wolffd@0: function bnet = fgraph_to_bnet(fg) wolffd@0: % FGRAPH_TO_BNET Convert a factor graph to a Bayes net wolffd@0: % bnet = fgraph_to_bnet(fg) wolffd@0: % wolffd@0: % We assume all factors are tabular_CPD. wolffd@0: % We create 1 dummy observed node for every factor. wolffd@0: wolffd@0: N = fg.nvars + fg.nfactors; wolffd@0: vnodes = 1:fg.nvars; wolffd@0: fnodes = fg.nvars+1:N; wolffd@0: dag = zeros(N); wolffd@0: for x=1:fg.nvars wolffd@0: dag(x, fnodes(fg.dep{x})) = 1; wolffd@0: end wolffd@0: ns = [fg.node_sizes ones(1, fg.nfactors)]; wolffd@0: discrete = [fg.dnodes fnodes]; wolffd@0: bnet = mk_bnet(dag, ns, 'discrete', discrete); wolffd@0: for x=1:fg.nvars wolffd@0: bnet.CPD{x} = tabular_CPD(bnet, x, 'CPT', 'unif'); wolffd@0: end wolffd@0: ev = cell(1, fg.nvars); % no evidence wolffd@0: for i=1:fg.nfactors wolffd@0: f = fnodes(i); wolffd@0: e = fg.equiv_class(i); wolffd@0: pot = convert_to_pot(fg.factors{e}, 'd', fg.dom{i}, ev); wolffd@0: m = pot_to_marginal(pot); wolffd@0: bnet.CPD{f} = tabular_CPD(bnet, f, 'CPT', m.T); wolffd@0: end wolffd@0: wolffd@0: