Re: [Libmesh-users] GMSH read - bad EDGE2 elemtype for second order approximation

[John P. <jwp...@gm...>]

On Thu, Nov 16, 2017 at 5:08 PM, Renato Poli <re...@gm...> wrote:

> Hi
>
> I generated a square mesh in GMSH and exported to read into libMesh.
>
> I use second order approximation for variables.
>
> After reading, libMesh is exiting with the following error:
>
>
> ERROR: Bad ElemType = EDGE2 for SECOND order approximation!
> Stack frames: 14
> 0: libMesh::print_trace(std::ostream&)
> 1: libMesh::MacroFunctions::report_error(char const*, int, char
> const*, char const*)
> 2: /usr/local/lib/libmesh_opt.so.0(+0x4c8cfb) [0x7fa7cc123cfb]
> 3: libMesh::FEInterface::n_dofs_at_node(unsigned int, libMesh::FEType
> const&, libMesh::ElemType, unsigned int)
> 4: libMesh::DofMap::reinit(libMesh::MeshBase&)
> 5: libMesh::DofMap::distribute_dofs(libMesh::MeshBase&)
> 6: libMesh::System::init_data()
> 7: libMesh::ImplicitSystem::init_data()
> 8: libMesh::LinearImplicitSystem::init_data()
> 9: libMesh::System::init()
> 10: libMesh::EquationSystems::init()
> 11: obj/bin/abada_sc4() [0x57c0ed]
> 12: __libc_start_main
> 13: obj/bin/abada_sc4() [0x4322f9]
> [0] src/fe/fe_lagrange.C, line 642, compiled Aug 14 2017 at 15:16:26
> application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
> [unset]: write_line error; fd=-1 buf=:cmd=abort exitcode=1
> :
> system msg for write_line failure : Bad file descriptor
>
>
> My GMSH mesh looks good - I have added boundary conditions, my msh
> file has PhysicalNames etc.
>
> Everything looks nice.
>
> Any idea on what might be wrong?
>
> This is my ".geo" file if anyone wants to enjoy a gmsh adventure...
>
> cl__1 = 1;
> Point(1) = {0, 0, 0, 1};
> Point(2) = {0, 100, 0, 1};
> Point(3) = {100, 100, 0, 1};
> Point(4) = {100, 0, 0, 1};
> Line(1) = {1, 2};
> Line(2) = {2, 3};
> Line(3) = {3, 4};
> Line(4) = {4, 1};
> Line Loop(6) = {1, 2, 3, 4};
> Plane Surface(7) = {6};
> Physical Line("ext") = {1, 2, 3, 4};
>

I think you need to run gmsh with a special option (maybe "-2") to make
sure that you get EDGE3 elements. Those are required for using SECOND,
LAGRANGE finite elements.

-- 
John