Improvement to the Program

It would be nice if the user could enter the number for which the square root is computed.

Here is the familiar program fragment that asks the user to enter a floating point value:

    // get the number from the user
    Scanner scan = new Scanner( System.in );
    System.out.println("Enter the number:"); 
    N = scan.nextDouble();

Here is the program as it currently stands:

class  SquareRoot
{

  public static void main( String[] args ) 
  {
    final double smallValue = 1.0E-14 ;
    double N     = 3.00 ;
    double guess = 1.00 ;

    while ( Math.abs( N/(guess*guess) - 1.0 ) > smallValue )
    {      
       guess =  N/(2*guess) + guess/2 ; // calculate a new value for the guess
    }

    System.out.println("The square root of " + N + " is " + guess ) ;
  }
}