Re: [deal.II] PETScWrappers::SparseDirectMUMPS use in parallel version of step-22

Dear Timo, Thank you for your reply. I am still having trouble with implementing my code with MUMPS. I will briefly describe the problem: I am solving 2 systems of Maxwell's equations in the following way: the systems are Ax1=b1 and Ax2=b2; A is a sparse block symmetric matrix (C -M; -M

Re: [deal.II] PETScWrappers::SparseDirectMUMPS use in parallel version of step-22

Dear Timo, Thank you for your reply. I am still having trouble with implementing my code with MUMPS. I will briefly describe the problem: I am solving 2 systems of Maxwell's equations in the following way: the systems are Ax1=b1 and Ax2=b2; A is a sparse block symmetric matrix (C -M; -M

Re: [deal.II] PETScWrappers::SparseDirectMUMPS use in parallel version of step-22

Dear Timo, Because I do not understand how to reuse this decomposition in deal.ii. I am relatively new to deal.ii and C++, and I have never used mumps before. I would appreciate any advice on this. Maybe there is some example in deal.ii that use mumps to construct a preconditioner. Thank you

[deal.II] EigenValue Problem

Jean-Paul is right. Most likely you don't adjust the quadrature order which breaks LU factorization of the mass matrix, used by default for Generalized Hermitian Eigenvalue Problem. Essentially your mass matrix is not positive definite anymore. Regards, Denis -- The deal.II project is

Re: [deal.II] EigenValue Problem

Dear Nitish, I’m not familiar with this tutorial and I don’t have much to suggest, but I have one basic question: When increasing the polynomial order of the finite element, do you increase the corresponding quadrature order as well? Regards, Jean-Paul > On 19 Sep 2017, at 14:53, Nitish Anand

[deal.II] EigenValue Problem

Hey, I wish to solve an eigenvalue problem for a rotating disk and to understand more about the implementation I looked into the step-36 example. Unfortunately, when I increase the degrees of freedom in the code (changing line 70 to fe(3) or fe(2)) I get the following error. Number of

Re: [deal.II] Refining a cylinder only in x

Dear Lucas, you could use GridTools::remove_anisotropy Best, Luca. > On 18 Sep 2017, at 16:29, Lucas Campos wrote: > > Dear Bruno, > > You will find attached the resulting grids. While I originally expected to > find new divisions only along the x-direction, your

Re: [deal.II] PETScWrappers::SparseDirectMUMPS use in parallel version of step-22

> template > void Pa_Preconditioner:: > vmult(LA::MPI::BlockVector , const LA::MPI::BlockVector ) const > { > SolverControl cn; > PetScWrappers::SparseDirectMUMPS solver(cn,mpi_communicator); > solver.set_symmetric_mode(true); > solver.solve(B,dst.block(0),src.block(0)); >

Re: [deal.II] Refining a cylinder only in x

If you are just interested in a cylinder with more than a single layer, it might be easier to make k copies of the cylinder, shift them, and use merge_triangulations() to combine them into a single mesh. On Tue, Sep 19, 2017 at 5:00 AM, luca.heltai wrote: > Dear Lucas, > >

Re: [deal.II] Refining a cylinder only in x

Oh, even easier would be creating a 2d cylinder and then using GridGenerator::extrude_triangulation() On Tue, Sep 19, 2017 at 1:47 PM, Timo Heister wrote: > If you are just interested in a cylinder with more than a single > layer, it might be easier to make k copies of the

[deal.II] deal.II Newsletter #5

Hello everyone! This is deal.II newsletter #5. It automatically reports recently merged features and discussions about the deal.II finite element library. ## Below you find a list of recently proposed or merged features: #5113: Remove unused private function DoFHandler::reserve_space