Generation of Random Variates
09 Feb 2012
generates random variates from over 870 univariate distributions
function p = factorial(n)
%FACTORIAL Factorial function.
% FACTORIAL(N) is the product of all the integers from 1 to N,
% i.e. prod(1:N). Since double precision numbers only have about
% 15 digits, the answer is only accurate for N <= 21. For larger N,
% the answer will have the right magnitude, and is accurate for
% the first 15 digits.
% See also PROD.
% Copyright 1984-2000 The MathWorks, Inc.
% $Revision: 1.4 $
if (length(n)~=1) | (fix(n) ~= n) | (n < 0)
error('N must be a positive integer');
p = prod(1:n);