Segmentation fault in ArnoldiSolver

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1

I am getting a segmentation fault in the ArnoldiSolver function. I am using complex valued functions in H(curl) in 2D and the problem involves a pair of spaces

fes=HCurl(mesh,order=porder,complex=True)
fes0=HCurl(mesh,order=porder,dirichlet=“PEC|B”,complex=True)
V=FESpace([fes0,fes])

Assembly of the matrices seems to progress with no problems.

On a coarse mesh with cubic elements (25,992 DoF) the code works well and gives expected results. But when I try to get a more accurate solution with a finer grid in the region of interest I get this:

Generate Mesh from spline geometry
Number of DoFs: 209544
About to start ArnoldiSolver
zsh: segmentation fault netgen trans.py

The code is running on a Mac Pro (using OS 12.0.1 Monterey) and I am using NGSolve-6.2.2105.

I hope someone can help me avoid this issue. Thanks in advance!

Best
Peter

2

Dear Peter,
my personal experience with solving eigenvalue problem for fine mesh is that the best option is to use an outside solver such as SLEPc, this option worked very well for me.
Kind regards,
Umberto