcdf.m, wblinv.m, wblpdf.m, wblrnd.m: Return "single" outputs for "single" inputs, Use logical indexing rather than find() for 75% memory savings, Add tests for all functions, Use consistent documentation across all functions, More Matlab compatibilitcy for corner cases.
author Rik <octave@nomad.inbox5.com>
date Tue, 20 Sep 2011 12:13:13 -0700
parents fd0a3ac60b0e
children 72c96de7a403
line wrap: on
line diff
--- 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])
+