wolffd@0: function CPD = update_ess(CPD, fmarginal, evidence, ns, cnodes, hidden_bitv)
wolffd@0: % UPDATE_ESS Update the Expected Sufficient Statistics of a hhmm Q node.
wolffd@0: % function CPD = update_ess(CPD, fmarginal, evidence, ns, cnodes, idden_bitv)
wolffd@0: %
wolffd@0: % we assume if one of the Qps is observed, all of them are 
wolffd@0: % We assume the F nodes are already hidden 
wolffd@0: 
wolffd@0: % Figure out the node numbers associated with each parent
wolffd@0: dom = fmarginal.domain;
wolffd@0: self = dom(CPD.self_ndx);
wolffd@0: old_self = dom(CPD.old_self_ndx);
wolffd@0: %Fself = dom(CPD.Fself_ndx);
wolffd@0: %Fbelow = dom(CPD.Fbelow_ndx);
wolffd@0: Qps = dom(CPD.Qps_ndx);
wolffd@0: 
wolffd@0: Qsz = CPD.Qsz;
wolffd@0: Qpsz = CPD.Qpsz;
wolffd@0: 
wolffd@0: 
wolffd@0: % hor_counts(old_self, Qps, self),
wolffd@0: % fmarginal(old_self, Fbelow, Fself, Qps, self)
wolffd@0: % hor_counts(i,k,j) = fmarginal(i,2,1,k,j) % below has finished, self has not
wolffd@0: % ver_counts(i,k,j) = fmarginal(i,2,2,k,j) % below has finished, and so has self (reset)
wolffd@0: % Since any of i,j,k may be observed, we write
wolffd@0: % hor_counts(ndx{:}) = fmarginal(...)
wolffd@0: % where e.g., ndx = {1, ':', 2} if Qps is hidden but we observe old_self=1, self=2.
wolffd@0: 
wolffd@0: % ndx{i,k,j}
wolffd@0: if hidden_bitv(old_self)
wolffd@0:   ndx{1} = ':';
wolffd@0: else
wolffd@0:   ndx{1} = evidence{old_self};
wolffd@0: end
wolffd@0: if hidden_bitv(Qps)
wolffd@0:   ndx{2} = ':';
wolffd@0: else
wolffd@0:   ndx{2} = subv2ind(Qpsz, cat(1, evidence{Qps}));
wolffd@0: end
wolffd@0: if hidden_bitv(self)
wolffd@0:   ndx{3} = ':';
wolffd@0: else
wolffd@0:   ndx{3} = evidence{self};
wolffd@0: end
wolffd@0: 
wolffd@0: fmarg = add_ev_to_dmarginal(fmarginal, evidence, ns);
wolffd@0: % marg(Qold(t-1), Fbelow(t-1), Fself(t-1), Qps(t), Qself(t))                            
wolffd@0: hor_counts = zeros(Qsz, Qpsz, Qsz);
wolffd@0: ver_counts = zeros(Qpsz, Qsz);
wolffd@0:     
wolffd@0: if ~isempty(CPD.Fbelow_ndx)
wolffd@0:   if ~isempty(CPD.Fself_ndx) % general case
wolffd@0:     fmarg.T = myreshape(fmarg.T, [Qsz 2 2 Qpsz Qsz]);
wolffd@0:     marg_ndx = {ndx{1}, 2, 1, ndx{2}, ndx{3}};
wolffd@0:     hor_counts(ndx{:}) = fmarg.T(marg_ndx{:});
wolffd@0:     ver_counts(ndx{2:3}) = ... % sum over Fbelow and Qold=i
wolffd@0: 	sum(fmarg.T({ndx{1}, 1, 2, ndx{2}, ndx{3}}),1) + ..
wolffd@0: 	sum(fmarg.T({ndx{1}, 2, 2, ndx{2}, ndx{3}}),1);
wolffd@0:   else % no F from self, hence no startprob
wolffd@0:     fmarg.T = myreshape(fmarg.T, [Qsz 2 Qpsz Qsz]);
wolffd@0:     hor_counts(ndx{:}) = fmarg.T({ndx{1}, 2, ndx{2}, ndx{3}});
wolffd@0:   end
wolffd@0: else % no F signal from below
wolffd@0:   if ~isempty(CPD.Fself_ndx) % self F
wolffd@0:     fmarg.T = myreshape(fmarg.T, [Qsz 2 Qpsz Qsz]);
wolffd@0:     hor_counts(ndx{:}) = fmarg.T({ndx{1}, 1, ndx{2}, ndx{3}});
wolffd@0:     ver_counts(ndx{2:3}) = ... % sum over Qold=i
wolffd@0: 	sum(fmarg.T({ndx{1}, 2, ndx{2}, ndx{3}}),1);
wolffd@0:   else % no F from self
wolffd@0:     error('An hhmmQ node without any F parents is just a tabular_CPD')
wolffd@0:   end
wolffd@0: end
wolffd@0: 
wolffd@0: 
wolffd@0: CPD.sub_CPD_trans = update_ess_simple(CPD.sub_CPD_trans, hor_counts);
wolffd@0: 
wolffd@0: if ~isempty(CPD.sub_CPD_start)
wolffd@0:   CPD.sub_CPD_start = update_ess_simple(CPD.sub_CPD_start, ver_counts);
wolffd@0: end
wolffd@0: 
wolffd@0: