Please check out this code:
* determine subtotals
REFRESH IZSTAB.
SELECT * INTO TABLE IZSTAB
FROM T683S
WHERE KVEWE = 'A' AND
KAPPL = I_APPLICATION (value is 'V') AND
KALSM = I_PRICING_PROCEDURE AND
KSCHL = SPACE
ORDER BY PRIMARY KEY.
XKALSM = I_PRICING_PROCEDURE.
* determine from/to steps
REFRESH LT_SNTAB.
SELECT * INTO CORRESPONDING FIELDS OF TABLE LT_SNTAB
FROM T683S
WHERE KVEWE = 'A' AND
KAPPL = I_APPLICATION AND
KALSM = XKALSM ORDER BY PRIMARY KEY.
SORT LT_SNTAB BY KSCHL.
XKOMV_KEY-MANDT = SY-MANDT.
XKOMV_KEY-KNUMV = KEY_KNUMV.
XKOMV_KEY-KPOSN = KEY_KPOSN.
READ TABLE XKOMV WITH KEY XKOMV_KEY BINARY SEARCH.
IF SY-SUBRC IS INITIAL.
IXKOMV_TABIX = SY-TABIX.
LOOP AT XKOMV FROM IXKOMV_TABIX.
IF XKOMV-KNUMV = XKOMV_KEY-KNUMV AND
XKOMV-KPOSN = XKOMV_KEY-KPOSN.
IF XKOMV-KOAID NE 'D'.
IF XKOMV-KSTAT IS INITIAL.
IF NOT XMWSK1 IS INITIAL AND XKOMV-MWSK1 NE XMWSK1.
XKOMV-MWSK1 = XMWSK1.
MODIFY XKOMV.
O_KONV_CHANGED = 'X'.
ELSE.
CONTINUE.
ENDIF.
ENDIF.
ELSE.
CHECK XKOMV-KINAK IS INITIAL.
IF XKOMV-IX_KOMT1 IS INITIAL.
READ TABLE LT_SNTAB WITH KEY KSCHL = XKOMV-KSCHL
BINARY SEARCH.
IF SY-SUBRC IS INITIAL.
XKOMV-STUNB = LT_SNTAB-STUNB.
XKOMV-STUN2 = LT_SNTAB-STUN2.
ENDIF.
ENDIF.
YMWSK1 = XKOMV-MWSK1.
LA_TAX = SY-TABIX.
XMWSK1 = XKOMV-MWSK1.
XMWSK2 = XKOMV-MWSK2.
XSTUNR = XKOMV-STUNB.
XSTUN2 = XKOMV-STUN2.
IF XSTUN2 LT XSTUNR.
XSTUN2 = XSTUNR.
ENDIF.
IF XSTUN2 = 0.
XSTUN2 = XKOMV-STUNR.
ENDIF.
KOMV_KEY-MANDT = SY-MANDT.
KOMV_KEY-KNUMV = KEY_KNUMV.
KOMV_KEY-KPOSN = KEY_KPOSN.
KOMV_KEY-STUNR = XSTUNR.
KOMV_KEY-ZAEHK = 0.
* Check if reference field refers to a subtotal
READ TABLE IZSTAB WITH KEY KVEWE = 'A'
KAPPL = I_APPLICATION
KALSM = XKALSM
STUNR = XSTUNR
BINARY SEARCH.
BEZUG_IST_ZWISU = NO.
IF SY-SUBRC IS INITIAL.
BEZUG_IST_ZWISU = YES.
ENDIF.
READ TABLE XKOMV WITH KEY KOMV_KEY BINARY SEARCH.
IF SY-SUBRC LT 8.
READ TABLE XKOMV INDEX SY-TABIX.
IF XKOMV-STUNR GT XSTUN2 AND BEZUG_IST_ZWISU = NO.
CONTINUE.
ELSE.
XKOMV_KEY-MANDT = SY-MANDT.
XKOMV_KEY-KNUMV = KEY_KNUMV.
XKOMV_KEY-KPOSN = KEY_KPOSN.
READ TABLE XKOMV WITH KEY XKOMV_KEY BINARY SEARCH.
CHECK SY-SUBRC IS INITIAL.
LOOP AT XKOMV FROM SY-TABIX.
IF XKOMV-KNUMV = XKOMV_KEY-KNUMV AND
XKOMV-KPOSN = XKOMV_KEY-KPOSN.
IF XKOMV-STUNR GT XSTUN2.
CONTINUE.
ENDIF.
SELECT SINGLE * FROM T685A WHERE KAPPL = XKOMV-KAPPL
AND KSCHL = XKOMV-KSCHL.
IF BEZUG_IST_ZWISU = YES AND
XMWSK1 NE SPACE AND
( XKOMV-KSTAT = SPACE OR XKOMV-KNTYP = 'R'
OR T685A-KRELI = 'X' ) AND
XKOMV-KOAID NE 'D' .
IF ( XKOMV-MWSK1 NE XMWSK1 ) OR
( XKOMV-MWSK2 NE XMWSK2 ).
XKOMV-MWSK1 = XMWSK1.
XKOMV-MWSK2 = XMWSK2.
MODIFY XKOMV.
O_KONV_CHANGED = 'X'.
ENDIF.
ENDIF.
IF XKOMV-STUNR GE XSTUNR AND
XKOMV-STUNR LE XSTUN2 AND
XKOMV-KINAK NA 'AMX'.
IF BEZUG_IST_ZWISU = NO AND
XMWSK1 NE SPACE AND
( XKOMV-KSTAT = SPACE OR XKOMV-KNTYP = 'R'
OR T685A-KRELI = 'X' ) AND
XKOMV-KOAID NE 'D' .
IF ( XKOMV-MWSK1 NE XMWSK1 ) OR
( XKOMV-MWSK2 NE XMWSK2 ).
XKOMV-MWSK1 = XMWSK1.
XKOMV-MWSK2 = XMWSK2.
MODIFY XKOMV.
O_KONV_CHANGED = 'X'.
ENDIF.
ENDIF.
ENDIF.
ELSE.
EXIT.
ENDIF.
ENDLOOP.
ENDIF.
ENDIF.
ENDIF.
ELSE.
EXIT.
ENDIF.
ENDLOOP.
ENDIF.
Bluesky
