## Copyright (C) 1996, 1997 John W. Eaton
##
## 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 2, 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, write to the Free
## Software Foundation, 59 Temple Place - Suite 330, Boston, MA
## 02111-1307, USA.

## usage: beta (a, b)
##
## Returns the beta function beta(a,b) = gamma(a) * gamma(b) / gamma(a+b)
## of a and b.

## Author: KH <Kurt.Hornik@ci.tuwien.ac.at>
## Created: 13 June 1993
## Adapted-By: jwe

function retval = beta (a, b)

  if (nargin != 2)
    usage ("beta (a, b)");
  endif

  retval = exp (lgamma (a) + lgamma (b) - lgamma (a+b));

endfunction