[ANSI-Smalltalk] Agenda items...

[Andres Valloud]

Paolo,

Sorry it took so long to answer, I've been busy as of late.  I took the
numbers from here (see Table 1):

http://babbage.cs.qc.edu/courses/cs341/IEEE-754references.html

I am not sure that the exponents chosen are putting the mantissa in [1,
2)... why would that be?  Maybe I am just missing something obvious :(...

Andres.

On Nov 14, 2007 10:12 PM, Paolo Bonzini <paolo.bonzini at lu.unisi.ch> wrote:

> Andres Valloud wrote:
> > Paolo,
> >
> > Yes, the implementation here uses 1023 and -1022.
>
> Then you put the mantissa in [1,2), not [0.5,1).
>
> > Hmmmm... I am not
> > sure about emax / emin being off by one though.  If the range goes from
> > 0 to 2047, and 0 and 2047 are taken, then that takes one off from each
> > side, and 1024 / -1021 do not balance out that way?..
>
> The available range is 1 to 2046, and the offset is for some weird
> reason 1022 (for LIA) or 1023 (for [1,2) mantissa).  Anyway, it does not
> matter to the hardware except for multiplication/division, since for
> addition and subtraction it only cares about the *difference* between
> the exponents.
>
> (I am not saying that emax/emin are off by one in the standard, but in
> VW.  Just to be sure, in GNU Smalltalk I load the emin/emax/precision
> values directly from float.h at run-time, since C is LIA-compliant.  The
> answers are -1021/1024/53).
>
> Paolo
>
> _______________________________________________
> ANSI-Smalltalk mailing list
> ANSI-Smalltalk at lists.openskills.org
> http://lists.openskills.org/cgi-bin/mailman/listinfo/ansi-smalltalk
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.openskills.org/pipermail/ansi-smalltalk/attachments/20071202/2f8e13ad/attachment.html