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Re: How to extract *and reorder* columns?
From: |
kj |
Subject: |
Re: How to extract *and reorder* columns? |
Date: |
Sun, 2 Mar 2008 17:16:40 +0000 (UTC) |
User-agent: |
nn/6.7.3 |
In <mailman.8151.1204415571.18990.help-gnu-utils@gnu.org> bob@proulx.com (Bob
Proulx) writes:
>kj wrote:
>> I need to extract and reorder some columns from some very large
>> files. GNU cut will extract the columns nicely and quickly, but
>> won't reorder them. I can do the reordering easily by piping the
>> output of cut through a perl one-liner, but I'm looking for something
>> faster.
>>
>> Is there a GNU utility that will do this?
>Not just GNU but POSIX standard. Use awk.
This is quite a revelation. I never knew that awk was so much
faster than perl. I'm getting speed-ups of 6 or 7-fold...
Thanks!
kynn
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