predictClassRFWithScores is a function, not a script. It requires three inputs. However when you call it you are not providing it with any inputs. It is just like if you call this
sin()
and then complained that you are not getting any output from the sine function. What do you expect MATLAB to do, invent some values to use?
Possibly you are clicking the green button in the ribbon. Don't. Call the function from the command line, providing it with its required input arguments. Very basic things like calling functions and defining variables (that you can use as arguments) are explained in the introductory tutorials:
