9000 DEF FN c(n)=n*n*n

which sets up the user defined function FN c(n) which returns the cube of n (the number you type into the parentheses). Now exit from NextBASIC and return to the calculator – you can now use this user defined function as if it were one of the ZX Spectrum Next's own built-in functions. For example, enter:

FN c(3)

and the calculator will print the number 27 (i.e. the cube of 3).

Exiting from the calculator

When you have finished using the calculator, press the EDIT key. The screen will change to:

 Options
< 14MHz
 Calculator
 32/64/85
 Exit
           1792K

Calculator

Fig. 55 – Calculator Options Menu

Select the Exit option to return to the opening menu. If you were working on a NextBASIC program before you started using the calculator, then you may return to the program by selecting the NextBASIC option. (If you wish to continue using the calculator, then select the Calculator option).