How to get the median and other quantiles of data in the same row of several vectors?

[ShufeGuoding]

How to get the median and other quantiles of data in the same row of several vectors using IML functions?

[Rick_SAS]

Look at the QNTL subroutine. The QNTL function operates on columns of a matrix, so if you have several vectors you can concatenate them together (use the || operator)  and compute all the quantiles at once.

[ShufeGuoding]

How to do it using SAS 9.2IML? Thanks!

[IanWakeling]

You could adapt my code here which uses the SAS pctl function:

http://listserv.uga.edu/cgi-bin/wa?A2=ind0812A&L=sas-l&D=0&P=35674

But this is not a workable solution unless your matrices will always be small.  As Dale said in the same thread:

http://listserv.uga.edu/cgi-bin/wa?A2=ind0812A&L=sas-l&D=0&P=37690

you will probably be better off building your own percentile function.

[Rick_SAS]

   proc iml;

   start myQntl(q, x, p);         /* definition 5 from UNIVARIATE doc */

      y = colvec(x);

      call sort(y,1);

      n = nrow(y);                   /* assume nonmissing data */

      q = j(ncol(p),1);

      do i = 1 to ncol(p);

         j  = (n+1)*p;            /* position in ordered data */

         j1 = floor(j); j2 = ceil(j);/* indices into ordered data */

         print j j1 j2;

         if j1=j2 then               /* return a datum */

            q = y[j1];

         else                        /* interpolate between data */

            q = (y[j2]+y[j1])/2;

      end;

   finish;

   /* test it */

   x = ranuni(j(100,1));

   p = {0.1 0.25 0.5 0.75 0.9};

   call MyQntl(q, x, p);

   print q;