How to stop a while loop when 'N' is entered

This is what I have so far, I would like for the code to stop when the user types 'N', but instead the program keeps repeating, how do I fix this? I have attached a picture of the original problem as well.

 % code
while 'Y'
    input('Choose any positive number to compute the factorial of: ')
    n = ans;
    f = factorial(n);
    if ans > 0
    fprintf('The factorial is: %d\n', f)
    end 
    input('Do you wish to enter an additional value? Y/N: ','s')
end

Answer 1

[Geoff Hayes]

Hi Samantha,

Your while loop will run forever as it is not dependent upon any variable, only on the fixed constant 'Y' (which is nonzero). I think that you need to capture the user response of your final input command when you ask the user whether to continue or not:

resp = input('Do you wish to enter an additional value? Y/N: ','s');

Then compare this response to 'N' or 'n' as and act accordingly:

if strcmpi(resp,'n')
    % user has typed in N or n so break out of the while loop
    break;
end

The strcmpi function ignores the case (upper or lower) of 'N' so you needn't check for either 'N' or 'n'…just the one will do.

Hope the above helps!

Geoff