SquareRoot.java

import java.util.Scanner;

public class SquareRoot {

    /**
    *   Program:    SquareRoot.java
    *   Purpose:    Compute square root without using sqrt function
    *   Creator:    Chris Clarke
    *   Created:    29.07.2013
    */

    public static void main(String[] args) {

        Scanner scan = new Scanner(System.in);
        System.out.print("Enter a number: ");

        String strNum = scan.nextLine();
        double theNumber = Double.parseDouble(strNum);

        System.out.println("The square root of "+theNumber+" = "
         +findSquareRoot(theNumber));
    }//end main

    public static double findSquareRoot(double theNumber) {

        double memory=2;

        for (int i=0; i<10; i++) {
            memory = ((theNumber/memory)+memory)/2;
        }

        return memory;

    }//end findSquareRoot

}//end class