elim_keep()

M2_arrayintOrNull Matrix::elim_keep

(

int

nparts

)

const

Definition at line 1047 of file matrix.cpp.

{
  gc_vector<int> keep;
  const PolynomialRing *P = get_ring()->cast_to_PolynomialRing();
  if (P == nullptr)
    {
      ERROR("expected polynomial ring");
      return nullptr;
    }
  int nslots = P->getMonoid()->n_slots(nparts);
  for (int i = 0; i < n_cols(); i++)
    if (!P->vec_in_subring(nslots, elem(i))) keep.push_back(i);
  return stdvector_to_M2_arrayint<int>(keep);
}

References elem(), elim_keep(), ERROR, get_ring(), PolynomialRing::getMonoid(), n_cols(), Monoid::n_slots(), stdvector_to_M2_arrayint(), and Ring::vec_in_subring().

Referenced by elim_keep(), IM2_Matrix_keep_vars(), and minimal_lead_terms().