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dgamma

PURPOSE

DGAMMA The gamma density function

SYNOPSIS

function f = dgamma(x,a,b)

DESCRIPTION

DGAMMA   The gamma density function

         f = dgamma(x,a)

CROSS-REFERENCE INFORMATION

This function calls:

This function is called by:

qgamma QGAMMA The gamma inverse distribution function

SOURCE CODE

0001 function f = dgamma(x,a,b)
0002 %DGAMMA   The gamma density function
0003 %
0004 %         f = dgamma(x,a)
0005 
0006 %       Anders Holtsberg, 18-11-93
0007 %       Copyright (c) Anders Holtsberg
0008 
0009 if any(any(a<=0))
0010    error('Parameter a is wrong')
0011 end
0012 
0013 f = (x./b) .^ (a-1) .* exp(-x./b) ./ (b.*gamma(a));
0014 I0 = find(x<0);
0015 f(I0) = zeros(size(I0));