Customer exit for calweek is not working

Question

Hi,
I have written a customer exit to derive calweek from a calday. But its not displaying the correct value.
Can u please let me know if there is any error in the code.  The return value for calweek is a single value.
CASE I_VNAM.
WHEN 'zfclweek'.
DATA : zday like sy-datum.
IF I_STEP = 2.
      LOOP AT I_T_VAR_RANGE INTO L_S_VAR
      WHERE VNAM = 'ZFCLDAY'. ((ZFCLDAY  is also a customer exit to derive date and its working fine )
ENDLOOP.
        zday = L_S_VAR-LOW .
        zday = zday + 1.  ( i need week of the next day of ZFCLDAY )
CALL FUNCTION 'DATE_GET_WEEK'
        EXPORTING
          DATE               = zday
       IMPORTING
          WEEK               = xweek
      EXCEPTIONS
       DATE_INVALID       = 1
OTHERS             = 2
      IF SY-SUBRC <> 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
        WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
      ENDIF.
      l_s_range-low  = xweek.
      l_s_range-sign = 'I'.
      l_s_range-opt  = 'EQ'.
      append l_s_range to e_t_range.
exit.
    endif.
    clear l_s_range.
    clear zday.
    clear xweek.
endcase.

Answer 1

Hi,
  I have changed my code as follows. But when i run the report its showing, "variable contains invalid values :
please do me the needful.
CASE I_VNAM.
WHEN 'zfcweek'.   " it is a customer exit variable on calweek
IF I_STEP = 2.
LOOP AT I_T_VAR_RANGE INTO L_S_VAR
WHERE VNAM = '0fper'.    " curent fiscal period
endloop.
YEAR = L_S_VAR-LOW+0(4) .
        PER = L_S_VAR-LOW+4(3).
        IF per = 01.
             per = 12.
             year = year - 1.
         else.
        PER = PER - 1.
        endif.
        CALL FUNCTION 'FIRST_DAY_IN_PERIOD_GET'   " need to calculate first day of last fiscal period
          EXPORTING
            I_GJAHR              =  YEAR
            I_PERIV              = 'Z1'
            I_POPER              = PER
  I_MONMIT             = 00
         IMPORTING
           E_DATE               =   FDAY.
EXCEPTIONS
  INPUT_FALSE          = 1
  T009_NOTFOUND        = 2
  T009B_NOTFOUND       = 3
  OTHERS               = 4
        IF SY-SUBRC <> 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
        WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
        ENDIF.
        CALL FUNCTION 'DATE_GET_WEEK'                  " to calculate the calweek of the first day of last fiscal period
        EXPORTING
          DATE               = FDAY
       IMPORTING
          WEEK               = xweek
       EXCEPTIONS
         DATE_INVALID       = 1
OTHERS             = 2
      IF SY-SUBRC <> 0.
MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
        WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
      ENDIF.
      l_s_range-low  = xweek .
      l_s_range-sign = 'I'.
      l_s_range-opt  = 'EQ'.
      append l_s_range to e_t_range.
    endif.
    clear l_s_range.
    clear year.
    clear fday.
    clear per.
endcase.