Adds the result of an expression to an accumulator variable.
Valid: |
in a DATA step
|
Category: |
Action
|
Type: |
Executable
|
-
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. |
The sum statement is equivalent
to using the SUM function and the RETAIN statement, as shown here:
retain variable 0;
variable=sum(variable,expression);
Here are examples of sum statements that illustrate
various expressions:
Copyright © 2011 by SAS Institute Inc., Cary, NC, USA. All rights reserved.