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#include "hg.h"
#include "lazy.h"
#include "fdict.h"
#include "tdict.h"
#include "lm/enumerate_vocab.hh"
#include "lm/model.hh"
#include "search/config.hh"
#include "search/context.hh"
#include "search/edge.hh"
#include "search/vertex.hh"
#include "search/vertex_generator.hh"
#include "util/exception.hh"
#include <boost/scoped_ptr.hpp>
#include <boost/scoped_array.hpp>
#include <iostream>
#include <vector>
namespace {
struct MapVocab : public lm::EnumerateVocab {
public:
MapVocab() {}
// Do not call after Lookup.
void Add(lm::WordIndex index, const StringPiece &str) {
const WordID cdec_id = TD::Convert(str.as_string());
if (cdec_id >= out_.size()) out_.resize(cdec_id + 1);
out_[cdec_id] = index;
}
// Assumes Add has been called and will never be called again.
lm::WordIndex FromCDec(WordID id) const {
return out_[out_.size() > id ? id : 0];
}
private:
std::vector<lm::WordIndex> out_;
};
class LazyBase {
public:
LazyBase(const std::vector<weight_t> &weights) :
cdec_weights_(weights),
config_(search::Weights(weights[FD::Convert("KLanguageModel")], weights[FD::Convert("KLanguageModel_OOV")], weights[FD::Convert("WordPenalty")]), 1000) {
std::cerr << "Weights KLanguageModel " << config_.GetWeights().LM() << " KLanguageModel_OOV " << config_.GetWeights().OOV() << " WordPenalty " << config_.GetWeights().WordPenalty() << std::endl;
}
virtual ~LazyBase() {}
virtual void Search(const Hypergraph &hg) const = 0;
static LazyBase *Load(const char *model_file, const std::vector<weight_t> &weights);
protected:
lm::ngram::Config GetConfig() {
lm::ngram::Config ret;
ret.enumerate_vocab = &vocab_;
return ret;
}
MapVocab vocab_;
const std::vector<weight_t> &cdec_weights_;
const search::Config config_;
};
template <class Model> class Lazy : public LazyBase {
public:
Lazy(const char *model_file, const std::vector<weight_t> &weights) : LazyBase(weights), m_(model_file, GetConfig()) {}
void Search(const Hypergraph &hg) const;
private:
void ConvertEdge(const search::Context<Model> &context, bool final, search::Vertex *vertices, const Hypergraph::Edge &in, search::Edge &out) const;
const Model m_;
};
LazyBase *LazyBase::Load(const char *model_file, const std::vector<weight_t> &weights) {
lm::ngram::ModelType model_type;
if (!lm::ngram::RecognizeBinary(model_file, model_type)) model_type = lm::ngram::PROBING;
switch (model_type) {
case lm::ngram::PROBING:
return new Lazy<lm::ngram::ProbingModel>(model_file, weights);
case lm::ngram::REST_PROBING:
return new Lazy<lm::ngram::RestProbingModel>(model_file, weights);
default:
UTIL_THROW(util::Exception, "Sorry this lm type isn't supported yet.");
}
}
void PrintFinal(const Hypergraph &hg, const search::Edge *edge_base, const search::Final &final) {
const std::vector<WordID> &words = hg.edges_[&final.From() - edge_base].rule_->e();
boost::array<const search::Final*, search::kMaxArity>::const_iterator child(final.Children().begin());
for (std::vector<WordID>::const_iterator i = words.begin(); i != words.end(); ++i) {
if (*i > 0) {
std::cout << TD::Convert(*i) << ' ';
} else {
PrintFinal(hg, edge_base, **child++);
}
}
}
template <class Model> void Lazy<Model>::Search(const Hypergraph &hg) const {
boost::scoped_array<search::Vertex> out_vertices(new search::Vertex[hg.nodes_.size()]);
boost::scoped_array<search::Edge> out_edges(new search::Edge[hg.edges_.size()]);
search::Context<Model> context(config_, m_);
for (unsigned int i = 0; i < hg.nodes_.size(); ++i) {
search::Vertex &out_vertex = out_vertices[i];
const Hypergraph::EdgesVector &down_edges = hg.nodes_[i].in_edges_;
for (unsigned int j = 0; j < down_edges.size(); ++j) {
unsigned int edge_index = down_edges[j];
ConvertEdge(context, i == hg.nodes_.size() - 1, out_vertices.get(), hg.edges_[edge_index], out_edges[edge_index]);
out_vertex.Add(out_edges[edge_index]);
}
out_vertex.FinishedAdding();
search::VertexGenerator(context, out_vertex);
}
search::PartialVertex top = out_vertices[hg.nodes_.size() - 1].RootPartial();
if (top.Empty()) {
std::cout << "NO PATH FOUND";
} else {
search::PartialVertex continuation;
while (!top.Complete()) {
top.Split(continuation);
top = continuation;
}
PrintFinal(hg, out_edges.get(), top.End());
std::cout << "||| " << top.End().Bound() << std::endl;
}
}
// TODO: get weights into here somehow.
template <class Model> void Lazy<Model>::ConvertEdge(const search::Context<Model> &context, bool final, search::Vertex *vertices, const Hypergraph::Edge &in, search::Edge &out) const {
const std::vector<WordID> &e = in.rule_->e();
std::vector<lm::WordIndex> words;
unsigned int terminals = 0;
for (std::vector<WordID>::const_iterator word = e.begin(); word != e.end(); ++word) {
if (*word <= 0) {
out.Add(vertices[in.tail_nodes_[-*word]]);
words.push_back(lm::kMaxWordIndex);
} else {
++terminals;
words.push_back(vocab_.FromCDec(*word));
}
}
if (final) {
words.push_back(m_.GetVocabulary().EndSentence());
}
float additive = in.rule_->GetFeatureValues().dot(cdec_weights_);
UTIL_THROW_IF(isnan(additive), util::Exception, "Bad dot product");
additive -= static_cast<float>(terminals) * context.GetWeights().WordPenalty() / M_LN10;
out.InitRule().Init(context, additive, words, final);
}
boost::scoped_ptr<LazyBase> AwfulGlobalLazy;
} // namespace
void PassToLazy(const char *model_file, const std::vector<weight_t> &weights, const Hypergraph &hg) {
if (!AwfulGlobalLazy.get()) {
AwfulGlobalLazy.reset(LazyBase::Load(model_file, weights));
}
AwfulGlobalLazy->Search(hg);
}
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