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1 function CPD = maximize_params(CPD, temp)
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2 % MAXIMIZE_PARAMS Set the params of a hhmmQ node to their ML/MAP values.
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3 % CPD = maximize_params(CPD, temperature)
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4
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5 Qsz = CPD.Qsizes(CPD.d);
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6 Qpsz = prod(CPD.Qsizes(CPD.Qps));
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7
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8 if ~isempty(CPD.sub_CPD_start)
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9 CPD.sub_CPD_start = maximize_params(CPD.sub_CPD_start, temp);
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10 S = struct(CPD.sub_CPD_start);
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11 CPD.startprob = myreshape(S.CPT, [Qpsz Qsz]);
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12 %CPD.startprob = S.CPT;
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13 end
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14
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15 if 1
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16 % If we are in a state that can only go the end state,
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17 % we will never see a transition to another (non-end) state,
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18 % so counts(i,k,j)=0 (and termprob(k,i)=1).
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19 % We set counts(i,k,i)=1 in this case.
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20 % This will cause remove_hhmm_end_state to return a
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21 % stochastic matrix, but otherwise has no effect on EM.
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22 counts = get_field(CPD.sub_CPD_trans, 'counts');
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23 counts = reshape(counts, [Qsz Qpsz Qsz]);
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24 for k=1:Qpsz
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25 for i=1:Qsz
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26 if sum(counts(i,k,:))==0 % never witnessed a transition out of i
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27 counts(i,k,i)=1; % add self loop
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28 %fprintf('CPDQ d=%d i=%d k=%d\n', CPD.d, i, k);
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29 end
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30 end
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31 end
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32 CPD.sub_CPD_trans = set_fields(CPD.sub_CPD_trans, 'counts', counts(:));
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33 end
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34
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35 CPD.sub_CPD_trans = maximize_params(CPD.sub_CPD_trans, temp);
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36 S = struct(CPD.sub_CPD_trans);
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37 %CPD.transprob = S.CPT;
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38 CPD.transprob = myreshape(S.CPT, [Qsz Qpsz Qsz]);
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39
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40 CPD = update_CPT(CPD);
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