Square Root of a Number

%% Square Root of a Number
% This code allows users to calculate the square root of a given number
%   when given an initial guess
clc, clear

a = input( 'Enter a positive number "a" to be square-rooted' );

while a <= 0
       a = input( 'Enter number that is greater than 0 \n' );
end         %while

fprintf ( 'The value of a is recorded as: %i \n', a )

x = input( 'Enter a positive number to be the initial guess of the square root' );

while x <= 0
        x = input( 'Enter a number that is greater than 0 \n');
end         %while

abs_tol  = 10^-5;
xOld = x;
while  1
   xNew = ( xOld + ( a/xOld ) )/2;
        if ( abs( xNew - xOld ) < abs_tol )
          break;
        end         %if statement
    xOld = xNew;
    fprintf ( 'The current guess for the square root is %i \n', xNew);
end             %while
fprintf( 'The actual square root of %i is %i',a,xNew)

%{
This code will print the estimate for the square root until it is in range
     of the absolute tolerance
The absolute tolerance can be edited in line 20
%}