user manual

A-26 Tables and Reference Information
The variables listed below are used by the TI
-
80 in various ways. Some have
restrictions on their use.
The variables
A
through
Z
and
q
can hold only numbers—
either decimals or fractions. You may store to these variables.
The TI
-
80 can update
X
,
Y
, and
T
during graphing; therefore,
you may wish to reserve those variables for graphing
activities.
The variables
L
ã
through
L6
are defined as lists. You cannot
store another type of data to them.
You can store any string of characters, functions, instructions,
or variable names to the functions
Y
n
(in
FUNC
mode) and
X
n
î
and
Y
n
î
(in
PARAM
mode), by using either
§
or the
Y=
editor. The validity of the string is determined when the
function is evaluated.
The values of the Window variables

XMIN
,
XMAX
,
XSCL
,
@
X
,
TSTEP,
etc.

must be real numbers. You may store to
them. Since the TI
-
80 can update some of them, as the result
of a Zoom instruction, for example, you may wish to reserve
these variables for graphing activities.
The statistical result variables
n
,
v
,
MINX
,
G
X
,
a
,
r
,
REGEQ
,
X1
,
Y1
,
Q1
,
MED
,
Q3
, etc.

are reserved for use by the TI
-
80.
You cannot store to them.
TI-80 Variables
User Variables
System
Variables