lower_associate_divisor()

bool RingZZ::lower_associate_divisor ( ring_elem & f, ring_elem g ) const

virtual

Reimplemented from Ring.

Definition at line 206 of file ZZ.cpp.

{
  // This sets f to either 0, 1 or -1.
  // if f is 0, do f=sign(g), else f=sign(f)
  // return whether f is zero
  mpz_ptr result = RingZZ::new_elem();
  mpz_srcptr a = f.get_mpz();
  mpz_srcptr b = g.get_mpz();
  int sa = mpz_sgn(a);
  int sb = mpz_sgn(b);
  int s = (sa == 0 ? sb : sa);
 
  mpz_set_si(result, s);
  mpz_reallocate_limbs(result);  
 
  f = ring_elem(result);
  return !RingZZ::is_zero(f);
}

References ring_elem::get_mpz(), is_zero(), mpz_reallocate_limbs(), new_elem(), result(), and s.