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Groups > comp.lang.c > #126783
| From | David Brown <david.brown@hesbynett.no> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Text Files |
| Date | 2018-02-16 13:10 +0100 |
| Organization | A noiseless patient Spider |
| Message-ID | <p66ho1$c2r$1@dont-email.me> (permalink) |
| References | (2 earlier) <p64vnk$gm3$1@dont-email.me> <87mv097tcf.fsf@bsb.me.uk> <dsphC.15908$zy1.12073@fx30.am4> <p668md$gp3$1@dont-email.me> <87lgft4145.fsf@bsb.me.uk> |
On 16/02/18 12:36, Ben Bacarisse wrote:
> David Brown <david.brown@hesbynett.no> writes:
>
>> On 16/02/18 01:19, bartc wrote:
>>> On 15/02/2018 22:58, Ben Bacarisse wrote:
>>>> jacobnavia <jacob@jacob.remcomp.fr> writes:
>>>
>>>>> That last one is difficult to beat.
>>>>
>>>> Yes, I know what C's good at, but I was asking the OP. It's possible
>>>> that none of that matters to them. It could be a quick throwaway
>>>> program to find the line with the widest range:
>>>>
>>>> awk 'NF==6 { if ($6-$1 > r) { r = $6-$1; ln = NR }} END { print ln }'
>>>>
>>>> I'm shameless enough to say that I'm a pretty fast C programmer but,
>>>> none the less, I'd write that sort of thing in AWK every time.
>>>>
>>>>> C is fast. Fast because it is just an abstraction of the machine.
>>>>
>>>> I changed my C version to do this calculation and found that the AWK
>>>> version was faster.
>>>
>>> So, the task is to find the line where column 6 is bigger than column 1
>>> by the maximum amount?
>>>
>>> I tried your code in gawk, on a 1-million line input file containing 6
>>> columns of random numbers from 1 to 100,000.
>>>
>>> Gawk took 1.64 seconds.
>>>
>>> Then I threw something together with my scripting language, and it took
>>> 1.50 seconds at the first attempt [code shown in my sig].
>>
>> Since we are having fun, I tested a simple python implementation.
>>
>> awk took 0.44s.
>> Python2 and Python3 both took 0.9 seconds.
>> pypy (JIT compiled python) took 0.37 seconds.
>>
>> All this shows that for a task like this, many languages are within
>> spitting distance of the speed of C,
>
> I don't see how you can say that without a C data point on the same
> machine. And, being very flexible, C code comes in with very different
> timings depending on the exact job being done (for the "max range"
> problem I got a fact of 10 between two simple C programs).
"Within spitting distance" does not mean the same speed. It means fast
enough to be usable for the same sort of task. I haven't bothered to
write C code for the job or test posted C code on the same system - it
is good enough for me to use the figures others have posted with speeds
faster than awk, but not massively faster. There is no clearly
specified problem here, so we are making guesses and approximations. If
we can rely on all numbers in the file being two digit and having 4
spaces between them, you can make a much faster C program for the job.
But if the layout varies and integer sizes exceed 64 bits, you'll have a
hard job significantly beating pypy with C (noting that most of the work
done during the python execution is from very optimised C code).
What we have shown in these few posts is that when you want to analyse
lines of a text file with integer data, a language like Python (or awk,
if the problem is simple enough, or even Bart's scripting language if he
is the one solving the problem) is likely to give you a solid fraction
of the speed of C with vastly less development effort.
>
>> while being vastly simpler, clearer
>> and easier to write. (With the details there depending on the
>> programmer and the task in question.)
>
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Text Files G B <gb@gb.com> - 2018-02-14 11:47 -0400
Re: Text Files Ed Prochak <edprochak@gmail.com> - 2018-02-14 08:45 -0800
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-14 08:47 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-15 01:17 -0800
Re: Text Files gordonb.ea2mq@burditt.org (Gordon Burditt) - 2018-02-14 11:10 -0600
Re: Text Files "James R. Kuyper" <jameskuyper@verizon.net> - 2018-02-14 12:28 -0500
Re: Text Files jt@toerring.de (Jens Thoms Toerring) - 2018-02-14 21:07 +0000
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-14 15:31 -0700
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-15 06:59 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 10:20 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-14 22:51 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-15 11:04 +0100
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-15 06:16 -0800
Re: Text Files "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-15 22:22 +0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-15 15:58 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 16:31 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-15 21:31 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 21:21 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 22:17 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 23:36 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 23:48 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 10:09 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 12:57 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 15:50 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 15:50 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 17:07 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 20:44 +0000
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-17 11:22 +1300
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 17:48 +0000
Re: Text Files GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-16 17:06 +0100
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-17 11:10 +1300
Re: Text Files supercat@casperkitty.com - 2018-02-16 14:48 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-16 15:14 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 23:25 +0000
Re: Text Files supercat@casperkitty.com - 2018-02-16 15:50 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-16 07:19 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 17:13 +0100
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-19 17:55 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-19 19:14 +0100
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-19 11:48 -0800
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 08:14 -0800
Re: Text Files Robert Wessel <robertwessel2@yahoo.com> - 2018-02-17 18:32 -0600
Re: Text Files jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-15 22:57 +0100
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 22:58 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 00:19 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 02:26 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 02:57 +0000
Re: Text Files asetofsymbols@gmail.com - 2018-02-16 00:21 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 11:30 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 10:36 +0100
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 11:36 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 13:10 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 12:25 +0000
Re: Text Files Ike Naar <ike@iceland.freeshell.org> - 2018-03-06 19:33 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-03-06 20:55 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 04:42 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 16:58 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 20:02 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 21:43 +0100
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-17 04:01 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-17 13:10 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-17 05:27 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-17 14:20 +0000
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-16 09:04 -0700
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 14:31 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 06:42 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 14:58 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 07:23 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 15:24 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 04:13 -0800
Re: Text Files Siri Cruise <chine.bleu@yahoo.com> - 2018-02-16 04:29 -0800
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-20 16:41 +0000
Re: Text Files Siri Cruise <chine.bleu@yahoo.com> - 2018-02-20 09:39 -0800
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-20 19:16 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 12:46 +0000
Re: Text Files GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-15 14:52 +0100
Re: Text Files Anton Shepelev <anton.txt@g{oogle}mail.com> - 2018-02-15 17:07 +0300
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 14:23 +0000
Re: Text Files Anton Shepelev <anton.txt@g{oogle}mail.com> - 2018-02-15 18:52 +0300
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 14:39 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 15:43 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 20:32 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 22:06 +0000
Re: Text Files GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-15 23:12 +0100
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-15 15:12 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 23:43 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 23:54 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 23:35 +0000
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-16 17:07 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-17 02:38 +0000
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-17 17:26 +1300
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-17 11:22 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-17 12:07 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-17 04:17 -0800
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-17 16:25 +0300
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-17 07:35 -0800
Re: Text Files GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-17 15:24 +0100
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-18 11:10 +1300
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-19 12:05 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-19 15:32 -0800
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-21 10:34 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-21 15:35 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-22 00:11 +0000
Re: Text Files Robert Wessel <robertwessel2@yahoo.com> - 2018-02-21 18:26 -0600
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-21 21:39 -0800
Re: Text Files Robert Wessel <robertwessel2@yahoo.com> - 2018-02-23 03:08 -0600
Re: Text Files supercat@casperkitty.com - 2018-02-23 16:16 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-23 16:46 -0800
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-24 02:49 -0800
Re: Text Files asetofsymbols@gmail.com - 2018-02-24 05:16 -0800
Re: Text Files "F. Russell" <fr@random.info> - 2018-02-24 14:35 +0000
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-24 08:48 -0700
Re: Text Files supercat@casperkitty.com - 2018-02-25 15:09 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-25 15:54 -0800
Re: Text Files supercat@casperkitty.com - 2018-02-26 11:04 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-26 11:52 -0800
Re: Text Files supercat@casperkitty.com - 2018-02-26 14:12 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-26 14:40 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-22 04:58 -0800
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-22 05:33 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-22 13:59 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-22 07:24 -0800
Re: Text Files supercat@casperkitty.com - 2018-02-20 12:14 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-15 21:37 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 21:34 +0000
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-15 14:15 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 10:47 +0100
Re: Text Files "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-15 22:20 +0800
Re: Text Files "F. Russell" <fr@random.info> - 2018-02-15 15:24 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 16:05 +0000
Re: Text Files "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-16 00:22 +0800
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-15 13:35 -0700
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-25 00:13 +0300
Re: Text Files bartc <bc@freeuk.com> - 2018-02-24 21:24 +0000
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-25 14:55 +0300
Re: Text Files bartc <bc@freeuk.com> - 2018-02-25 13:00 +0000
Re: Text Files Real Troll <Real.Troll@Trolls.com> - 2018-02-24 17:35 -0400
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-24 21:36 +0000
Re: Text Files Real Troll <Real.Troll@Trolls.com> - 2018-02-24 17:45 -0400
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-24 22:51 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-24 23:56 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-25 00:14 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-25 00:22 +0000
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-25 15:16 +0300
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-25 15:20 -0800
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-25 20:27 -0700
Re: Text Files gazelle@shell.xmission.com (Kenny McCormack) - 2018-02-26 06:19 +0000
Re: Text Files Anton Shepelev <anton.txt@g{oogle}mail.com> - 2018-02-26 15:35 +0300
Re: Text Files Reinhardt Behm <rbehm@hushmail.com> - 2018-02-26 20:53 +0800
Grammar Patrol (Was: Text Files) gazelle@shell.xmission.com (Kenny McCormack) - 2018-02-26 17:54 +0000
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-26 15:27 +0000
Re: Text Files Anton Shepelev <anton.txt@g{oogle}mail.com> - 2018-02-26 18:50 +0300
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-26 09:26 -0800
Re: Text Files scott@slp53.sl.home (Scott Lurndal) - 2018-02-26 19:46 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-27 09:04 +0100
Re: Text Files already5chosen@yahoo.com - 2018-02-27 00:56 -0800
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-27 22:07 +1300
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-27 14:37 +0100
Re: Text Files already5chosen@yahoo.com - 2018-02-27 07:38 -0800
Re: Text Files supercat@casperkitty.com - 2018-02-27 09:18 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-27 10:15 +0100
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-27 08:53 -0800
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-26 23:14 -0800
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-26 08:32 -0700
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-26 09:17 -0800
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-26 22:55 -0800
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-25 15:02 +0300
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-25 20:12 +0000
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