Sum statement (not sum function) question?

[Mirisage]

Hi Forum,

Could anyone help me to undestand the red colored piece of this code?

/*Sorting in preparation for "By-group processing" - I understand this  */

PROC SORT DATA=A;

BY ID_NUM;

run;

/*By-group processing- I understand this  */

DATA A1 A2;

   SET A  ;

   BY ID_NUM;

   RETAIN LOAN_RECEIVER 0;

   LOAN_RECEIVER + 1; /*Sum statement (not sum function) which returns accumulated total, am I correct?*/

   IF FIRST.ID_NUM THEN LOAN_RECEIVER = 1;

   IF LOAN_RECEIVER = 1 THEN OUTPUT A1;

   ELSE IF LOAN_RECEIVER = 2 THEN OUTPUT A2;

RUN;

Q:

LOAN_RECEIVER + 1; is the Sum statement (not sum function) which returns accumulated total, am I correct?

Thanks

Miris

[LinusH]

Yes you are correct.The retain statement is unnecessary since variables in a sum statement are retained by default.

[PGStats · Accepted solution]

Miris,

The LOAN_RECEIVER + 1; statement is just equivalent to LOAN_RECEIVER = LOAN_RECEIVER + 1;, except for two side effects that are implied by LOAN_RECEIVER being the target of the sum statement. First, LOAN_RECEIVER value is RETAINed from one iteration to the next, second, LOAN_RECEIVER is initialized with zero.

So, you see, the statement RETAIN LOAN_RECEIVER 0; is not needed at all, as both statement's effects are already implied. Try removing it. you should see no change.

PG