| #pragma once |
|
|
| #include <cassert> |
|
|
| #include <queue> |
| #include <vector> |
|
|
| #include <boost/unordered_map.hpp> |
| #include <boost/unordered_set.hpp> |
| #include <boost/weak_ptr.hpp> |
|
|
| #include "moses/ScoreComponentCollection.h" |
| #include "moses/FF/InternalTree.h" |
|
|
| #include "SHyperedge.h" |
| #include "SVertex.h" |
|
|
| namespace Moses |
| { |
| namespace Syntax |
| { |
|
|
| |
| |
| |
| |
| |
| |
| class KBestExtractor |
| { |
| public: |
| struct KVertex; |
|
|
| struct KHyperedge { |
| KHyperedge(const SHyperedge &e) : shyperedge(e) {} |
|
|
| const SHyperedge ­peredge; |
| boost::shared_ptr<KVertex> head; |
| std::vector<boost::shared_ptr<KVertex> > tail; |
| }; |
|
|
| struct Derivation { |
| Derivation(const boost::shared_ptr<KHyperedge> &); |
| Derivation(const Derivation &, std::size_t); |
|
|
| boost::shared_ptr<KHyperedge> edge; |
| std::vector<std::size_t> backPointers; |
| std::vector<boost::shared_ptr<Derivation> > subderivations; |
| ScoreComponentCollection scoreBreakdown; |
| float score; |
| }; |
|
|
| struct DerivationOrderer { |
| bool operator()(const boost::weak_ptr<Derivation> &d1, |
| const boost::weak_ptr<Derivation> &d2) const { |
| boost::shared_ptr<Derivation> s1(d1); |
| boost::shared_ptr<Derivation> s2(d2); |
| return s1->score < s2->score; |
| } |
| }; |
|
|
| struct KVertex { |
| typedef std::priority_queue<boost::weak_ptr<Derivation>, |
| std::vector<boost::weak_ptr<Derivation> >, |
| DerivationOrderer> DerivationQueue; |
|
|
| KVertex(const SVertex &v) : svertex(v), visited(false) {} |
|
|
| const SVertex &svertex; |
| std::vector<boost::weak_ptr<Derivation> > kBestList; |
| DerivationQueue candidates; |
| bool visited; |
| }; |
|
|
| typedef std::vector<boost::shared_ptr<Derivation> > KBestVec; |
|
|
| |
| |
| void Extract(const std::vector<boost::shared_ptr<SVertex> > &, std::size_t, |
| KBestVec &); |
|
|
| static Phrase GetOutputPhrase(const Derivation &); |
| static TreePointer GetOutputTree(const Derivation &); |
|
|
| private: |
| typedef boost::unordered_map<const SVertex *, |
| boost::shared_ptr<KVertex> > VertexMap; |
|
|
| struct DerivationHasher { |
| std::size_t operator()(const boost::shared_ptr<Derivation> &d) const { |
| std::size_t seed = 0; |
| boost::hash_combine(seed, &(d->edge->shyperedge)); |
| boost::hash_combine(seed, d->backPointers); |
| return seed; |
| } |
| }; |
|
|
| struct DerivationEqualityPred { |
| bool operator()(const boost::shared_ptr<Derivation> &d1, |
| const boost::shared_ptr<Derivation> &d2) const { |
| return &(d1->edge->shyperedge) == &(d2->edge->shyperedge) && |
| d1->backPointers == d2->backPointers; |
| } |
| }; |
|
|
| typedef boost::unordered_set<boost::shared_ptr<Derivation>, DerivationHasher, |
| DerivationEqualityPred> DerivationSet; |
|
|
| boost::shared_ptr<KVertex> FindOrCreateVertex(const SVertex &); |
| void GetCandidates(boost::shared_ptr<KVertex>, std::size_t); |
| void LazyKthBest(boost::shared_ptr<KVertex>, std::size_t, std::size_t); |
| void LazyNext(KVertex &, const Derivation &, std::size_t); |
|
|
| VertexMap m_vertexMap; |
| DerivationSet m_derivations; |
| }; |
|
|
| } |
| } |
|
|
