make() [3/3]

const Matrix * Matrix::make ( const MonomialIdeal * mi )

static

Definition at line 281 of file matrix.cpp.

{
  const PolynomialRing *P = mi->get_ring()->cast_to_PolynomialRing();
  if (P == nullptr)
    {
      ERROR("expected a matrix over a polynomial ring");
      return nullptr;
    }
  const Monoid *M = P->getMonoid();
  monomial mon = M->make_one();
 
  MatrixConstructor mat(P->make_FreeModule(1), mi->size());
  int next = 0;
  for (auto i = mi->beginAtLast(); i != mi->end(); --i)  // TODO MES: should go from last() via --i to end()...
    {
      M->from_varpower(i->monom().data(), mon);
      ring_elem f =
          P->make_flat_term(P->getCoefficientRing()->from_long(1), mon);
      mat.set_entry(0, next++, f);
    }
  M->remove(mon);
 
  mat.compute_column_degrees();
  return mat.to_matrix();
}

References MonomialIdeal::beginAtLast(), PolynomialRing::cast_to_PolynomialRing(), MatrixConstructor::compute_column_degrees(), MonomialIdeal::end(), ERROR, Ring::from_long(), Monoid::from_varpower(), MonomialIdeal::get_ring(), PolynomialRing::getCoefficientRing(), PolynomialRing::getMonoid(), make(), PolynomialRing::make_flat_term(), Ring::make_FreeModule(), Monoid::make_one(), Matrix(), MatrixConstructor, monomial, Monoid::remove(), MatrixConstructor::set_entry(), MonomialIdeal::size(), and MatrixConstructor::to_matrix().