do a sed / awk filter with python tools (at least as fast)

[Mathieu Prevot]

Hi,

I use in a bourne shell script the following filter:

sed '/watch?v=/! d;s/.*v=//;s/\(.\{11\}\).*/\1/' \
| sort | uniq | awk 'ORS=" "{print $1}'

that give me all sets of 11 characters that follows the "watch?v="
motif. I would like to do it in python on stdout from a
subprocess.Pope n instance, using python tools rather than sed awk etc.
How can I do this ? Can I expect something as fast ?

Thanks,
Mathieu

[Peter Otten]

Re: do a sed / awk filter with python tools (at least as fast)

Mathieu Prevot wrote:

I use in a bourne shell script the following filter:
>
sed '/watch?v=/! d;s/.*v=//;s/\(.\{11\}\).*/\1/' \
| sort | uniq | awk 'ORS=" "{print $1}'
>
that give me all sets of 11 characters that follows the "watch?v="
motif. I would like to do it in python on stdout from a
subprocess.Pope n instance, using python tools rather than sed awk etc.
How can I do this ? Can I expect something as fast ?

You should either do it in Python , e. g.:

def process(lines):
candidates = (line.rstrip(). partition("/watch?v=") for line in lines)
matches = (c[:11] for a, b, c in candidates if len(c) >= 11)
print " ".join(sorted(s et(matches)))

if __name__ == "__main__":
import sys
process(sys.std in)

or invoke your shell script via subprocess.Pope n(). Invoking a python script
via subprocess doesn't make sense IMHO.

Peter

[Mathieu Prevot]

Re: do a sed / awk filter with python tools (at least as fast)

2008/7/7 Peter Otten <__peter__@web. de>:

Mathieu Prevot wrote:
>

>I use in a bourne shell script the following filter:
>>
>sed '/watch?v=/! d;s/.*v=//;s/\(.\{11\}\).*/\1/' \
>| sort | uniq | awk 'ORS=" "{print $1}'
>>
>that give me all sets of 11 characters that follows the "watch?v="
>motif. I would like to do it in python on stdout from a
>subprocess.Pop en instance, using python tools rather than sed awk etc.
>How can I do this ? Can I expect something as fast ?

>
You should either do it in Python , e. g.:
>
def process(lines):
candidates = (line.rstrip(). partition("/watch?v=") for line in lines)
matches = (c[:11] for a, b, c in candidates if len(c) >= 11)
print " ".join(sorted(s et(matches)))
>
if __name__ == "__main__":
import sys
process(sys.std in)
>
or invoke your shell script via subprocess.Pope n(). Invoking a python script
via subprocess doesn't make sense IMHO.

:) Thanks.
Mathieu