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diff --git a/sourcecodes/bnt-master/BNT/CPDs/@discrete_CPD/log_prob_node.m b/sourcecodes/bnt-master/BNT/CPDs/@discrete_CPD/log_prob_node.m
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+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 p
+tiny = exp(-700);
+p = p + (p==0)*tiny; % replace 0s by tiny
+L = sum(log(p));