Path: csiph.com!usenet.pasdenom.info!weretis.net!feeder4.news.weretis.net!ecngs!feeder2.ecngs.de!newsfeed.freenet.ag!news2.euro.net!newsfeed.xs4all.nl!newsfeed3.news.xs4all.nl!xs4all!post.news.xs4all.nl!not-for-mail Return-Path: X-Original-To: python-list@python.org Delivered-To: python-list@mail.python.org X-Spam-Status: OK 0.003 X-Spam-Evidence: '*H*': 0.99; '*S*': 0.00; 'output': 0.04; 'patterns': 0.04; 'attribute': 0.05; 'pat': 0.05; '-*-': 0.07; 'utf-8': 0.07; 'python': 0.09; 'coding:': 0.09; 'from:addr:mrabarnett.plus.com': 0.16; 'from:addr:python': 0.16; 'from:name:mrab': 0.16; 'literals': 0.16; 'message-id:@mrabarnett.plus.com': 0.16; 'output?': 0.16; 'received:84.93': 0.16; 'received:84.93.230': 0.16; 'subject:expression': 0.16; 'subject:regular': 0.16; 'string': 0.17; 'wrote:': 0.17; 'skip:p 30': 0.20; 'import': 0.21; 'example': 0.23; 'this:': 0.23; 'header:In-Reply-To:1': 0.25; 'header:User-Agent:1': 0.26; 'skip:" 20': 0.26; '(most': 0.27; 'raw': 0.27; "doesn't": 0.28; 'optional': 0.29; 'skip:( 40': 0.30; 'subject: ?': 0.30; 'code': 0.31; 'file': 0.32; 'received:84': 0.32; 'print': 0.32; 'traceback': 0.33; 'problem': 0.33; 'to:addr :python-list': 0.33; 'code:': 0.33; 'recommended': 0.33; 'but': 0.36; 'subject:: ': 0.38; 'skip:( 30': 0.38; 'object': 0.38; 'to:addr:python.org': 0.39; 'received:192': 0.39; 'skip:" 10': 0.40; 'received:192.168': 0.40; 'url:ip addr': 0.62; 'skip:n 10': 0.63; 'here': 0.65; 'header:Reply-To:1': 0.68; '8bit%:100': 0.70; '8bit%:92': 0.70; 'reply-to:no real name:2**0': 0.72; '8bit%:45': 0.84; '8bit%:65': 0.84; '8bit%:66': 0.84; 'reply- to:addr:python.org': 0.84; 'url:177': 0.84; 'url:202': 0.84 X-CM-Score: 0.00 X-CNFS-Analysis: v=2.0 cv=HO4d4PRv c=1 sm=1 a=0nF1XD0wxitMEM03M9B4ZQ==:17 a=Tv4_tr9OjFAA:10 a=l2ldf9mSM50A:10 a=ihvODaAuJD4A:10 a=OUOv7kDek9cA:10 a=IkcTkHD0fZMA:10 a=EBOSESyhAAAA:8 a=8AHkEIZyAAAA:8 a=yrlwa_sxtEwA:10 a=_CEnuSUOAAAA:8 a=u1Y1aK5dOgtMhRN7vxUA:9 a=QEXdDO2ut3YA:10 a=sSxwxQke6HgA:10 a=Zhm7LKGWaE8A:10 a=J_3VfmUUkkMA:10 a=mixiRZqWv8AA:10 a=0mPxtDiXJLIA:10 a=qiWi7Edwir4A:10 a=NWVoK91CQyQA:10 a=0nF1XD0wxitMEM03M9B4ZQ==:117 X-AUTH: mrabarnett:2500 Date: Thu, 14 Feb 2013 15:43:42 +0000 From: MRAB User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/20130107 Thunderbird/17.0.2 MIME-Version: 1.0 To: python-list@python.org Subject: Re: how to right the regular expression ? References: <227f6014.405c.13cd90da3d4.Coremail.mailtomanage@163.com> In-Reply-To: <227f6014.405c.13cd90da3d4.Coremail.mailtomanage@163.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-BeenThere: python-list@python.org X-Mailman-Version: 2.1.15 Precedence: list Reply-To: python-list@python.org List-Id: General discussion list for the Python programming language List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Newsgroups: comp.lang.python Message-ID: Lines: 62 NNTP-Posting-Host: 2001:888:2000:d::a6 X-Trace: 1360856630 news.xs4all.nl 6935 [2001:888:2000:d::a6]:36587 X-Complaints-To: abuse@xs4all.nl Xref: csiph.com comp.lang.python:38866 On 2013-02-14 14:13, python wrote: > my tv.txt is : > http://202.177.192.119/radio5 香港电台第五台(可于Totem/VLC/MPlayer播放) > http://202.177.192.119/radio35 香港电台第五台(DAB版，可于Totem/VLC/MPlayer播放) > http://202.177.192.119/radiopth 香港电台普通话台(可于Totem/VLC/MPlayer播放) > http://202.177.192.119/radio31 香港电台普通话台(DAB版，可于Totem/VLC/MPlayer播放) > octoshape:rthk.ch1 香港电台第一台(粤) > octoshape:rthk.ch2 香港电台第二台(粤) > octoshape:rthk.ch6 香港电台普通话台 > octoshape:rthk.ch3 香港电台第三台(英) > > what i want to get the result is > 1group is http://202.177.192.119/radio5 2group is 香港电台第五台 3group is (可于Totem/VLC/MPlayer播放) > 1group is http://202.177.192.119/radio35 2group is 香港电台第五台 3group is (DAB版，可于Totem/VLC/MPlayer播放) > 1group is http://202.177.192.119/radiopth 2group is 香港电台普通话台 3group is (可于Totem/VLC/MPlayer播放) > 1group is http://202.177.192.119/radio31 2group is 香港电台普通话台 3group is (DAB版，可于Totem/VLC/MPlayer播放) > 1group is octoshape:rthk.ch1 2group is 香港电台第一台 3group is (粤) > 1group is octoshape:rthk.ch2 2group is 香港电台第二台 3group is (粤) > 1group is octoshape:rthk.ch6 2group is 香港电台普通话台 3group is none > 1group is octoshape:rthk.ch3 2group is 香港电台第三台 3group is (英) > > here is my code: > # -*- coding: utf-8 -*- > import re > rfile=open("tv.txt","r") > pat='([a-z].+?\s)(.+)(\(.+\))' > for line in rfile.readlines(): > Match=re.match(pat,line) > print "1group is ",Match.group(1),"2group is > ",Match.group(2),"3group is ",Match.group(3) > rfile.close() > > the output is : > 1group is http://202.177.192.119/radio5 2group is 香港电台第五台 > 3group is (可于Totem/VLC/MPlayer播放) > 1group is http://202.177.192.119/radio35 2group is 香港电台第五台 > 3group is (DAB版，可于Totem/VLC/MPlayer播放) > 1group is http://202.177.192.119/radiopth 2group is 香港电台普通话台 > 3group is (可于Totem/VLC/MPlayer播放) > 1group is http://202.177.192.119/radio31 2group is 香港电台普通话台 > 3group is (DAB版，可于Totem/VLC/MPlayer播放) > 1group is octoshape:rthk.ch1 2group is 香港电台第一台 3group is (粤) > 1group is octoshape:rthk.ch2 2group is 香港电台第二台 3group is (粤) > 1group is > Traceback (most recent call last): > File "tv.py", line 7, in > print "1group is ",Match.group(1),"2group is ",Match.group(2),"3group is ",Match.group(3) > AttributeError: 'NoneType' object has no attribute 'group' > > how to revise my code to get the output? > The problem is that the regex makes '(\(.+\))' mandatory, but example 7 doesn't match it. You can make it optional by wrapping it in a non-capturing group (?:...), like this: pat = r'([a-z].+?\s)(.+)(?:(\(.+\)))?' Also, it's highly recommended that you use raw string literals (r'...') when writing regex patterns and replacements.