On Feb 4, 2008 12:20 PM, Yujie <recrusader at gmail.com> wrote: > what is the difference between sequantial and parallel AIJ matrix? Assuming > there is a matrix A, if I partitaion this matrix into A1, A2, Ai... An. > A is a parallel AIJ matrix at the whole view, Ai is a sequential AIJ matrix?
We mean parallel CSR format, which is described in the book Iterative Methods for Sparse Linear Systems by Yousef Saad as well as in the PETSc manual. > I want to operate Ai at each node. > In addition, whether is it possible to get general inverse using > MatMatSolve() if the matrix is not square? Thanks a lot. Rectangular matrices do not have inverses in that sense. You may want some sort of pseudo-inverse, but it must be motivated by the problem you are solving. Matt > Regards, > Yujie > > > On 2/4/08, Barry Smith <bsmith at mcs.anl.gov> wrote: > > > > For sequential AIJ matrices you can fill the B matrix with the > > identity and then use > > MatMatSolve(). > > > > Note since the inverse of a sparse matrix is dense the B matrix is > > a SeqDense matrix. > > > > Barry > > > > On Feb 4, 2008, at 12:37 AM, Yujie wrote: > > > > > Hi, > > > Now, I want to inverse a sparse matrix. I have browsed the manual, > > > however, I can't find some information. could you give me some advice? > > > > > > thanks a lot. > > > > > > Regards, > > > Yujie > > > > > > > > > -- 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
