read a files particular line

[Frank Grellert]

Hi,
does anybody have an idea how to read a particular line of a file like awk's
awk '{if( NR==12) print $0}' filename (reads lineno 12 of filename)

thanks for your help

Frank Grellert

[Kristóf Stróbl]

Re: read a files particular line

Hi,

If the file is not too big use:

file("filename" ).readlines()[11]

Kristóf

Frank Grellert wrote:
[color=blue]
> Hi,
> does anybody have an idea how to read a particular line of a file like awk's
> awk '{if( NR==12) print $0}' filename (reads lineno 12 of filename)
>
> thanks for your help
>
> Frank Grellert[/color]

[Peter L Hansen]

Re: read a files particular line

Kristóf Stróbl wrote (top-posting, but I fixed it. You're welcome.):[color=blue]
> Frank Grellert wrote:[color=green]
>> does anybody have an idea how to read a particular line of a file
>> like awk's awk '{if( NR==12) print $0}' filename (reads lineno 12 of
>> filename)[/color]
>
> If the file is not too big use:
>
> file("filename" ).readlines()[11][/color]

And if the file is "too big", there's always iterators:

print itertools.islic e(open('tempx.t xt'), 11, 12).next()

A little more complicated, but avoids reading the entire file
into memory.

-Peter

[Miki Tebeka]

Re: read a files particular line

Hello Frank,
[color=blue]
> Hi,
> does anybody have an idea how to read a particular line of a file like awk's
> awk '{if( NR==12) print $0}' filename (reads lineno 12 of filename)[/color]
Check the documentation about the "linecache" .

HTH.
--
------------------------------------------------------------------------
Miki Tebeka <miki.tebeka@gm ail.com>

http://tebeka.spymac.net

The only difference between children and adults is the price of the toys

[Michael Hudson]

Re: read a files particular line

Frank Grellert <fgrellert@t-online.de> writes:
[color=blue]
> Hi,
> does anybody have an idea how to read a particular line of a file like awk's
> awk '{if( NR==12) print $0}' filename (reads lineno 12 of filename)
>[/color]

for lineno, line in enumerate(open_ file):
# lineno starts at 0, though

Cheers,
mwh

--
<radix> I feel so special when people quote me
-- from Twisted.Quotes

[Alex Martelli]

Re: read a files particular line

Frank Grellert <fgrellert@t-online.de> wrote:
[color=blue]
> does anybody have an idea how to read a particular line of a file like awk's
> awk '{if( NR==12) print $0}' filename (reads lineno 12 of filename)[/color]

Standard Python library module linecache, which others suggested, is
your best bet. itertools.islic e(open('filenam e'), 12, 13).next() should
also work (after an 'import itertools' of course, since it, too, is a
module in the standard library) and might be faster if you'll never need
to get any other line from that file in the course of your program.


Alex