Exemple #1
0
void SimplexDecisionProcedure::shrinkInfeasFunc(TimerStat& timer, ArithVar inf, const ArithVarVec& dropped){
  TimerStat::CodeTimer codeTimer(timer);
  for(ArithVarVec::const_iterator i=dropped.begin(), i_end = dropped.end(); i != i_end; ++i){
    ArithVar back = *i;

    int focusSgn = d_errorSet.focusSgn(back);
    Rational chg(-focusSgn);

    d_linEq.substitutePlusTimesConstant(inf, back, chg);
  }
}
Exemple #2
0
ArithVar SimplexDecisionProcedure::constructInfeasiblityFunction(TimerStat& timer, const ArithVarVec& set){
  Debug("constructInfeasiblityFunction") << "constructInfeasiblityFunction start" << endl;

  TimerStat::CodeTimer codeTimer(timer);
  Assert(!d_errorSet.focusEmpty());
  Assert(debugIsASet(set));
  
  ArithVar inf = requestVariable();
  Assert(inf != ARITHVAR_SENTINEL);

  std::vector<Rational> coeffs;
  std::vector<ArithVar> variables;

  for(ArithVarVec::const_iterator iter = set.begin(), iend = set.end(); iter != iend; ++iter){
    ArithVar e = *iter;

    Assert(d_tableau.isBasic(e));
    Assert(!d_variables.assignmentIsConsistent(e));

    int sgn = d_errorSet.getSgn(e);
    Assert(sgn == -1 || sgn == 1);
    const Rational& violatedCoeff = sgn < 0 ? d_negOne : d_posOne;
    coeffs.push_back(violatedCoeff);
    variables.push_back(e);

    Debug("constructInfeasiblityFunction") << violatedCoeff << " " << e << endl;

  }
  d_tableau.addRow(inf, coeffs, variables);
  DeltaRational newAssignment = d_linEq.computeRowValue(inf, false);
  d_variables.setAssignment(inf, newAssignment);

  //d_linEq.trackVariable(inf);
  d_linEq.trackRowIndex(d_tableau.basicToRowIndex(inf));

  Debug("constructInfeasiblityFunction") << inf << " " << newAssignment << endl;
  Debug("constructInfeasiblityFunction") << "constructInfeasiblityFunction done" << endl;
  return inf;
}