Variables in order ("retain")

[Ken_oy]

I use "retain" to make variables in order.

But I don't know how to do the following:

I have a SAS dataset like:

A1 A2 A3 ... A300  B1 B2 B3 ... B300  C1 C2 C3 ... C300;

I want to make it in the following order;

A1 B1 C1 A2 B2 C2 A3 B3 C3 ... A300 B300 C300;

How?

Thanks

[Linlin · Accepted solution]

untested code:

%macro test;

data want;

  retain  %do i=1 %to 300;

    a&i b&i c&i

%end;;

set have;

run;

%mend;

%test

[Ken_oy]

@Linlin

Thanks, your code works perfectly!