wolffd@0: function [m, pot] = marginal_family(engine, query)
wolffd@0: % MARGINAL_NODES Compute the marginal on the family of the specified node (jtree_limid)
wolffd@0: % [m, pot] = marginal_family(engine, query)
wolffd@0: %
wolffd@0: % query should be a single decision node
wolffd@0: 
wolffd@0: bnet = bnet_from_engine(engine);
wolffd@0: d = query;
wolffd@0: assert(myismember(d, bnet.decision_nodes));
wolffd@0: fam = family(bnet.dag, d);
wolffd@0: 
wolffd@0: clpot = init_clpot(bnet, engine.cliques, engine.clq_ass_to_node, engine.evidence, engine.exclude);
wolffd@0: 
wolffd@0: % collect to root (clique containing d) 
wolffd@0: C = length(engine.cliques);
wolffd@0: seppot = cell(C, C);    % separators are implicitely initialized to 1s
wolffd@0: for n=engine.postorder{d}(1:end-1)
wolffd@0:   for p=parents(engine.rooted_jtree{d}, n)
wolffd@0:     %clpot{p} = divide_by_pot(clpot{n}, seppot{p,n}); % dividing by 1 is redundant
wolffd@0:     seppot{p,n} = marginalize_pot(clpot{n}, engine.separator{p,n});
wolffd@0:     clpot{p} = multiply_by_pot(clpot{p}, seppot{p,n});
wolffd@0:   end
wolffd@0: end
wolffd@0: 
wolffd@0: root = engine.clq_ass_to_node(d);
wolffd@0: assert(root == engine.postorder{d}(end));
wolffd@0: pot = marginalize_pot(clpot{root}, fam);
wolffd@0: m = pot_to_marginal(pot);
wolffd@0: 
wolffd@0: %%%%%%%%%%%
wolffd@0: 
wolffd@0: 
wolffd@0: function clpot = init_clpot(bnet, cliques, clq_ass_to_node, evidence, exclude)
wolffd@0: 
wolffd@0: % Set the clique potentials to all 1s
wolffd@0: C = length(cliques);
wolffd@0: clpot = cell(1, C);
wolffd@0: ns = bnet.node_sizes;
wolffd@0: for i=1:C
wolffd@0:   clpot{i} = upot(cliques{i}, ns(cliques{i}));
wolffd@0: end
wolffd@0: 
wolffd@0: N = length(bnet.dag);
wolffd@0: nodes = mysetdiff(1:N, exclude);
wolffd@0: 
wolffd@0: for n=nodes(:)'
wolffd@0:   fam = family(bnet.dag, n);
wolffd@0:   e = bnet.equiv_class(n);
wolffd@0:   c = clq_ass_to_node(n);
wolffd@0:   pot = convert_to_pot(bnet.CPD{e}, 'u', fam(:), evidence);
wolffd@0:   clpot{c} = multiply_by_pot(clpot{c}, pot);
wolffd@0: end