Example #1
0
InputPath::
InputPath(const Phrase &phrase, const NonTerminalSet &sourceNonTerms,
          const WordsRange &range, const InputPath *prevNode,
          const ScorePair *inputScore)
  :m_prevPath(prevNode)
  ,m_phrase(phrase)
  ,m_range(range)
  ,m_inputScore(inputScore)
  ,m_nextNode(1)
  ,m_sourceNonTerms(sourceNonTerms)
  ,m_sourceNonTermArray(FactorCollection::Instance().GetNumNonTerminals(), false)
{
  for (NonTerminalSet::const_iterator iter = sourceNonTerms.begin(); iter != sourceNonTerms.end(); ++iter) {
    size_t idx = (*iter)[0]->GetId();
    m_sourceNonTermArray[idx] = true;
  }

  //cerr << "phrase=" << phrase << " m_inputScore=" << *m_inputScore << endl;

}
// Given a partial rule application ending at startPos-1 and given the sets of
// source and target non-terminals covering the span [startPos, endPos],
// determines the full or partial rule applications that can be produced through
// extending the current rule application by a single non-terminal.
void ChartRuleLookupManagerMemory::ExtendPartialRuleApplication(
    const PhraseDictionaryNodeSCFG & node,
    const WordConsumed *prevWordConsumed,
    size_t startPos,
    size_t endPos,
    size_t stackInd,
    const NonTerminalSet & sourceNonTerms,
    const NonTerminalSet & targetNonTerms,
    ProcessedRuleColl & processedRuleColl)
{
    const PhraseDictionaryNodeSCFG::NonTerminalMap & nonTermMap =
        node.GetNonTerminalMap();

    const size_t numChildren = nonTermMap.size();
    if (numChildren == 0)
    {
        return;
    }
    const size_t numSourceNonTerms = sourceNonTerms.size();
    const size_t numTargetNonTerms = targetNonTerms.size();
    const size_t numCombinations = numSourceNonTerms * numTargetNonTerms;

    // We can search by either:
    //   1. Enumerating all possible source-target NT pairs that are valid for
    //      the span and then searching for matching children in the node,
    // or
    //   2. Iterating over all the NT children in the node, searching
    //      for each source and target NT in the span's sets.
    // We'll do whichever minimises the number of lookups:
    if (numCombinations <= numChildren*2)
    {
        NonTerminalSet::const_iterator p = sourceNonTerms.begin();
        NonTerminalSet::const_iterator sEnd = sourceNonTerms.end();
        for (; p != sEnd; ++p)
        {
            const Word & sourceNonTerm = *p;
            NonTerminalSet::const_iterator q = targetNonTerms.begin();
            NonTerminalSet::const_iterator tEnd = targetNonTerms.end();
            for (; q != tEnd; ++q)
            {
                const Word & targetNonTerm = *q;
                const PhraseDictionaryNodeSCFG * child =
                    node.GetChild(sourceNonTerm, targetNonTerm);
                if (child == NULL)
                {
                    continue;
                }
                WordConsumed * wc = new WordConsumed(startPos, endPos,
                                                     targetNonTerm,
                                                     prevWordConsumed);
                ProcessedRule * rule = new ProcessedRule(*child, wc);
                processedRuleColl.Add(stackInd, rule);
            }
        }
    }
    else
    {
        PhraseDictionaryNodeSCFG::NonTerminalMap::const_iterator p;
        PhraseDictionaryNodeSCFG::NonTerminalMap::const_iterator end =
                                                            nonTermMap.end();
        for (p = nonTermMap.begin(); p != end; ++p)
        {
            const PhraseDictionaryNodeSCFG::NonTerminalMapKey & key = p->first;
            const Word & sourceNonTerm = key.first;
            if (sourceNonTerms.find(sourceNonTerm) == sourceNonTerms.end())
            {
                continue;
            }
            const Word & targetNonTerm = key.second;
            if (targetNonTerms.find(targetNonTerm) == targetNonTerms.end())
            {
                continue;
            }
            const PhraseDictionaryNodeSCFG & child = p->second;
            WordConsumed * wc = new WordConsumed(startPos, endPos,
                                                 targetNonTerm,
                                                 prevWordConsumed);
            ProcessedRule * rule = new ProcessedRule(child, wc);
            processedRuleColl.Add(stackInd, rule);
        }
    }
}