Chapter 17: Programming 291
17PROGRM.DOC TI-89/TI-92 Plus: Programming (English) Susan Gullord Revised: 02/23/01 1:14 PM Printed: 02/23/01 2:18 PM Page 291 of 40
If you want a function or program to perform symbolic calculations,
you must use a global variable instead of a local. However, you must
be certain that the global variable does not already exist outside of
the program. The following methods can help.
¦ Refer to a global variable name, typically with two or more
characters, that is not likely to exist outside of the function or
program.
¦ Include DelVar within the function or program to delete the global
variable, if it exists, before referring to it. (DelVar does not delete
locked or archived variables.)
To Perform
Symbolic
Calculations