So you want to have a parallel linear? solver and the rest of the code
including Jacobian generation sequential?
Barry
> On Apr 12, 2018, at 2:32 PM, Klaus Burkart wrote:
>
> Are your matrix entries stored in parallel or is your current code that
> generates the rows, columns, and values sequential.
>
> >> The three arrays are the result of a matrix format conversion to CSR
> >> format in my cfd application interface, the code is sequential.
>
>
> Does your matrix have a pointwise-block structure (like from having
> multiple degrees of freedom per grid point) or is it a scalar PDE? If scalar
> than you use AIJ matrices if point wise-block structure then use BAIJ. If
> symmetric than use SBAIJ.
>
> >> I assume it's a case for AIJ
>
>
> How are your matrix entries generated? Via the finite element method, finite
> differences, something else? Is there a mesh, how do you handle the mesh?
>
> >> Via finite volume, yes there is a mesh but I am only replacing the matrix
> >> solver (as I've done with another LA library before) afterwards returning
> >> the solution vector to the application where all the other steps are
> >> handled
>
> Klaus
>
>
> Am Donnerstag, 12. April 2018, 21:10:12 MESZ hat Smith, Barry F.
> Folgendes geschrieben:
>
>
>
> Are your matrix entries stored in parallel or is your current code that
> generates the rows, columns, and values sequential.
>
> Does your matrix have a pointwise-block structure (like from having
> multiple degrees of freedom per grid point) or is it a scalar PDE? If scalar
> than you use AIJ matrices if point wise-block structure then use BAIJ. If
> symmetric than use SBAIJ.
>
> How are your matrix entries generated? Via the finite element method,
> finite differences, something else? Is there a mesh, how do you handle the
> mesh?
>
> Barry
>
>
> > On Apr 12, 2018, at 1:54 PM, Klaus Burkart wrote:
> >
> > I am confused with matrix object types and which one to use in my case:
> >
> >
> > I want to solve a linear system using multiple processes. The steps I am
> > struggling with is the import of the global matrix and global rhs vector
> > into applicable PETSc objects.
> >
> > The global matrix is currently stored in CSR format using 3 arrays. Array
> > one contains all the row indices, array two all the column indices, array
> > three all the values of the global matrix. In addition to that, there's a
> > vector object containing the rhs vector.
> >
> > I think for the vector object I should use VectorCreateMPI with m set to
> > PETSC_DECIDE?
> >
> >
> > What's the matrix object I should use in my case which also takes care of
> > the allocation local matrices to the processes at a later stage i.e.
> > creates the local matrices in line with the rhs vector?
> >
> > Klaus
