function logp = enumerate_HMM_loglik(prior, transmat, obsmat)% ENUMERATE_HMM_LOGLIK Compute the log likelihood of a sequence by exhaustive (O(Q^T)) enumeration.% logp = enumerate_HMM_loglik(prior, transmat, obsmat)%% Inputs:% prior(i) = Pr(Q(1) = i)% transmat(i,j) = Pr(Q(t+1)=j | Q(t)=i)% obsmat(i,t) = Pr(y(t) | Q(t)=i)Q = length(prior);T = size(obsmat, 2);sizes = repmat(Q, 1, T);psum = 0;for i=1:Q^T  qs = ind2subv(sizes, i); % make the state sequence   psum = psum + prob_path(prior, transmat, obsmat, qs);endlogp = log(psum)