Hi Daniel, It works with a direct solver. It is working with the CG solver as well I just increased the number of iterations (1000-> 2000) and decreased the tolerance (10^ -12 -> 10 ^ -10)
Note about the system I am solving: In my PDE my RHS =0 (homogenous Helmholtz Eq. with Dirichlet BC) , Basically I am solving a system Ax=0 If there is a better way to solve this I would like to try. Edith > On Oct 9, 2016, at 3:33 AM, Daniel Arndt <[email protected]> > wrote: > > Edith, > > If I understand you correctly, you basically consider step-7 and replace the > Neumann boundary conditions by inhomogeneous Dirichlet boundary conditions. > The system matrix is symmetric and positive definite and hence CG should work. > > Can you verify that the solution is correct if you use a direct solver > (SparseDirectUMFPACK [1])? > > Best, > Daniel > > [1] https://www.dealii.org/8.4.1/doxygen/deal.II/classSparseDirectUMFPACK.html > > -- > The deal.II project is located at http://www.dealii.org/ > <http://www.dealii.org/> > For mailing list/forum options, see > https://groups.google.com/d/forum/dealii?hl=en > <https://groups.google.com/d/forum/dealii?hl=en> > --- > You received this message because you are subscribed to a topic in the Google > Groups "deal.II User Group" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/dealii/F6_iqj1mJnA/unsubscribe > <https://groups.google.com/d/topic/dealii/F6_iqj1mJnA/unsubscribe>. > To unsubscribe from this group and all its topics, send an email to > [email protected] > <mailto:[email protected]>. > For more options, visit https://groups.google.com/d/optout > <https://groups.google.com/d/optout>. -- The deal.II project is located at http://www.dealii.org/ For mailing list/forum options, see https://groups.google.com/d/forum/dealii?hl=en --- You received this message because you are subscribed to the Google Groups "deal.II User Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
