2005-02-18 20:54:39 +01:00
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function ldens = lpdfgam(x,a,b);
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2008-01-11 16:42:27 +01:00
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2008-01-11 16:46:23 +01:00
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% function ldens = lpdfgam(x,a,b)
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2008-01-11 16:42:27 +01:00
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% log GAMMA PDF
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%
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% INPUTS
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% x: density evatuated at x
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% a: GAMMA distribution paramerer
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% b: GAMMA distribution paramerer
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%
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% OUTPUTS
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% ldens: the log GAMMA PDF
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%
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% SPECIAL REQUIREMENTS
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% none
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%
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% part of DYNARE, copyright Dynare Team (2003-2008)
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% Gnu Public License.
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2005-02-18 20:54:39 +01:00
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ldens = -gammaln(a) -a*log(b)+ (a-1)*log(x) -x/b ;
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% 10/11/03 MJ adapted from an earlier GAUSS version by F. Schorfeide,
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% translated to MATLAB by R. Wouters
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% use MATLAB gammaln rather than lngam
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