power() [2/2]

ring_elem Z_mod::power ( const ring_elem f, mpz_srcptr n ) const

virtual

Exponentiation. This is the default function, if a class doesn't define this.

Reimplemented from Ring.

Definition at line 264 of file ZZp.cpp.

{
  if (f.get_int() == _ZERO) {
    if (mpz_sgn(n)<0) throw exc::division_by_zero_error();
    else if (mpz_sgn(n) == 0)
      return ring_elem(0);
    return ring_elem(_ZERO);
  }
  int n1 = RingZZ::mod_ui(n, _P1);
  int m = (f.get_int() * n1) % _P1;
  if (m < 0) m += _P1;
  return ring_elem(m);
}

References _P1, _ZERO, ring_elem::get_int(), and RingZZ::mod_ui().