On Mar 16, 3:51 pm, Shane Geiger <[EMAIL PROTECTED]> wrote: > lines = open('/tmp/foo.py', > "r").read().splitlines() > > previous_line = > '' > > for line in > lines: > > if "foo" in > line: > > print "found foo in the current line. The previous line is: " > + > previous_line > > previous_line = > line > > > > Qilong Ren wrote: > > Hi,all > > > I am new to this list. And I am glade I am here. > > I have a question. I need to do some text processing. I need to read > > from a file line by line. If some line is met with some condition, the > > previous line needs some modification. How to get the info of the > > previous line? > > > Thanks! > > Qilong > > > ------------------------------------------------------------------------ > > Never miss an email again! > > Yahoo! Toolbar > > <http://us.rd.yahoo.com/evt=49938/*http://tools.search.yahoo.com/toolb...> > > alerts you the instant new Mail arrives. Check it out. > > <http://us.rd.yahoo.com/evt=49937/*http://tools.search.yahoo.com/toolb...> > > -- > Shane Geiger > IT Director > National Council on Economic Education > [EMAIL PROTECTED] | 402-438-8958 | http://www.ncee.net > > Leading the Campaign for Economic and Financial Literacy > > sgeiger.vcf > 1KDownload
Hi, You should be able to use the file object's seek and tell methods. Or, since you're using a list, you could use a counter and when the text is found, you can print the previous line by subtracting one from the counter. counter = 0 for line in lines: if 'foo' == line: print 'found line. the previous line is: ' %s (lines[counter-1]) counter += 1 # Or something like that. Experiment! Mike -- http://mail.python.org/mailman/listinfo/python-list