Function shift_p_mm_Mult

libpolys/polys/shiftop.cc:212–266

destroys p

// destroys p
poly shift_p_mm_Mult(poly p, const poly m, const ring ri)
{
#ifdef SHIFT_MULT_DEBUG
  PrintLn(); PrintS("shift_p_mm_Mult: "); p_wrp(m, ri, ri); PrintS(" * ("); p_wrp(p, ri, ri); PrintS(")");
#endif

  p_Test(p, ri);
  p_LmTest(m, ri);
  pAssume(m != NULL);
  assume(p!=NULL);

  int lV = ri->isLPring;
  poly _m = m; // temp hack because m is const
#ifdef SHIFT_MULT_COMPAT_MODE
  _m = p_Copy(_m, ri);
  p_mLPunshift(_m, ri);
  p_LPunshift(p, ri);
#else
  assume(p_mFirstVblock(_m, ri) <= 1);
  assume(p_FirstVblock(p, ri) <= 1); // TODO check that each block is <=1
#endif
  // at this point _m and p are shifted to 1

  poly q = p; // we use p for iterating and q for the result
  number mCoeff = pGetCoeff(_m);
  number pCoeff;
  pAssume(!n_IsZero(mCoeff, ri->cf));

  int *mExpV = (int *) omAlloc((ri->N+1)*sizeof(int));
  p_GetExpV(_m,mExpV,ri);
  int mLength = p_mLastVblock(_m, mExpV, ri) * lV;
  int *pExpV = (int *) omAlloc((ri->N+1)*sizeof(int));
  while (p != NULL)
  {
    pCoeff = pGetCoeff(p);
    pSetCoeff0(p, n_Mult(mCoeff, pCoeff, ri->cf));
    n_Delete(&pCoeff, ri->cf); // delete the old coeff

    p_GetExpV(p,pExpV,ri);
    p_LPExpVprepend(pExpV, mExpV, p_mLastVblock(p, pExpV, ri) * lV, mLength, ri);
    p_SetExpV(p, pExpV, ri);

    pIter(p);
  }
  omFreeSize((ADDRESS) pExpV, (ri->N+1)*sizeof(int));
  omFreeSize((ADDRESS) mExpV, (ri->N+1)*sizeof(int));
#ifdef SHIFT_MULT_COMPAT_MODE
  p_Delete(&_m, ri); // in this case we copied _m before
#endif
#ifdef SHIFT_MULT_DEBUG
  PrintLn(); PrintS("shift_p_mm_Mult result: "); p_wrp(q, ri, ri); PrintLn();
#endif
  p_Test(q, ri);
  return q;
}

// p - m*q destroys p
poly shift_p_Minus_mm_Mult_qq(poly p, poly m, poly q, int& Shorter, const poly /*spNoether*/, const ring ri) {