关于计划外访视编号的程序

 set sv4;
 by _usubjid;
 retain visit_r 0;
 if first._usubjid then visit_r=visitnum1;

 if missing(visitnum1) then visitnum1=visit_r+0.01;
 visit_r=visitnum1;
run;
data sv6;
     set sv5;
 by _usubjid;
 retain ttt;
 if first._usubjid then ttt=visit1;

 if missing(visit1) then visit1=ttt;
 ttt=visit1;
run;