function L = log_prob_node(CPD, self_ev, pev)% LOG_PROB_NODE Compute sum_m log P(x(i,m)| x(pi_i,m), theta_i) for node i (discrete)% L = log_prob_node(CPD, self_ev, pev)%% self_ev(m) is the evidence on this node in case m.% pev(i,m) is the evidence on the i'th parent in case m (if there are any parents).% (These may also be cell arrays.)[P, p] = prob_node(CPD, self_ev, pev); % P may underflow, so we use ptiny = exp(-700);p = p + (p==0)*tiny; % replace 0s by tinyL = sum(log(p));