Operators in expressions

Operators are used in expressions to indicate an action to be performed on the operands in the expression or the relationship between the operands.

There are four kinds of operators, one for each of the four types of expressions:

Arithmetic operators (+, -, *, /)
Character operator (||, |>, |<)
Logical operators (&, |, ¬)
Relational operators (=, >, <, >=, <=, ¬=, ¬>, ¬<)

Each operator must be between the operands of the expression in which it is used; for example, (&A + 4). Operators can be specified as a predefined value (for example, *EQ) or as a symbol (for example, =).

All predefined value operators must have a blank on each side of the operator:
```
(&VAR *EQ 7)
```
Except for the division operator (/), symbolic operators need no blanks on either side. For example, either (&VAR=7) or (&VAR = 7) is valid.
Where the division operator follows a variable name, the division operator must be preceded by a blank. For example, (&VAR / 5) or (&VAR /5) is valid; (&VAR/5) is not valid.

The following character combinations are the predefined values and symbols that represent the four kinds of operators; they should not be used in unquoted strings for any other purpose.

Table 1. Predefined values and symbols representing the four kinds of operators
Predefined Value	Predefined Symbol	Meaning	Type
	+	Addition	Arithmetic operator
	-	Subtraction	Arithmetic operator
	*	Multiplication	Arithmetic operator
	/	Division	Arithmetic operator
*CAT	\|\| ¹	Concatenation	Character string operator
*BCAT	\|> ¹	Blank insertion with concatenation	Character string operator
*TCAT	\|< ¹	Blank truncation with concatenation	Character string operator
*AND	&	AND	Logical operator
*OR	\| ¹	OR	Logical operator
*NOT	¬ ²	NOT	Logical operator
*EQ	=	Equal	Relational operator
*GT	>	Greater than	Relational operator
*LT	<	Less than	Relational operator
*GE	>=	Greater than or equal	Relational operator
*LE	<=	Less than or equal	Relational operator
*NE	¬= ₂	Not equal	Relational operator
*NG	¬> ₂	Not greater than	Relational operator
*NL	¬< ₂	Not less than	Relational operator
Note: In some national character sets and in the multinational character set, the character \| (hexadecimal 4F) is replaced by the character ! (exclamation point). Either ! or OR can be used as the OR operator and either \|\| or CAT, !> or BCAT, and !< or TCAT can be used for concatenation in those character sets. In some national character sets and in the multinational character set, the character ¬ (hexadecimal 5F) is replaced by the character . Either or *NOT can be used as the NOT operator in those character sets.