diff options
author | Chris Dyer <cdyer@cs.cmu.edu> | 2011-03-22 14:44:46 -0400 |
---|---|---|
committer | Chris Dyer <cdyer@cs.cmu.edu> | 2011-03-22 14:44:46 -0400 |
commit | c0ae6f362b245ccf2ab3b8d6dc7e367cbcc64c1c (patch) | |
tree | 1f24d437285147f08d8dd868dc1cb217e208c931 | |
parent | 4bc9ea17ba9f85c899e35a9d657ee3f174ff2863 (diff) |
fix local normalizer code for summary features
-rw-r--r-- | decoder/decoder.cc | 16 | ||||
-rw-r--r-- | decoder/hg.cc | 5 | ||||
-rw-r--r-- | decoder/hg.h | 2 |
3 files changed, 15 insertions, 8 deletions
diff --git a/decoder/decoder.cc b/decoder/decoder.cc index a16a9b5a..89425198 100644 --- a/decoder/decoder.cc +++ b/decoder/decoder.cc @@ -806,15 +806,21 @@ bool DecoderImpl::Decode(const string& input, DecoderObserver* o) { } if (rp.fid_summary) { - Hypergraph::EdgeProbs posteriors; - const prob_t z = forest.ComputeEdgePosteriors(1.0, &posteriors); + const prob_t z = forest.PushWeightsToGoal(1.0); if (!SILENT) { cerr << " " << passtr << " adding summary feature " << FD::Convert(rp.fid_summary) << " log(Z)=" << log(z) << endl; } - assert(forest.edges_.size() == posteriors.size()); if (!isfinite(log(z)) || isnan(log(z))) { cerr << " " << passtr << " !!! Invalid partition detected, abandoning.\n"; } else { - for (int i = 0; i < posteriors.size(); ++i) - forest.edges_[i].feature_values_.set_value(rp.fid_summary, log(posteriors[i] / z)); + for (int i = 0; i < forest.edges_.size(); ++i) { + const double log_prob_transition = log(forest.edges_[i].edge_prob_); // locally normalized by the edge + // head node by forest.PushWeightsToGoal + if (!isfinite(log_prob_transition) || isnan(log_prob_transition)) { + cerr << "Edge: i=" << i << " got bad inside prob: " << *forest.edges_[i].rule_ << endl; + abort(); + } + + forest.edges_[i].feature_values_.set_value(rp.fid_summary, log_prob_transition); + } } } diff --git a/decoder/hg.cc b/decoder/hg.cc index 39ac5132..a4028b0e 100644 --- a/decoder/hg.cc +++ b/decoder/hg.cc @@ -226,9 +226,9 @@ prob_t Hypergraph::PushViterbiWeightsToGoal(int fid) { } -void Hypergraph::PushWeightsToGoal(double scale) { +prob_t Hypergraph::PushWeightsToGoal(double scale) { vector<prob_t> posts; - ComputeEdgePosteriors(scale, &posts); + const prob_t inside_z = ComputeEdgePosteriors(scale, &posts); for (int i = 0; i < nodes_.size(); ++i) { const Hypergraph::Node& node = nodes_[i]; prob_t z = prob_t::Zero(); @@ -238,6 +238,7 @@ void Hypergraph::PushWeightsToGoal(double scale) { edges_[node.in_edges_[j]].edge_prob_ = posts[node.in_edges_[j]] / z; } } + return inside_z; } struct EdgeExistsWeightFunction { diff --git a/decoder/hg.h b/decoder/hg.h index aa1202b1..e5ef05f8 100644 --- a/decoder/hg.h +++ b/decoder/hg.h @@ -449,7 +449,7 @@ public: void PushWeightsToSource(double scale = 1.0); // same, except weights are pushed to the goal, works for HGs, // not just lattices - void PushWeightsToGoal(double scale = 1.0); + prob_t PushWeightsToGoal(double scale = 1.0); // contrary to PushWeightsToGoal, use viterbi semiring; store log(p) to fid. note that p_viterbi becomes 1; k*p_viterbi becomes k. also modifies edge_prob_ (note that the fid stored log(p) will stick around even if you reweight) // afterwards, product of edge_prob_ for a derivation will equal 1 for the viterbi (p_v before, 1 after), and in general (k*p_v before, k after). returns inside(goal) |