Re: Motions 5 and 6 under discussion --

[Ralph Baker Kearfott <rbk@xxxxxxxxxxxxx>]

I don't see a problem with explicitly stating something
in the standard that is deduced from other dictates (i.e. normative
parts) in the standard.  Of course, we want all dictates to be
mutually consistent.  Beyond that, redundant specification might
help clarity.

Best regards,

Baker

Arnold Neumaier wrote:
> J. Wolff v. Gudenberg schrieb:
>
> >   a short note on motion 6 section 3 .5.2
> > last paragraph:
> >  "we treat [-oo.-oo]  and [oo,oo] as having no meaning (rather than 
> > being empty)"
> >
> > This sentence introduces a 3rd kind of emptyness, emptyset and NaI are 
> > the first 2
>
> No. It is not a kind of empty set, but a semantically forbidden
> construct, since by definition, a lower bound is never +oo,
> and an upper bound never -oo.
>
>
> > I suggest to drop this sentence  and replace it by:
> > "Note that no operation ever returns [-oo.-oo]  or [oo,oo]"
>
> This is another consequence of the definition, since each operation 
> returns an interval, and [-oo.-oo] or [oo,oo] are not intervals in
> the sense of the proposal.
>
>
> > I know that this would mean to set 1/0 or Log(0) equal to the emptyset 
> > and not to infinity, that is exactly what was intended.
>
> Yes. This is another consequence of the definition,
>
>
> Arnold Neumaier


--

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R. Baker Kearfott,    rbk@xxxxxxxxxxxxx   (337) 482-5346 (fax)
(337) 482-5270 (work)                     (337) 993-1827 (home)
URL: http://interval.louisiana.edu/kearfott.html
Department of Mathematics, University of Louisiana at Lafayette
(Room 217 Maxim D. Doucet Hall, 1403 Johnston Street)
Box 4-1010, Lafayette, LA 70504-1010, USA
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