mult_by_term()

ring_elem SkewPolynomialRing::mult_by_term ( const ring_elem f, const ring_elem c, const int * m ) const

protectedvirtual

Reimplemented from PolyRing.

Definition at line 67 of file skewpoly.cpp.

{
  Nterm head;
  Nterm *inresult = &head;
 
  exponents_t EXP1 = ALLOCATE_EXPONENTS(exp_size);
  exponents_t EXP2 = ALLOCATE_EXPONENTS(exp_size);
  M_->to_expvector(m, EXP1);
 
  for (Nterm& s : f)
    {
      M_->to_expvector(s.monom, EXP2);
      int sign = skew_.mult_sign(EXP1, EXP2);
      if (sign == 0) continue;
 
      Nterm *t = new_term();
      t->next = nullptr;
      t->coeff = K_->mult(c, s.coeff);
      if (sign < 0) K_->negate_to(t->coeff);
 
      M_->mult(m, s.monom, t->monom);
      inresult->next = t;
      inresult = inresult->next;
    }
  inresult->next = nullptr;
  return head.next;
}

References ALLOCATE_EXPONENTS, Nterm::coeff, PolynomialRing::exp_size, PolynomialRing::K_, PolynomialRing::M_, Nterm::monom, PolyRing::new_term(), Nterm::next, s, and PolynomialRing::skew_.