list_form()

engine_RawArrayPairOrNull SchurRing2::list_form	(	const Ring *	coeffR,
		const ring_elem	f ) const

Definition at line 682 of file schur2.cpp.

{
  if (coeffR != coefficientRing)
    {
      ERROR("expected coefficient ring of Schur ring");
      return nullptr;
    }
  const schur_poly *f1 = f.get_schur_poly();
  int n = static_cast<int>(f1->size());  // this is here because the lengths of
                                         // arrays for M3 front end use int as
                                         // length field.
  engine_RawMonomialArray monoms =
      GETMEM(engine_RawMonomialArray, sizeofarray(monoms, n));
  engine_RawRingElementArray coeffs =
      GETMEM(engine_RawRingElementArray, sizeofarray(coeffs, n));
  monoms->len = n;
  coeffs->len = n;
  engine_RawArrayPair result = newitem(struct engine_RawArrayPair_struct);
  result->monoms = monoms;
  result->coeffs = coeffs;
 
  // Loop through the terms
  gc_vector<int> vp;
  schur_poly::iterator i = f1->begin();
  for (int next = 0; next < n; ++i, ++next)
    {
      coeffs->array[next] =
          RingElement::make_raw(coefficientRing, i.getCoefficient());
      to_varpower(i.getMonomial(), vp);
      monoms->array[next] = EngineMonomial::make(vp.data());
      vp.resize(0);
    }
  return result;
}

References schur_poly::begin(), coefficientRing, ERROR, ring_elem::get_schur_poly(), schur_poly_iterator::getCoefficient(), GETMEM, schur_poly_iterator::getMonomial(), EngineMonomial::make(), RingElement::make_raw(), newitem, result(), Ring::Ring(), schur_poly::size(), sizeofarray, and to_varpower().

Referenced by IM2_RingElement_list_form().