the following is about MatMult() in manual. " The parallel matrix can multiply a vector with n local entries, returning a vector with m local entries. That is, to form the product MatMult(Mat A,Vec x,Vec y); the vectors x and y should be generated with VecCreateMPI(MPI Comm comm,n,N,&x); VecCreateMPI(MPI Comm comm,m,M,&y); " I am wondering whether I must create Vector "y" before I call MatMult() regardless of parrellel and sequentail modes? thanks a lot.
Regards, Yujie -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-users/attachments/20080422/51f11ff5/attachment.htm>
