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1 function [engine, loglik] = enter_evidence(engine, evidence, varargin)
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2 % ENTER_EVIDENCE Add the specified evidence to the network (global_joint)
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3 % [engine, loglik] = enter_evidence(engine, evidence, ...)
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4 %
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5 % evidence{i} = [] if if X(i) is hidden, and otherwise contains its observed value.
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6 %
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7 % Warning: Computing the log likelihood requires marginalizing all the nodes and can be slow.
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8 %
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9 % The list below gives optional arguments [default value in brackets].
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10 %
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11 % exclude - list of nodes whose potential will not be included in the joint [ [] ]
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12 %
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13 % e.g., engine = enter_evidence(engine, ev, 'exclude', 3)
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14
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15 exclude = [];
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16 maximize = 0;
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17
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18 if nargin >= 3
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19 args = varargin;
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20 nargs = length(args);
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21 for i=1:2:nargs
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22 switch args{i},
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23 case 'exclude', exclude = args{i+1};
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24 case 'maximize', maximize = args{i+1};
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25 otherwise,
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26 error(['invalid argument name ' args{i}]);
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27 end
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28 end
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29 end
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30
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31 assert(~maximize)
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32 bnet = bnet_from_engine(engine);
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33 N = length(bnet.node_sizes);
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34 %[engine.jpot, loglik] = compute_joint_pot(bnet, mysetdiff(1:N, exclude), evidence, 1:N);
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35 [engine.jpot] = compute_joint_pot(bnet, mysetdiff(1:N, exclude), evidence, 1:N);
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36 % jpot should not be normalized, otherwise it gives wrong resutls for limids like asia_dt1
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37 if nargout == 2
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38 [m] = marginal_nodes(engine, []);
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39 [T, lik] = normalize(m.T);
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40 loglik = log(lik);
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41 end
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42 %[engine.jpot loglik] = normalize_pot(engine.jpot);
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