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Topic: inconsistent refinement behavior
Replies: 4   Last Post: Jul 14, 2013 1:43 AM

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Helen Read

Posts: 145
Registered: 9/27/10
Re: inconsistent refinement behavior
Posted: Jul 11, 2013 1:57 AM
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There is nothing inconsistent about this. When you include the
assumption x>0 or x>=0, you are implicitly assuming that x is an element
of the Reals, so with either of these assumptions the result will be
Infinity rather than ComplexInfinity.

Recall that there is no ordering in the complex numbers.

On 7/10/2013 3:22 AM, Alex Krasnov wrote:
> The following behavior appears to be inconsistent:
> In: Assuming[x==0, Refine[Infinity/x]]
> Out: ComplexInfinity
> In: Assuming[x>0, Refine[Infinity/x]]
> Out: Infinity
> In: Assuming[x>=0, Refine[Infinity/x]]
> Out: Infinity
> The third example should return unrefined given the first two examples. Is
> there an explanation?
> Alex

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