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

first hg version after svn

+function fullm = add_evidence_to_gmarginal(fmarginal, evidence, ns, cnodes)
+% ADD_EVIDENCE_TO_GMARGINAL 'pump up' observed nodes back to their original size.
+% function fullm = add_evidence_to_gmarginal(fmarginal, evidence, ns, cnodes)
+%
+% We introduce 0s into the array in positions which are incompatible with the evidence.
+% for both discrete and continuous nodes.
+%
+% See also add_ev_to_dmarginal
+
+dom = fmarginal.domain;
+fullm.domain = fmarginal.domain;
+
+% Find out which values of the discrete parents (if any) are compatible with 
+% the discrete evidence (if any).
+dnodes = mysetdiff(1:length(ns), cnodes);
+ddom = myintersect(dom, dnodes);
+cdom = myintersect(dom, cnodes);
+odom = dom(~isemptycell(evidence(dom)));
+hdom = dom(isemptycell(evidence(dom)));
+
+% Find the entries in the big table that are compatible with the discrete evidence.
+% (We will put the probabilities from the small inferred table into these positions.)
+% We could use add_ev_to_dmarginal to do this.
+dobs = myintersect(ddom, odom);
+dvals = cat(1, evidence{dobs});
+ens = ns; % effective node sizes
+ens(dobs) = 1;
+S = prod(ens(ddom));
+subs = ind2subv(ens(ddom), 1:S);
+mask = find_equiv_posns(dobs, ddom);
+%subs(mask) = dvals; % bug fix by P. Brutti
+for i=1:length(mask),
+  subs(:,mask(i)) = dvals(i);
+end       
+supportedQs = subv2ind(ns(ddom), subs);
+
+if isempty(ddom)
+  Qarity = 1;
+else
+  Qarity = prod(ns(ddom));
+end
+fullm.T = zeros(Qarity, 1);
+fullm.T(supportedQs) = fmarginal.T(:);
+fullm.T = myreshape(fullm.T, ns(ddom));
+
+
+if isempty(cdom)
+  fullm.mu = [];
+  fullm.sigma = [];
+  return;
+end
+
+% Now put the hidden cts parts into their right blocks,
+% leaving the observed cts parts as 0.
+cobs = myintersect(cdom, odom);
+chid = myintersect(cdom, hdom);
+cvals = cat(1, evidence{cobs});
+n = sum(ns(cdom));
+fullm.mu = zeros(n,Qarity);
+fullm.Sigma = zeros(n,n,Qarity);
+
+if ~isempty(chid)
+  chid_blocks = block(find_equiv_posns(chid, cdom), ns(cdom));
+end
+if ~isempty(cobs)
+  cobs_blocks = block(find_equiv_posns(cobs, cdom), ns(cdom));
+end
+
+for i=1:length(supportedQs)
+  Q = supportedQs(i);
+  if ~isempty(chid)
+    fullm.mu(chid_blocks, Q) = fmarginal.mu(:, i);
+    fullm.Sigma(chid_blocks, chid_blocks, Q) = fmarginal.Sigma(:,:,i);
+  end
+  if ~isempty(cobs)
+    fullm.mu(cobs_blocks, Q) = cvals(:);
+  end
+end