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Re: CfV: S>F and F>S

From mhx@iae.nl (Marcel Hendrix)
Subject Re: CfV: S>F and F>S
Newsgroups comp.lang.forth
Message-ID <05071301958435@frunobulax.edu> (permalink)
Date 2012-08-02 22:28 +0200
References <2012Aug2.185141@mips.complang.tuwien.ac.at>
Organization Wanadoo

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anton@mips.complang.tuwien.ac.at (Anton Ertl) writes Re: CfV: S>F and F>S

> F>S     "f-to-s"        ( -- n ) ( F: r -- ) or ( r -- n )
> n is the less significant portion of the double word that would be
> produced by the word F>D applied to the floating-point value r.

iForth's F>S does not work that way. On a 32-bit system, F>S produces
at most +/-(2^31 - 1), on a 64-bit system that is +/-(2^63 - 1).

In other words  (32-bit system)
FORTH> 32e f2^x f>d drop H. $00000000 ok
FORTH> 32e f2^x f>s      H. $80000000 ok

(64-bit system)
FORTH> 32e f2^x f>d drop H. $0000000100000000 ok
FORTH> 32e f2^x f>s      H. $0000000100000000 ok

> An ambiguous condition exists if applying F>D to r would result in
> an ambiguous condition.

Isn't that kind of obvious?

-- ---------
Ballot for systems

[x] iForth conforms to ANS Forth.
[ ] already implements the proposal in full since release [ ].
[ ] implements the proposal in full in a development version.
[ ] will implement the proposal in full in release [ ].
[ ] will implement the proposal in full in some future release.
[ ] There are no plans to implement the proposal in full in [ ].
[x] will never implement the proposal in full.
-- ----------

-marcel

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Thread

CfV: S>F and F>S anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-08-02 16:51 +0000
  Re: CfV: S>F and F>S mhx@iae.nl (Marcel Hendrix) - 2012-08-02 22:28 +0200
    Re: CfV: S>F and F>S Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-02 23:36 +0200
  Re: CfV: S>F and F>S Krishna Myneni <krishna.myneni@ccreweb.org> - 2012-08-03 04:39 -0700
    Re: CfV: S>F and F>S Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-03 19:56 +0200
      Re: CfV: S>F and F>S mhx@iae.nl (Marcel Hendrix) - 2012-08-03 21:18 +0200
        Re: CfV: S>F and F>S anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-08-04 09:50 +0000
          Re: CfV: S>F and F>S Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-04 21:51 +0200
            Presence of standard words (was: CfV: S>F and F>S) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-08-05 11:07 +0000
              Re: Presence of standard words (was: CfV: S>F and F>S) stephenXXX@mpeforth.com (Stephen Pelc) - 2012-08-05 11:34 +0000
                Re: Presence of standard words (was: CfV: S>F and F>S) Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-05 13:59 +0200
                Re: Presence of standard words (was: CfV: S>F and F>S) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-08-06 11:22 +0000
        Re: CfV: S>F and F>S Krishna Myneni <krishna.myneni@ccreweb.org> - 2012-08-04 04:50 -0700
          Re: CfV: S>F and F>S stephenXXX@mpeforth.com (Stephen Pelc) - 2012-08-04 12:30 +0000
            Re: CfV: S>F and F>S C G Montgomery <cgm@physics.utoledo.edu> - 2012-08-05 09:14 -0400
          Re: CfV: S>F and F>S Bernd Paysan <bernd.paysan@gmx.de> - 2012-08-04 21:47 +0200
      Re: CfV: S>F and F>S Krishna Myneni <krishna.myneni@ccreweb.org> - 2012-08-04 05:42 -0700

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