Looking for a Python Program/Tool That Will Add Line Numbers to a txt File

[Chris]

On Feb 14, 1:29 pm, John Machin <sjmac... at lexicon.net> wrote:
> On Feb 14, 6:13 pm, Chris <cwi... at gmail.com> wrote:
>
>
>
> > On Feb 14, 8:54 am, "W. Watson" <wolf_tra... at invalid.com> wrote:
>
> > > See Subject. It's a simple txt file, each line is a Python stmt, but I need
> > > up to four digits added to each line with a space between the number field
> > > and the text. Perhaps someone has already done this or there's a source on
> > > the web for it. I'm not yet into files with Python. A sudden need has burst
> > > upon me. I'm using Win XP.
> > > --
> > >                           Wayne Watson (Nevada City, CA)
>
> > >                         Web Page: <speckledwithStars.net>
>
> > enumerate through the file which will yield you a counter (starting @
> > zero so just add 1) and use the string function .zfill() to pad it out
> > for you.
> > eg.
>
> > for (line_cnt, each_line) in enumerate(input_file):
> >     output_file.write(print ('%s '%(line_cnt+1)).zfill(5) + each_line)
>
> (1) What's that "print" doing in there?
> (2) zfill(5)? The OP asked for "up to 4 digits", not 5.
> (2) As an alternative to str.zfill, consider using formatting:
>
> output_file.write('%04d %s' % (line_cnt+1, each_line))
>
> And what does "up to 4" mean? What does the OP want the 10000th line
> to look like?

print was a typo
take a look at the string that is built before the zfill fires, it has
a trailing space so it is correct. ;)