SAS - Filter

[usuario_estudo]

Hi,

I need help writing a code on Sas Enterprise Guide.

I need to make a filter keeping only the last rows marking "Flag=1" for each ID number.

As shown in the table below in blue:

ID	Flag
1000	2
1000	1
1000	9
1000	1
1000	5
1000	1
1000	1
1000	1
1000	1
2000	11
2000	12
2000	4
2000	1
2000	1
2000	3
2000	1
2000	1
2000	1

Thank you very much!

[V_27]

Hi @usuario_estudo,

I didn't followed the question fully but here is an attempt.

data have;
input ID Flag;
datalines;
1000	2
1000	1
1000	9
1000	1
1000	5
1000	1
1000	1
1000	1
1000	1
2000	11
2000	12
2000	4
2000	1
2000	1
2000	3
2000	1
2000	1
2000	1
;
run;
proc sort data=have out=new;
by ID descending Flag;
run;
data want;
set new;
by ID;
if last.ID then output;
run;

[usuario_estudo]

Thank you for the code, but it does not return the desired result.

I would like to return the following table:

ID	Flag
1000	1
1000	1
1000	1
1000	1
2000	1
2000	1
2000	1

Thank you very much! 

[Ksharp]

data have;
input ID Flag;
datalines;
1000	2
1000	1
1000	9
1000	1
1000	5
1000	1
1000	1
1000	1
1000	1
2000	11
2000	12
2000	4
2000	1
2000	1
2000	3
2000	1
2000	1
2000	1
;
run;
data want;
 do until(last.flag);
  set have;
  by id flag notsorted;
  if last.id then  found=1;
 end;
  do until(last.flag);
  set have;
  by id flag notsorted;
  if found and flag=1 then output;
 end;
 drop found;
 run;