Chapter 7: Expressions

Definitions for SAS Expressions

expression

• is generally a sequence of operands and operators that form a set of instructions that are performed to produce a resulting value. You use expressions in SAS program statements to create variables, assign values, calculate new values, transform variables , and perform conditional processing. SAS expressions can resolve to numeric values, character values, or Boolean values.

operands

• are constants or variables that can be numeric or character.

operators

• are symbols that represent a comparison, arithmetic calculation, or logical operation; a SAS function; or grouping parentheses.

simple expression

• is an expression with no more than one operator. A simple expression can consist of a single

  • constant

  • variable

  • function.

compound expression

• is an expression that includes several operators. When SAS encounters a compound expression, it follows rules to determine the order in which to evaluate each part of the expression.

WHERE expressions

• is a type of SAS expression that is used within a WHERE statement or WHERE= data set option to specify a condition for selecting observations for processing in a DATA or PROC step. For syntax and further information on WHERE expressions, see Chapter 12, 'WHERE-Expression Processing,' on page 197 and SAS Language Reference: Dictionary