def test_vector_gamma_z0_media(self):
        """
        test ability to create a Media from vector quantities for gamma/z0
        """
        freq = Frequency(1,10,101)
        a = DefinedGammaZ0(freq,
                           gamma = 1j*npy.ones(len(freq)) ,
                           z0 =  50*npy.ones(len(freq)),
                            )


        self.assertEqual(a.line(1),a.line(1))
        with self.assertRaises(NotImplementedError):
            a.npoints=4