annotate toolboxes/FullBNT-1.0.7/bnt/CPDs/@gaussian_CPD/sample_node.m @ 0:cc4b1211e677 tip

initial commit to HG from Changeset: 646 (e263d8a21543) added further path and more save "camirversion.m"
author Daniel Wolff
date Fri, 19 Aug 2016 13:07:06 +0200
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Daniel@0 1 function y = sample_node(CPD, pev)
Daniel@0 2 % SAMPLE_NODE Draw a random sample from P(Xi | x(pi_i), theta_i) (gaussian)
Daniel@0 3 % y = sample_node(CPD, parent_evidence)
Daniel@0 4 %
Daniel@0 5 % pev{i} is the value of the i'th parent (if there are any parents)
Daniel@0 6 % y is the sampled value (a scalar or vector)
Daniel@0 7
Daniel@0 8 if length(CPD.dps)==0
Daniel@0 9 i = 1;
Daniel@0 10 else
Daniel@0 11 dpvals = cat(1, pev{CPD.dps});
Daniel@0 12 i = subv2ind(CPD.sizes(CPD.dps), dpvals(:)');
Daniel@0 13 end
Daniel@0 14
Daniel@0 15 if length(CPD.cps) == 0
Daniel@0 16 y = gsamp(CPD.mean(:,i), CPD.cov(:,:,i), 1);
Daniel@0 17 else
Daniel@0 18 pev = pev(:);
Daniel@0 19 x = cat(1, pev{CPD.cps});
Daniel@0 20 y = gsamp(CPD.mean(:,i) + CPD.weights(:,:,i)*x(:), CPD.cov(:,:,i), 1);
Daniel@0 21 end
Daniel@0 22 y = y(:);