How to Write COBOL COMPUTE Statement Correctly

Here’s COBOL compute statement example. You can write mathematical operations using COMPUTE.

COBOL Example to use Compute

100-MAIN-PROGRAM.
OPEN INPUT SALES-FILE
     OUTPUT CHECK-FILE
MOVE 'Y' TO ARE-THERE-MORE-RECS
MOVE SPACES TO CHECK-REC
PERFORM UNTIL ARE-THERE-MORE-RECS = 'N'
      READ SALES-FILE
      AT END
           MOVE 'N' TO ARE-THERE-MORE-RECS
      NOT AT END
          PERFORM 200-PROCESS-PARA
      END-READ
END-PERFORM
CLOSE SALES-FILE
      CHECK-FILE
STOP RUN.

200-PROCESS-PARA.
 IF SALES-IN > 100
    MULTIPLY .10 BY SALES-IN GIVING WS-COMMISSION
ELSE
    MULTIPLY .05 BY SALES-IN GIVING WS-COMMISSION
END-IF

COMPUTE AMT-OUT = SALES-IN + WS-COMMISSION
MOVE SALES-IN TO NAME-OUT
WRITE CHECK-REC.