Differences Between Functions And Programs - Texas Instruments TI-89 Titanium User Manual

• You can create functions that expand on the TI-89 Titanium's built-in functions. You
can then use the new functions the same as any other function.
• Functions return values that can be graphed or entered in a table; programs cannot.
• You can use a function (but not a program) within an expression. For example:
ù
is valid, but not
3 func1(3)
• Because you pass arguments to a function, you can write generic functions that are
not tied to specific variable names.
You can create a function from the Home screen, but the Program Editor is more
Note:
convenient for complex, multi-line functions.

Differences Between Functions and Programs

This guidebook sometimes uses the word command as a generic reference to
instructions and functions. When writing a function, however, you must differentiate
between instructions and functions.
A user-defined function:
• Can use the following instructions only. Any others are invalid.
Cycle
For...EndFor
Lbl
Return
Programming
ù
3 prog1(3)
Define
Goto
Local
While...EndWhile
.
Exit
(all forms)
If...EndIf
Loop...EndLoop
! ( § key)
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