annotate toolboxes/FullBNT-1.0.7/bnt/CPDs/@discrete_CPD/log_prob_node.m @ 0:e9a9cd732c1e
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first hg version after svn
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wolffd |
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Tue, 10 Feb 2015 15:05:51 +0000 |
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1 function L = log_prob_node(CPD, self_ev, pev)
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2 % LOG_PROB_NODE Compute sum_m log P(x(i,m)| x(pi_i,m), theta_i) for node i (discrete)
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3 % L = log_prob_node(CPD, self_ev, pev)
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4 %
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5 % self_ev(m) is the evidence on this node in case m.
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6 % pev(i,m) is the evidence on the i'th parent in case m (if there are any parents).
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7 % (These may also be cell arrays.)
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8
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9 [P, p] = prob_node(CPD, self_ev, pev); % P may underflow, so we use p
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10 tiny = exp(-700);
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11 p = p + (p==0)*tiny; % replace 0s by tiny
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12 L = sum(log(p));
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