Printing matrix to display error message, why?

Can someone tell me why this error occurs please?

Input

M =  0     0     0     0     0     0     0
     2     1     1     0     0     0     0
     2     2     2     2     1     2     1
     2     1     1     1     2     1     1
     1     1     2     2     2     2     1
     1     1     1     1     2     2     2

Function

function printMatrix(M)

[rows, cols] = size(M);


sep_row = [repelem('-', cols*2+1), '\n'];

fprintf(sep_row);
for r = 1:rows
    
    fprintf('|');
    
    for c = 1:cols
        
        if M(r,c) == 1
            char = 'x';
        elseif M(r,c) == 2
            char = 'o';
        else
            char = ' ';
        end
        
        fprintf([char, '|']);
        
    end
    fprintf('\n');
end

fprintf(sep_row);

end

Error output

Error using printMatrix
Too many output arguments.

Answer 1

[ME]

I just copied and pasted your code exactly as it appears above and it runs absolutely fine for me.

Can you provide any more details that might help us understand where this is failing for you?

Answer 2

[Stephen23]

The error message "Error using printMatrix Too many output arguments" tells us that you tried to call the function printMatrix with an output argument.... but the function printMatrix you showed in your question does not have any outputs, so trying to do this will throw an error.

Here is a simpler way of generating the printed character matrix:

>> Z = repmat('|',6,15);
>> V = ' xo';
>> Z(:,2:2:end) = V(M+1)
Z =
| | | | | | | |
|o|x|x| | | | |
|o|o|o|o|x|o|x|
|o|x|x|x|o|x|x|
|x|x|o|o|o|o|x|
|x|x|x|x|o|o|o|