Maximum number of iterations taken when calling eigen solver from Arpack

[remann2]

Thank you for sharing this nice package for mode analysis!

When running the demo https://helgegehring.github.io/femwell/julia/waveguide.html, when running
modes = calculate_modes(model, ε ∘ τ, λ = 1.55, num = 2, order = 1), I encounter the following error.

ERROR: ┌ Error: XYAUPD_Exception: Maximum number of iterations taken. All possible eigenvalues of OP has been found.
│ IPARAM(5) returns the number of wanted converged Ritz values.
│ info = 1
└ @ Arpack ~/.julia/packages/Arpack/FCvNd/src/libarpack.jl:47

To reproduce it is to clone the repo, instantiate it in julia, install the femwell in python, run the Femwell.jl in REPL to compile the module, change line 63 in docs/julia/waveguide.jl from using Femwell.Maxwell.Waveguide to using Main.Femwell.Maxwell.Waveguide, and run waveguide.jl.

[HelgeGehring]

Happy to hear that it helps! :)

It seems to me that you somehow managed go around the pinning of Arpack.jl to 0.5.3., 0.5.4 is broken (see JuliaLinearAlgebra/Arpack.jl#147).

Maybe we should add a warning somewhere? Or catch that error and throw a new one until Arpack.jl is fixed?

Why do you need to rename using Femwell.Maxwell.Waveguide to using Main.Femwell.Maxwell.Waveguide ? Is there something we should fix?

[remann2]

Aha! I guess when I ran the code manually (shift + enter line by line in code editor to see what really happens) under the doc folder, Julia REPL didn't realize the package layout and spun up the wrong env.

Same reason that I put the Femwell under Main scope, I guess if I just use > include("xxx/xxx.jl") in terminal it should run correctly.