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Re: Oops, restatement Motion P1788/M0037.01:MidAndRadSpecs:



Baker

It looks as though there is a consensus, will you state the revised motion and let voting proceed?

On 21 Oct 2012, at 23:56, Kreinovich, Vladik wrote:
> Rad(Empty) = NaN is good too, let us go with Michel's suggestion

I have another query, though it is about wid() so it doesn't affect this motion.

I thought that with the revised definition that (for nonempty xx = [xlo,xhi])
     wid_F(xx) = smallest F-number >= xhi-xlo
one would always have
(*)  wid_F(xx) <= 2*rad_F(xx).
But this is not so as shown by the example xx = [-.001,1.00] where F is 3-digit decimal. It gives rad=0.501, wid=1.01.

So though always wid=2*rad in exact arithmetic, both < and > can happen in finite precision.

Are we happy with this, or should we, say, adjust the definition of rad_F so that (*) always holds?

John Pryce