def degrees_centered_at_zero(degrees):
    """Rescale degrees so they are centered at 0.

    Ouputs will range from -180 to 180.
    
    Parameters
    ----------
    degrees : :obj:`float`
        Degrees centered at 180 (e.g., ranging from 0 to 360)

    Returns
    -------
    :obj:`float`
        Degrees centered at 0
    """
    if degrees > 180:
        degrees = degrees - 360
    elif degrees < -180:
        degrees = degrees + 360
    elif degrees == -180:
        degrees = 180
    return degrees