How do I get execute while else loop?

Hello. I am trying to create a loop that when userinput == 'yes' for the question to continue, it will run the questions. But if the userinput == 'no', I want it to print 'Thank you'.

I am having trouble to get the code to execute the part when userinput == 'no'.

answer = 'yes';
if answer == 'yes'
  while (answer == 'yes')
    dia = input('Enter the circle diameter : ');
    choice = input('Enter your choice : ');

   if choice == 1
     area = pi * (dia/2)^2;
     fprintf('Area of circle = %.1f \n', area);
  
   elseif choice == 2
     circum = pi * dia;
     fprintf('Circumference of circle = %.1f \n', circum);

    else
      fprintf('Invalid choice \n'); 
    end
  answer = input('Do you want to continue? [yes/no] : ', 's');
  end
else
  fprintf('Thank you');
end  

Answer 1

[Jan]

The == operator compares its arguments elementwise. This works only if one of the array is a scalar or if bother have the same size.

Use strcmp to compare CHAR vectors. The == operator works with strings:

answer = 'yes';
if strcmp(answer, 'yes')
  while strcmp(answer, 'yes')

Or

answer = "yes";   % Double quotes!
if answer == "yes"
  while answer == "yes"