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Groups > comp.lang.c > #126774

Re: Text Files

From Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups comp.lang.c
Subject Re: Text Files
Date 2018-02-16 02:57 +0000
Organization A noiseless patient Spider
Message-ID <87bmgp63qn.fsf@bsb.me.uk> (permalink)
References (1 earlier) <87mv0b9ocq.fsf@bsb.me.uk> <p64vnk$gm3$1@dont-email.me> <87mv097tcf.fsf@bsb.me.uk> <dsphC.15908$zy1.12073@fx30.am4> <bjrhC.128711$b66.2682@fx42.am4>

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bartc <bc@freeuk.com> writes:

> On 16/02/2018 00:19, 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.
>
>> Then, since you said that C was slower, I tweaked my demo program of this morning, and it did the test in 0.67 seconds.
>
> Best timing I could get out of C was 0.22 seconds (compiled with gcc-O3), using a modified parser that reads the whole file into memory.
>
> With full error-checking, about 0.25, but I don't have time to make it efficient. About 4M lines per second, not unreasonable.
>
> What sort of timings between AWK and C were you getting?

With a 2,000,000 line file, AWK takes about 1.2 seconds.  C using sscanf
to parse all six numbers: 2 seconds.  A C program that uses strtol on
the first and last part of the line: 0.2 seconds.  Both C programs read
line by line and are compiled -O3.

-- 
Ben.

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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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