def METHOD_NAME(E):
    if E.abs().sum():  # check E != 0 for both floats and arrays
        try:
            m = _magn(E)
            assert (((1 <= m) & (m <= 5))).unique() == [True]
        except AssertionError:
            print(("Warning. Input values may not be in cm-1", E, "cm-1?"))