comparison toolboxes/FullBNT-1.0.7/bnt/general/sample_bnet.m @ 0:e9a9cd732c1e tip

first hg version after svn

+function sample = sample_bnet(bnet, varargin)
+% SAMPLE_BNET Generate a random sample from a Bayes net.
+% SAMPLE = SAMPLE_BNET(BNET, ...)
+%
+% sample{i} contains the value of the i'th node.
+% i.e., the result is an Nx1 cell array.
+% Nodes are sampled in the order given by bnet.order.
+%
+% Optional arguments:
+%
+% evidence - initial evidence; if evidence{i} is non-empty, node i won't be sampled.
+
+% set defauly params
+n = length(bnet.dag);
+sample = cell(n,1);
+
+% get optional params
+args = varargin;
+nargs = length(args);
+for i=1:2:nargs
+  switch args{i},
+   case 'evidence',    sample = args{i+1}(:);
+   otherwise, error(['unrecognized argument ' args{i}])
+  end
+end
+
+for j=bnet.order(:)'
+  if isempty(sample{j})
+    %ps = parents(bnet.dag, j);
+    ps = bnet.parents{j};
+    e = bnet.equiv_class(j);
+    sample{j} = sample_node(bnet.CPD{e}, sample(ps));
+  end
+end