def allclose(a, b, align=False, rtol=1.e-5, atol=1.e-8):
    """Compare two molecules for numerical equality.

    Args:
        a (Cartesian):
        b (Cartesian):
        align (bool): a and b are
            prealigned along their principal axes of inertia and moved to their
            barycenters before comparing.
        rtol (float): Relative tolerance for the numerical equality comparison
            look into :func:`numpy.allclose` for further explanation.
        atol (float): Relative tolerance for the numerical equality comparison
            look into :func:`numpy.allclose` for further explanation.

    Returns:
        bool:
    """
    return np.alltrue(isclose(a, b, align=align, rtol=rtol, atol=atol))