OT : Approximate / fast math libraries ?

[Mogens Kjaer]

Chris Jones wrote:
...
> yes, anthing is possible. However, before I go to the effort on implementing 
> something myself, I was hoping to find some OSS solution. It struck me as 
> such a common issue there must be some solution out there already...

Padé approximation:

http://list.dprg.org/archive/2007-January/030202.html

Note that you'll have to do a lot of testing on the
signs of x and y, and handle atan z for |z|>1 as
pi/2 - atan(1/z). All these steps might take longer
than the standard atan2 function.

I guess it doesn't speed up anything to do it in
fixed point.

Mogens

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Mogens Kjaer, Carlsberg A/S, Computer Department
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