data SAMPLE(drop = i j count);
count = 0;
array sel_obs(100) _temporary_;
do i = 1 to 100;
redo: select = ceil(ranuni(0)*total);
do j = 1 to count;
if sel_obs(j) = select then goto redo;
end;
set POP point=select nobs=total;
count = count + 1;
sel_obs(count) = select;
output;
end;
stop;
run;