Re: [IEEE P-1788] Voting begins: Motion P1788/M0013.02:ComparisonOperations : NO
I also vote NO.
As it is now, this motion is wrong from a mathematical point of view.
On 2010-04-30 12:11:25 +0200, Dominique Lohez wrote:
> My vote is NO
>
> Rationales
>
> 1) The comparison operations SHOULD be defined at defined at level 1
> and then developed at level 2 and further
> Such an approach would be consistent with the the methodology
> alway used in the working group up to now
I agree, and moreover, comparisons must be completely defined, in
particular concerning the empty set. I don't see how { IFF bar, <= }
can be a lattice, as the empty set is taken into account.
The motion says:
The greatest lower bound and the least upper bound of an interval
with the empty set are both the empty set.
So, this would mean that X <= Empty and Empty <= X for any X, but
with the consequence that <= would no longer be an order relation
(since no antisymmetric).
I think that X <= Empty and Empty <= X should be false for any
non-empty X. If defined as operations of P1788, glb and lub
should return NaI on (X,Empty).
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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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