SUM Method
Retrieves the summary value for a given key from
the hash table and stores the value in a DATA step variable.
Syntax
Required Arguments
rc
specifies whether the
method succeeded or failed.
A return code of zero
indicates success; a nonzero value indicates failure. If you do not
supply a return code variable for the method call and the method fails,
then an appropriate error message is written to the log.
object
specifies the name
of the hash object.
KEY: keyvalue
specifies the key value
whose type must match the corresponding key variable that is specified
in a DEFINEKEY method call.
The number of “KEY: keyvalue”
pairs depends on the number of key variables that you define by using
the DEFINEKEY method.
SUM: variable-name
specifies a DATA step
variable that stores the current summary value of a given key.
Details
You
use the SUM method to retrieve key summaries from the hash object.
For more
information, see Maintaining Key Summaries in SAS Language Reference: Concepts.
Comparisons
The SUM method retrieves
the summary value for a given key when only one data item exists per
key. The SUMDUP method retrieves the summary value for the current
data item of the current key when more than one data item exists for
a key.
Example: Retrieving the Key Summary for a Given Key
The following example
uses the SUM method to retrieve the key summary for each given key,
K=99 and K=100.
k = 99;
count = 1;
h.add();
/* key=99 summary is now 1 */
k = 100;
h.add();
/* key=100 summary is now 1 */
k = 99;
h.find();
/* key=99 summary is now 2 */
count = 2;
h.find();
/* key=99 summary is now 4 */
k = 100;
h.find();
/* key=100 summary is now 3 */
h.sum(sum: total);
put 'total for key 100 = ' total;
k = 99;
h.sum(sum:total);
put 'total for key 99 = ' total;
run;
The first PUT statement
prints the summary for k=100:
total for key 100 = 3
The
second PUT statement prints the summary for k=99:
total for key 99 = 4