/*generate random number from uniform distribution*/
/*for use in splitting the sample*/
data dataname2;/*new data with one extra column with name 'random'*/
set dataname1; /input data with name dataname1*/
/*generate a random order for each observation*/
/*8329 can be replaced by any number*/
seed=8329;
random=ranuni(seed);
run;


/*split dataname2 into two datasets sample1 and sample2*/
/*in this example code, first 300 in sample1 and the rest in sample2*/

proc sort data=dataname2; by random; run;
data dataname2 sample1 sample2;
set dataname2;
if _n_<301 then do;
  sample=1;
  output sample1;
  y1=y; /*y is the outcome(dependent) variable*/
  end;
  else do;
  sample=2;
  output sample2;
  y2=y;/*y is the outcome(dependent) variable*/
  end;
  output dataname2;
  run;