Sum Statement

Adds the result of an expression to an accumulator variable

Valid: in a DATA step

Category: Action

Type: Executable

Syntax

variable + expression ;

Arguments

variable

• specifies the name of the accumulator variable, which contains a numeric value.

• Tip: The variable is automatically set to 0 before SAS reads the first observation. The variable s value is retained from one iteration to the next , as if it had appeared in a RETAIN statement.

• Tip: To initialize a sum variable to a value other than 0, include it in a RETAIN statement with an initial value.

expression

• is any SAS expression.

• Tip: The expression is evaluated and the result added to the accumulator variable.

• Tip: SAS treats an expression that produces a missing value as zero.

Comparisons

The sum statement is equivalent to using the SUM function and the RETAIN statement, as shown here:

 retain  variable  0;  variable  =sum(  variable  ,  expression  ); 

Examples

Here are examples of sum statements that illustrate various expressions:

• balance+( ˆ’ debit);

• sumxsq+x*x;

• nx+(x ne .);

• if status='ready' then OK+1;

See Also

Function:

• SUM Function on page 843

Statement:

• RETAIN Statement on page 1381