1. The problem statement, all variables and given/known data #1 in the attachment 2. Relevant equations 3. The attempt at a solution My code is working for all of the numeric, logical, character portions. I got 7/8 points Code (Text): if ischar(X_input) Y_output = upper(X_input); elseif isnumeric(X_input) switch isnumeric(X_input) case X_input < -2 Y_output = -1./((X_input.^2) + 1); case (-2 <= X_input) & (X_input < -1) Y_output = sin(X_input); case (-1 <= X_input) & (X_input < 1) Y_output = X_input.^2; case (1 <= X_input) & (X_input < 2) Y_output = 2; case X_input >= 2 Y_output = 1./(X_input + 1); end elseif islogical(X_input) Y_output = logical(~X_input); else Y_output = NaN; end The part that I believe is wrong is the else Y_output = NaN. I don't know what to use to test because it seems like everything is logical, numerical, or a character. So I guessed an array. I tested with an array and I get no output (not NaN). Is something wrong with my synthax?