[spiritplumber]

If anyone wants a fast atan2 that I wrote a while ago (2007), for making a microcontroller navigate, it's at http://robots-everywhere.com/portfolio/math/

[readerrrr]

Did you compare its speed to built in atan2 function?

I counted the cycles for you method and it comes to around 50 plus a conditional. Built in function should be around the same.

[GFK_of_xmaspast]

how's it compare to a CORDIC?

[spiritplumber]

I wrote it for the Parallax Propeller, which is slow at doing divisions - so I tried to keep those to a minimum (one, which isn't too bad).

[GFK_of_xmaspast]

With a CORDIC the only divides should be by powers of 2 in the main loop and taking out the gain factor at the end, all of which can be turned into multiplies?

[spiritplumber]

Thanks, I'm going to go back and try it :)