Mercurial > hg > camir-aes2014
diff toolboxes/FullBNT-1.0.7/bnt/inference/static/@cond_gauss_inf_engine/enter_evidence.m @ 0:e9a9cd732c1e tip
first hg version after svn
author | wolffd |
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date | Tue, 10 Feb 2015 15:05:51 +0000 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/toolboxes/FullBNT-1.0.7/bnt/inference/static/@cond_gauss_inf_engine/enter_evidence.m Tue Feb 10 15:05:51 2015 +0000 @@ -0,0 +1,57 @@ +function [engine, loglik] = enter_evidence(engine, evidence, varargin) +% ENTER_EVIDENCE Add the specified evidence to the network (cond_gauss) +% [engine, loglik] = enter_evidence(engine, evidence, ...) +% +% evidence{i} = [] if if X(i) is hidden, and otherwise contains its observed value (scalar or column vector) + +bnet = bnet_from_engine(engine); +ns = bnet.node_sizes(:); +observed = ~isemptycell(evidence); +onodes = find(observed); +hnodes = find(isemptycell(evidence)); +engine.evidence = evidence; + +% check there are no C->D links where C is hidden +pot_type = determine_pot_type(bnet, onodes); + +dhid = myintersect(hnodes, bnet.dnodes); +S = prod(ns(dhid)); +T = zeros(S,1); + +N = length(bnet.dag); +mu = cell(1,N); +Sigma = cell(1,N); +cobs = myintersect(bnet.cnodes, onodes); +chid = myintersect(bnet.cnodes, hnodes); +ens = ns; +ens(cobs) = 0; +for j=chid(:)' + mu{j} = zeros(ens(j), S); + Sigma{j} = zeros(ens(j), ens(j), S); +end + +for i=1:S + dvals = ind2subv(ns(dhid), i); + evidence(dhid) = num2cell(dvals); + [sub_engine, loglik] = enter_evidence(engine.sub_engine, evidence); + for j=chid(:)' + m = marginal_nodes(sub_engine, j); + mu{j}(:,i) = m.mu; + Sigma{j}(:,:,i) = m.Sigma; + end + T(i) = exp(loglik); +end + +[T, lik] = normalise(T); +loglik = log(lik); + +engine.T = T; +engine.mu = mu; +engine.Sigma = Sigma; + +dnodes = bnet.dnodes; +dobs = myintersect(dnodes, onodes); +ens(dobs) = 1; +engine.joint_dmarginal = dpot(dnodes, ens(dnodes), myreshape(engine.T, ens(dnodes))); + +engine.onodes = onodes;