Re: Motion 31: V04.2 Revision of proposed Level 1 text
On 2012-02-15 11:39:44 -0800, Dan Zuras Intervals wrote:
> > Date: Wed, 15 Feb 2012 15:31:21 +0100
> > From: Vincent Lefevre <vincent@xxxxxxxxxx>
> > To: stds-1788 <stds-1788@xxxxxxxxxxxxxxxxx>
> > Subject: Re: Motion 31: V04.2 Revision of proposed Level 1 text
> >
> > On 2012-02-13 12:16:44 +0100, Ulrich Kulisch wrote:
> > > . . .
> >
> > > Let me make another remark: Arithmetic for extended real
> > > intervals (closed and connected sets of real numbers) is free of
> > > exceptions. So a standard for interval arithmetic could be
> > > greatly simplified by a more strict separation form IEEE754 for
> > > floating-point arithmetic (no automatic type transfer from
> > > floating-point to interval).
> >
> > I don't disgree with that (if I understand what you mean).
> >
> Aside from my own opinions on the matter, this is a very
> good reason for keeping NaNs out of the level 2 structure
> of 1788. I just can't figure out how in all cases. - Dan
One could say: NaN if supported, otherwise an implementation-defined
behavior.
--
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)