wahl@fma82 Fitted_Multigrid: python3 StokesMultigrid.py 
importing NGSolve-6.2.1908-78-g7e9b46d6
 Generate Mesh from spline geometry
 Boundary mesh done, np = 12
 CalcLocalH: 12 Points 0 Elements 0 Surface Elements
 Meshing domain 1 / 1
 load internal triangle rules
 Surface meshing done
 Edgeswapping, topological
 Smoothing
 Split improve
 Combine improve
 Smoothing
 Edgeswapping, metric
 Smoothing
 Split improve
 Combine improve
 Smoothing
 Edgeswapping, metric
 Smoothing
 Split improve
 Combine improve
 Smoothing
 Update mesh topology
 Update clusters
assemble VOL element 24/24                                 
call umfpack ... done
assemble VOL element 24/24                                 
setvalues element 12/12                                 
Step 1 , error =  1.938113343726471e-07
Step 2 , error =  1.0790440452917247e-13
 Mesh bisection
 resetting marked-element information
 Update mesh topology
 Update clusters
 Bisection done
 Update clusters
assemble VOL element 96/96                                 
Caught SIGSEGV: segmentation fault
Collecting backtrace...
nm: /usr/lib64/libpython3.7m.so.1.0: no symbols
nm: /usr/lib64/libpython3.7m.so.1.0: no symbols
nm: /usr/lib64/libpython3.7m.so.1.0: no symbols
nm: /usr/lib64/libpython3.7m.so.1.0: no symbols
nm: /usr/lib64/libpython3.7m.so.1.0: no symbols
nm: /usr/lib64/libpython3.7m.so.1.0: no symbols
nm: /usr/lib64/libpython3.7m.so.1.0: no symbols
nm: /usr/lib64/libpython3.7m.so.1.0: no symbols
nm: /usr/lib64/libpython3.7m.so.1.0: no symbols
#1      /home/MATH/wahl/Applications/NGSolve/inst//lib/libngcore.so(+0x198a7) [0x7f9fcbf7a8a7]
#2      /lib64/libc.so.6(+0x3c150) [0x7f9fcd1a1150]
#3      in ngla::TransposeMatrix(ngla::SparseMatrixTM<double> const&)
           at ??:?
#4      in ngla::SparseMatrix<double, double, double>::Restrict(ngla::SparseMatrixTM<double> const&, std::shared_ptr<ngla::BaseSparseMatrix>) const
           at ??:?
#5      in ngcomp::BilinearForm::GalerkinProjection()
           at ??:?
#6      in ngmg::MultigridPreconditioner::Update()
           at ??:?
#7      in ngcomp::MGPreconditioner::Update()
           at ??:?
#8      in ngcomp::S_BilinearForm<double>::DoAssemble(ngcore::LocalHeap&)
           at ??:?
#9      in ngcomp::BilinearForm::Assemble(ngcore::LocalHeap&)
           at bilinearform.cpp:?
#10     /home/MATH/wahl/Applications/NGSolve/inst//lib/libngcomp.so(+0x95574c) [0x7f9fb63b874c]
#11     /home/MATH/wahl/Applications/NGSolve/inst//lib/libngcomp.so(+0x70dbfe) [0x7f9fb6170bfe]
#12     in �.�!�U
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#13     in ���!�U
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#14     /usr/lib64/libpython3.7m.so.1.0(+0x15e779) [0x7f9fccf70779]
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#19     /usr/lib64/libpython3.7m.so.1.0(+0x208d93) [0x7f9fcd01ad93]
#20     in �e�!�U
           at ??:0
#21     in ���!�U
           at ??:0
#22     /usr/lib64/libpython3.7m.so.1.0(+0x20fc5c) [0x7f9fcd021c5c]
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#24     in ���!�U
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