code help- how to seperate subjects with multiple occurances that satisfy a certain condition

robertrao — Mon, 24 Sep 2012 15:20:55 GMT

Hi All,

Could some on ehelp me in understanding the code for the question with the title shown above.

Detail codes are given for that question and could some on explain to me why the same dataset is set twice and whats the logic behind...etc etc

Thanks

Re: code help- how to seperate subjects with multiple occurances that satisfy a certain condition

ballardw — Mon, 24 Sep 2012 17:57:40 GMT

Time to provide an example of input data and desired output as the topic is very vague.

Re: code help- how to seperate subjects with multiple occurances that satisfy a certain condition

robertrao — Mon, 24 Sep 2012 18:27:40 GMT

Dear Ballard,

Thanks for the help.

Below is the data I am referring to:

The output I desired is below the data;

This question has been answered (several codes seen below) earlier in the forum......BUT since I am a beginner i want the explanation of the code

Several ways of code are given below (bottom of this reply)

/*Classic 2X DOW*/

/*Merge*/

/*Hash()*/

Only the merge method I am familiar

Even in that method there are 2 times we set the same dataset......explanation for stuff like this...........

In this data set, I need to separate the records where Arrears_Band at least once has “writoff” value.

data have;

informat Current_date date9.;

Input Current_date Account_number 11-13 Arrears_Band $ 15-25;

Format Current_date date9.;

cards;

31MAY2011 111 NPNA

30JUN2011 111 writoff

31JUL2011 111 NPNA

31AUG2011 111 NPNA

30SEP2011 111 NPNA

31OCT2011 111 NPNA

30NOV2011 111 NPNA

31DEC2011 111 NPNA

31JAN2012 111 NPNA

31DEC2011 222 NPNA

31JAN2012 222 NPNA

30NOV2010 333 NPNA

31DEC2010 333 NPNA

31JAN2011 333 NPNA

28FEB2011 333 NPNA

31MAR2011 333 writoff

30APR2011 333 NPNA

31MAY2011 333 NPNA

30JUN2011 333 NPNA

31JUL2011 333 NPNA

31AUG2011 333 NPNA

30SEP2011 333 NPNA

31OCT2011 333 NPNA

30NOV2011 333 NPNA

31DEC2011 333 NPNA

31JAN2012 333 NPNA

28FEB2010 444 Current

31MAR2010 444 30 - 60

30APR2010 444 30 - 60

31MAY2010 444 Current

30JUN2010 444 Current

31JUL2010 444 Current

31AUG2010 444 Current

30SEP2010 444 Current

31OCT2010 444 Current

30NOV2010 444 Current

31DEC2010 444 Current

31JAN2011 444 1 - 30

28FEB2011 444 30 - 60

31MAR2011 444 60 - 90

30APR2011 444 90 +

31MAY2011 444 90 +

30JUN2011 444 90 +

31JUL2011 444 NPNA

31AUG2011 444 NPNA

30SEP2011 444 NPNA

31OCT2011 444 NPNA

30NOV2011 444 NPNA

31DEC2011 444 NPNA

31JAN2012 444 NPNA

28FEB2010 555 30 - 60

31MAR2010 555 30 - 60

30APR2010 555 60 - 90

31MAY2010 555 NPNA

31JAN2012 666 writoff

31JAN2012 777 NPNA

;

run;

/*Answer*/

The data set I want is this.

Current_date Account_number Arrears_Band

31MAY2011 111 NPNA

30JUN2011 111 writoff

31JUL2011 111 NPNA

31AUG2011 111 NPNA

30SEP2011 111 NPNA

31OCT2011 111 NPNA

30NOV2011 111 NPNA

31DEC2011 111 NPNA

31JAN2012 111 NPNA

30NOV2010 333 NPNA

31DEC2010 333 NPNA

31JAN2011 333 NPNA

28FEB2011 333 NPNA

31MAR2011 333 writoff

30APR2011 333 NPNA

31MAY2011 333 NPNA

30JUN2011 333 NPNA

31JUL2011 333 NPNA

31AUG2011 333 NPNA

30SEP2011 333 NPNA

31OCT2011 333 NPNA

30NOV2011 333 NPNA

31DEC2011 333 NPNA

31JAN2012 333 NPNA

31JAN2012 666 writoff

/*Classic 2X DOW*/

data want;

do until (last.account_number);

set have;

by account_number;

if Arrears_Band='writoff' then flag+1;

end;

do until (last.account_number);

set have;

by account_number;

if flag >=1 then output;

end;

call missing(flag);

drop flag;

run;

/*Merge*/

data want;

merge have (where=(Arrears_Band='writoff') in=a) have (in=b);

by account_number;

if a and b;

run;

/*Hash()*/

data want;

if _n_=1 then do;

if 0 then set have;

dcl hash h(dataset:'have', multidata:'y');

h.definekey('account_number');

h.definedata(all:'y');

h.definedone();

end;

do until (last.account_number);

set have;

by account_number;

if Arrears_Band='writoff' then flag+1;

end;

if flag>=1 then do;

rc=h.find();

do rc=0 by 0 while (rc=0);

output;

rc=h.find_next();

end;

call missing(flag);

drop flag rc;

run;

Re: code help- how to seperate subjects with multiple occurances that satisfy a certain condition

art297 — Tue, 25 Sep 2012 19:48:47 GMT

Karun,

I presume you are asking why/how the DOW works.

It is simply you taking control of the data step. Your code has two loops (i.e., do until statements), each set(ing) the file 'have' with a by statement.

Each Account_number goes through the two loops separately. Thus, in the first loop, it looks through all of the records that have Account_number 111 and, for each of those that contain an Arrears_Band equal to "write off", it increments a variable called flag. If the Account_number has one such record, flag will be set to 1, if it has two it will be set to 2, etc.

Then, in the second loop, it again looks only at the Account_number 111 records, but the value of the flag variable is present in each of the records. If it is greater than one, then the records are output;

Finally, flag is set to missing, and then dropped from the output file, and the system goes back to the first loop and reads account number 222, and so on, and so on.

topic code help- how to seperate subjects with multiple occurances that satisfy a certain condition in SAS Procedures

code help- how to seperate subjects with multiple occurances that satisfy a certain condition

Re: code help- how to seperate subjects with multiple occurances that satisfy a certain condition

Re: code help- how to seperate subjects with multiple occurances that satisfy a certain condition

Re: code help- how to seperate subjects with multiple occurances that satisfy a certain condition