Determining Floating Point Square Root

Question

How do I determine the square root of a floating point number? Is the Newton-Raphson method a good way? I have no hardware square root either. I also have no hardware divide

Answer 1

Probably (still) the fastest implementation for finding the inverse square root and the 10 lines of code that I adore the most.

It's based on Newton Approximation, but with a few quirks. There's even a great story around this.