function answer = count3s(turkey) % This function is called count3s and it will % return to the user some variable named "answer". counter = 0; % This is a variable that we are going to use to % count the number of times we find the number 3. % We must "declare" our variables before % we use them, or Matlab (and most other programming % languages get very cranky. m = size(turkey, 1); n = size(turkey, 2); for i = 1:m for j = 1:n if (turkey(i,j)==3) % When you compare two things in Matlab using if, % the two things should be enclosed in parentheses % and if you're asking "are they equal?", you should use ==, % which means "is equal to". counter = counter +1; % This increments counter if and only if the % entry is equal to 3. If it's not, Matlab simply % ignores this step. % The semicolon tells Matlab not to print anything. end end end answer = counter; % Remember that 'answer' is the value that we are % returning when the user calls this function. % Once we have finished counting, we assign "answer" % the same value as counter, and we are finished. % We rule.