On Tue, Feb 16, 2016 at 9:51 AM, Harshad Sahasrabudhe <hsaha...@purdue.edu> wrote:
> Hi, > > I'm using QTrap to integrate a differential equation for a generalized > eigenvalue problem. I'm using CondensedEigenSystem to solve the equation. > When I use QTrap, I get a diagonal B matrix in > > A \psi = \lambda B \psi > > So my question is: Is the sparsity pattern of B set according to the > quadrature rule or is it the same as A? A and B share the same sparsity pattern, which is determined by the element connectivity and FE types involved, but not quadrature rules. > I'm using KrylovSchur eigensolver > in SLEPc and I find that the eigenvalue computation anti-scales when I use > anti-scales? > Gauss quadrature. Having a diagonal pattern in B might fix the scaling and > increase the performance. > > Do you have any other suggestions on improving the scaling? > Use preconditioners which scale well, like AMG, if they make sense for your problem. -- John ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 _______________________________________________ Libmesh-users mailing list Libmesh-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libmesh-users
