Mercurial > octave-nkf
view scripts/statistics/distributions/wblcdf.m @ 14138:72c96de7a403 stable
maint: update copyright notices for 2012
author | John W. Eaton <jwe@octave.org> |
---|---|
date | Mon, 02 Jan 2012 14:25:41 -0500 |
parents | 19b9f17d22af |
children | f3d52523cde1 |
line wrap: on
line source
## Copyright (C) 2012 Rik Wehbring ## Copyright (C) 1995-2012 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 ## <http://www.gnu.org/licenses/>. ## -*- texinfo -*- ## @deftypefn {Function File} {} wblcdf (@var{x}) ## @deftypefnx {Function File} {} wblcdf (@var{x}, @var{scale}) ## @deftypefnx {Function File} {} wblcdf (@var{x}, @var{scale}, @var{shape}) ## Compute the cumulative distribution function (CDF) at @var{x} of the ## Weibull distribution with scale parameter @var{scale} and shape ## parameter @var{shape}, which is ## @tex ## $$ 1 - e^{-({x \over scale})^{shape}} $$ ## for $x \geq 0$. ## @end tex ## @ifnottex ## ## @example ## 1 - exp (-(x/scale)^shape) ## @end example ## ## @noindent ## for @var{x} @geq{} 0. ## ## Default values are @var{scale} = 1, @var{shape} = 1. ## @end ifnottex ## @end deftypefn ## Author: KH <Kurt.Hornik@wu-wien.ac.at> ## Description: CDF of the Weibull distribution function cdf = wblcdf (x, scale = 1, shape = 1) if (nargin < 1 || nargin > 3) print_usage (); endif if (!isscalar (shape) || !isscalar (scale)) [retval, x, shape, scale] = common_size (x, shape, scale); if (retval > 0) error ("wblcdf: X, SCALE, and SHAPE must be of common size or scalars"); endif endif if (iscomplex (x) || iscomplex (scale) || iscomplex (shape)) error ("wblcdf: X, SCALE, and SHAPE must not be complex"); endif if (isa (x, "single") || isa (scale, "single") || isa (shape, "single")) cdf = NaN (size (x), "single"); else cdf = NaN (size (x)); endif ok = (shape > 0) & (shape < Inf) & (scale > 0) & (scale < Inf); k = (x <= 0) & ok; cdf(k) = 0; k = (x == Inf) & ok; cdf(k) = 1; k = (x > 0) & (x < Inf) & ok; if (isscalar (shape) && isscalar (scale)) cdf(k) = 1 - exp (- (x(k) / scale) .^ shape); else cdf(k) = 1 - exp (- (x(k) ./ scale(k)) .^ shape(k)); endif endfunction %!shared x,y %! x = [-1 0 0.5 1 Inf]; %! y = [0, 1-exp(-x(2:4)), 1]; %!assert(wblcdf (x, ones(1,5), ones(1,5)), y); %!assert(wblcdf (x, 1, ones(1,5)), y); %!assert(wblcdf (x, ones(1,5), 1), y); %!assert(wblcdf (x, [0 1 NaN Inf 1], 1), [NaN 0 NaN NaN 1]); %!assert(wblcdf (x, 1, [0 1 NaN Inf 1]), [NaN 0 NaN NaN 1]); %!assert(wblcdf ([x(1:2) NaN x(4:5)], 1, 1), [y(1:2) NaN y(4:5)]); %% Test class of input preserved %!assert(wblcdf ([x, NaN], 1, 1), [y, NaN]); %!assert(wblcdf (single([x, NaN]), 1, 1), single([y, NaN])); %!assert(wblcdf ([x, NaN], single(1), 1), single([y, NaN])); %!assert(wblcdf ([x, NaN], 1, single(1)), single([y, NaN])); %% Test input validation %!error wblcdf () %!error wblcdf (1,2,3,4) %!error wblcdf (ones(3),ones(2),ones(2)) %!error wblcdf (ones(2),ones(3),ones(2)) %!error wblcdf (ones(2),ones(2),ones(3)) %!error wblcdf (i, 2, 2) %!error wblcdf (2, i, 2) %!error wblcdf (2, 2, i)