Texas Instruments PLUS TI-89 - Manual (Page 117)

100 Chapter 5: Additional Home Screen Topics
05ADDLHM DOC TI-89/TI-92 Plus: Additional Home Screen Topics (English) Susan Gullord Revised: 02/23/01 10:55 AM Printed: 02/23/01 2:13 PM Page 100 of
Folders give you a convenient way to manage variables by organizing
them into related groups. For example, you can create separate
folders for different
TI -89 / TI-92 Plus applications (Math, Text Editor,
etc.) or classes.
¦ You can store a user-
defined variable in any
existing folder.
¦ A system variable or a
variable with a reserved
name, however, can be
stored in the
MAIN folder
only.
The user-defined variables in
one folder are independent of
the variables in any other
folder.
Therefore, folders can store separate sets of variables with the same
names but different values.
The system variables in the MAIN folder are always directly
accessible, regardless of the current folder.
Using Folders to Store Independent Sets of Variables
The TI - 89 / TI - 92 Plus has one built-in folder named MAIN , and
all variables are stored in that folder. By creating additional
folders, you can store independent sets of user-defined
variables (including user-defined functions).
Folders and
Variables
Note: User-defined
variables are stored in the
“current folder” unless you
specify otherwise. Refer to
“Using Variables in Different
Folders” on page 102. MAIN
System variables
User-defined
a=1, b=2, c=3
f(x)=x
3 +x 2 +x
ALG102
User-defined
b=5, c=100
f(x)=sin(x)+cos(x)
DAVE
User-defined
a=3, b=1, c=2
f(x)=x2 +6
MATH
User-defined
a=42, c=6
f(x)=3x
2 +4x+25
Variables
You cannot create a folder
within another folder.
Name of current folder
Example of variables that
can be stored in
MAIN only
Window variables
( xmin , xmax , etc.)
Table setup variables
( TblStart , @ Tbl , etc.)
Y= Editor functions
( y1(x) , etc.)