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Re: Catching overflow

From Ben Bacarisse <ben.usenet@bsb.me.uk>
Newsgroups comp.lang.c
Subject Re: Catching overflow
Date 2018-02-26 18:31 +0000
Organization A noiseless patient Spider
Message-ID <87a7vvsiv7.fsf@bsb.me.uk> (permalink)
References (2 earlier) <p6vl8r$2c3$1@dont-email.me> <878tbgtudk.fsf@bsb.me.uk> <p70lfc$ia3$1@dont-email.me> <87r2p7sro9.fsf@bsb.me.uk> <p71gqr$o1v$2@dont-email.me>

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jacobnavia <jacob@jacob.remcomp.fr> writes:

> Le 26/02/2018 à 16:21, Ben Bacarisse a écrit :
>> I'm not sure what that format is, but even if it has 480 mantissa bits
>> you can only go up to catalan(246)
>
> No, because itr is a 480 bits FLOATING POINT format, so I have a
> maximum exponent of pow(10,1048576) !!!
>
> * catalan(2000)
> 8.31033420806514277630952936761809874071077260064288028 \
> 5497172797668390892100214567591803395202640482817294746 \
> 21481841400922937726151E+1198
>
> Of course I get "only" the first 135 digits...

There abouts.  You seem to have about 131 or 132 digits.

I was assuming you were calculating the Catalan numbers using floating
point.  In fact you are using floating point to approximate Catalan
numbers.  That's fine, by the way, I'm just explaining why we were not
understanding each other.  I'm now no longer sure why you want to do
part of this in 128-bit integers but that's probably just down to me not
knowing what you are trying to achieve.

-- 
Ben.

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Thread

Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-25 23:59 +0100
  Re: Catching overflow David Brown <david.brown@hesbynett.no> - 2018-02-26 00:32 +0100
    Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-26 01:45 +0100
  Re: Catching overflow Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-26 00:35 +0000
    Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-26 01:44 +0100
      Re: Catching overflow Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-26 01:25 +0000
        Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-26 10:53 +0100
          Re: Catching overflow Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-26 15:21 +0000
            Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-26 18:36 +0100
              Re: Catching overflow Ike Naar <ike@iceland.freeshell.org> - 2018-02-26 22:55 +0000
                Re: Catching overflow Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-26 21:59 -0800
                Re: Catching overflow David Brown <david.brown@hesbynett.no> - 2018-02-27 09:30 +0100
                Re: Catching overflow Tim Rentsch <txr@alumni.caltech.edu> - 2018-03-03 02:17 -0800
                Re: Catching overflow Steven Petruzzellis <frelwizzen@gmail.com> - 2018-03-03 03:19 -0800
                Re: Catching overflow asetofsymbols@gmail.com - 2018-03-03 03:20 -0800
                Re: Catching overflow Steven Petruzzellis <frelwizzen@gmail.com> - 2018-03-03 03:50 -0800
                Re: Catching overflow David Brown <david.brown@hesbynett.no> - 2018-03-04 13:48 +0100
                Re: Catching overflow asetofsymbols@gmail.com - 2018-03-04 07:11 -0800
                Re: Catching overflow Ike Naar <ike@iceland.freeshell.org> - 2018-03-11 09:21 +0000
                Re: Catching overflow Ike Naar <ike@iceland.freeshell.org> - 2018-03-11 09:26 +0000
                Re: Catching overflow Tim Rentsch <txr@alumni.caltech.edu> - 2018-03-26 22:36 -0700
                Re: Catching overflow David Brown <david.brown@hesbynett.no> - 2018-03-27 15:15 +0200
                Re: Catching overflow Steven Petruzzellis <frelwizzen@gmail.com> - 2018-03-27 06:26 -0700
              Re: Catching overflow Ike Naar <ike@iceland.freeshell.org> - 2018-02-27 19:41 +0000
                Re: Catching overflow Ike Naar <ike@iceland.freeshell.org> - 2018-02-27 20:14 +0000
                Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-27 22:03 +0100
            Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-26 18:40 +0100
              Re: Catching overflow Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-26 18:31 +0000
      Re: Catching overflow Steve Carroll <frelwizzen@gmail.com> - 2018-03-01 08:45 -0800
  Re: Catching overflow bartc <bc@freeuk.com> - 2018-02-26 01:12 +0000
    Re: Catching overflow Richard Damon <Richard@Damon-Family.org> - 2018-02-25 23:10 -0500
  Catching overflow asetofsymbols@gmail.com - 2018-02-25 22:09 -0800
  Catching overflow asetofsymbols@gmail.com - 2018-02-25 23:30 -0800
    Catching overflow asetofsymbols@gmail.com - 2018-02-25 23:31 -0800
    Catching overflow asetofsymbols@gmail.com - 2018-02-28 00:03 -0800
      Catching overflow asetofsymbols@gmail.com - 2018-02-28 22:49 -0800
  Re: Catching overflow "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-26 23:37 +0800
    Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-26 18:33 +0100
      Re: Catching overflow "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-28 22:31 +0800
        Re: Catching overflow "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-28 22:33 +0800
      Re: Catching overflow already5chosen@yahoo.com - 2018-03-01 02:31 -0800
        Re: Catching overflow asetofsymbols@gmail.com - 2018-03-01 05:45 -0800
          Re: Catching overflow already5chosen@yahoo.com - 2018-03-01 08:24 -0800
            Re: Catching overflow asetofsymbols@gmail.com - 2018-03-01 09:03 -0800
              Re: Catching overflow Steve Carroll <frelwizzen@gmail.com> - 2018-03-01 09:32 -0800
            Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-03-01 19:47 +0100
              Re: Catching overflow already5chosen@yahoo.com - 2018-03-01 10:58 -0800
                Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-03-01 20:08 +0100
                Re: Catching overflow already5chosen@yahoo.com - 2018-03-01 11:14 -0800
                Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-03-01 20:50 +0100
                Re: Catching overflow already5chosen@yahoo.com - 2018-03-01 12:18 -0800
            Re: Catching overflow supercat@casperkitty.com - 2018-03-03 15:08 -0800
  Re: Catching overflow jladasky@itu.edu - 2018-02-26 13:07 -0800
    Re: Catching overflow jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-26 22:44 +0100

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