def convert_ddmmss_to_float(astring):
    """Convert sexigesimal to decimal degrees

    Parameters
    ----------
    astring: str
        The sexigesimal coordinate.

    Returns
    -------
    hour_or_deg : float
        The converted coordinate.
    """
    aline = astring.split(':')
    d = float(aline[0])
    m = float(aline[1])
    s = float(aline[2])
    hour_or_deg = (s/60.+m)/60.+d
    return hour_or_deg