Converting a Script to a Function The script Squarerootm was

Converting a Script to a Function The script Squareroot.m was presented in lecture-it is also attached to this assignment and shown below. For this problem, you must convert this script m-file to a function m-file. Your new Squareroot. m function must have one input argument and one output argument. Of course, it must not prompt the user and it must not produce output to the command window. You must include a proper comment header block and you must use good programming practices. % This script computes the squareroot of a number % using the \"successive approximation method.\" % Geometrically speaking, the number can be considered to be % the area of a rectangle. This rectangle is successively made % into a square by increasing the length and decreasing the % width until they are the same (within a tolerance, of course). % The length (or width) is then the squareroot of the area. A = input(\'Enter a positive number to estimate its squareroot:\'); while A loop_tolerance old_length = new_length; new_length = (old_length + A/old_length)/2; %Note: old width = A/old_length k = k + 1; % loop counter end % Use \"fprintf\" to tightly control how your variables are displayed fprintf(\'The squareroot of %0.2f is approximately %0.6f (to a tolerance of %0.5f).\ \', A, new_length, loop_tolerance) disp([\'This estimate required \', num2str(k), \' iterations.\']) % *** TIP: Hit \"ctrl-C\" to stop a MATLAB program form running! *** % *** (For example, if you\'re caught in an \"infinite loop\") ***

Solution

% matlab code to determine square roo of a number

% This function computes the square root of a number
% using the \"successive approximation method.\"
function squareRoot = square_root(A)
   old_length = A; %initial length = A
   new_length = 1; %initial width = 1
   k = 0; % loop counter
   loop_tolerance = 0.00001;

   while abs(new_length - old_length) > loop_tolerance
       old_length = new_length;
       new_length = (old_length + A/old_length)/2;
       k = k + 1; % loop counter
   end
   squareRoot = new_length;
end

% main code, the function will be called from this main body
A = input(\'Enter a positive number to estimate its square root: \');
while A <= 0
   disp(\'Invalid entry. The number cannot be zero or negative!\')
   A = input(\'Enter a positive number to estimate its square root: \');
end
loop_tolerance = 0.00001;
% function call
squareRoot = square_root(A);
fprintf(\'The square root of %0.2f is approximately %0.6f (to a tolerance of %0.5f).\ \', A, squareRoot, loop_tolerance);

%{
output:

Enter a positive number to estimate its square root: 25
The square root of 25.00 is approximately 5.000000 (to a tolerance of 0.00001).     

Enter a positive number to estimate its square root: 46                             
The square root of 46.00 is approximately 6.782330 (to a tolerance of 0.00001).

%}