* ===================================================================================================== ;
* Row data file;
%let yfile=F:\drr2k\ed351\megdata.dat;

* corresponding array of time observations ;
%let tfile=F:\drr2k\ed351\megtdata.dat;

* Output Datum data file;
%let Indfile=F:\drr2k\ed351\megdatadatum.dat;

* Largest number of entries for any individual in time array;
%let tn=5;

* Exogenous variable indicator ;
%let w=0;

%macro row2ind;

  %if &w=0 %then
   %do;
    data Y;
     infile "&yfile";
     input id y1-y&tn;
    run;
   %end;

  %if &w^=0 %then
   %do;
    data Y;
     infile "&yfile";
     input id y1-y&tn w;
    run;
   %end;

  data T;
   infile "&tfile";
   input id t1-t&tn;
  run;

  proc sort data=Y;
   by id;
  run;

  proc sort data=T;
   by id;
  run;


  data yt_mixed;
   merge Y T;
    by id;
  run;

  data yt;
    set Yt_mixed;
    attrib _numeric_ length=8;
    array yy{&tn} y1-y&tn;
    array tt{&tn} t1-t&tn;
    case = _n_;
    do i = 1 to &tn;
     attrib y time length=8;
     time = tt{i};
     y  = yy{i}; 
     output;
    end;
  %if &w=0 %then
   %do;
    keep id y time;
   %end;
  %if &w=1 %then
   %do;
    keep id y time w;
   %end;
  run;

 data _null_;
  set yt;
  file "&IndFile";
  %if &w=0 %then
   %do;
    put id y time;
   %end;
  %if &w=1 %then
   %do;
    put id y time w;
   %end;
 run;

%mend row2ind;
%row2ind;