TOTAL NUMBER OF DUPLICATES ROWS

[Cruise]

I'd like to create a var "count" for the total number of repated rows in combination of multiple variables as shown in data "want". I know how to accomplish this using proc freq and merging output data back to original file. I wonder if i can do it in data step, as shown how my program had failed to do so below. I'm using SAS 9.4.

Could you please help with direct correction on my code below?

data have;
input id cat dog ant;
datalines;
1 1 2 3
1 1 2 3
1 1 2 3
1 1 2 3
2 2 6 0
3 3 4 5
4 4 6 7
;
run; 

data want;
input id cat dog ant count;
datalines;
1 1 2 3 4
1 1 2 3 4
1 1 2 3 4
1 1 2 3 4
2 2 6 0 1
3 3 4 5 1
4 4 6 7 1
;
run; 

PROC SORT DATA=have;
BY id;
RUN;
DATA HAVE1; SET HAVE;
RETAIN COUNT;
BY ID;
IF FIRST.ID THEN VISIT = 1; ELSE VISIT+1;
IF LAST.ID THEN COUNT=VISIT;
RUN;

[art297 · Accepted solution]

PROC SORT DATA=have;
  BY id;
RUN;

DATA HAVE1;
  do until(last.id);
    SET HAVE;
    BY ID;
    if first.id then count=1;
    else count+1;
  end;
  do until(last.id);
    SET HAVE;
    BY ID;
    output;
  end;
RUN;

Art, CEO, AnalystFinder.com

[Cruise]

Баярлалаа. Thank you.