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Re: [P-1788]: Re objective == infinity

I meant intervals of real numbers, i.e.,
that infinity is not actually a number.

Baker

On 09/28/2012 05:20 AM, N.M. Maclaren wrote:

On Sep 28 2012, Ralph Baker Kearfott wrote:


Does this mean we should revisit our decision that
intervals are subsets of the set of real numbers?
That would be problematical.  However, I don't
think proceeding with subsets of real numbers only
is such a huge problem.  It would probably be easier
to resolve the issue without revisiting the
issue of extended reals.


Er, I hope that you don't mean what I think you mean!
Once you get beyond simple intervals, subsets get both
mathematically hard and computationally evil.  For
example, if you have a subset [0.0,3.0),(3.0,9.0] and
transform it so that the location corresponding to 3.0
is non-representable in any normal finite arithmetic,
is that equivalent to the subset [0.0,9.0]?

Regards,
Nick Maclaren.





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Ralph Baker Kearfott,   rbk@xxxxxxxxxxxxx   (337) 482-5346 (fax)
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