Re: -0 and +0
On 2013-04-25 05:50:08 -0500, Ralph Baker Kearfott wrote:
> At this point, I will need to review all of our motions; perhaps
> someone can help remind me. I vaguely recall we decided we would
> have only one 0, and not -0 and +0 in the standard. (Of course,
> this would not mean implementers could not use this 754 feature
> in implementing 1788.)
This is a bit meaningless: What does "have only one 0" mean? At
which level? ...
AFAIK, the main point that was decided about this is Motion 3,
which says:
The P1788 Interval arithmetic standard defines intervals as
closed and connected sets of real numbers.
That means that ±Infinity may be used to denote an unbounded
interval but are never considered as members of an interval.
This is at Level 1 and Level 2. Representation (Level 3) is another
matter, where you can't ignore that a number format may have signed
zeros...
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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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