Re: John, Arnold? Re: Amendment to property tracking

[Arnold Neumaier <Arnold.Neumaier@xxxxxxxxxxxx>]

Ralph Baker Kearfott wrote:
> John, Arnold,
>
> Please give your opinions.
>
> Baker
>
> On 06/03/2011 09:58 AM, Nate Hayes wrote:
> > Yes.
> >
> > It is also important to remember that both FTIA and FTDIA are theories.
> > As such, all they do is make *predictions* about the result of an
> > interval expression. Neither actually *compute* anything. So even though
> > they are necessary, they are not enough for a standard.
> >
> > For FTIA, this is why P1788 passed Motion 5, which provides interval
> > arithmetic operations to compute range enclosures consistent with FTIA.
> >
> > For FTDIA, this is why P1788 should pass Motion 25, which provides the
> > necessary operations to compute decorations consistent with FTDIA.
> >
> > As I've indicated in my friendly amendment to Motion 25, we have every
> > reason to believe John and Arnold will find the proof.

Yes, we need FTDIA, since only this gives a clear semantics with which a
user can predict what happens with the decorations, and one can be sure
that nothing unexpected happens to those using the decorations only
unconsciously (which will be the default mode for unexperienced users).

I am currently proofreading John Pryce's draft for the standard's text
on decorations on level 1, which addresses the issues in a form amenable
to proof (in the annex), including the FTDIA. This will be in a form
that I can recommend for acceptance.


But I think Motion 25 is far too low level on arithmetic operations,
and on unions and intersections far from optimal for applications.
Thus I would recommend voting No to the current version of the motion.


Arnold Neumaier