Mercurial > octave
view scripts/statistics/distributions/expcdf.m @ 11469:c776f063fefe
Overhaul m-script files to use common variable name between code and documentation.
author | Rik <octave@nomad.inbox5.com> |
---|---|
date | Sun, 09 Jan 2011 12:41:21 -0800 |
parents | eb63fbe60fab |
children | 1740012184f9 |
line wrap: on
line source
## Copyright (C) 1995, 1996, 1997, 2005, 2006, 2007, 2008 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} {} expcdf (@var{x}, @var{lambda}) ## For each element of @var{x}, compute the cumulative distribution ## function (CDF) at @var{x} of the exponential distribution with ## mean @var{lambda}. ## ## The arguments can be of common size or scalar. ## @end deftypefn ## Author: KH <Kurt.Hornik@wu-wien.ac.at> ## Description: CDF of the exponential distribution function cdf = expcdf (x, lambda) if (nargin != 2) print_usage (); endif if (!isscalar (x) && !isscalar(lambda)) [retval, x, lambda] = common_size (x, lambda); if (retval > 0) error ("expcdf: x and lambda must be of common size or scalar"); endif endif if (isscalar (x)) sz = size (lambda); else sz = size (x); endif cdf = zeros (sz); k = find (isnan (x) | !(lambda > 0)); if (any (k)) cdf(k) = NaN; endif k = find ((x == Inf) & (lambda > 0)); if (any (k)) cdf(k) = 1; endif k = find ((x > 0) & (x < Inf) & (lambda > 0)); if (any (k)) if isscalar (lambda) cdf (k) = 1 - exp (- x(k) ./ lambda); elseif isscalar (x) cdf (k) = 1 - exp (- x ./ lambda(k)); else cdf (k) = 1 - exp (- x(k) ./ lambda(k)); endif endif endfunction