def _evaluate_ground(f, i, a):
 ring = f.ring.clone(domain=f.ring.domain.ring.drop(i))
 fa = ring.zero
 for (monom, coeff) in f.iterterms():
  fa[monom] = coeff.evaluate(i, a)
 return fa

def _evaluate_ground ( f , i , a ) : ring = f . ring . clone ( domain = f . ring . domain . ring . drop ( i ) ) fa = ring . zero for ( monom , coeff ) in f . iterterms ( ) : fa [ monom ] = coeff . evaluate ( i , a ) return fa
evaluate a polynomial f at a in the i-th variable of the ground domain .