Arrays

[robertrao]

Hi

the variables in and out are created newly based on some condition..

why do we have to set these to missing  in=.; out=.;

Doesn't sas do that automatically?????

Thanks

[jwsquillace · Accepted solution]

SAS sets DATA step variables to missing between iterations of the DATA step.

Your code indicates that you want them set to missing for each iteration of the DO loop, that you must do with assignment statements as you have done.

Here is more information on the details of DATA step execution:

SAS(R) 9.3 Language Reference: Concepts, Second Edition

Processing a DATA Step: A Walk-through

Jan