annotate toolboxes/FullBNT-1.0.7/bnt/inference/dynamic/@ff_inf_engine/enter_evidence.m @ 0:cc4b1211e677 tip

initial commit to HG from Changeset: 646 (e263d8a21543) added further path and more save "camirversion.m"
author Daniel Wolff
date Fri, 19 Aug 2016 13:07:06 +0200
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Daniel@0 1 function [engine, loglik] = enter_evidence(engine, evidence, varargin)
Daniel@0 2 % ENTER_EVIDENCE Add the specified evidence to the network (ff)
Daniel@0 3 % [engine, loglik] = enter_evidence(engine, evidence, ...)
Daniel@0 4 %
Daniel@0 5 % evidence{i,t} = [] if if X(i,t) is hidden, and otherwise contains its observed value (scalar or
Daniel@0 6 % column vector)
Daniel@0 7 %
Daniel@0 8 % The following optional arguments can be specified in the form of name/value pairs:
Daniel@0 9 % [default value in brackets]
Daniel@0 10 %
Daniel@0 11 % maximize - if 1, does max-product (not yet supported), else sum-product [0]
Daniel@0 12 % filter - if 1, do filtering, else smoothing [0]
Daniel@0 13 %
Daniel@0 14 % e.g., engine = enter_evidence(engine, ev, 'maximize', 1)
Daniel@0 15
Daniel@0 16 maximize = 0;
Daniel@0 17 filter = 0;
Daniel@0 18
Daniel@0 19 % parse optional params
Daniel@0 20 args = varargin;
Daniel@0 21 nargs = length(args);
Daniel@0 22 if nargs > 0
Daniel@0 23 for i=1:2:nargs
Daniel@0 24 switch args{i},
Daniel@0 25 case 'maximize', maximize = args{i+1};
Daniel@0 26 case 'filter', filter = args{i+1};
Daniel@0 27 otherwise,
Daniel@0 28 error(['invalid argument name ' args{i}]);
Daniel@0 29 end
Daniel@0 30 end
Daniel@0 31 end
Daniel@0 32
Daniel@0 33 assert(~maximize);
Daniel@0 34
Daniel@0 35
Daniel@0 36 [ss T] = size(evidence);
Daniel@0 37 observed = ~isemptycell(evidence);
Daniel@0 38 bnet = bnet_from_engine(engine);
Daniel@0 39 %pot_type = determine_pot_type(find(observed(:,1)), bnet.cnodes_slice, bnet.intra);
Daniel@0 40 pot_type = determine_pot_type(bnet, observed);
Daniel@0 41 % we assume we can use the same pot_type in all slices
Daniel@0 42
Daniel@0 43 CPDpot = convert_dbn_CPDs_to_pots(bnet, evidence, pot_type);
Daniel@0 44
Daniel@0 45 % Now convert CPDs on observed nodes to be potentials just on their parents
Daniel@0 46 assert(pot_type == 'd');
Daniel@0 47 onodes = bnet.observed(:);
Daniel@0 48 ns = bnet.node_sizes_slice;
Daniel@0 49 ns(onodes) = 1;
Daniel@0 50 for t=1:T
Daniel@0 51 for i=onodes
Daniel@0 52 p = parents(bnet.dag, i);
Daniel@0 53 %CPDpot{i,t} = set_domain_pot(CPDpot{i,t}, p); % leaves size too long
Daniel@0 54 temp = pot_to_marginal(CPDpot{i,t});
Daniel@0 55 CPDpot{i,t} = dpot(p, ns(p), temp.T); % assumes pot_type = d
Daniel@0 56 end
Daniel@0 57 end
Daniel@0 58
Daniel@0 59 [engine.marginals, engine.fwd, engine.back, loglik] = enter_soft_evidence(engine, CPDpot, observed, pot_type, filter);
Daniel@0 60
Daniel@0 61 engine.CPDpot = CPDpot;
Daniel@0 62 engine.filter = filter;