On Mon, Feb 20, 2012 at 20:09, recrusader <recrusader@gmail.com> wrote:

I am taking a look at ex15 (http://www.mcs.anl.gov/petsc/petsc-current/src/mat/examples/tutorials/ex15.c.html).
I am very confused with this. In Section 3.5 Partitioning of the manual, one special Mat, that is 'adj', need to be established.
However, in ex15, the common matrix is created. Does the matrix automatically contain the connection information?

Most (perhaps all?) of the partitioning implementations work with normal AIJ matrices. Internally, they usually have to convert to the MPIAdj because that is the interface to ParMETIS and others. Your code doesn't have to think about it.