On Wed, 16 Apr 2008, Tim Kroeger wrote: > Next question from me: Is there some easy way in libMesh to compare > computation results on different grids? I.e., I have two > EquationSystems instances that consist of equal systems but live on > different grids, where both grids are refinements of the same initial > grid. For each variable in each system, I want the difference of the > computed solutions on the two grids, in various norms (say L1, L2, > Linfty). > > I conjecture that there is no easy way to do this in libMesh, but I > thought it might be sensible to ask.
If by "different" you mean that one mesh is everywhere as fine as or finer than the other, then you can construct a MeshFunction from the coarser solution and use it with an ExactSolution object on the fine system to get the right answer. If one grid is finer in some places and the other grid is finer in others then there's currently no way to do this precisely. You might use the ExactSolution trick on a "mostly finer" grid with an overkill quadrature rule to get something close enough, but the right thing to do here would require new code. It's a common problem, though; if you write the aforementioned new code please consider contributing it to the library. ;-) --- Roy ------------------------------------------------------------------------- This SF.net email is sponsored by the 2008 JavaOne(SM) Conference Don't miss this year's exciting event. There's still time to save $100. Use priority code J8TL2D2. http://ad.doubleclick.net/clk;198757673;13503038;p?http://java.sun.com/javaone _______________________________________________ Libmesh-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/libmesh-users
