comparison toolboxes/FullBNT-1.0.7/bnt/CPDs/@hhmm2Q_CPD/CPD_to_CPT.m @ 0:e9a9cd732c1e tip

first hg version after svn

+function CPT = CPD_to_CPT(CPD)
+% Compute the big CPT for an HHMM Q node (including F parents)
+% by combining internal transprob and startprob
+% function CPT = CPD_to_CPT(CPD)
+
+Qsz = CPD.Qsz;
+
+if ~isempty(CPD.Fbelow_ndx)
+  if ~isempty(CPD.Fself_ndx) % general case
+    error('not implemented')
+  else % no F from self, hence no startprob (top level)
+    nps = length(CPD.dom_sz)-1; % num parents
+    CPT = 0*myones(CPD.dom_sz);
+    % when Fself=1, the CPT(i,j) = delta(i,j) for all k
+    for k=1:prod(CPD.Qpsizes)
+      Qps_vals = ind2subv(CPD.Qpsizes, k);
+      ndx = mk_multi_index(nps+1, [CPD.Fbelow_ndx CPD.Qps_ndx], [1 Qps_vals]);
+      CPT(ndx{:}) = eye(Qsz); % CPT(:,2,k,:) or CPT(:,k,2,:) etc
+    end
+    ndx = mk_multi_index(nps+1, CPD.Fbelow_ndx, 2);
+    CPT(ndx{:}) = CPD.transprob; % we assume transprob is in topo order
+  end
+else % no F signal from below
+  if ~isempty(CPD.Fself_ndx) % bottom level
+    nps = length(CPD.dom_sz)-1; % num parents
+    CPT = 0*myones(CPD.dom_sz);
+    ndx = mk_multi_index(nps+1, CPD.Fself_ndx, 1);
+    CPT(ndx{:}) = CPD.transprob;
+    ndx = mk_multi_index(nps+1, CPD.Fself_ndx, 2);
+    CPT(ndx{:}) = CPD.startprob;
+  else % no F from self
+    error('An hhmmQ node without any F parents is just a tabular_CPD')
+  end
+end
+