230 FN function Purpose FN preceding a variable name indicates that it is being used as the name of a function. Both string and numeric functions may be defined. See the keyword DEF and chapters 17 and 18 for a more detailed description of functions and procedures. Since a function always returns a value. It often appears on the right of an equal sign or in a print statement. Procedures, on the other hand, do not return results. Example 1000 DEF FNmean2(x,y)=(x+y)/2 Description A reserved word used at the start of all user defined functions. Syntax DEF FN [( | {, | var> } )] Associated keywords ENDPROC , DEF , LOCAL