Create data set. REFLIB.NUMS uses a set of randomly sampled points to create the data used in this and all remaining examples in this chapter.
data reflib.nums;
   keep x y z;
   do i=1 to 30;
      x=10*ranuni(33)-5;
      y=10*ranuni(35)-5;
      z=sin(sqrt(x*x+y*y));
      output;
   end;
run;