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Re: P1788 Clauses 1 and 2



On 2012-12-03 09:04:54 +0000, John Pryce wrote:
> On 1 Dec 2012, at 22:51, Michel Hack wrote:
> > This standard specifies ... following ... at least one floating-point
> > type defined by the IEEE-754/2008 standard.
> > 
> > When did we decide this?  We were going to have additional requirements
> > for joint compliance with 1788 and 754 *if* a 754-type was supported,
> > but I thought it was going to be possible to be 1788-compliant without
> > using 754-types.
> > 
> > I realise that the "Scope" is (I think) not really normative, but this
> > should (if *unintended*) probably be rephrased, e.g.
> > 
> >  ...and at least one fully-specified numeric type
> >     such as an IEEE-754/2008 floating-point type.

I have the same objection as Michel. Actually "specifies" used here
is incorrect because the format is specified in IEEE 754, not in
P1788. Now, a 754-format could only be optional (the point is that
there is some specification in P1788 attached to it).

> This made me search my files and I saw that what I included (with
> changes of tense) is not exactly the text in the approved PAR, but a
> slightly earlier draft. The piece of text under discussion has been
> changed in the final PAR. See below. Michel, would that text,
> delimited by **, remove your objection? (I wonder if you suggested
> that change, back in 2008?)
> 
> John Pryce
> 
> "Scope" in actual PAR, approval date 12 Jun 2008:
> > **This standard specifies basic interval arithmetic (IA) operations
> > selecting and following one of the commonly used mathematical
> > interval models. This standard supports the IEEE-754/2008 floating
> > point types of practical use in interval computations.** [...]

I think this is OK, except that I would replace "types" by "formats".

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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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