computeRank()

void SchreyerFrame::computeRank ( int slanted_degree, int lev )

private

Definition at line 964 of file res-schreyer-frame.cpp.

{
  //  std::cout << "computeRank(" << slanted_degree << "," << lev << ")" <<
  //  std::endl;
  int& status = mComputationStatus.entry(slanted_degree, lev);
  if (status == 0) return;  // Nothing here
  if (status == 1)
    {
      fillinSyzygies(slanted_degree, lev);
    }
  if (status == 3) return;  // already done
  int rk = rank(slanted_degree, lev);
  if (rk > 0)
    {
      mBettiMinimal.entry(slanted_degree, lev) -= rk;
      if (slanted_degree <= mHiSlantedDegree and lev > 0)
        mBettiMinimal.entry(slanted_degree + 1, lev - 1) -= rk;
 
      // std::cout << "--- minimal betti after computeRank: " << slanted_degree << " " << lev << std::endl;
      // mBettiMinimal.output();
    }
  status = 3;
}

References fillinSyzygies(), mBettiMinimal, mComputationStatus, and rank().

Referenced by computeRanks(), and minimalBettiNumbers().