🚀 go-pugleaf

I don't recall the details, but there are more clever ways to calculate
distance (sqrt(x^2 + y^2)), which avoid the overflow problems of the squaring
and summing. I suspect the principle is something like this (assuming x > y >=
0): dist = x * sqrt (1 + (y/x)^2). One then applies an appropriate
approximation method to this instance of sqrt (note that 0 <= y/x < 1). Of
course, if you're sure you won't overflow, and an integer result is accurate
enough for you, I'd suggest the direct method, unrolling the Newton's Method
iteration an appropriate fixed number of times by hand. (The algorithm
converges very rapidly, about doubling the number of bits on each iteration;
it is about the only approximation method with such rapid convergence.)
--

J. Eliot B. Moss, Associate Professor	Visiting Associate Professor
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