Example #1
0
void ChartParser::Create(const Range &range, ChartParserCallback &to)
{
  assert(m_decodeGraphList.size() == m_ruleLookupManagers.size());

  std::vector <DecodeGraph*>::const_iterator iterDecodeGraph;
  std::vector <ChartRuleLookupManager*>::const_iterator iterRuleLookupManagers = m_ruleLookupManagers.begin();
  for (iterDecodeGraph = m_decodeGraphList.begin(); iterDecodeGraph != m_decodeGraphList.end(); ++iterDecodeGraph, ++iterRuleLookupManagers) {
    const DecodeGraph &decodeGraph = **iterDecodeGraph;
    assert(decodeGraph.GetSize() == 1);
    ChartRuleLookupManager &ruleLookupManager = **iterRuleLookupManagers;
    size_t maxSpan = decodeGraph.GetMaxChartSpan();
    size_t last = m_source.GetSize()-1;
    if (maxSpan != 0) {
      last = min(last, range.GetStartPos()+maxSpan);
    }
    if (maxSpan == 0 || range.GetNumWordsCovered() <= maxSpan) {
      const InputPath &inputPath = GetInputPath(range);
      ruleLookupManager.GetChartRuleCollection(inputPath, last, to);
    }
  }

  if (range.GetNumWordsCovered() == 1 && range.GetStartPos() != 0 && range.GetStartPos() != m_source.GetSize()-1) {
    bool alwaysCreateDirectTranslationOption = StaticData::Instance().IsAlwaysCreateDirectTranslationOption();
    if (to.Empty() || alwaysCreateDirectTranslationOption) {
      // create unknown words for 1 word coverage where we don't have any trans options
      const Word &sourceWord = m_source.GetWord(range.GetStartPos());
      m_unknown.Process(sourceWord, range, to);
    }
  }
}
float
DistortionScoreProducer::
CalculateDistortionScore(const Hypothesis& hypo,
                         const Range &prev, const Range &curr, const int FirstGap)
{
  // if(!StaticData::Instance().UseEarlyDistortionCost()) {
  if(!hypo.GetManager().options()->reordering.use_early_distortion_cost) {
    return - (float) hypo.GetInput().ComputeDistortionDistance(prev, curr);
  } // else {

  /* Pay distortion score as soon as possible, from Moore and Quirk MT Summit 2007
     Definitions:
     S   : current source range
     S'  : last translated source phrase range
     S'' : longest fully-translated initial segment
  */

  int prefixEndPos = (int)FirstGap-1;
  if((int)FirstGap==-1)
    prefixEndPos = -1;

  // case1: S is adjacent to S'' => return 0
  if ((int) curr.GetStartPos() == prefixEndPos+1) {
    IFVERBOSE(4) std::cerr<< "MQ07disto:case1" << std::endl;
    return 0;
  }

  // case2: S is to the left of S' => return 2(length(S))
  if ((int) curr.GetEndPos() < (int) prev.GetEndPos()) {
    IFVERBOSE(4) std::cerr<< "MQ07disto:case2" << std::endl;
    return (float) -2*(int)curr.GetNumWordsCovered();
  }

  // case3: S' is a subsequence of S'' => return 2(nbWordBetween(S,S'')+length(S))
  if ((int) prev.GetEndPos() <= prefixEndPos) {
    IFVERBOSE(4) std::cerr<< "MQ07disto:case3" << std::endl;
    int z = (int)curr.GetStartPos()-prefixEndPos - 1;
    return (float) -2*(z + (int)curr.GetNumWordsCovered());
  }

  // case4: otherwise => return 2(nbWordBetween(S,S')+length(S))
  IFVERBOSE(4) std::cerr<< "MQ07disto:case4" << std::endl;
  return (float) -2*((int)curr.GetNumWordsBetween(prev) + (int)curr.GetNumWordsCovered());

}
Example #3
0
Phrase Phrase::GetSubString(const Range &range) const
{
  Phrase retPhrase(range.GetNumWordsCovered());

  for (size_t currPos = range.GetStartPos() ; currPos <= range.GetEndPos() ; currPos++) {
    Word &word = retPhrase.AddWord();
    word = GetWord(currPos);
  }

  return retPhrase;
}
Example #4
0
Phrase Phrase::GetSubString(const Range &range, FactorType factorType) const
{
  Phrase retPhrase(range.GetNumWordsCovered());

  for (size_t currPos = range.GetStartPos() ; currPos <= range.GetEndPos() ; currPos++) {
    const Factor* f = GetFactor(currPos, factorType);
    Word &word = retPhrase.AddWord();
    word.SetFactor(factorType, f);
  }

  return retPhrase;
}