proc iml;

   /*------------------------------------------------------*/
   /*               The CHOOSE Module                      */
   /*                                                      */
   /* We consider all the possible choices of M objects    */
   /* from a set of M+N. There is a sequential way of      */
   /* ordering them. The module CHOOSE gives you the next  */
   /* choice when you supply a given selection and the     */
   /* parameters M and N. The vector VEC is input and      */
   /* consists of integers from 1 to M+N. Examples if you  */
   /* are choosing five objects from a set of 8:           */
   /* 1) Input mvec0=[1 2 3 5 7] and get mvec1=[1 2 3 5 8] */
   /* 2) Input mvec0=[1 3 4 7 8] and get mvec1=[1 3 5 6 7] */
   /* This module is used inside the module PERMTEST.      */
   /*------------------------------------------------------*/

start choose(vec,mvec0,m,n, mvec1);
mvec1=mvec0;
do place=m to 1 by -1;
   if mvec0[1,place](mn+1)/2);
   if test='VW' then score0=probit(mvec0/(mn+1));
   if test='SAVAGE' then do;
      score0=j(1,m,.);
      do j = 1 to m;
         mj=mvec0[1,j];
         score0[1,j]=sum(savvec[1,1:mj])-1;
      end;
   end;
   rankstat=sum(score0);
   if rankstat<=sumscore then pval[1,1]=pval[1,1]+1;
   if rankstat>=sumscore then pval[1,2]=pval[1,2]+1;
   pval[1,3]=2*min(pval[1,1],pval[1,2]);
   if i1 then pval[1,3]=1;
reset noname;
chead={"Lower-Tail" "Upper-Tail" "Two-Tail"};
print pval[colname=chead];
finish;