diff toolboxes/FullBNT-1.0.7/bnt/CPDs/@discrete_CPD/Old/prob_node.m @ 0:e9a9cd732c1e tip

first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
parents
children
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/bnt/CPDs/@discrete_CPD/Old/prob_node.m	Tue Feb 10 15:05:51 2015 +0000
@@ -0,0 +1,51 @@
+function [P, p] = prob_node(CPD, self_ev, pev)
+% PROB_NODE Compute prod_m P(x(i,m)| x(pi_i,m), theta_i) for node i (discrete)
+% [P, p] = prob_node(CPD, self_ev, pev)
+%
+% self_ev(m) is the evidence on this node in case m.
+% pev(i,m) is the evidence on the i'th parent in case m (if there are any parents).
+% (These may also be cell arrays.)
+%
+% p(m) = P(x(i,m)| x(pi_i,m), theta_i) 
+% P = prod p(m)
+
+if iscell(self_ev), usecell = 1; else usecell = 0; end
+
+ncases = length(self_ev);
+sz = dom_sizes(CPD);
+
+nparents = length(sz)-1;
+if nparents == 0
+  assert(isempty(pev));
+else
+  assert(isequal(size(pev), [nparents ncases]));
+end
+
+n = length(sz);
+dom = 1:n;
+p = zeros(1, ncases);
+if nparents == 0
+  for m=1:ncases
+    if usecell
+      evidence = {self_ev{m}};
+    else
+      evidence = num2cell(self_ev(m));
+    end
+    T = convert_to_table(CPD, dom, evidence);
+    p(m) = T;
+  end
+else
+  for m=1:ncases
+    if usecell
+      evidence = cell(1,n);
+      evidence(1:n-1) = pev(:,m);
+      evidence(n) = self_ev(m);
+    else
+      evidence = num2cell([pev(:,m)', self_ev(m)]);
+    end
+    T = convert_to_table(CPD, dom, evidence);
+    p(m) = T;
+  end
+end
+P = prod(p);
+