comparison toolboxes/FullBNT-1.0.7/bnt/CPDs/@discrete_CPD/sample_node.m @ 0:e9a9cd732c1e tip

first hg version after svn

+function y = sample_node(CPD, pvals)
+% SAMPLE_NODE Draw a random sample from P(Xi | x(pi_i), theta_i)  (discrete)
+% y = sample_node(CPD, parent_evidence)
+%
+% parent_evidence{i} is the value of the i'th parent
+
+if 0
+n = length(pvals)+1;
+dom = 1:n;
+evidence = cell(1,n);
+evidence(1:n-1) = pvals;
+T = convert_to_table(CPD, dom, evidence);
+y = sample_discrete(T);
+end
+
+
+CPT = CPD_to_CPT(CPD);
+sz = mysize(CPT);
+nparents = length(sz)-1;
+switch nparents
+ case 0, T = CPT;
+ case 1, T = CPT(pvals{1}, :);
+ case 2, T = CPT(pvals{1}, pvals{2}, :);
+ case 3, T = CPT(pvals{1}, pvals{2}, pvals{3}, :);
+ case 4, T = CPT(pvals{1}, pvals{2}, pvals{3}, pvals{4}, :);
+ otherwise,
+  pvals = cat(1, pvals{:});
+  psz = sz(1:end-1);
+  ssz = sz(end);
+  i = subv2ind(psz, pvals(:)');
+  T = reshape(CPT, [prod(psz) ssz]);
+  T = T(i,:);
+end
+y = sample_discrete(T);