X-Git-Url: https://git.creatis.insa-lyon.fr/pubgit/?p=CreaPhase.git;a=blobdiff_plain;f=octave_packages%2Fstatistics-1.1.3%2Fnormstat.m;fp=octave_packages%2Fstatistics-1.1.3%2Fnormstat.m;h=3e590fe1dc8e06efb88fe3ed8347811866279c34;hp=0000000000000000000000000000000000000000;hb=f5f7a74bd8a4900f0b797da6783be80e11a68d86;hpb=1705066eceaaea976f010f669ce8e972f3734b05 diff --git a/octave_packages/statistics-1.1.3/normstat.m b/octave_packages/statistics-1.1.3/normstat.m new file mode 100644 index 0000000..3e590fe --- /dev/null +++ b/octave_packages/statistics-1.1.3/normstat.m @@ -0,0 +1,122 @@ +## Copyright (C) 2006, 2007 Arno Onken +## +## 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 3 of the License, 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 program; if not, see . + +## -*- texinfo -*- +## @deftypefn {Function File} {[@var{mn}, @var{v}] =} normstat (@var{m}, @var{s}) +## Compute mean and variance of the normal distribution. +## +## @subheading Arguments +## +## @itemize @bullet +## @item +## @var{m} is the mean of the normal distribution +## +## @item +## @var{s} is the standard deviation of the normal distribution. +## @var{s} must be positive +## @end itemize +## @var{m} and @var{s} must be of common size or one of them must be +## scalar +## +## @subheading Return values +## +## @itemize @bullet +## @item +## @var{mn} is the mean of the normal distribution +## +## @item +## @var{v} is the variance of the normal distribution +## @end itemize +## +## @subheading Examples +## +## @example +## @group +## m = 1:6; +## s = 0:0.2:1; +## [mn, v] = normstat (m, s) +## @end group +## +## @group +## [mn, v] = normstat (0, s) +## @end group +## @end example +## +## @subheading References +## +## @enumerate +## @item +## Wendy L. Martinez and Angel R. Martinez. @cite{Computational Statistics +## Handbook with MATLAB}. Appendix E, pages 547-557, Chapman & Hall/CRC, +## 2001. +## +## @item +## Athanasios Papoulis. @cite{Probability, Random Variables, and Stochastic +## Processes}. McGraw-Hill, New York, second edition, 1984. +## @end enumerate +## @end deftypefn + +## Author: Arno Onken +## Description: Moments of the normal distribution + +function [mn, v] = normstat (m, s) + + # Check arguments + if (nargin != 2) + print_usage (); + endif + + if (! isempty (m) && ! ismatrix (m)) + error ("normstat: m must be a numeric matrix"); + endif + if (! isempty (s) && ! ismatrix (s)) + error ("normstat: s must be a numeric matrix"); + endif + + if (! isscalar (m) || ! isscalar (s)) + [retval, m, s] = common_size (m, s); + if (retval > 0) + error ("normstat: m and s must be of common size or scalar"); + endif + endif + + # Set moments + mn = m; + v = s .* s; + + # Continue argument check + k = find (! (s > 0) | ! (s < Inf)); + if (any (k)) + mn(k) = NaN; + v(k) = NaN; + endif + +endfunction + +%!test +%! m = 1:6; +%! s = 0.2:0.2:1.2; +%! [mn, v] = normstat (m, s); +%! expected_v = [0.0400, 0.1600, 0.3600, 0.6400, 1.0000, 1.4400]; +%! assert (mn, m); +%! assert (v, expected_v, 0.001); + +%!test +%! s = 0.2:0.2:1.2; +%! [mn, v] = normstat (0, s); +%! expected_mn = [0, 0, 0, 0, 0, 0]; +%! expected_v = [0.0400, 0.1600, 0.3600, 0.6400, 1.0000, 1.4400]; +%! assert (mn, expected_mn, 0.001); +%! assert (v, expected_v, 0.001);