diff options
Diffstat (limited to 'sourcecodes/bnt-master/BNT/CPDs/@tabular_CPD/log_prior.m')
| -rw-r--r-- | sourcecodes/bnt-master/BNT/CPDs/@tabular_CPD/log_prior.m | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/sourcecodes/bnt-master/BNT/CPDs/@tabular_CPD/log_prior.m b/sourcecodes/bnt-master/BNT/CPDs/@tabular_CPD/log_prior.m new file mode 100644 index 00000000..1ac2dbd4 --- /dev/null +++ b/sourcecodes/bnt-master/BNT/CPDs/@tabular_CPD/log_prior.m @@ -0,0 +1,18 @@ +function L = log_prior(CPD) +% LOG_PRIOR Return log P(theta) for a tabular CPD +% L = log_prior(CPD) + +switch CPD.prior_type + case 'none', + L = 0; + case 'dirichlet', + D = CPD.dirichlet(:); + L = sum(log(D + (D==0))); + case 'entropic', + % log-prior = log exp(-H(theta)) = sum_i theta_i log (theta_i) + fam_sz = CPD.sizes; + psz = prod(fam_sz(1:end-1)); + ssz = fam_sz(end); + C = reshape(CPD.CPT, psz, ssz); + L = sum(sum(C .* log(C + (C==0)))); +end |