Motion P1788/M0037.01:MidAndRadSpecs: provisional NO
P1788
I vote NO, on the grounds that mid and rad of Empty were omitted from the motion, see my recent queries appended. I will change my vote to YES as soon as this is satisfactorily clarified.
Chair: This doesn't change what the motion currently specifies, but only adds to it, so I hope we can just carry on voting after this clarification.
IMHO the only sensible value for mid(Empty) is NaN. Any real value falsifies the Level 2 invariant mid(xx) \in xx, which holds in all other cases. For rad(Empty), I'm easy between -oo and NaN with a small preference for -oo, on the grounds that I also slightly prefer wid(Empty) to be -oo.
John Pryce
On 20 Oct 2012, at 23:30, Ralph Baker Kearfott wrote:
> The voting period herewith
> begins. Voting will continue until after Saturday, November 10, 2012.
> Voting on this motion will proceed according to the rules for
> position papers (quorum and simple majority).
> Comment can continue during voting, but the motion
> cannot be changed during voting.
On 19 Oct 2012, at 15:48, John Pryce wrote:
> What do you want midpoint(Empty) to be? Not also 0 by natural symmetry, I hope?
On 19 Oct 2012, at 18:06, John Pryce wrote:
> ... IMO the correct recipe is
> wid(xx) returns the smallest F-number ≥ the mathematical width xhi-xlo.
>
> Vladik: what is the Level 2 width of Empty? I would be happy with
>
> NaN, on the grounds that it is genuinely undefined;
> or
> -oo, on the grounds that wid(xx) = (sup xx) - (inf xx), and when
> xx=Empty, one has sup xx = -oo and inf xx = +oo.