I am looking for algorithms that can convert x and y value on a Cartesian plane (x,y) to an angle. The angle can be 0-360 degrees or 0-2? radian.

Does anyone know of such algorithms?

I have looked for geometric algorithms on Google. I have also found a list of algorithms on Wikipedia, but no luck finding this particular algorithm.

Also are there search databases that solely contain algorithms?

Thank you in Advance.

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