Thanks for your instant and helpful answer. So, the grid from other mesh
generator cannot be made coarser at all. As I referred from step-5
tutorial, I guess a procedure like associating the surface boundaries (from
meshing software) to the manifolds would also only works for meshing
refinement
Dear Truong,
My understanding is that the triangulation in deal.II works like a
quad/oct-forest.That is, the mesh that is generated or read serves as the
forest and each cell is a tree. Consequently, it is not possible to coarsen
a mesh more than it's initial configuration.
For a lot of meshes
