setSchreyerOrder()

void SchreyerFrame::setSchreyerOrder

(

int

lev

)

Definition at line 572 of file res-schreyer-frame.cpp.

{
  auto& myframe = level(lev);
  auto& myorder = schreyerOrder(lev);
  myorder.mTieBreaker.resize(myframe.size());
  //  std::cout << "setSchreyerOrder: entering, lev=" << lev << ", nelems=" <<
  //  myframe.size() << std::endl;
  if (lev == 0)
    {
      for (component_index i = 0; i < myorder.mTieBreaker.size(); i++)
        myorder.mTieBreaker[i] = i;
      return;
    }
 
  auto& prevorder = schreyerOrder(lev - 1);
  long* tiebreakers = new long[myframe.size()];
 
  auto n_frame_elems = myframe.size();
  for (component_index i = 0; i < n_frame_elems; i++)
    {
      component_index comp = monoid().get_component(myframe[i].mMonom);
      tiebreakers[i] = i + n_frame_elems * prevorder.mTieBreaker[comp];
    }
  std::stable_sort(tiebreakers, tiebreakers + n_frame_elems);
 
  for (component_index i = 0; i < n_frame_elems; i++)
    {
      myorder.mTieBreaker[tiebreakers[i] % n_frame_elems] = i;
    }
  delete[] tiebreakers;
  //  std::cout << "  setSchreyerOrder: exiting, lev=" << lev << std::endl;
}

References ResMonoidDense::get_component(), level(), monoid(), and schreyerOrder().

Referenced by computeNextLevel(), and endLevel().