lead_coeff()

RingElement * RingElement::lead_coeff

(

const Ring *

coeffR

)

const

Definition at line 165 of file relem.cpp.

{
  if (is_zero())
    {
      return new RingElement(coeffR, coeffR->zero());
    }
  const PolynomialRing *P = R->cast_to_PolynomialRing();
  if (P != nullptr)
    {
      return new RingElement(coeffR, P->lead_logical_coeff(coeffR, val));
    }
  const M2FreeAlgebra* A = dynamic_cast<const M2FreeAlgebra*>(R);
  if (A != nullptr)
    {
      return new RingElement(coeffR, A->lead_coefficient(coeffR, val));
    }
  ERROR("expected polynomial ring");
  return nullptr;
}

References ERROR, is_zero(), M2FreeAlgebra::lead_coefficient(), PolynomialRing::lead_logical_coeff(), R, RingElement(), val, and Ring::zero().

Referenced by IM2_RingElement_lead_coeff().