Can math.atan2 return INF?

Pierre-Alain Dorange pdorange at pas-de-pub-merci.mac.com
Tue Jun 21 14:01:38 EDT 2016


Steven D'Aprano <steve at pearwood.info> wrote:

> Are there any circumstances where math.atan2(a, b) can return an infinity?
> 
> I know it will return a NAN under some circumstances.

atan or atan2 can't return INFINITE, it was the arc tangent of a value,
then arc tangent can only be between -PI and +PI (is was an angle).

I do not know under what circumstance atan2 can return NAN, atan2 taks 2
argument (y and x) and return the angle corresponding to y/x.
If x is 0.0, atan2 return 0.0 (do not try to make the division).

atan2 was used over atan to optimize and so that it can used the correct
quadrant (for angle answer).

-- 
Pierre-Alain Dorange        <http://microwar.sourceforge.net/>

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