Re: Comments on decoration ill, intersection and union
On 2012-12-14 12:29:39 +0100, Vincent Lefevre wrote:
> On 2012-12-13 16:29:52 -0600, Nathan T. Hayes wrote:
> > If we evaluate the range of the intersection of X and Y, then
> > g([0,1] intersect [2,3])
> > = g(([0,1],DAC) intersect ([2,3],DAC))
> > = g((Empty,DAC)) // Empty input!!!
> > = (Empty,DAC)
>
> But the initial input is [0,1], which is not empty ([2,3] can be
> seen as a constant or another input, depending on the context).
> One gets Empty only after the intersect operation, and since this
> is after an operation, Empty cannot be an input.
Or if you specify intersect as an operation changing its result
as an input like above, then it may be OK, but in such a case, the
intersection of any two intervals should have the decoration dac,
since an input is always dac (even Empty with your meaning of
decorations).
--
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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