Mercurial > octave-nkf
view scripts/statistics/distributions/lognrnd.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} {} lognrnd (@var{mu}, @var{sigma}) ## @deftypefnx {Function File} {} lognrnd (@var{mu}, @var{sigma}, @var{r}) ## @deftypefnx {Function File} {} lognrnd (@var{mu}, @var{sigma}, @var{r}, @var{c}, @dots{}) ## @deftypefnx {Function File} {} lognrnd (@var{mu}, @var{sigma}, [@var{sz}]) ## Return a matrix of random samples from the lognormal distribution with ## parameters @var{mu} and @var{sigma}. ## ## 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{mu} and @var{sigma}. ## @end deftypefn ## Author: KH <Kurt.Hornik@wu-wien.ac.at> ## Description: Random deviates from the log normal distribution function rnd = lognrnd (mu, sigma, varargin) if (nargin < 2) print_usage (); endif if (!isscalar (mu) || !isscalar (sigma)) [retval, mu, sigma] = common_size (mu, sigma); if (retval > 0) error ("lognrnd: MU and SIGMA must be of common size or scalars"); endif endif if (iscomplex (mu) || iscomplex (sigma)) error ("lognrnd: MU and SIGMA must not be complex"); endif if (nargin == 2) sz = size (mu); elseif (nargin == 3) 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 ("lognrnd: dimension vector must be row vector of non-negative integers"); endif elseif (nargin > 3) if (any (cellfun (@(x) (!isscalar (x) || x < 0), varargin))) error ("lognrnd: dimensions must be non-negative integers"); endif sz = [varargin{:}]; endif if (!isscalar (mu) && !isequal (size (mu), sz)) error ("lognrnd: MU and SIGMA must be scalar or of size SZ"); endif if (isa (mu, "single") || isa (sigma, "single")) cls = "single"; else cls = "double"; endif if (isscalar (mu) && isscalar (sigma)) if ((sigma > 0) && (sigma < Inf)) rnd = exp (mu + sigma * randn (sz)); else rnd = NaN (sz, cls); endif else rnd = exp (mu + sigma .* randn (sz)); k = (sigma < 0) | (sigma == Inf); rnd(k) = NaN; endif endfunction %!assert(size (lognrnd (1,2)), [1, 1]); %!assert(size (lognrnd (ones(2,1), 2)), [2, 1]); %!assert(size (lognrnd (ones(2,2), 2)), [2, 2]); %!assert(size (lognrnd (1, 2*ones(2,1))), [2, 1]); %!assert(size (lognrnd (1, 2*ones(2,2))), [2, 2]); %!assert(size (lognrnd (1, 2, 3)), [3, 3]); %!assert(size (lognrnd (1, 2, [4 1])), [4, 1]); %!assert(size (lognrnd (1, 2, 4, 1)), [4, 1]); %% Test class of input preserved %!assert(class (lognrnd (1, 2)), "double"); %!assert(class (lognrnd (single(1), 2)), "single"); %!assert(class (lognrnd (single([1 1]), 2)), "single"); %!assert(class (lognrnd (1, single(2))), "single"); %!assert(class (lognrnd (1, single([2 2]))), "single"); %% Test input validation %!error lognrnd () %!error lognrnd (1) %!error lognrnd (ones(3),ones(2)) %!error lognrnd (ones(2),ones(3)) %!error lognrnd (i, 2) %!error lognrnd (2, i) %!error lognrnd (1,2, -1) %!error lognrnd (1,2, ones(2)) %!error lognrnd (1, 2, [2 -1 2]) %!error lognrnd (1,2, 1, ones(2)) %!error lognrnd (1,2, 1, -1) %!error lognrnd (ones(2,2), 2, 3) %!error lognrnd (ones(2,2), 2, [3, 2]) %!error lognrnd (ones(2,2), 2, 2, 3)