mosesdecoder/moses/ChartHypothesisCollection.h
2012-11-12 19:56:18 +00:00

126 lines
3.8 KiB
C++

// $Id$
// vim:tabstop=2
/***********************************************************************
Moses - factored phrase-based language decoder
Copyright (C) 2010 Hieu Hoang
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
***********************************************************************/
#pragma once
#include <set>
#include "ChartHypothesis.h"
#include "RuleCube.h"
namespace Moses
{
//! functor to compare (chart) hypotheses by (descending) score
class ChartHypothesisScoreOrderer
{
public:
bool operator()(const ChartHypothesis* hypoA, const ChartHypothesis* hypoB) const {
return hypoA->GetTotalScore() > hypoB->GetTotalScore();
}
};
/** functor to compare (chart) hypotheses by feature function states.
* If 2 hypos are equal, according to this functor, then they can be recombined.
*/
class ChartHypothesisRecombinationOrderer
{
public:
bool operator()(const ChartHypothesis* hypoA, const ChartHypothesis* hypoB) const {
// assert in same cell
const WordsRange &rangeA = hypoA->GetCurrSourceRange()
, &rangeB = hypoB->GetCurrSourceRange();
CHECK(rangeA == rangeB);
// shouldn't be mixing hypos with different lhs
CHECK(hypoA->GetTargetLHS() == hypoB->GetTargetLHS());
int ret = hypoA->RecombineCompare(*hypoB);
if (ret != 0)
return (ret < 0);
return false;
}
};
/** Contains a set of unique hypos that have the same HS non-term.
* ie. 1 of these for each target LHS in each cell
*/
class ChartHypothesisCollection
{
friend std::ostream& operator<<(std::ostream&, const ChartHypothesisCollection&);
protected:
typedef std::set<ChartHypothesis*, ChartHypothesisRecombinationOrderer> HCType;
HCType m_hypos;
HypoList m_hyposOrdered;
float m_bestScore; /**< score of the best hypothesis in collection */
float m_beamWidth; /**< minimum score due to threashold pruning */
size_t m_maxHypoStackSize; /**< maximum number of hypothesis allowed in this stack */
bool m_nBestIsEnabled; /**< flag to determine whether to keep track of old arcs */
std::pair<HCType::iterator, bool> Add(ChartHypothesis *hypo, ChartManager &manager);
public:
typedef HCType::iterator iterator;
typedef HCType::const_iterator const_iterator;
//! iterators
const_iterator begin() const {
return m_hypos.begin();
}
const_iterator end() const {
return m_hypos.end();
}
ChartHypothesisCollection();
~ChartHypothesisCollection();
bool AddHypothesis(ChartHypothesis *hypo, ChartManager &manager);
void Detach(const HCType::iterator &iter);
void Remove(const HCType::iterator &iter);
void PruneToSize(ChartManager &manager);
size_t GetSize() const {
return m_hypos.size();
}
size_t GetHypo() const {
return m_hypos.size();
}
void SortHypotheses();
void CleanupArcList();
//! return vector of hypothesis that has been sorted by score
const HypoList &GetSortedHypotheses() const {
return m_hyposOrdered;
}
//! return the best total score of all hypos in this collection
float GetBestScore() const { return m_bestScore; }
void GetSearchGraph(long translationId, std::ostream &outputSearchGraphStream, const std::map<unsigned,bool> &reachable) const;
};
} // namespace