My implementation of the Newtonian Square Root Approximation in Go. Part of the Go tour: http://tour.golang.org/#23

newtonianSqrtTutorial.go

package main

import (
    "fmt"
    "math"
)

const(
  ACCURACY_DELTA = 0.00000000000001 // Experiment with this value to see accuracy impact!
)

func Sqrt(x float64) float64{
    ourGuess := float64(1) // any initial guess will do!
    
    for newtonGuess := newtonIteration(x, ourGuess); math.Abs(newtonGuess-ourGuess) > ACCURACY_DELTA
    {
    	ourGuess = newtonGuess;
        newtonGuess = newtonIteration(x, ourGuess)
    }
        
    return ourGuess
}

func newtonIteration(x, z float64) float64{
    return z-(math.Pow(z,2)-x)/(2*z)
}

func main() {
    numToSqrt := float64(125030)
    fmt.Println("Newtonian Method:",Sqrt(numToSqrt))
    fmt.Println("Control Group:", math.Sqrt(numToSqrt))
}