You need to indicate that the DA is periodic when you create it.

  Matt

On Tue, Nov 30, 2010 at 4:32 PM, khalid ashraf <khalid_eee@yahoo.com> wrote:
Thanks Barry. It works fine. Another question, I have a Periodic Boundary
condition along x and y. So I want to use the two commented out line below.
   for (j=ys; j<ys+ym; j++) {
   for (i=xs; i<xs+xm; i++) {
     if (i<(mx-1))
     {
     Cx=u_localptr[k][j][i+1]-u_localptr[k][j][i];
     }
 else
     {
//     Cx=u_localptr[k][j][i]-u_localptr[k][j][0];
     }
     if (j<(my-1))
     {
     Cy=v_localptr[k][j+1][i]-v_localptr[k][j][i];
     }
 else
     {
 //    Cy=v_localptr[k][j][i]-v_localptr[k][0][i];
     }

Is it possible to include these non-local points [k][j][0] or [k][0][i]. Or I have to 
include the boundary points in the grid ? The same question when forming the A matrix with 
PBC. How to include the non-neighbour elements within the if statement. 

Thanks.

Khalid




--
What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.
-- Norbert Wiener