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天文数据与归档培训. 二进制星表. 何勃亮 国家天文台,中国虚拟天文台 hebl@nao.cas.cn. UCAC4 z100. col byte item fmt unit explanation notes - --------------------------------------------------------------------------
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天文数据与归档培训 二进制星表 何勃亮 国家天文台,中国虚拟天文台 hebl@nao.cas.cn
UCAC4 z100 col byte item fmt unit explanation notes --------------------------------------------------------------------------- 1 1- 3 ra I*4 mas right ascension at epoch J2000.0 (ICRS) (1) 2 5- 8 spd I*4 mas south pole distance epoch J2000.0 (ICRS) (1) 3 9-10 magm I*2 millimag UCAC fit model magnitude (2) 4 11-12 maga I*2 millimag UCAC aperture magnitude (2) 5 13 sigmag I*1 1/100 mag error of UCAC magnitude (3) 6 14 objt I*1 object type (4) 7 15 cdf I*1 combined double star flag (5)
Python 读取 # -*- coding: utf-8 -*- import struct def readU4(file): with open(file, 'rb') as f: chunk = f.read(78) while chunk != "": parseRc(chunk) chunk = f.read(78) """ 处理每条记录 rc为一个78字节长的二进制字段 """ defparseRc(rc): rcv = struct.unpack('2I2H1B', rc[0:13]) #只取部分字节 print "%d %d %d %d %d" % rcv readU4('z100')