def METHOD_NAME(self):
    y = np.array([1.0, 2])
    x = np.array([0.0, 0.0])
    theta_E = 1.0
    q = 0.9999
    s = 0.00001
    phi_G = 0
    e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
    values = self.nie.function(x, y, theta_E, e1, e2, s_scale=s)
    delta_pot = values[1] - values[0]
    values_spemd = self.sis.function(x, y, theta_E)
    delta_pot_spemd = values_spemd[1] - values_spemd[0]
    npt.assert_almost_equal(delta_pot, delta_pot_spemd, decimal=4)
    if bool_test is True:
        q = 0.99
        s = 0.000001
        phi_G = 0
        e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
        values = self.nie.function(x, y, theta_E, e1, e2, s_scale=s)
        delta_pot = values[1] - values[0]
        gamma = 2.0
        values_spemd = self.spemd.function(x, y, theta_E, gamma, e1, e2, s_scale=s)
        delta_pot_spemd = values_spemd[1] - values_spemd[0]
        npt.assert_almost_equal(delta_pot, delta_pot_spemd, decimal=2)