Date:         Sun, 9 Jul 2006 20:12:34 -0400
Reply-To:     "Howard Schreier <hs AT dc-sug DOT org>" <nospam@HOWLES.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         "Howard Schreier <hs AT dc-sug DOT org>" <nospam@HOWLES.COM>
Subject:      Re: Combine data sets

On Sun, 9 Jul 2006 15:46:21 -0700, Li Zhang <zhanglitt@YAHOO.COM> wrote:

>I have 100 data sets, namely temp_1 .. temp_100, all
>of which have the same variables that are in the same
>order. I'd like to combine them together to form a
>single data set.
>
>I wrote a tiny Macro which looks ugly, is there any
>better way to do it?
>
>Thank you
>
>
>
>%Macro Combine;
>data M;
>set temp_1;
>run;
>
>%do i = 2 %to 100;
>data M;
>set  M temp_&i.;
>run;
>%end;
>%Mend;
>
>%Combine;

What's ugly is the log, because there will be 100 DATA steps, where only one
is needed.

It's also inefficient, as the observations in TEMP_1 will be passed 99 times
more than necessary, those in TEMP_2 98 times more, etc.

Try

   %Macro Combine;
                           data M;
                           set
   %do i = 1 %to 100;
                           temp_&i.
      %end;
                           ;
                           run;
   %Mend;

   %Combine