proc transpose data = c01(keep = id var3) out = var3 prefix = var3;
by id notsorted;
var var3;
run;
proc transpose data = c01(keep = id var7) out = var7 prefix = var7;
by id notsorted;
var var7;
run;
.....
data all;
merge var3 var7 ----var21;
run;
结果应该是
id var31 var32......var3** var71 var72 var7**.......