Though, it is possible to have more than one function in a given M-file. For illustration, if one function calls the other, the first function would be the primary function, and the function which is termed as the subfunction. Such functions both would be stored in the similar M file-first the primary function and then the subfunction. The name of the M-file would be similar as the name of the primary function, to avoid the confusion.
To elaborate this, a program which is similar to the earlier one, but computes and prints the area of a rectangle, this is as shown here. The script, or main program, first calls a function which reads the length and width of the rectangle, and then calls the function to print results. This function calls a subfunction to compute the area.