X-Git-Url: https://git.creatis.insa-lyon.fr/pubgit/?a=blobdiff_plain;f=octave_packages%2Fm%2Fstatistics%2Fdistributions%2Fhygernd.m;fp=octave_packages%2Fm%2Fstatistics%2Fdistributions%2Fhygernd.m;h=0fc167b126e3d3704f5494438b506e55d0be6167;hb=1c0469ada9531828709108a4882a751d2816994a;hp=0000000000000000000000000000000000000000;hpb=63de9f36673d49121015e3695f2c336ea92bc278;p=CreaPhase.git diff --git a/octave_packages/m/statistics/distributions/hygernd.m b/octave_packages/m/statistics/distributions/hygernd.m new file mode 100644 index 0000000..0fc167b --- /dev/null +++ b/octave_packages/m/statistics/distributions/hygernd.m @@ -0,0 +1,148 @@ +## Copyright (C) 2012 Rik Wehbring +## Copyright (C) 1997-2012 Kurt Hornik +## +## 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 +## . + +## -*- texinfo -*- +## @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 be positive integers +## with @var{m} and @var{n} not greater than @var{t}. +## +## 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, varargin) + + 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 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 + 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 + rnd = NaN (sz, cls); + endif + else + rnd = NaN (sz, cls); + rn = rand (sz); + 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 + 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) +