function [engine, loglik] = enter_evidence(engine, evidence, varargin)% ENTER_EVIDENCE Add the specified evidence to the network (jtree_dbn)% [engine, loglik] = enter_evidence(engine, evidence, ...)%% evidence{i,t} = [] if if X(i,t) is hidden, and otherwise contains its observed value (scalar or column vector)%% The following optional arguments can be specified in the form of name/value pairs:% [default value in brackets]%% maximize - if 1, does max-product instead of sum-product [engine.maximize]% softCPDpot{n,t} - use soft potential for node n instead of its CPD; set to [] to use CPD% soft_evidence_nodes(i,1:2) = [n t] means the i'th piece of soft evidence is on node n in slice t % soft_evidence{i} - prob distribution over values for soft_evidence_nodes(i,:)%% e.g., engine = enter_evidence(engine, ev, 'maximize', 1)% for add_ev in marginal_nodesT = size(evidence, 2);engine.evidence = evidence;bnet = bnet_from_engine(engine);ss = length(bnet.node_sizes_slice);ns = bnet.node_sizes_slice(:);engine.node_sizes = repmat(ns, [1 T]);softCPDpot = cell(ss,T);soft_evidence = {};soft_evidence_nodes = [];% parse optional paramsargs = varargin;nargs = length(args);if nargs > 0  for i=1:2:nargs    switch args{i},     case 'maximize', engine.maximize = args{i+1};      case 'softCPDpot', softCPDpot = args{i+1};     case 'soft_evidence', soft_evidence = args{i+1};     case 'soft_evidence_nodes', soft_evidence_nodes = args{i+1};     otherwise,        error(['invalid argument name ' args{i}]);           end  endendengine.jtree_engine = set_fields(engine.jtree_engine, 'maximize', engine.maximize);engine.jtree_engine1 = set_fields(engine.jtree_engine1, 'maximize', engine.maximize);[ss T] = size(evidence);engine.T = T;observed_bitv = ~isemptycell(evidence);onodes = find(observed_bitv);pot_type = determine_pot_type(bnet, onodes);CPDpot = convert_dbn_CPDs_to_pots(bnet, evidence, pot_type, softCPDpot);if ~isempty(soft_evidence_nodes)  nsoft = size(soft_evidence_nodes,1);  for i=1:nsoft    n = soft_evidence_nodes(i,1);    t = soft_evidence_nodes(i,2);    if t==1      dom = n;    else      dom = n+ss;    end    pot = dpot(dom, ns(n), soft_evidence{i});    CPDpot{n,t} = multiply_by_pot(CPDpot{n,t}, pot);  endend  [engine.clpot, loglik] = enter_soft_evidence(engine, CPDpot, observed_bitv, pot_type);