Texas Instruments TI-80 Calculator User Manual


 
2-16 Math, Angle, and Test Operations
To display the TEST menu, press
2
D
. When you select from the menu, the
name is copied to the cursor location. These functions are valid for lists; they
return a list calculated on an element-by-element basis.
TEST
True if:
1:=
Equal.
2:
ƒ
Not equal to.
3:>
Greater than.
4:
Greater than or equal to.
5:<
Less than.
6:
Less than or equal to.
Relational operators compare
valueA
and
valueB
and return
1
if the test is true or
0
if the test is false.
valueA
and
valueB
can
be numbers, expressions, or lists.
Relational operators are often used in programs to control
program flow and in graphing to control the graph of a
function over specific values.
valueA
=
valueB
valueA
ƒ
valueB
valueA
>
valueB
valueA
valueB
valueA
<
valueB
valueA
valueB
Relational operators are evaluated after mathematical
functions according to EOS rules (Chapter 1).
¦
The expression
2+2=2+3
returns
0
. The TI
-
80 does the
addition first because of EOS rules, and then it compares 4
to 5.
¦
The expression
2+(2=2)+3
returns
6
. The TI
-
80 first
performs the relational test because it is in parentheses;
then it adds 2, 1, and 3.
TEST (Relational) Operations
TEST Menu
=
ƒ
>
<
Using Tests