|  | do a sed / awk filter with python tools (at least as fast) | | |
| | | Mathieu Prevot |  |
|  Posted: Mon Jul 07, 2008 3:32 pm Post subject: do a sed / awk filter with python tools (at least as fast) |  |
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.Popen instance, using python tools rather than sed awk etc.
How can I do this ? Can I expect something as fast ?
Thanks,
Mathieu |
| |
| | | Peter Otten | |
| | Posted: Mon Jul 07, 2008 6:04 pm Post subject: Re: do a sed / awk filter with python tools (at least as fas | |
Mathieu Prevot wrote:
| Quote: | 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.Popen 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(set(matches)))
if __name__ == "__main__":
import sys
process(sys.stdin)
or invoke your shell script via subprocess.Popen(). Invoking a python script
via subprocess doesn't make sense IMHO.
Peter |
| |
| | | Mathieu Prevot | |
| | Posted: Mon Jul 07, 2008 6:53 pm Post subject: Re: do a sed / awk filter with python tools (at least as fas | |
2008/7/7 Peter Otten <__peter__@web.de>:
| Quote: | 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.Popen 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(set(matches)))
if __name__ == "__main__":
import sys
process(sys.stdin)
or invoke your shell script via subprocess.Popen(). Invoking a python script
via subprocess doesn't make sense IMHO.
|
 Thanks.
Mathieu |
| |
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