If you want to limit the number of columns generated to just 3 then perhaps that is an input parameter? How do you know which variables to scan?  Perhaps that is another input parameter. * create example data ; data have; input ID $ VAR1-VAR5; cards; 101 1 1 . . 1 102 . . 1 . . 103 1 1 . . . ; run; * set parameters ; %let maxout=3 ; %let varlist = _numeric_ ; * process the file ; data want ;   set have ;   array num &varlist ;   array col (&maxout) $32 ;   do _i=1 to dim(num) until (_n=&maxout);     if num(_i) then do ;       _n=sum(_n,1);       col(_n)=vname(num(_i));     end;   end;   drop _i _n ; run; Obs ID VAR1 VAR2 VAR3 VAR4 VAR5 col1 col2 col3 1 101 1 1 . . 1 VAR1 VAR2 VAR5 2 102 . . 1 . . VAR3 3 103 1 1 . . . VAR1 VAR2 ... View more

Just another way data want;       set have;       retain X_new Y_new Z_new ;       by ID;       array now(3) X Y Z;       array three(3)X_new Y_new Z_new ;       do i=1 to 3;             if ID=lag(ID) then do;                   if now(i)^=. then three(i)=now(i);             end;       end; if last.ID then output want; drop x y z; run; ... View more