call MatCreateMPIAIJ(PETSC_COMM_WORLD, Np, Np, Ng, Ng, &
nmax, PETSC_NULL_INTEGER, nmax, PETSC_NULL_INTEGER, Jac, info)well, now I get: [1]PETSC ERROR: --------------------- Error Message ------------------------------------ [1]PETSC ERROR: Null argument, when expecting valid pointer! [1]PETSC ERROR: Null Object: Parameter # 2! how can I create the matrix without d_nnz and o_nnz?
