Re: Unbounded intervals
Vincent, p-1788,
On 04/26/2012 08:26 AM, Vincent Lefevre wrote:
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Actually the concept of infinity (as an element of some set) and
the concept of unbounded intervals are different concepts. You can
Yes, that was part of my observation.
specify unbounded intervals without using the concept of infinities;
for instance, I = { x in R | x>= 1 } is an unbounded interval.
However using infinities allows one to avoid the need of
distinguishing both kinds of intervals.
Yes.
And I don't think the concept of overflow should be in Level 1,
as there is no such concept in mathematical intervals.
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I don't think anyone wants the infinity to be part of an interval.
Nate wants to replace unbounded intervals by something else, but
this is unclear, as he said that this is equivalent to unbounded
intervals. So, I don't see the point of such a change.
So, do I take it that there would be no consequence to how we
actually end up defining the operations?
For the representation, using the infinity symbol is fine for me.
This is standard and well-known.
Then, is it correct that the contention is merely describing
how we think about it and what notation we use, and not what
the actual operations will be?
Baker
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