Texas Instruments TI-89 Manual Book page 586

Indirection
Post Operators
Exponentiation
Negation
Constraint (|)
The indirection operator (#) converts a string to a variable or
function name. For example,
. Indirection also allows the creation and modification of
xyz
variables from inside a program. For example, if
#s1=10 .
Post operators are operators that come directly after an argument,
such as 5!, 25%, or 60ó15' 45". Arguments followed by a post operator
are evaluated at the fourth priority level. For example, in the
expression 4^3! , 3! is evaluated first. The result,
exponent of to yield
4
Exponentiation (^) and element-by-element exponentiation (.^) are
evaluated from right to left. For example, the expression
evaluated the same as
, which is .
(2^3)^2 64
To enter a negative number, press · followed by the number. Post
operations and exponentiation are performed before negation. For
example, the result of
parentheses to square a negative number such as
. Note also that negative
81
ë3! evaluates as ë(3!) .
The argument following the "with" (|) operator provides a set of
constraints that affect the evaluation of the argument preceding the
"with" operator.
creates the variable name
#("x"&"y"&"z")
.
4096
2^(3^2) to produce 512
2
ëx is a negative number, and
is different from minus
5 (ë5)
Appendix B: Reference Information
and , then
10!r "r"!s1
6 , then becomes the
is
2^3^2
. This is different from
2
ë9 =ë81 . Use
2
to produce
(ë9)
, and
5 (ì5)
569