comparison toolboxes/FullBNT-1.0.7/bnt/CPDs/@tabular_CPD/Old/sample_node_single_case.m @ 0:e9a9cd732c1e tip

first hg version after svn

+function y = sample_node(CPD, pev)
+% SAMPLE_NODE Draw a random sample from P(Xi | x(pi_i), theta_i)  (tabular)
+% y = sample_node(CPD, pev)
+%
+% pev{i} is the value of the i'th parent (if any)
+
+%assert(~any(isemptycell(pev)));
+
+%CPT = CPD_to_CPT(CPD);
+%sz = mysize(CPT);
+sz = CPD.sizes; 
+nparents = length(sz)-1;
+if nparents > 0
+  pvals = cat(1, pev{:});
+end
+switch nparents
+ case 0, T = CPD.CPT;
+ case 1, T = CPD.CPT(pvals(1), :);
+ case 2, T = CPD.CPT(pvals(1), pvals(2), :);
+ case 3, T = CPD.CPT(pvals(1), pvals(2), pvals(3), :);
+ case 4, T = CPD.CPT(pvals(1), pvals(2), pvals(3), pvals(4), :);
+ otherwise,
+  psz = sz(1:end-1);
+  ssz = sz(end);
+  i = subv2ind(psz, pvals(:)');
+  T = reshape(CPD.CPT, [prod(psz) ssz]);
+  T = T(i,:);
+end
+
+if sz(end)==2
+  r = rand(1,1);
+  if r > T(1)
+    y = 2;
+  else
+    y = 1;
+  end
+else
+  y = sample_discrete(T);
+end