Tour of Go #43: implement the square root function using Newton's method.

sort.go

package main

import (
	"fmt"
	"math"
)

func Sqrt(x float64) float64 {
	z := 1.0
	for i := 1; i <= 100; i++ {
		if value := z - (z * z - x) / (2 * z); math.Abs(value - z) < 0.0000001 {
			return value
		} else {
			z = value
		}
	}
	return z
}

func main() {
	fmt.Println(Sqrt(10))
}