Problem to define a chk column

[Rakeon]

Hi,

Hi have this table:

COD  FLAG

1          N

1          N

1          S

2          N

2          N

3          S

3          N;

I need to create a new table with a new column (chk) that verify the variation of FLAG Variable in the same group of COD coloumn:

if FLAG change in the same group of COD, the variable chk is set to 1 to all group of cod:

here there is the example:

COD  FLAG         CHK

1         N                   1

1         N                   1

1         S                   1

2         N                   0

2         N                   0

3         S                    1   

3         N                    1

I create this sas code:

data mytable;

     retain _flag;

     retain _chk 0;

     set a;

     by COD;

     if first.cod then do; _flag = flag; chk=0; end;

     else if _flag ne flag

               then do;

               _flag=flag;

               chk = 1;

           end;

run;

it works but i don't get the table that I need.

how can I do that?

[stat_sas · Accepted solution]

proc sql;

create table want as

select *,case when count(distinct flag)>1 then 1 else 0 end as chk

from mytable

group by cod;

quit;

[Ksharp]

data have;
input COD  FLAG     $;
cards;
1          N
1          N
1          S
2          N
2          N
3          S
3          N
;
run;
proc sql;
create table want as
 select *,case when count(distinct flag) gt 1 then 1 else 0 end as chk
  from have
   group by cod;
quit;
 

Xia Keshan

[Rakeon]

Thank you,

all of you!!!

Thanks!