Reading/Editing large text files

[mickey17]

I am a newbie! yay! i would love it if someone can show me how to copy part of a text file to a new text file. *for instance assuming that the part of the file i want to copy goes from 'tommy' to 'jenny'

 

[StoneDeCroze]

dunno if this makes sense, but it prints all the lines from the flat file 'CLIENTS.CSV' where the first letter is L

I am sure there are easy ways - but it's all I could think of on the spur of the moment.

I tried it on a 24mb client file and it only took a second to work out (took ages to display it to screen)

Peter


file = file('d:\\CLIENTS.CSV').readlines()
startline, endline, counter = 0, 0, 0
for line in file:
counter = counter +1
if line.startswith('L') and startline==0:
startline = counter
endline = counter
if line.startswith('M') and startline==endline:
endline = counter

print file[startline:endline]