def overlap(a, b):
    """
    True if two Fields overlap, otherwise False

    Parameters
    ----------
    a, b : `~lentil.Field`
        Input fields.

    Returns
    -------
    overlap : bool
    """
    armin, armax, acmin, acmax = a.extent
    brmin, brmax, bcmin, bcmax = b.extent
    return armin <= brmax and armax >= brmin and acmin <= bcmax and acmax >= bcmin