Eos (Equation Operating System) Hierarchy - Texas Instruments TI-89 Manual Book

EOS (Equation Operating System) Hierarchy

Order of Evaluation
Parentheses,
Brackets, and
Braces
568 Appendix B: Reference Information
This section describes the Equation Operating System
(EOSé) that is used by the
variables, and functions are entered in a simple,
straightforward sequence. EOS evaluates expressions and
equations using parenthetical grouping and according to the
priorities described below.
Level Operator
1 Parentheses ( ), brackets [ ], braces { }
2 Indirection (#)
3 Function calls
4 Post operators: degrees-minutes-seconds (ó,',"), factorial (!),
percentage (%), radian (ô), subscript ([ ]), transpose (
5 Exponentiation, power operator (^)
6 Negation (ë)
7 String concatenation (&)
8 Multiplication (ù), division (/)
9 Addition (+), subtraction (ì)
10 Equality relations: equal (=), not equal (ƒ or /=),
less than (<), less than or equal ( or <=), greater than (>),
greater than or equal (‚ or >=)
11 Logical
not
12 Logical
and
13 Logical , exclusive logical
or
14 Constraint "with" operator (|)
15 Store (!)
All calculations inside a pair of parentheses, brackets, or braces are
evaluated first. For example, in the expression
evaluates the portion of the expression inside the parentheses,
and then multiplies the result,
The number of opening and closing parentheses, brackets, and
braces must be the same within an expression or equation. If not, an
error message is displayed that indicates the missing element. For
example, will display the error message
(1+2)/(3+4
Note: Because the
TI-89 / TI-92 Plus
functions, a variable name followed by an expression in parentheses
is considered a "function call" instead of implied multiplication. For
example is the function
a(b+c)
expression b+c by the variable
. Numbers,
TI-89 / TI-92 Plus
xor
4(1+2)
, by .
3 4
"Missing )."
allows you to define your own
evaluated by . To multiply the
a b+c
a , use explicit multiplication:
î )
, EOS first
,
1+2
aù(b+c) .