diff toolboxes/FullBNT-1.0.7/bnt/potentials/check_for_cd_arcs.m @ 0:e9a9cd732c1e tip

first hg version after svn

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/bnt/potentials/check_for_cd_arcs.m	Tue Feb 10 15:05:51 2015 +0000
@@ -0,0 +1,23 @@
+function check_for_cd_arcs(onodes, cnodes, dag)
+% CHECK_FOR_CD_ARCS Raise an error if there are any C->D links where the C node is hidden.
+% check_for_cd_arcs(onodes, cnodes, dag)
+%
+% We cannot convert the logistic/softmax function (C->D CPD) to a Gaussian potential
+% unless we use the variational approximation discussed in 
+% "A variational approximation for Bayesian networks with discrete and continuous latent
+% variables", K. Murphy, UAI 1999.
+
+n = length(dag);
+hnodes = mysetdiff(1:n, onodes);
+chid = myintersect(cnodes, hnodes);
+dnodes = mysetdiff(1:n, cnodes);
+for i=chid(:)'
+  dcs = myintersect(children(dag, i), dnodes);
+  if ~isempty(dcs)
+    error(['hidden cts node ' num2str(i) ' has a discrete child']);
+  end
+end
+
+
+
+