How to create sequence id for consecutive null values?

[lpy0521]

Hey there,

how can I make this happening in SAS? I have a columns called points and I would like to create sequential group id for consecutive null values

points	group
1
1
.	1
.	1
1
1
.	2
.	2
1
1
.	3
.	3
.	3

Thanks,

[s_lassen]

Something like this?

data want;
  set have;
  if _N_=1 and missing(points) then _group=1;
  if missing(points) and not missing(lag(points)) then _group+1;
  if missing(points) then group=_group;
  drop _group;
run;

[Ksharp]

data have;
input points;
cards;
1
1
.
.
1
1
.
.
1
1
.
.
.
;

data want;
 set have;
 by points notsorted;
 if first.points and missing(points) then n+1;
 if missing(points) then group=n;
 drop n;
 run;