<div class="gmail_quote">On Thu, Dec 29, 2011 at 01:27, Rahul Praghanmor <span dir="ltr"><<a href="mailto:praghanmor@gmail.com">praghanmor@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div id=":db">I successfully implement PETSc to solve on a single zone unstructured mesh i.e. serial implementation has done and tested.<br>Now I want to implement a PETSc on a multi-zone mesh.The mesh partitioning in multi-zone is done using a separate tool, Metis. The multi-zone mesh is read in solver.I don't understand how to do the global indexing for multi-zone mesh to form a global matrix required for PETSc.</div>
</blockquote></div><br><div>Start with a non-overlapping partition (usually what is provided by Metis). Distribute the mesh according to this partition, then compute the local size and use MPI_Scan() to compute the offset of your piece in the global ordering. You can learn the global index of ghosted points by sending it from owner to ghoster through the overlap.</div>