Re: [P-1788]: Opinion about infinity
On 2012-09-28 03:22:46 -0500, Ralph Baker Kearfott wrote:
> Regarding the question of infinity vs overflow, I agree
> with Nathalie that infinity can be an input quantity,
> not just produced from overflow. Intervals can
> be described using infinity. This does not contradict
> our objects are real numbers.
Yes, for instance, to prove that some function f(x), made of library
operations, is <= 17 for any x >= 0, a solution can just be to
evaluate f([0,+inf]). Then you may or may not have an answer, but
if you have an answer, it is valid.
Example: f(x) = sin(x) + cos(x).
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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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