About Operators Used in Relations
The following operators can be used in relations, both in equations and in conditional statements.
Arithmetic Operators
|
+
|
Addition
|
|
–
|
Subtraction
|
|
/
|
Division
|
|
*
|
Multiplication
|
|
^
|
Exponentiation
|
|
()
|
Parentheses for grouping for example, d0 = (d1–d2)*d3
|
Assignment Operator
|
=
|
Equal to
|
The equal (=) sign is an assignment operator that equates the two sides of an equation or relation. When the equal sign is used, the equation can have only a single parameter on the left side.
Comparison Operators
Comparison operators are used when a TRUE/FALSE value can be returned. For example, the following relation returns TRUE whenever d1 is greater than or equal to 3.5. It returns FALSE whenever d1 is less than 3.5:
d1 >= 3.5
The following comparison operators are supported:
|
==
|
Equal to
|
|
>
|
Greater than
|
|
> =
|
Greater than or equal to
|
|
!=, <>,~=
|
Not equal to
|
|
<
|
Less than
|
|
<=
|
Less than or equal to
|
|
|
|
Or
|
|
&
|
And
|
|
~, !
|
Not
|
 |
The "equal to" assignment operator is different from the "equal to" comparison operator.
|
The operators |, &, !, and ~ extend the use of comparison relations by enabling several conditions to be set in a single statement. For example, the following relation returns TRUE whenever d1 is between 2 and 3, but not equal to 2.5:
d1 > 2 & d1 < 3 & d1 ~= 2.5