Texas Instruments PLUS TI-89 - Manual (Page 306)

Chapter 17: Programming 289
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 289 of 40
When evaluating a user-defined function or running a program, you
can specify an argument that includes the same variable that was
used to define the function or create the program. However, to avoid
Circular definition errors, you must assign a value for x or i variables
that are used in evaluating the function or running the program.
For example:
x+1 ! x
– or –
For i,i,10,1
Disp i
EndFor
Command Description
§ key Stores a value to a variable. As on the Home screen,
pressing § enters a ! symbol.
Archive Moves specified variables from RAM to user data
archive memory.
BldData Lets you create a data variable based on the graph
information entered in the Y=Editor, Window
Editor, etc.
CopyVar Copies the contents of a variable.
Define Defines a program (subroutine) or function variable
within a program.
DelFold Deletes a folder. All variables in that folder must be
deleted first.
DelVar Deletes a variable.
getFold Returns the name of the current folder.
getType Returns a string that indicates the data type ( EXPR ,
LIST , etc.) of a variable.
Local Declares one or more variables as local variables.
Lock Locks a variable so that it cannot be accidentally
changed or deleted without first being unlocked.
MoveVar Moves a variable from one folder to another.
NewData Creates a data variable whose columns consist of a
series of specified lists.
NewFold Creates a new folder.
NewPic Creates a picture variable based on a matrix.
Rename Renames a variable.
Unarchiv Moves specified variables from user data archive
memory to RAM.
Unlock Unlocks a locked variable.
Circular Definition
Errors
Variable-Related
Commands
Note: The Define, DelVar,
and Local commands are
available from the Program
Editor’s
† Var toolbar
menu.
Causes a Circular definition error message if x
or i does not have a value. The error does not
occur if x or i has already been assigned a value.