coordutils.py 文件源码

def xmatch_basic(ra1, dec1, ra2, dec2, match_radius=5.0):
    '''
    This is a quick matcher that uses great_circle_dist to find the closest
    object in (ra2,dec2) within match_radius to (ra1,dec1). (ra1,dec1) must be a
    scalar pair, while (ra2,dec2) must be np.arrays of the same lengths.

    PARAMETERS:
    ra1/dec1: coordinates of the target to match
    ra2/dec2: coordinate np.arrays of the list of coordinates to match to

    RETURNS:

    A tuple like the following:

    (True -> no match or False -> matched,
     minimum distance between target and list)

    '''

    min_dist_arcsec = np.min(great_circle_dist(ra1,dec1,ra2,dec2))

    if (min_dist_arcsec < match_radius):
        return (True,min_dist_arcsec)
    else:
        return (False,min_dist_arcsec)