mosesdecoder/mira/Decoder.cpp
2012-11-14 14:18:53 +00:00

394 lines
16 KiB
C++

/***********************************************************************
Moses - factored phrase-based language decoder
Copyright (C) 2009 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 "Decoder.h"
#include "moses/Manager.h"
#include "moses/ChartManager.h"
#include "moses/Sentence.h"
#include "moses/InputType.h"
#include "moses/TranslationSystem.h"
#include "moses/Phrase.h"
#include "moses/TrellisPathList.h"
#include "moses/ChartTrellisPathList.h"
#include "moses/ChartTrellisPath.h"
using namespace std;
using namespace Moses;
namespace Mira {
/**
* Allocates a char* and copies string into it.
**/
static char* strToChar(const string& s) {
char* c = new char[s.size()+1];
strcpy(c,s.c_str());
return c;
}
MosesDecoder::MosesDecoder(const string& inifile, int debuglevel, int argc, vector<string> decoder_params)
: m_manager(NULL) {
static int BASE_ARGC = 8;
Parameter* params = new Parameter();
char ** mosesargv = new char*[BASE_ARGC + argc];
mosesargv[0] = strToChar("-f");
mosesargv[1] = strToChar(inifile);
mosesargv[2] = strToChar("-v");
stringstream dbgin;
dbgin << debuglevel;
mosesargv[3] = strToChar(dbgin.str());
mosesargv[4] = strToChar("-use-persistent-cache");
mosesargv[5] = strToChar("0");
mosesargv[6] = strToChar("-persistent-cache-size");
mosesargv[7] = strToChar("0");
for (int i = 0; i < argc; ++i) {
char *cstr = &(decoder_params[i])[0];
mosesargv[BASE_ARGC + i] = cstr;
}
if (!params->LoadParam(BASE_ARGC + argc,mosesargv)) {
cerr << "Loading static data failed, exit." << endl;
exit(1);
}
StaticData::LoadDataStatic(params, "mira");
for (int i = 0; i < BASE_ARGC; ++i) {
delete[] mosesargv[i];
}
delete[] mosesargv;
const StaticData &staticData = StaticData::Instance();
m_bleuScoreFeature = staticData.GetBleuScoreFeature();
}
void MosesDecoder::cleanup(bool chartDecoding) {
delete m_manager;
if (chartDecoding)
delete m_chartManager;
else
delete m_sentence;
}
vector< vector<const Word*> > MosesDecoder::getNBest(const std::string& source,
size_t sentenceid,
size_t nBestSize,
float bleuObjectiveWeight,
float bleuScoreWeight,
vector< ScoreComponentCollection>& featureValues,
vector< float>& bleuScores,
vector< float>& modelScores,
size_t numReturnedTranslations,
bool realBleu,
bool distinct,
bool avgRefLength,
size_t rank,
size_t epoch,
string filename)
{
StaticData &staticData = StaticData::InstanceNonConst();
bool chartDecoding = (staticData.GetSearchAlgorithm() == ChartDecoding);
initialize(staticData, source, sentenceid, bleuObjectiveWeight, bleuScoreWeight, avgRefLength, chartDecoding);
const TranslationSystem& system = staticData.GetTranslationSystem(TranslationSystem::DEFAULT);
// run the decoder
if (chartDecoding) {
return runChartDecoder(source, sentenceid, nBestSize, bleuObjectiveWeight, bleuScoreWeight,
featureValues, bleuScores, modelScores, numReturnedTranslations, realBleu, distinct, rank, epoch,
system);
}
else {
SearchAlgorithm search = staticData.GetSearchAlgorithm();
return runDecoder(source, sentenceid, nBestSize, bleuObjectiveWeight, bleuScoreWeight,
featureValues, bleuScores, modelScores, numReturnedTranslations, realBleu, distinct, rank, epoch,
search, system, filename);
}
}
vector< vector<const Word*> > MosesDecoder::runDecoder(const std::string& source,
size_t sentenceid,
size_t nBestSize,
float bleuObjectiveWeight,
float bleuScoreWeight,
vector< ScoreComponentCollection>& featureValues,
vector< float>& bleuScores,
vector< float>& modelScores,
size_t numReturnedTranslations,
bool realBleu,
bool distinct,
size_t rank,
size_t epoch,
SearchAlgorithm& search,
const TranslationSystem& system,
string filename) {
// run the decoder
m_manager = new Moses::Manager(0,*m_sentence, search, &system);
m_manager->ProcessSentence();
TrellisPathList nBestList;
m_manager->CalcNBest(nBestSize, nBestList, distinct);
// optionally print nbest to file (to extract scores and features.. currently just for sentence bleu scoring)
if (filename != "") {
ofstream out(filename.c_str());
if (!out) {
ostringstream msg;
msg << "Unable to open " << filename;
throw runtime_error(msg.str());
}
// TODO: handle sentence id (for now always 0)
//OutputNBest(out, nBestList, StaticData::Instance().GetOutputFactorOrder(),m_manager->GetTranslationSystem(), 0, false);
out.close();
}
// read off the feature values and bleu scores for each sentence in the nbest list
Moses::TrellisPathList::const_iterator iter;
for (iter = nBestList.begin() ; iter != nBestList.end() ; ++iter) {
const Moses::TrellisPath &path = **iter;
featureValues.push_back(path.GetScoreBreakdown());
float bleuScore, dynBleuScore, realBleuScore;
if (realBleu) realBleuScore = m_bleuScoreFeature->CalculateBleu(path.GetTargetPhrase());
else dynBleuScore = getBleuScore(featureValues.back());
bleuScore = realBleu ? realBleuScore : dynBleuScore;
bleuScores.push_back(bleuScore);
//std::cout << "Score breakdown: " << path.GetScoreBreakdown() << endl;
float scoreWithoutBleu = path.GetTotalScore() - (bleuObjectiveWeight * bleuScoreWeight * bleuScore);
modelScores.push_back(scoreWithoutBleu);
if (iter != nBestList.begin())
cerr << endl;
cerr << "Rank " << rank << ", epoch " << epoch << ", \"" << path.GetTargetPhrase() << "\", score: "
<< scoreWithoutBleu << ", Bleu: " << bleuScore << ", total: " << path.GetTotalScore();
if (m_bleuScoreFeature->Enabled() && realBleu)
cerr << " (d-bleu: " << dynBleuScore << ", r-bleu: " << realBleuScore << ") ";
// set bleu score to zero in the feature vector since we do not want to optimise its weight
setBleuScore(featureValues.back(), 0);
}
// prepare translations to return
vector< vector<const Word*> > translations;
for (size_t i=0; i < numReturnedTranslations && i < nBestList.GetSize(); ++i) {
const TrellisPath &path = nBestList.at(i);
Phrase phrase = path.GetTargetPhrase();
vector<const Word*> translation;
for (size_t pos = 0; pos < phrase.GetSize(); ++pos) {
const Word &word = phrase.GetWord(pos);
Word *newWord = new Word(word);
translation.push_back(newWord);
}
translations.push_back(translation);
}
return translations;
}
vector< vector<const Word*> > MosesDecoder::runChartDecoder(const std::string& source,
size_t sentenceid,
size_t nBestSize,
float bleuObjectiveWeight,
float bleuScoreWeight,
vector< ScoreComponentCollection>& featureValues,
vector< float>& bleuScores,
vector< float>& modelScores,
size_t numReturnedTranslations,
bool realBleu,
bool distinct,
size_t rank,
size_t epoch,
const TranslationSystem& system) {
// run the decoder
m_chartManager = new ChartManager(*m_sentence, &system);
m_chartManager->ProcessSentence();
ChartTrellisPathList nBestList;
m_chartManager->CalcNBest(nBestSize, nBestList, distinct);
// read off the feature values and bleu scores for each sentence in the nbest list
ChartTrellisPathList::const_iterator iter;
for (iter = nBestList.begin() ; iter != nBestList.end() ; ++iter) {
const Moses::ChartTrellisPath &path = **iter;
featureValues.push_back(path.GetScoreBreakdown());
float bleuScore, dynBleuScore, realBleuScore;
dynBleuScore = getBleuScore(featureValues.back());
realBleuScore = m_bleuScoreFeature->CalculateBleu(path.GetOutputPhrase());
bleuScore = realBleu ? realBleuScore : dynBleuScore;
bleuScores.push_back(bleuScore);
//std::cout << "Score breakdown: " << path.GetScoreBreakdown() << endl;
float scoreWithoutBleu = path.GetTotalScore() - (bleuObjectiveWeight * bleuScoreWeight * bleuScore);
modelScores.push_back(scoreWithoutBleu);
if (iter != nBestList.begin())
cerr << endl;
cerr << "Rank " << rank << ", epoch " << epoch << ", \"" << path.GetOutputPhrase() << "\", score: "
<< scoreWithoutBleu << ", Bleu: " << bleuScore << ", total: " << path.GetTotalScore();
if (m_bleuScoreFeature->Enabled() && realBleu)
cerr << " (d-bleu: " << dynBleuScore << ", r-bleu: " << realBleuScore << ") ";
// set bleu score to zero in the feature vector since we do not want to optimise its weight
setBleuScore(featureValues.back(), 0);
}
// prepare translations to return
vector< vector<const Word*> > translations;
for (iter = nBestList.begin() ; iter != nBestList.end() ; ++iter) {
const ChartTrellisPath &path = **iter;
Phrase phrase = path.GetOutputPhrase();
vector<const Word*> translation;
for (size_t pos = 0; pos < phrase.GetSize(); ++pos) {
const Word &word = phrase.GetWord(pos);
Word *newWord = new Word(word);
translation.push_back(newWord);
}
translations.push_back(translation);
}
return translations;
}
void MosesDecoder::outputNBestList(const std::string& source, size_t sentenceid,
size_t nBestSize, float bleuObjectiveWeight, float bleuScoreWeight,
bool distinctNbest, bool avgRefLength, string filename, ofstream& streamOut) {
StaticData &staticData = StaticData::InstanceNonConst();
bool chartDecoding = (staticData.GetSearchAlgorithm() == ChartDecoding);
initialize(staticData, source, sentenceid, bleuObjectiveWeight, bleuScoreWeight, avgRefLength, chartDecoding);
const TranslationSystem& system = staticData.GetTranslationSystem(TranslationSystem::DEFAULT);
if (chartDecoding) {
m_chartManager = new ChartManager(*m_sentence, &system);
m_chartManager->ProcessSentence();
ChartTrellisPathList nBestList;
m_chartManager->CalcNBest(nBestSize, nBestList, distinctNbest);
cerr << "generate nbest list " << filename << endl;
cerr << "not implemented.." << endl;
exit(1);
if (filename != "") {
ofstream out(filename.c_str());
if (!out) {
ostringstream msg;
msg << "Unable to open " << filename;
throw runtime_error(msg.str());
}
// TODO: handle sentence id (for now always 0)
// OutputNBestList(const ChartTrellisPathList &nBestList, const ChartHypothesis *bestHypo, const TranslationSystem* system, long translationId, false)
// OutputNBest(out, nBestList, StaticData::Instance().GetOutputFactorOrder(),m_manager->GetTranslationSystem(), 0, false);
out.close();
}
else {
// OutputNBest(streamOut, nBestList, StaticData::Instance().GetOutputFactorOrder(),m_manager->GetTranslationSystem(), sentenceid, false);
}
}
else {
// run the decoder
m_manager = new Moses::Manager(0,*m_sentence, staticData.GetSearchAlgorithm(), &system);
m_manager->ProcessSentence();
TrellisPathList nBestList;
m_manager->CalcNBest(nBestSize, nBestList, distinctNbest);
if (filename != "") {
ofstream out(filename.c_str());
if (!out) {
ostringstream msg;
msg << "Unable to open " << filename;
throw runtime_error(msg.str());
}
// TODO: handle sentence id (for now always 0)
//OutputNBest(out, nBestList, StaticData::Instance().GetOutputFactorOrder(),m_manager->GetTranslationSystem(), 0, false);
out.close();
}
else {
//OutputNBest(streamOut, nBestList, StaticData::Instance().GetOutputFactorOrder(),m_manager->GetTranslationSystem(), sentenceid, false);
streamOut.flush();
}
}
}
void MosesDecoder::initialize(StaticData& staticData, const std::string& source, size_t sentenceid,
float bleuObjectiveWeight, float bleuScoreWeight, bool avgRefLength, bool chartDecoding) {
m_sentence = new Sentence();
stringstream in(source + "\n");
const std::vector<FactorType> &inputFactorOrder = staticData.GetInputFactorOrder();
m_sentence->Read(in,inputFactorOrder);
// set weight of BleuScoreFeature
//cerr << "Reload Bleu feature weight: " << bleuObjectiveWeight*bleuScoreWeight << " (" << bleuObjectiveWeight << "*" << bleuScoreWeight << ")" << endl;
staticData.ReLoadBleuScoreFeatureParameter(bleuObjectiveWeight*bleuScoreWeight);
m_bleuScoreFeature->SetCurrSourceLength((*m_sentence).GetSize());
if (chartDecoding)
m_bleuScoreFeature->SetCurrNormSourceLength((*m_sentence).GetSize()-2);
else
m_bleuScoreFeature->SetCurrNormSourceLength((*m_sentence).GetSize());
if (avgRefLength)
m_bleuScoreFeature->SetCurrAvgRefLength(sentenceid);
else
m_bleuScoreFeature->SetCurrShortestRefLength(sentenceid);
m_bleuScoreFeature->SetCurrReferenceNgrams(sentenceid);
}
float MosesDecoder::getBleuScore(const ScoreComponentCollection& scores) {
return scores.GetScoreForProducer(m_bleuScoreFeature);
}
void MosesDecoder::setBleuScore(ScoreComponentCollection& scores, float bleu) {
scores.Assign(m_bleuScoreFeature, bleu);
}
ScoreComponentCollection MosesDecoder::getWeights() {
return StaticData::Instance().GetAllWeights();
}
void MosesDecoder::setWeights(const ScoreComponentCollection& weights) {
StaticData::InstanceNonConst().SetAllWeights(weights);
}
void MosesDecoder::updateHistory(const vector<const Word*>& words) {
m_bleuScoreFeature->UpdateHistory(words);
}
void MosesDecoder::updateHistory(const vector< vector< const Word*> >& words, vector<size_t>& sourceLengths, vector<size_t>& ref_ids, size_t rank, size_t epoch) {
m_bleuScoreFeature->UpdateHistory(words, sourceLengths, ref_ids, rank, epoch);
}
void MosesDecoder::printBleuFeatureHistory(std::ostream& out) {
m_bleuScoreFeature->PrintHistory(out);
}
size_t MosesDecoder::getClosestReferenceLength(size_t ref_id, int hypoLength) {
return m_bleuScoreFeature->GetClosestRefLength(ref_id, hypoLength);
}
size_t MosesDecoder::getShortestReferenceIndex(size_t ref_id) {
return m_bleuScoreFeature->GetShortestRefIndex(ref_id);
}
void MosesDecoder::setBleuParameters(bool disable, bool sentenceBleu, bool scaleByInputLength, bool scaleByAvgInputLength,
bool scaleByInverseLength, bool scaleByAvgInverseLength,
float scaleByX, float historySmoothing, size_t scheme, bool simpleHistoryBleu) {
m_bleuScoreFeature->SetBleuParameters(disable, sentenceBleu, scaleByInputLength, scaleByAvgInputLength,
scaleByInverseLength, scaleByAvgInverseLength,
scaleByX, historySmoothing, scheme, simpleHistoryBleu);
}
}