topic Re: interleaving 2 datasets with SET statement in SAS Programming

interleaving 2 datasets with SET statement

Jaheuk — Thu, 24 Feb 2011 10:56:29 GMT

why does my final output dataset has only 2 rows and not 6 (for each date a prod line)?

data dates;
input date $ ;
cards;
01/02/2010
02/02/2010
03/02/2010
;
run;
data prods;
input prod $ ;
cards;
PRODA
PRODB
;
run;

data prods_dates;
set dates;
do order=1 to LAST;
set prods nobs=LAST;
output;
end;
RUN;

Re: interleaving 2 datasets with SET statement

deleted_user — Thu, 24 Feb 2011 11:26:32 GMT

hello,

your final output has only 2 rows because SAS reads sequentially which determines the end of prods file to be "achieved" on the first pass to the data step.

you expected on the second pass to the data step that SAS reads the prods file from the beginning, but instead SAS stops execution and this is because SAS reached the end of prods file.

one solution is using direct access to read the prods file:

[pre]
data prods_dates;
set dates;
i=1;
do order=1 to LAST;
set prods point=i nobs=LAST ;
output;
i+1;
end;
RUN;
[/pre]

Marius

Re: interleaving 2 datasets with SET statement

sbb — Thu, 24 Feb 2011 12:27:58 GMT

The SAS variable LAST is incremented until it reaches the NOBS= value (based on WORK.PRODS). Then, unless you were to reset the value to LAST=0; outside your DO /END loop, the "expression" condition will never be met again.

For self-diagnosis, suggest you add the following statement at various points in your SAS program to display all SAS variable values:

PUTLOG '>DIAG>' / _ALL_;

Scott Barry
SBBWorks, Inc.

Re: interleaving 2 datasets with SET statement

Jaheuk — Thu, 24 Feb 2011 15:35:10 GMT

Marius, thx for solution and reason why it did not work 😉

CU,
Herman