1      integer function argos_space_btop(ibox,ibownr)
2c
3      implicit none
4c
5#include "argos_space_common.fh"
6c
7      integer ibox,ibownr(maxbox,3)
8      integer iboxx,iboxy,iboxz
9c
10      iboxx=mod(ibox,nbx)
11      iboxy=mod((ibox-iboxx)/nbx,nby)
12      iboxz=((ibox-iboxx)/nbx-iboxy)/nby
13      argos_space_btop=(ibownr(iboxz+1,3)*npy+ibownr(iboxy+1,2))*npx+
14     + ibownr(iboxx+1,1)
15c
16      return
17      end
18c $Id$
19