topic Re: count in SAS Programming

count

Ivy — Wed, 26 Apr 2017 17:16:20 GMT

Hello,

I would like to delete the ID with more than 2 coutinous 0 value of RX. I am wondering what is efficient way to do it. Thank you very much.

ID RX

1 1

1 0

1 1

1 0

1 1

2 0

2 1

Re: count

thomp7050 — Wed, 26 Apr 2017 16:12:19 GMT

I prefer proc sql because the code/concept may be used in many applications.

For your consideration:

PROC SQL;
CREATE TABLE TOTALS AS
SELECT ID, SUM(RX) AS TOTAL FROM IDS GROUP BY ID;
QUIT;

PROC SQL;
CREATE TABLE NEWTABLE AS
SELECT * FROM IDS WHERE ID IN (SELECT ID FROM TOTALS WHERE TOTAL <=2);
QUIT;

Re: count

Ivy — Wed, 26 Apr 2017 17:18:25 GMT

Thank you, we need to consider the >= 2 continuous 0 instead of total 0 . For example, there are two 0 for ID 1, but it cannot be deleted, due to not 0 is separated.

Re: count

Tom — Wed, 26 Apr 2017 17:20:18 GMT

So want to look for two in a row? You didn't mention any variable to use for ordering so we should we assume the data is already sorted?

So two is easy. Basically if RX=0 and it is not an isolated block of just one RX=0 then you have two or more RX=0 records in a row.

Using double DOW loop you can test an ID and then in the second loop decide whether to output the records for that ID.

data want ;
 do until (last.id);
   set have ;
   by id rx notsorted ;
   if rx=0 and not (first.rx and last.rx) then any2=1;
 end;
 do until (last.id);
   set have ;
   by id rx notsorted ;
   if not any2 then output;
 end;
run;

It looks like both of your example IDs would be deleted since the both have two or more RX=0 records next to each other.