def METHOD_NAME(res):
    """Tests evaluating keff."""
    t, k = res.get_keff()
    t_min, k = res.get_keff(time_units='min')
    t_ref = [0.0, 1296000.0, 2592000.0, 3888000.0]
    k_ref = [1.1596402556, 1.1914183335, 1.2292570871, 1.1797030302]
    u_ref = [0.0270680649, 0.0219163444, 0.024268508 , 0.0221401194]
    np.testing.assert_allclose(t, t_ref)
    np.testing.assert_allclose(t_min * 60, t_ref)
    np.testing.assert_allclose(k[:, 0], k_ref)
    np.testing.assert_allclose(k[:, 1], u_ref)