dynare/matlab/lpdfbeta.m

24 lines
630 B
Matlab

function ldens = lpdfbeta(x,a,b);
% function ldens = lpdfbeta(x,a,b)
% log Beta PDF
%
% INPUTS
% x: density evatuated at x
% a: Beta distribution paramerer
% b: Beta distribution paramerer
%
% OUTPUTS
% ldens: the log Beta PDF
%
% SPECIAL REQUIREMENTS
% none
%
% part of DYNARE, copyright Dynare Team (2003-2008)
% Gnu Public License.
ldens = gammaln(a+b) - gammaln(a) - gammaln(b) + (a-1)*log(x) + (b-1)*log(1-x);
% 10/11/03 MJ adapted from a GAUSS version by F. Schorfheide, translated
% to Matlab by R. Wouters.
% use Matlab gammaln instead of lngam