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1 function CPD = update_ess(CPD, fmarginal, evidence, ns, cnodes, hidden_bitv)
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2 % UPDATE_ESS Update the Expected Sufficient Statistics of a hhmm Q node.
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3 % function CPD = update_ess(CPD, fmarginal, evidence, ns, cnodes, idden_bitv)
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4 %
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5 % we assume if one of the Qps is observed, all of them are
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6 % We assume the F nodes are already hidden
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7
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8 % Figure out the node numbers associated with each parent
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9 dom = fmarginal.domain;
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10 self = dom(end);
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11 old_self = dom(CPD.old_self_ndx);
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12 %Fself = dom(CPD.Fself_ndx);
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13 %Fbelow = dom(CPD.Fbelow_ndx);
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14 Qps = dom(CPD.Qps_ndx);
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15
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16 Qsz = CPD.Qsz;
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17 Qpsz = CPD.Qpsz;
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18
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19
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20 % hor_counts(old_self, Qps, self),
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21 % fmarginal(old_self, Fbelow, Fself, Qps, self)
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22 % hor_counts(i,k,j) = fmarginal(i,2,1,k,j) % below has finished, self has not
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23 % ver_counts(i,k,j) = fmarginal(i,2,2,k,j) % below has finished, and so has self (reset)
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24 % Since any of i,j,k may be observed, we write
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25 % hor_counts(i_counts_ndx, kndx, jndx) = fmarginal(i_fmarg_ndx...)
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26 % where i_fmarg_ndx = 1 and i_counts_ndx = i if old_self is observed to have value i,
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27 % i_fmarg_ndx = 1:Qsz and i_counts_ndx = 1:Qsz if old_self is hidden, etc.
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28
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29
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30 if hidden_bitv(old_self)
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31 i_counts_ndx = 1:Qsz;
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32 eff_oldQsz = Qsz;
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33 else
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34 i_counts_ndx = evidence{old_self};
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35 eff_oldQsz = 1;
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36 end
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37
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38 if all(hidden_bitv(Qps)) % we assume all are hidden or all are observed
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39 k_counts_ndx = 1:Qpsz;
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40 eff_Qpsz = Qpsz;
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41 else
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42 k_counts_ndx = subv2ind(Qpsz, cat(1, evidence{Qps}));
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43 eff_Qpsz = 1;
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44 end
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45
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46 if hidden_bitv(self)
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47 j_counts_ndx = 1:Qsz;
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48 eff_Qsz = Qsz;
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49 else
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50 j_counts_ndx = evidence{self};
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51 eff_Qsz = 1;
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52 end
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53
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54 hor_counts = zeros(Qsz, Qpsz, Qsz);
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55 ver_counts = zeros(Qpsz, Qsz);
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56
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57 if ~isempty(CPD.Fbelow_ndx)
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58 if ~isempty(CPD.Fself_ndx) % general case
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59 fmarg = myreshape(fmarginal.T, [eff_oldQsz 2 2 eff_Qpsz eff_Qsz]);
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60 hor_counts(i_counts_ndx, k_counts_ndx, j_counts_ndx) = fmarg(:, 2, 1, :, :);
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61 ver_counts(k_counts_ndx, j_counts_ndx) = ... % sum over Fbelow and Qold
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62 sumv(fmarg(:, :, 2, :, :), [1 2]); % require Fself=2
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63 else % no F from self, hence no startprob
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64 fmarg = myreshape(fmarginal.T, [eff_oldQsz 2 eff_Qpsz eff_Qsz]);
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65 hor_counts(i_counts_ndx, k_counts_ndx, j_counts_ndx) = ...
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66 fmarg(:, 2, :, :); % require Fbelow = 2
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67 end
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68 else % no F signal from below
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69 if ~isempty(CPD.Fself_ndx) % self F
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70 fmarg = myreshape(fmarginal.T, [eff_oldQsz 2 eff_Qpsz eff_Qsz]);
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71 hor_counts(i_counts_ndx, k_counts_ndx, j_counts_ndx) = fmarg(:, 1, :, :);
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72 ver_counts(k_counts_ndx, j_counts_ndx) = ... % sum over Qold
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73 squeeze(sum(fmarg(:, 2, :, :), 1)); % Fself=2
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74 else % no F from self
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75 error('An hhmmQ node without any F parents is just a tabular_CPD')
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76 end
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77 end
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78
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79
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80 CPD.sub_CPD_trans = update_ess_simple(CPD.sub_CPD_trans, hor_counts);
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81
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82 if ~isempty(CPD.sub_CPD_start)
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83 CPD.sub_CPD_start = update_ess_simple(CPD.sub_CPD_start, ver_counts);
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84 end
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85
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86
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