Hey FreeFem team, I recently debugged my code and found that, with a mesh generated by gmsh, the results from the direct solver and iteration solver under ffddm are totally different; I believe this problem is coming from the mesh, since I test it with other meshes build from freefem directly; My q…

Are you solving an elasticity problem? BJacobi + ILU as subdomain solver is probably the worst kind of preconditioner for this problem. You can use optimal multigrid methods, see the 2D or 3D parameters. If this still does not converge well, could you share your script?

Iteration solver and direct solver results are huge different with some meshes

General Discussion

zcwang6 (Zcwang6) February 11, 2021, 8:09pm 14

Sure, I will test it. Thx;

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Iteration solver and direct solver results are huge different with some meshes

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