Re: Hex string literals (was Re: C23 thoughts and opinions)

From	Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups	comp.lang.c
Subject	Re: Hex string literals (was Re: C23 thoughts and opinions)
Date	2024-06-18 11:12 -0700
Organization	A noiseless patient Spider
Message-ID	<86wmmmi0hm.fsf@linuxsc.com> (permalink)
References	(16 earlier) <87iky830v7.fsf_-_@nosuchdomain.example.com> <v4pd8t$m52o$1@dont-email.me> <86v826kdxn.fsf@linuxsc.com> <20240618123940.00007f1a@yahoo.com> <v4rnfh$1a6m8$1@dont-email.me>

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bart <bc@freeuk.com> writes:

> [...] I noticed this strange discrepancy between
> between my hex floats and C's.  In C, this value:
>
>     0x12.34p10
>
> has the decimal value 18640.0; why was that?  It turns that this is:
>
>    18.203125 x 2 ** 10
>
> The main part is interpreted as actual hex;  the exponent is in
> decimal, and exponent scaling is in binary bits.  So THREE diferent
> bases are involved!
>
> In my scheme (which as I said worked for bases from 2 to 16), the
> 0x12.34p10 value would mean this:
>
>    18.203125 x 16 ** 16        ~= 3.58e20
>
> The same base is used for all parts, including the exponent, and the
> digits that are to be shifted.  After all in decimal, 12.34e10 would
> mean:
>
>    12.34 x 10 ** 10            = 123400000000.0
>
> In my language, a base 5 version 5x12.34e10  (not valid below base 5)
> would mean this (I think, as I no longer have the compiler):
>
>    7.76 x 5 ** 5               = 24250.0
>
> This has a consistency lacking in C's hex floats.

The C hex float format has benefits that your format does not.

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Thread

Re: C23 thoughts and opinions Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-14 14:30 -0700
  Re: C23 thoughts and opinions bart <bc@freeuk.com> - 2024-06-14 23:39 +0100
    Re: C23 thoughts and opinions David Brown <david.brown@hesbynett.no> - 2024-06-15 19:17 +0200
      Re: C23 thoughts and opinions bart <bc@freeuk.com> - 2024-06-15 20:27 +0100
        Re: C23 thoughts and opinions Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-15 22:39 +0000
          Re: C23 thoughts and opinions bart <bc@freeuk.com> - 2024-06-16 00:20 +0100
            Re: C23 thoughts and opinions Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-16 01:16 +0000
            Re: C23 thoughts and opinions "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2024-06-16 12:31 -0700
              Re: C23 thoughts and opinions Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-17 00:03 +0000
        Re: C23 thoughts and opinions David Brown <david.brown@hesbynett.no> - 2024-06-16 16:54 +0200
          Re: C23 thoughts and opinions bart <bc@freeuk.com> - 2024-06-16 20:00 +0100
            Re: C23 thoughts and opinions David Brown <david.brown@hesbynett.no> - 2024-06-17 10:49 +0200
            Re: C23 thoughts and opinions Michael S <already5chosen@yahoo.com> - 2024-06-17 13:18 +0300
  Re: C23 thoughts and opinions David Brown <david.brown@hesbynett.no> - 2024-06-15 17:58 +0200
    Re: C23 thoughts and opinions Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-15 22:37 +0000
      Re: C23 thoughts and opinions David Brown <david.brown@hesbynett.no> - 2024-06-16 16:55 +0200
  Hex string literals (was Re: C23 thoughts and opinions) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-16 16:48 -0700
    Re: Hex string literals (was Re: C23 thoughts and opinions) David Brown <david.brown@hesbynett.no> - 2024-06-17 11:42 +0200
      Re: Hex string literals (was Re: C23 thoughts and opinions) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-17 17:19 -0700
        Re: Hex string literals (was Re: C23 thoughts and opinions) Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-18 04:19 +0000
          Re: Hex string literals (was Re: C23 thoughts and opinions) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-17 22:39 -0700
        Re: Hex string literals (was Re: C23 thoughts and opinions) David Brown <david.brown@hesbynett.no> - 2024-06-18 15:54 +0200
          Re: Hex string literals (was Re: C23 thoughts and opinions) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-18 15:00 -0700
            Re: Hex string literals (was Re: C23 thoughts and opinions) David Brown <david.brown@hesbynett.no> - 2024-06-19 09:37 +0200
              Re: Hex string literals (was Re: C23 thoughts and opinions) Kaz Kylheku <643-408-1753@kylheku.com> - 2024-06-19 10:17 +0000
                Re: Hex string literals (was Re: C23 thoughts and opinions) Michael S <already5chosen@yahoo.com> - 2024-06-19 13:44 +0300
                Re: Hex string literals (was Re: C23 thoughts and opinions) bart <bc@freeuk.com> - 2024-06-19 11:57 +0100
                Re: Hex string literals (was Re: C23 thoughts and opinions) scott@slp53.sl.home (Scott Lurndal) - 2024-06-19 13:46 +0000
                Re: Hex string literals (was Re: C23 thoughts and opinions) Michael S <already5chosen@yahoo.com> - 2024-06-19 18:02 +0300
          Re: Hex string literals (was Re: C23 thoughts and opinions) Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-19 07:25 +0000
            Re: Hex string literals (was Re: C23 thoughts and opinions) David Brown <david.brown@hesbynett.no> - 2024-06-19 10:49 +0200
              Re: Hex string literals (was Re: C23 thoughts and opinions) Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-21 07:13 +0000
                Re: Hex string literals (was Re: C23 thoughts and opinions) David Brown <david.brown@hesbynett.no> - 2024-06-21 13:06 +0200
                Re: Hex string literals (was Re: C23 thoughts and opinions) Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-21 22:48 +0000
                Re: Hex string literals (was Re: C23 thoughts and opinions) David Brown <david.brown@hesbynett.no> - 2024-06-22 13:40 +0200
                Re: Hex string literals (was Re: C23 thoughts and opinions) James Kuyper <jameskuyper@alumni.caltech.edu> - 2024-06-21 10:15 -0400
            Re: Hex string literals (was Re: C23 thoughts and opinions) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-19 02:32 -0700
      Re: Hex string literals (was Re: C23 thoughts and opinions) Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-18 04:19 +0000
    Re: Hex string literals (was Re: C23 thoughts and opinions) Richard Kettlewell <invalid@invalid.invalid> - 2024-06-17 11:41 +0100
      Re: Hex string literals (was Re: C23 thoughts and opinions) Richard Kettlewell <invalid@invalid.invalid> - 2024-06-17 14:57 +0100
      Re: Hex string literals (was Re: C23 thoughts and opinions) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-17 18:57 -0700
        Re: Hex string literals (was Re: C23 thoughts and opinions) Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-18 08:12 +0000
        Re: Hex string literals (was Re: C23 thoughts and opinions) Richard Kettlewell <invalid@invalid.invalid> - 2024-06-18 16:14 +0100
    Re: Hex string literals (was Re: C23 thoughts and opinions) bart <bc@freeuk.com> - 2024-06-17 14:21 +0100
      Re: Hex string literals (was Re: C23 thoughts and opinions) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2024-06-17 19:20 -0700
      Re: Hex string literals (was Re: C23 thoughts and opinions) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-06-17 22:39 -0700
        Re: Hex string literals (was Re: C23 thoughts and opinions) Michael S <already5chosen@yahoo.com> - 2024-06-18 12:39 +0300
          Re: Hex string literals (was Re: C23 thoughts and opinions) bart <bc@freeuk.com> - 2024-06-18 11:28 +0100
            Re: Hex string literals (was Re: C23 thoughts and opinions) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-06-18 11:12 -0700
          Re: Hex string literals (was Re: C23 thoughts and opinions) David Brown <david.brown@hesbynett.no> - 2024-06-18 17:20 +0200
          Re: Hex string literals (was Re: C23 thoughts and opinions) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2024-06-18 11:04 -0700
          Re: Hex string literals (was Re: C23 thoughts and opinions) Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-20 06:51 +0000
      Re: Hex string literals (was Re: C23 thoughts and opinions) Kaz Kylheku <643-408-1753@kylheku.com> - 2024-06-18 09:50 +0000
        Re: Hex string literals (was Re: C23 thoughts and opinions) scott@slp53.sl.home (Scott Lurndal) - 2024-06-18 13:56 +0000
          Re: Hex string literals (was Re: C23 thoughts and opinions) David Brown <david.brown@hesbynett.no> - 2024-06-18 17:21 +0200
            Re: Hex string literals (was Re: C23 thoughts and opinions) Richard Harnden <richard.nospam@gmail.invalid> - 2024-06-18 19:25 +0100
              Re: Hex string literals (was Re: C23 thoughts and opinions) Richard Harnden <richard.nospam@gmail.invalid> - 2024-06-18 19:38 +0100
              Re: Hex string literals (was Re: C23 thoughts and opinions) Lawrence D'Oliveiro <ldo@nz.invalid> - 2024-06-21 22:49 +0000

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