How to delete duplicates of some specific fields in internal table

Question

i am having internal table of it_ekko.
in that i am having some data of PO no, Line Item,IR value and IR qty......
i am having data like below.
PO                        Line Item   IR Value    IR QTY 
200310051          0010         1500           4500
200310051          0010        1500           4500
200310052         0010           0                   0
200310052          0010       0               0
now where ever IR value and IR qty is present i wanted that to display only once against that PO and line item
i wanted like below
PO                        Line Item   IR Value    IR QTY 
200310051          0010         1500           4500
200310051          0010            0              0
200310052         0010             0                0
200310052          0010            0               0
Field names for IR value and IR Qty are Menge2 and dmbtr2.
How to do that.........
I cant use
Delete adjacent duplicates of it_ekko by ebeln = wa_ekko-ebeln and
                                                                      ebelp = wa_ekko-ebelp.
because i wanted that po and same line items , how many times it is like that only.....
in it_ekko table i only wanted to delete duplicates of menge2 and dmbtr2.
Pls suggest the code

Answer 1

sort itab by po item ascending.
loop at itab into wa.
at new wa-item.
if wa-qty1 ne 0 and wa-qty2 ne 0.
move wa to wa_final.
append wa_final to i_final.
endat.
endloop.
or
loop at itab into wa.
at new wa-item.
if wa-qty1 ne 0 and wa-qty2 ne 0.
write wa.
endat.
endloop.
make sure that the qty1 and qty2 is not character type , then in control statement it will replaced by *.