Example #1
0
Val*
Val::
newIth(int ith, Val* oval, bool& stop)
{
  int ithc = oval->vec(ith);
  if(ithc > 0) stop = true;
  short nxtI = ithc +1;;
  //cerr<< "Wnt " << nxtI << "th var on pos " << ith << " of " << *oval<< endl;
  if(oval->wrd() >= 0) return NULL; //???;
  double ovalprob = oval->prob();
  //if(oval->status == TERMINALVAL) return NULL;
  Val* nval = ithBst(ith,oval->bsts()).next(nxtI);
  if(!nval) return NULL;
  double ovalcompprob = ithBst(ith, oval->bsts()).nth(ithc)->prob();
  double nprob = nval->prob();
  //cerr << "Its prob is " << nprob << endl;
  if(nprob < 0) return NULL;
  Val* ans = new Val(oval);
  ans->vec(ith) = nxtI;
  double frac = nprob/ovalcompprob;
  ans->prob() *= frac;
  assert(nxtI <= ithBst(ith,ans->bsts()).num());
  //cerr << "ith is " << ith << " " << ans->vec().size() << " "
  //   << ans->vec()[ith] << " " << frac << endl;
  //cerr << "The var is " << *ans << endl;
  //assert(ans->check());
  return ans;
}
Example #2
0
Bst&
MeChart::
bestParse(Item* itm, FullHist* h, Val* cval, Val* gcval, int cdir)
{
  curVal = cval;
  gcurVal = gcval;
  curDir = cdir;
  Bst& bst = recordedBP(itm, h);
  curVal = gcurVal = NULL;
  curDir = -1;
  if(bst.explored())
    {
      if(printDebug() > 19)
	{
	  prDp();
	  cerr << "already known bestParse(" << *itm << ", ...) has p = "
	       << bst.prob() << endl;
	}
      return bst;
    }
  if(printDebug() > 10)
    {
      prDp();
      cerr << "bestParse(" << *itm << ", ...)" << endl;
    }
  bst.explored() = true;  //David McClosky bug;
  int itermInt = itm->term()->toInt();
  PosMap& pm = itm->posAndheads();
  PosIter pi = pm.begin();
  ECString bestW;
  for( ; pi != pm.end() ; pi++ )
    {
      int posInt = (*pi).first;
      if(printDebug() > 16)
	{
	  prDp();
	  cerr << "consider Pos(" << *itm << ") = " << posInt << endl;
	}
      HeadMap& hm = (*pi).second;
      /* we are using collected counts for p(u|t) */
      float hposprob = 1;
      /* if we have reached a preterminal, then termInt == posInt
	 and p(posInt|termInt) == 1 */
      if( itermInt != posInt)
	{
          curVal = cval;
          gcurVal = gcval;
          curDir = cdir;
	  hposprob = meProb(posInt, h, UCALC); 
	  if(hposprob == 0) hposprob = .00001; //??? this can happen;
          curVal = gcurVal = NULL;
          curDir = -1;
	  if(printDebug() > 16)
	    {
	      prDp();
	      cerr <<  "p(pos) = " <<  hposprob << endl;
	    }
	}
      h->preTerm = posInt;
      HeadIter hi = hm.begin(); 
      for( ;hi != hm.end();hi++)
	{
	  const Wrd& subhw = (*hi).first;
	  int wrdInt = subhw.toInt();
	  ECString subh = subhw.lexeme();
	  if(printDebug() > 16)
	    {
	      prDp();
	      cerr << "consider head(" << *itm << ") = " << subh << endl;
	    }
	  float hprob = 0;
	  if(wrdInt >= 0 && wrdInt <= lastKnownWord)
	    {
	      hprob = pCapgt(&subhw,posInt); 
	      hprob *= (1 - pHugt(posInt)); 
              curVal = cval;
              gcurVal = gcval;
              curDir = cdir;
	      float hprob2 = meHeadProb(wrdInt, h);
              curVal = gcurVal = NULL;
              curDir = -1;
	      hprob *= hprob2;
	      if(hprob < 0)
		{
		  cerr << posInt << " " << pHugt(posInt) <<" "<<hprob2 << endl;
		  assert(hprob >=0);
		}
	    }
	  //hprob can be zero if lower case NNPS.
	  if(wrdInt > lastKnownWord || hprob == 0)
	    {
	      hprob = psutt(&subhw,posInt);
	    }
	  if(printDebug() > 16)
	    {
	      prDp();
	      cerr << "p(hd) = "<< hprob << endl;
	    }
	  float hhprob = (hposprob * hprob);
	  if(hhprob < 0)
	    {
	      cerr << hposprob << " " << hprob << endl;
	      assert(hhprob >= 0);
	    }
	  h->hd = &subhw;
	  Bst&  
	    bst2 = bestParseGivenHead(posInt,subhw,itm,h,(*hi).second,cval,gcval);
          if(bst2.empty()) continue;
          Val* nval = new Val();
	  Val* oldval0 = bst2.nth(0);
          nval->prob() = oldval0->prob()*hhprob;
          nval->bsts().push_back(&bst2);
	  nval->status = EXTRAVAL;
          bst.push(nval);
          bst.sum() += bst2.sum()*hhprob;
	}
    }
  Val* nbest = bst.pop();
  if(nbest) bst.addnth(nbest);
  if(printDebug() > 10)
    {
      prDp();
      cerr << "Bestp for " << *itm << " = " << bst.prob() <<endl;
    }
  return bst;
}