def METHOD_NAME(self):
    x = np.array([1])
    y = np.array([2])
    phi_E = 1.0
    gamma = 1.9
    q = 1
    phi_G = 0.0
    e1, e2 = param_util.phi_q2_ellipticity(phi_G, q)
    E = phi_E / (((3 - gamma) / 2.0) ** (1.0 / (1 - gamma)) * np.sqrt(q))
    f_x_spep, f_y_spep = self.SPEP.derivatives(x, y, E, gamma, e1, e2)
    f_x_spp, f_y_spp = self.SPP.derivatives(x, y, E, gamma)
    npt.assert_almost_equal(f_x_spep, f_x_spp, decimal=9)
    npt.assert_almost_equal(f_y_spep, f_y_spp, decimal=9)
    x = np.array([0])
    y = np.array([0])
    f_x_spep, f_y_spep = self.SPEP.derivatives(x, y, E, gamma, e1, e2)
    f_x_spp, f_y_spp = self.SPP.derivatives(x, y, E, gamma)
    npt.assert_almost_equal(f_x_spep, f_x_spp, decimal=9)
    npt.assert_almost_equal(f_y_spep, f_y_spp, decimal=9)
    x = np.array([1, 3, 4])
    y = np.array([2, 1, 1])
    f_x_spep, f_y_spep = self.SPEP.derivatives(x, y, E, gamma, e1, e2)
    f_x_spp, f_y_spp = self.SPP.derivatives(x, y, E, gamma)
    npt.assert_almost_equal(f_x_spep, f_x_spp, decimal=9)
    npt.assert_almost_equal(f_y_spep, f_y_spp, decimal=9)