Mercurial > octave-nkf
view scripts/statistics/distributions/normal_cdf.m @ 4960:ce01dbd7e026 ss-2-1-58
[project @ 2004-09-02 03:47:49 by jwe]
author | jwe |
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date | Thu, 02 Sep 2004 03:47:49 +0000 |
parents | 4b0f3b055331 |
children | 4c8a2e4e0717 |
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## Copyright (C) 1995, 1996, 1997 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 2, 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, write to the Free ## Software Foundation, 59 Temple Place - Suite 330, Boston, MA ## 02111-1307, USA. ## -*- texinfo -*- ## @deftypefn {Function File} {} normal_cdf (@var{x}, @var{m}, @var{v}) ## For each element of @var{x}, compute the cumulative distribution ## function (CDF) at @var{x} of the normal distribution with mean ## @var{m} and variance @var{v}. ## ## Default values are @var{m} = 0, @var{v} = 1. ## @end deftypefn ## Author: TT <Teresa.Twaroch@ci.tuwien.ac.at> ## Description: CDF of the normal distribution function cdf = normal_cdf (x, m, v) if (! ((nargin == 1) || (nargin == 3))) usage ("normal_cdf (x, m, v)"); endif if (nargin == 1) m = 0; v = 1; endif if (!isscalar (m) || !isscalar(v)) [retval, x, m, v] = common_size (x, m, v); if (retval > 0) error ("normal_cdf: x, m and v must be of common size or scalar"); endif endif sz = size (x); cdf = zeros (sz); if (isscalar (m) && isscalar(v)) if (find (isinf (m) | isnan (m) | !(v >= 0) | !(v < Inf))) cdf = NaN * ones (sz); else cdf = stdnormal_cdf ((x - m) ./ sqrt (v)); endif else k = find (isinf (m) | isnan (m) | !(v >= 0) | !(v < Inf)); if (any (k)) cdf(k) = NaN; endif k = find (!isinf (m) & !isnan (m) & (v >= 0) & (v < Inf)); if (any (k)) cdf(k) = stdnormal_cdf ((x(k) - m(k)) ./ sqrt (v(k))); endif endif cdf((v == 0) & (x == m)) = 0.5; endfunction