def METHOD_NAME(self, x):
    try:
        E = self.parent().group()(x)
    except Exception:
        return None
    E = E.exponents()
    F = self.exponents()
    D = self.parent().gens_orders()
    r = sum( e*f/d for e,f,d in zip( E, F, D) )
    if isinstance(r, (int,Integer)):
        return 0
    n,d = r.numerator(), r.denominator()
    return n%d/d