Java tutorial
public class Maths { /** sqrt(a^2 + b^2) without under/overflow. **/ public static double hypot(double a, double b) { double r; if (Math.abs(a) > Math.abs(b)) { r = b / a; r = Math.abs(a) * Math.sqrt(1 + r * r); } else if (b != 0) { r = a / b; r = Math.abs(b) * Math.sqrt(1 + r * r); } else { r = 0.0; } return r; } }