spm_lg_gamma.m
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			function [lng] = spm_lg_gamma(p,b)
			% Log of generalised gamma function
			% FORMAT [lng] = spm_lg_gamma(p,b)
			%
			% p - dimension parameter
			% b - degrees of freedom type parameter
			%__________________________________________________________________________
			%
			% References:
			% * Bayesian Inference in Statistical Analysis, Box & Tiao, 1992, p. 427.
			% * Aspects of Multivariate Statistical Theory, R.J. Muirhead, p. 62.
			%__________________________________________________________________________
			% Copyright (C) 2008 Wellcome Trust Centre for Neuroimaging

			% Will Penny
			% $Id: spm_lg_gamma.m 2784 2009-02-24 19:11:20Z guillaume $

			if b <= (p-1)/2
			warning('Parameter out of range');
			lng = NaN;
			return
			end

			lng = (p(p-1)/2) gammaln(0.5);
			for alpha = 1:p
			lng = lng + gammaln(b+0.5*(alpha-1));
			end

Slepi/Code/Utilities/spm12/spm_lg_gamma.m8a186cd82567master