Generation of Random Variates
09 Feb 2012
generates random variates from over 870 univariate distributions
function y = betaln(z,w)
%BETALN Logarithm of beta function.
% Y = BETALN(Z,W) computes the natural logarithm of the beta
% function for corresponding elements of Z and W. The arrays Z and
% W must be the same size (or either can be scalar). BETALN is
% defined as:
% BETALN = LOG(BETA(Z,W))
% and is obtained without computing BETA(Z,W). Since the beta
% function can range over very large or very small values, its
% logarithm is sometimes more useful.
% See also BETAINC, BETA.
% Reference: Abramowitz & Stegun, sec. 6.2.
% Copyright 1984-2002 The MathWorks, Inc.
% $Revision: 5.8 $ $Date: 2002/04/09 00:29:46 $
y = gammaln(z)+gammaln(w)-gammaln(z+w);