On Thu, Feb 26, 2009 at 4:32 PM, Brett Hedges <lilhedge...@yahoo.com> wrote: > > Hi, > > I am using both xreadlines and files iterators for a script that I need to > finish. I am iterating over the entire file but stopping to use xreadlines to > grab certain lines as strings to process them. > > My question is how do I go to a previous line in the file? xreadlines has a > file.next() statement that gives the next line, and I need a statement that > gives me the previous line. > > My script has a loop that looks for a certain word then breaks the loop. But > I need to go to the previous line before I break since the script uses that > line (which gets processed). I'm sure there is an easier way to do this but > since I am new to python and have spent a lot of time on this script I can't > really go back and change a lot of things unless there is no possible way. > Something like the example below. > > f.open("text.txt",'r') > files = f.xreadlines() > Name = "Section 1" > > prev_line = None > for line in f: > if Name in line: > while x<20 > field = files.next() > if "2.6" in field: use(prev_line) > *****files.previousline()***** > break prev_line = line > x=x+1
Also, you could probably make the loop prettier by using enumerate() or range() to track `x`. Cheers, Chris -- Follow the path of the Iguana... http://rebertia.com -- http://mail.python.org/mailman/listinfo/python-list