Daniel@0: function [post, a] = mdnpost(mixparams, t)
Daniel@0: %MDNPOST Computes the posterior probability for each MDN mixture component.
Daniel@0: %
Daniel@0: %	Description
Daniel@0: %	POST = MDNPOST(MIXPARAMS, T) computes the posterior probability
Daniel@0: %	P(J|T) of each data vector in T under the Gaussian mixture model
Daniel@0: %	represented by the corresponding entries in MIXPARAMS. Each row of T
Daniel@0: %	represents a single vector.
Daniel@0: %
Daniel@0: %	[POST, A] = MDNPOST(MIXPARAMS, T) also computes the activations A
Daniel@0: %	(i.e. the probability P(T|J) of the data conditioned on each
Daniel@0: %	component density) for a Gaussian mixture model.
Daniel@0: %
Daniel@0: %	See also
Daniel@0: %	MDNGRAD, MDNPROB
Daniel@0: %
Daniel@0: 
Daniel@0: %	Copyright (c) Ian T Nabney (1996-2001)
Daniel@0: %	David J Evans (1998)
Daniel@0: 
Daniel@0: [prob a] = mdnprob(mixparams, t);
Daniel@0: 
Daniel@0: s = sum(prob, 2);
Daniel@0: % Set any zeros to one before dividing
Daniel@0: s = s + (s==0);
Daniel@0: post = prob./(s*ones(1, mixparams.ncentres));