annotate toolboxes/FullBNT-1.0.7/bnt/CPDs/@discrete_CPD/Old/prob_CPD.m @ 0:e9a9cd732c1e tip

first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
parents
children
rev   line source
wolffd@0 1 function p = prob_CPD(CPD, domain, ns, cnodes, evidence)
wolffd@0 2 % PROB_CPD Compute prob of a node given evidence on the parents (discrete)
wolffd@0 3 % p = prob_CPD(CPD, domain, ns, cnodes, evidence)
wolffd@0 4 %
wolffd@0 5 % domain is the domain of CPD.
wolffd@0 6 % node_sizes(i) is the size of node i.
wolffd@0 7 % cnodes = all the cts nodes
wolffd@0 8 % evidence{i} is the evidence on the i'th node.
wolffd@0 9
wolffd@0 10 ps = domain(1:end-1);
wolffd@0 11 self = domain(end);
wolffd@0 12 CPT = CPD_to_CPT(CPD);
wolffd@0 13
wolffd@0 14 if isempty(ps)
wolffd@0 15 T = CPT;
wolffd@0 16 else
wolffd@0 17 assert(~any(isemptycell(evidence(ps))));
wolffd@0 18 pvals = cat(1, evidence{ps});
wolffd@0 19 i = subv2ind(ns(ps), pvals(:)');
wolffd@0 20 T = reshape(CPT, [prod(ns(ps)) ns(self)]);
wolffd@0 21 T = T(i,:);
wolffd@0 22 end
wolffd@0 23 p = T(evidence{self});
wolffd@0 24
wolffd@0 25