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

first hg version after svn
author wolffd
date Tue, 10 Feb 2015 15:05:51 +0000
parents
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--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/toolboxes/FullBNT-1.0.7/bnt/CPDs/@discrete_CPD/CPD_to_lambda_msg.m	Tue Feb 10 15:05:51 2015 +0000
@@ -0,0 +1,16 @@
+function lam_msg = CPD_to_lambda_msg(CPD, msg_type, n, ps, msg, p, evidence)
+% CPD_TO_LAMBDA_MSG Compute lambda message (discrete)
+% lam_msg = compute_lambda_msg(CPD, msg_type, n, ps, msg, p, evidence)
+% Pearl p183 eq 4.52
+
+switch msg_type
+  case 'd',
+   T = prod_CPT_and_pi_msgs(CPD, n, ps, msg, p);
+   mysize = length(msg{n}.lambda);
+   lambda = dpot(n, mysize, msg{n}.lambda);
+   T = multiply_by_pot(T, lambda);
+   lam_msg = pot_to_marginal(marginalize_pot(T, p));
+   lam_msg = lam_msg.T;           
+ case 'g',
+  error('discrete_CPD can''t create Gaussian msgs')
+end