SAS - Combinations - Using LEXCOMBI to generate unique combination lists

sas_unique_combinations.sas

/*this creates a list of combinations, designed for numeric variables*/

%let n=5;              /* total number of items */          
%let k=2;              /* number of items per row */
/* generate combinations of n items taken k at a time */
data Comb(keep=c1-c&k);
array c[&k] (&k.*0);   /* initialize array to 0 */
array list[&n] _temporary_ (1, 2, 3, 4, 5);
ncomb = comb(&n, &k);  /* number of combinations */
do j = 1 to ncomb;
   rc = lexcombi(&n, &k, of c[*]);
   
   do i=1 to dim(c);
        c(i)=list(c(i));
   end;
   output;
end;
run;