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mosesdecoder/moses/TranslationOptionCollection.cpp

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// $Id$
// vim:tabstop=2
/***********************************************************************
Moses - factored phrase-based language decoder
Copyright (C) 2006 University of Edinburgh
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
***********************************************************************/
#include <algorithm>
#include "TranslationOptionCollection.h"
#include "Sentence.h"
#include "DecodeStep.h"
#include "LM/Base.h"
#include "moses/TranslationModel/PhraseDictionaryMemory.h"
#include "FactorCollection.h"
#include "InputType.h"
#include "LexicalReordering.h"
#include "Util.h"
#include "StaticData.h"
#include "DecodeStepTranslation.h"
#include "DecodeGraph.h"
using namespace std;
namespace Moses
{
/** helper for pruning */
bool CompareTranslationOption(const TranslationOption *a, const TranslationOption *b)
{
return a->GetFutureScore() > b->GetFutureScore();
}
/** constructor; since translation options are indexed by coverage span, the corresponding data structure is initialized here
* This fn should be called by inherited classes
*/
TranslationOptionCollection::TranslationOptionCollection(const TranslationSystem* system,
InputType const& src, size_t maxNoTransOptPerCoverage, float translationOptionThreshold)
: m_system(system),
m_source(src)
,m_futureScore(src.GetSize())
,m_maxNoTransOptPerCoverage(maxNoTransOptPerCoverage)
,m_translationOptionThreshold(translationOptionThreshold)
{
// create 2-d vector
size_t size = src.GetSize();
for (size_t startPos = 0 ; startPos < size ; ++startPos) {
m_collection.push_back( vector< TranslationOptionList >() );
size_t maxSize = size - startPos;
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
for (size_t endPos = 0 ; endPos < maxSize ; ++endPos) {
m_collection[startPos].push_back( TranslationOptionList() );
}
}
}
/** destructor, clears out data structures */
TranslationOptionCollection::~TranslationOptionCollection()
{
RemoveAllInColl(m_unksrcs);
}
void TranslationOptionCollection::Prune()
{
// quit, if max size, threshold
if (m_maxNoTransOptPerCoverage == 0 && m_translationOptionThreshold == -std::numeric_limits<float>::infinity())
return;
// bookkeeping for how many options used, pruned
size_t total = 0;
size_t totalPruned = 0;
// loop through all spans
size_t size = m_source.GetSize();
for (size_t startPos = 0 ; startPos < size; ++startPos) {
size_t maxSize = size - startPos;
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
for (size_t endPos = startPos ; endPos < startPos + maxSize ; ++endPos) {
// consider list for a span
TranslationOptionList &fullList = GetTranslationOptionList(startPos, endPos);
total += fullList.size();
// size pruning
if (m_maxNoTransOptPerCoverage > 0 &&
fullList.size() > m_maxNoTransOptPerCoverage) {
// sort in vector
nth_element(fullList.begin(), fullList.begin() + m_maxNoTransOptPerCoverage, fullList.end(), CompareTranslationOption);
totalPruned += fullList.size() - m_maxNoTransOptPerCoverage;
// delete the rest
for (size_t i = m_maxNoTransOptPerCoverage ; i < fullList.size() ; ++i) {
delete fullList.Get(i);
}
fullList.resize(m_maxNoTransOptPerCoverage);
}
// threshold pruning
if (fullList.size() > 1 && m_translationOptionThreshold != -std::numeric_limits<float>::infinity()) {
// first, find the best score
float bestScore = -std::numeric_limits<float>::infinity();
for (size_t i=0; i < fullList.size() ; ++i) {
if (fullList.Get(i)->GetFutureScore() > bestScore)
bestScore = fullList.Get(i)->GetFutureScore();
}
//std::cerr << "best score for span " << startPos << "-" << endPos << " is " << bestScore << "\n";
// then, remove items that are worse than best score + threshold
for (size_t i=0; i < fullList.size() ; ++i) {
if (fullList.Get(i)->GetFutureScore() < bestScore + m_translationOptionThreshold) {
//std::cerr << "\tremoving item " << i << ", score " << fullList.Get(i)->GetFutureScore() << ": " << fullList.Get(i)->GetTargetPhrase() << "\n";
delete fullList.Get(i);
fullList.Remove(i);
total--;
totalPruned++;
i--;
}
//else
//{
// std::cerr << "\tkeeping item " << i << ", score " << fullList.Get(i)->GetFutureScore() << ": " << fullList.Get(i)->GetTargetPhrase() << "\n";
//}
}
} // end of threshold pruning
}
} // end of loop through all spans
VERBOSE(2," Total translation options: " << total << std::endl
<< "Total translation options pruned: " << totalPruned << std::endl);
}
/** Force a creation of a translation option where there are none for a particular source position.
* ie. where a source word has not been translated, create a translation option by
* 1. not observing the table limits on phrase/generation tables
* 2. using the handler ProcessUnknownWord()
* Call this function once translation option collection has been filled with translation options
*
* This function calls for unknown words is complicated by the fact it must handle different input types.
* The call stack is
* Base::ProcessUnknownWord()
* Inherited::ProcessUnknownWord(position)
* Base::ProcessOneUnknownWord()
*
* \param decodeStepList list of decoding steps
* \param factorCollection input sentence with all factors
*/
void TranslationOptionCollection::ProcessUnknownWord()
{
const vector<DecodeGraph*>& decodeGraphList = m_system->GetDecodeGraphs();
size_t size = m_source.GetSize();
// try to translation for coverage with no trans by expanding table limit
for (size_t graphInd = 0 ; graphInd < decodeGraphList.size() ; graphInd++) {
const DecodeGraph &decodeGraph = *decodeGraphList[graphInd];
for (size_t pos = 0 ; pos < size ; ++pos) {
TranslationOptionList &fullList = GetTranslationOptionList(pos, pos);
size_t numTransOpt = fullList.size();
if (numTransOpt == 0) {
CreateTranslationOptionsForRange(decodeGraph, pos, pos, false, graphInd);
}
}
}
bool alwaysCreateDirectTranslationOption = StaticData::Instance().IsAlwaysCreateDirectTranslationOption();
// create unknown words for 1 word coverage where we don't have any trans options
for (size_t pos = 0 ; pos < size ; ++pos) {
TranslationOptionList &fullList = GetTranslationOptionList(pos, pos);
if (fullList.size() == 0 || alwaysCreateDirectTranslationOption)
ProcessUnknownWord(pos);
}
}
/** special handling of ONE unknown words. Either add temporarily add word to translation table,
* or drop the translation.
* This function should be called by the ProcessOneUnknownWord() in the inherited class
* At the moment, this unknown word handler is a bit of a hack, if copies over each factor from source
* to target word, or uses the 'UNK' factor.
* Ideally, this function should be in a class which can be expanded upon, for example,
* to create a morphologically aware handler.
*
* \param sourceWord the unknown word
* \param sourcePos
* \param length length covered by this word (may be > 1 for lattice input)
* \param inputScores a set of scores associated with unknown word (input scores from latties/CNs)
*/
void TranslationOptionCollection::ProcessOneUnknownWord(const Word &sourceWord,size_t sourcePos, size_t length, const Scores *inputScores)
{
// unknown word, add as trans opt
FactorCollection &factorCollection = FactorCollection::Instance();
size_t isDigit = 0;
const Factor *f = sourceWord[0]; // TODO hack. shouldn't know which factor is surface
const string &s = f->GetString();
bool isEpsilon = (s=="" || s==EPSILON);
if (StaticData::Instance().GetDropUnknown())
{
isDigit = s.find_first_of("0123456789");
if (isDigit == 1)
isDigit = 1;
else
isDigit = 0;
// modify the starting bitmap
}
Phrase* m_unksrc = new Phrase(1);
m_unksrc->AddWord() = sourceWord;
m_unksrcs.push_back(m_unksrc);
TranslationOption *transOpt;
TargetPhrase targetPhrase;
targetPhrase.SetSourcePhrase(*m_unksrc);
if (inputScores != NULL) {
targetPhrase.SetScore(m_system,*inputScores);
} else {
targetPhrase.SetScore(m_system);
}
if (!(StaticData::Instance().GetDropUnknown() || isEpsilon) || isDigit)
{
// add to dictionary
Word &targetWord = targetPhrase.AddWord();
for (unsigned int currFactor = 0 ; currFactor < MAX_NUM_FACTORS ; currFactor++)
{
FactorType factorType = static_cast<FactorType>(currFactor);
const Factor *sourceFactor = sourceWord[currFactor];
if (sourceFactor == NULL)
targetWord[factorType] = factorCollection.AddFactor(UNKNOWN_FACTOR);
else
targetWord[factorType] = factorCollection.AddFactor(sourceFactor->GetString());
}
//create a one-to-one alignment between UNKNOWN_FACTOR and its verbatim translation
targetPhrase.SetAlignmentInfo("0-0");
}
else
{
// drop source word. create blank trans opt
//targetPhrase.SetAlignment();
}
transOpt = new TranslationOption(WordsRange(sourcePos, sourcePos + length - 1), targetPhrase, m_source
, m_system->GetUnknownWordPenaltyProducer());
transOpt->CalcScore(m_system);
Add(transOpt);
}
/** compute future score matrix in a dynamic programming fashion.
* This matrix used in search.
* Call this function once translation option collection has been filled with translation options
*/
void TranslationOptionCollection::CalcFutureScore()
{
// setup the matrix (ignore lower triangle, set upper triangle to -inf
size_t size = m_source.GetSize(); // the width of the matrix
for(size_t row=0; row<size; row++) {
for(size_t col=row; col<size; col++) {
m_futureScore.SetScore(row, col, -numeric_limits<float>::infinity());
}
}
// walk all the translation options and record the cheapest option for each span
for (size_t startPos = 0 ; startPos < size ; ++startPos) {
size_t maxSize = m_source.GetSize() - startPos;
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
for (size_t endPos = startPos ; endPos < startPos + maxSize ; ++endPos) {
TranslationOptionList &transOptList = GetTranslationOptionList(startPos, endPos);
TranslationOptionList::const_iterator iterTransOpt;
for(iterTransOpt = transOptList.begin() ; iterTransOpt != transOptList.end() ; ++iterTransOpt) {
const TranslationOption &transOpt = **iterTransOpt;
float score = transOpt.GetFutureScore();
if (score > m_futureScore.GetScore(startPos, endPos))
m_futureScore.SetScore(startPos, endPos, score);
}
}
}
// now fill all the cells in the strictly upper triangle
// there is no way to modify the diagonal now, in the case
// where no translation option covers a single-word span,
// we leave the +inf in the matrix
// like in chart parsing we want each cell to contain the highest score
// of the full-span trOpt or the sum of scores of joining two smaller spans
for(size_t colstart = 1; colstart < size ; colstart++) {
for(size_t diagshift = 0; diagshift < size-colstart ; diagshift++) {
size_t startPos = diagshift;
size_t endPos = colstart+diagshift;
for(size_t joinAt = startPos; joinAt < endPos ; joinAt++) {
float joinedScore = m_futureScore.GetScore(startPos, joinAt)
+ m_futureScore.GetScore(joinAt+1, endPos);
/* // uncomment to see the cell filling scheme
TRACE_ERR( "[" <<startPos<<","<<endPos<<"] <-? ["<<startPos<<","<<joinAt<<"]+["<<joinAt+1<<","<<endPos
<< "] (colstart: "<<colstart<<", diagshift: "<<diagshift<<")"<<endl);
*/
if (joinedScore > m_futureScore.GetScore(startPos, endPos))
m_futureScore.SetScore(startPos, endPos, joinedScore);
}
}
}
IFVERBOSE(3) {
int total = 0;
for(size_t row=0; row<size; row++) {
size_t maxSize = size - row;
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
for(size_t col=row; col<row+maxSize; col++) {
int count = GetTranslationOptionList(row, col).size();
TRACE_ERR( "translation options spanning from "
<< row <<" to "<< col <<" is "
<< count <<endl);
total += count;
}
}
TRACE_ERR( "translation options generated in total: "<< total << endl);
for(size_t row=0; row<size; row++)
for(size_t col=row; col<size; col++)
TRACE_ERR( "future cost from "<< row <<" to "<< col <<" is "<< m_futureScore.GetScore(row, col) <<endl);
}
}
/** Create all possible translations from the phrase tables
* for a particular input sentence. This implies applying all
* translation and generation steps. Also computes future cost matrix.
* \param decodeStepList list of decoding steps
* \param factorCollection input sentence with all factors
*/
void TranslationOptionCollection::CreateTranslationOptions()
{
// loop over all substrings of the source sentence, look them up
// in the phraseDictionary (which is the- possibly filtered-- phrase
// table loaded on initialization), generate TranslationOption objects
// for all phrases
// there may be multiple decoding graphs (factorizations of decoding)
const vector <DecodeGraph*> &decodeGraphList = m_system->GetDecodeGraphs();
const vector <size_t> &decodeGraphBackoff = m_system->GetDecodeGraphBackoff();
// length of the sentence
size_t size = m_source.GetSize();
// loop over all decoding graphs, each generates translation options
for (size_t graphInd = 0 ; graphInd < decodeGraphList.size() ; graphInd++) {
if (decodeGraphList.size() > 1) {
VERBOSE(3,"Creating translation options from decoding graph " << graphInd << endl);
}
const DecodeGraph &decodeGraph = *decodeGraphList[graphInd];
// generate phrases that start at startPos ...
for (size_t startPos = 0 ; startPos < size; startPos++) {
size_t maxSize = size - startPos; // don't go over end of sentence
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
// ... and that end at endPos
for (size_t endPos = startPos ; endPos < startPos + maxSize ; endPos++) {
if (graphInd > 0 && // only skip subsequent graphs
decodeGraphBackoff[graphInd] != 0 && // use of backoff specified
(endPos-startPos+1 >= decodeGraphBackoff[graphInd] || // size exceeds backoff limit or ...
m_collection[startPos][endPos-startPos].size() > 0)) { // no phrases found so far
VERBOSE(3,"No backoff to graph " << graphInd << " for span [" << startPos << ";" << endPos << "]" << endl);
// do not create more options
continue;
}
// create translation options for that range
CreateTranslationOptionsForRange( decodeGraph, startPos, endPos, true, graphInd);
}
}
}
VERBOSE(2,"Translation Option Collection\n " << *this << endl);
// Incorporate distributed lm scores.
IncorporateDLMScores();
ProcessUnknownWord();
// Prune
Prune();
Sort();
// future score matrix
CalcFutureScore();
// Cached lex reodering costs
CacheLexReordering();
// stateless feature scores
PreCalculateScores();
}
void TranslationOptionCollection::IncorporateDLMScores() {
// Build list of dlms.
const vector<const StatefulFeatureFunction*>& ffs =
m_system->GetStatefulFeatureFunctions();
std::map<int, LanguageModel*> dlm_ffs;
for (unsigned i = 0; i < ffs.size(); ++i) {
if (ffs[i]->GetScoreProducerDescription() == "DLM_5gram") {
dlm_ffs[i] = const_cast<LanguageModel*>(static_cast<const LanguageModel* const>(ffs[i]));
dlm_ffs[i]->SetFFStateIdx(i);
}
}
// Don't need to do anything if we don't have any distributed
// language models.
if (dlm_ffs.size() == 0) {
return;
}
// Iterate over all translation options in the collection.
std::vector< std::vector< TranslationOptionList > >::iterator start_iter;
for (start_iter = m_collection.begin();
start_iter != m_collection.end();
++start_iter) {
std::vector< TranslationOptionList >::iterator end_iter;
for (end_iter = (*start_iter).begin();
end_iter != (*start_iter).end();
++end_iter) {
std::vector< TranslationOption* >::iterator option_iter;
for (option_iter = (*end_iter).begin();
option_iter != (*end_iter).end();
++option_iter) {
// Get a handle on the current translation option.
TranslationOption* option = *option_iter;
std::map<int, LanguageModel*>::iterator dlm_iter;
for (dlm_iter = dlm_ffs.begin();
dlm_iter != dlm_ffs.end();
++dlm_iter) {
LanguageModel* dlm = (*dlm_iter).second;
float full_score;
float ngram_score;
size_t oov_count;
TargetPhrase& phrase =
const_cast<TargetPhrase&>(option->GetTargetPhrase());
dlm->CalcScoreFromCache(phrase,
full_score,
ngram_score,
oov_count);
ScoreComponentCollection& option_scores =
const_cast<ScoreComponentCollection&>(option->GetScoreBreakdown());
option_scores.Assign(dlm, ngram_score);
ScoreComponentCollection& phrase_scores =
const_cast<ScoreComponentCollection&>(phrase.GetScoreBreakdown());
phrase_scores.Assign(dlm, ngram_score);
float weighted_score = full_score * dlm->GetWeight();
phrase.SetFutureScore(phrase.GetFutureScore() + weighted_score);
}
}
}
}
}
void TranslationOptionCollection::Sort()
{
size_t size = m_source.GetSize();
for (size_t startPos = 0 ; startPos < size; ++startPos) {
size_t maxSize = size - startPos;
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
for (size_t endPos = startPos ; endPos < startPos + maxSize; ++endPos) {
TranslationOptionList &transOptList = GetTranslationOptionList(startPos, endPos);
std::sort(transOptList.begin(), transOptList.end(), CompareTranslationOption);
}
}
}
/** create translation options that exactly cover a specific input span.
* Called by CreateTranslationOptions() and ProcessUnknownWord()
* \param decodeGraph list of decoding steps
* \param factorCollection input sentence with all factors
* \param startPos first position in input sentence
* \param lastPos last position in input sentence
* \param adhereTableLimit whether phrase & generation table limits are adhered to
*/
void TranslationOptionCollection::CreateTranslationOptionsForRange(
const DecodeGraph &decodeGraph
, size_t startPos
, size_t endPos
, bool adhereTableLimit
, size_t graphInd)
{
if ((StaticData::Instance().GetXmlInputType() != XmlExclusive) || !HasXmlOptionsOverlappingRange(startPos,endPos)) {
Phrase *sourcePhrase = NULL; // can't initialise with substring, in case it's confusion network
// consult persistent (cross-sentence) cache for stored translation options
bool skipTransOptCreation = false
, useCache = StaticData::Instance().GetUseTransOptCache();
if (useCache) {
const WordsRange wordsRange(startPos, endPos);
sourcePhrase = new Phrase(m_source.GetSubString(wordsRange));
const TranslationOptionList *transOptList = StaticData::Instance().FindTransOptListInCache(decodeGraph, *sourcePhrase);
// is phrase in cache?
if (transOptList != NULL) {
skipTransOptCreation = true;
TranslationOptionList::const_iterator iterTransOpt;
for (iterTransOpt = transOptList->begin() ; iterTransOpt != transOptList->end() ; ++iterTransOpt) {
TranslationOption *transOpt = new TranslationOption(**iterTransOpt, wordsRange);
Add(transOpt);
}
}
} // useCache
if (!skipTransOptCreation) {
// partial trans opt stored in here
PartialTranslOptColl* oldPtoc = new PartialTranslOptColl;
size_t totalEarlyPruned = 0;
// initial translation step
list <const DecodeStep* >::const_iterator iterStep = decodeGraph.begin();
const DecodeStep &decodeStep = **iterStep;
static_cast<const DecodeStepTranslation&>(decodeStep).ProcessInitialTranslation
(m_system, m_source, *oldPtoc
, startPos, endPos, adhereTableLimit );
// do rest of decode steps
int indexStep = 0;
for (++iterStep ; iterStep != decodeGraph.end() ; ++iterStep) {
const DecodeStep &decodeStep = **iterStep;
PartialTranslOptColl* newPtoc = new PartialTranslOptColl;
// go thru each intermediate trans opt just created
const vector<TranslationOption*>& partTransOptList = oldPtoc->GetList();
vector<TranslationOption*>::const_iterator iterPartialTranslOpt;
for (iterPartialTranslOpt = partTransOptList.begin() ; iterPartialTranslOpt != partTransOptList.end() ; ++iterPartialTranslOpt) {
TranslationOption &inputPartialTranslOpt = **iterPartialTranslOpt;
decodeStep.Process(m_system, inputPartialTranslOpt
, decodeStep
, *newPtoc
, this
, adhereTableLimit);
}
// last but 1 partial trans not required anymore
totalEarlyPruned += newPtoc->GetPrunedCount();
delete oldPtoc;
oldPtoc = newPtoc;
indexStep++;
} // for (++iterStep
// add to fully formed translation option list
PartialTranslOptColl &lastPartialTranslOptColl = *oldPtoc;
const vector<TranslationOption*>& partTransOptList = lastPartialTranslOptColl.GetList();
vector<TranslationOption*>::const_iterator iterColl;
for (iterColl = partTransOptList.begin() ; iterColl != partTransOptList.end() ; ++iterColl) {
TranslationOption *transOpt = *iterColl;
transOpt->CalcScore(m_system);
Add(transOpt);
}
// storing translation options in persistent cache (kept across sentences)
if (useCache) {
if (partTransOptList.size() > 0) {
TranslationOptionList &transOptList = GetTranslationOptionList(startPos, endPos);
StaticData::Instance().AddTransOptListToCache(decodeGraph, *sourcePhrase, transOptList);
}
}
lastPartialTranslOptColl.DetachAll();
totalEarlyPruned += oldPtoc->GetPrunedCount();
delete oldPtoc;
// TRACE_ERR( "Early translation options pruned: " << totalEarlyPruned << endl);
} // if (!skipTransOptCreation)
if (useCache)
delete sourcePhrase;
} // if ((StaticData::Instance().GetXmlInputType() != XmlExclusive) || !HasXmlOptionsOverlappingRange(startPos,endPos))
if (graphInd == 0 && StaticData::Instance().GetXmlInputType() != XmlPassThrough && HasXmlOptionsOverlappingRange(startPos,endPos)) {
CreateXmlOptionsForRange(startPos, endPos);
}
}
/** Check if this range overlaps with any XML options. This doesn't need to be an exact match, only an overlap.
* by default, we don't support XML options. subclasses need to override this function.
* called by CreateTranslationOptionsForRange()
* \param startPos first position in input sentence
* \param lastPos last position in input sentence
* \param adhereTableLimit whether phrase & generation table limits are adhered to
*/
bool TranslationOptionCollection::HasXmlOptionsOverlappingRange(size_t, size_t) const
{
return false;
//not implemented for base class
}
/** Populates the current Collection with XML options exactly covering the range specified. Default implementation does nothing.
* called by CreateTranslationOptionsForRange()
* \param startPos first position in input sentence
* \param lastPos last position in input sentence
*/
void TranslationOptionCollection::CreateXmlOptionsForRange(size_t, size_t)
{
//not implemented for base class
};
/** add translation option to the list
* \param translationOption translation option to be added */
void TranslationOptionCollection::Add(TranslationOption *translationOption)
{
const WordsRange &coverage = translationOption->GetSourceWordsRange();
CHECK(coverage.GetEndPos() - coverage.GetStartPos() < m_collection[coverage.GetStartPos()].size());
m_collection[coverage.GetStartPos()][coverage.GetEndPos() - coverage.GetStartPos()].Add(translationOption);
}
TO_STRING_BODY(TranslationOptionCollection);
std::ostream& operator<<(std::ostream& out, const TranslationOptionCollection& coll)
{
size_t size = coll.GetSize();
for (size_t startPos = 0 ; startPos < size ; ++startPos) {
size_t maxSize = size - startPos;
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
for (size_t endPos = startPos ; endPos < startPos + maxSize ; ++endPos) {
const TranslationOptionList& fullList = coll.GetTranslationOptionList(startPos, endPos);
size_t sizeFull = fullList.size();
for (size_t i = 0; i < sizeFull; i++) {
out << *fullList.Get(i) << std::endl;
}
}
}
//std::vector< std::vector< TranslationOptionList > >::const_iterator i = coll.m_collection.begin();
//size_t j = 0;
//for (; i!=coll.m_collection.end(); ++i) {
//out << "s[" << j++ << "].size=" << i->size() << std::endl;
//}
return out;
}
const std::vector<Phrase*>& TranslationOptionCollection::GetUnknownSources() const
{
return m_unksrcs;
}
void TranslationOptionCollection::CacheLexReordering()
{
const vector<LexicalReordering*> &lexReorderingModels = m_system->GetReorderModels();
std::vector<LexicalReordering*>::const_iterator iterLexreordering;
size_t size = m_source.GetSize();
for (iterLexreordering = lexReorderingModels.begin() ; iterLexreordering != lexReorderingModels.end() ; ++iterLexreordering) {
LexicalReordering &lexreordering = **iterLexreordering;
for (size_t startPos = 0 ; startPos < size ; startPos++) {
size_t maxSize = size - startPos;
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
for (size_t endPos = startPos ; endPos < startPos + maxSize; endPos++) {
TranslationOptionList &transOptList = GetTranslationOptionList( startPos, endPos);
TranslationOptionList::iterator iterTransOpt;
for(iterTransOpt = transOptList.begin() ; iterTransOpt != transOptList.end() ; ++iterTransOpt) {
TranslationOption &transOpt = **iterTransOpt;
//Phrase sourcePhrase = m_source.GetSubString(WordsRange(startPos,endPos));
const Phrase *sourcePhrase = transOpt.GetSourcePhrase();
if (sourcePhrase) {
Scores score = lexreordering.GetProb(*sourcePhrase
, transOpt.GetTargetPhrase());
if (!score.empty())
transOpt.CacheScores(lexreordering, score);
}
}
}
}
}
}
void TranslationOptionCollection::PreCalculateScores()
{
//Figure out which features need to be precalculated
const vector<const StatelessFeatureFunction*>& sfs =
m_system->GetStatelessFeatureFunctions();
vector<const StatelessFeatureFunction*> precomputedFeatures;
for (unsigned i = 0; i < sfs.size(); ++i) {
if (sfs[i]->ComputeValueInTranslationOption() &&
!sfs[i]->ComputeValueInTranslationTable()) {
precomputedFeatures.push_back(sfs[i]);
}
}
//empty coverage vector
WordsBitmap coverage(m_source.GetSize());
if (precomputedFeatures.size()) {
//Go through translation options and precompute features
for (size_t i = 0; i < m_collection.size(); ++i) {
for (size_t j = 0; j < m_collection[i].size(); ++j) {
for (size_t k = 0; k < m_collection[i][j].size(); ++k) {
const TranslationOption* toption = m_collection[i][j].Get(k);
ScoreComponentCollection& breakdown = m_precalculatedScores[*toption];
PhraseBasedFeatureContext context(*toption, m_source);
for (size_t si = 0; si < precomputedFeatures.size(); ++si) {
precomputedFeatures[si]->Evaluate(context, &breakdown);
}
}
}
}
}
}
void TranslationOptionCollection::InsertPreCalculatedScores
(const TranslationOption& translationOption, ScoreComponentCollection* scoreBreakdown)
const
{
if (m_precalculatedScores.size()) {
boost::unordered_map<TranslationOption,ScoreComponentCollection>::const_iterator scoreIter =
m_precalculatedScores.find(translationOption);
if (scoreIter != m_precalculatedScores.end()) {
scoreBreakdown->PlusEquals(scoreIter->second);
} else {
TRACE_ERR("ERROR: " << translationOption << " missing from precalculation cache" << endl);
assert(0);
}
}
}
//! list of trans opt for a particular span
TranslationOptionList &TranslationOptionCollection::GetTranslationOptionList(size_t startPos, size_t endPos)
{
size_t maxSize = endPos - startPos;
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
CHECK(maxSize < m_collection[startPos].size());
return m_collection[startPos][maxSize];
}
const TranslationOptionList &TranslationOptionCollection::GetTranslationOptionList(size_t startPos, size_t endPos) const
{
size_t maxSize = endPos - startPos;
size_t maxSizePhrase = StaticData::Instance().GetMaxPhraseLength();
maxSize = std::min(maxSize, maxSizePhrase);
CHECK(maxSize < m_collection[startPos].size());
return m_collection[startPos][maxSize];
}
}
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