ARingGFFlintBig()

M2::ARingGFFlintBig::ARingGFFlintBig	(	const PolynomialRing &	R,
		const ring_elem	a )

Definition at line 10 of file aring-gf-flint-big.cpp.

    : mOriginalRing(R),
      mCharacteristic(R.characteristic()),
      mGeneratorComputed(false)
{
 
  // TODO: assert that the base ring of R is ZZ/p.
  // TODO: if mDimension <= 1 then give an error.
  ring_elem b = R.copy(a);
  mPrimitiveElement = RingElement::make_raw(&R, b);
  ring_elem minpoly = mOriginalRing.quotient_element(0);
 
  std::vector<long> poly;
  RingElement F(&R, minpoly);
  F.getSmallIntegerCoefficients(poly);
 
  // warning: flint expects unsigned longs, so we must make
  // all of these coeffs non-negative.
  for (long i = poly.size() - 1; i >= 0; i--)
    {
      long a = poly[i];
      if (a == 0) continue;
      if (a < 0) poly[i] += characteristic();
    }
 
  mDimension = poly.size() - 1;
 
#if 0
    printf("minpoly: ");
    for (long i=0; i<poly.size(); i++)
      printf(" %ld", poly[i]);
    printf("\n");
#endif
  nmod_poly_t mMinPoly;
  nmod_poly_init(mMinPoly, R.characteristic());
 
  for (long i = poly.size() - 1; i >= 0; i--)
    if (poly[i] != 0) nmod_poly_set_coeff_ui(mMinPoly, i, poly[i]);
 
  fq_nmod_ctx_init_modulus(mContext, mMinPoly, "a");
#if 0
    fq_nmod_ctx_print(mContext);
#endif
  nmod_poly_clear(mMinPoly);
 
  // powers of p, as ulongs's
  mPPowers = newarray_atomic(unsigned int, mDimension + 1);
  mPPowers[0] = 1;
  for (long i = 1; i <= mDimension; i++)
    mPPowers[i] = mPPowers[i - 1] * static_cast<unsigned int>(mCharacteristic);
 
  FLINT_RAND_INIT(mRandomState);
}

References characteristic(), Ring::characteristic(), Ring::copy(), FLINT_RAND_INIT, RingElement::getSmallIntegerCoefficients(), RingElement::make_raw(), mCharacteristic, mContext, mDimension, mGeneratorComputed, mOriginalRing, mPPowers, mPrimitiveElement, mRandomState, and newarray_atomic.

Referenced by M2::ARingGFFlintBig::Element::Element(), M2::ARingGFFlintBig::Element::Element(), and M2::ARingGFFlintBig::ElementArray::ElementArray().