Test complex elliptic DG operator

[nilsvu]

Proposed changes

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Further comments

[nilsvu]

@wthrowe would you be able to review this one as well? (continuing the quest of DG with complex numbers)

[wthrowe]

The clang-tidy warnings look right, at least for these last two. Why should they be ignored? Similar comments for the other file.

[nilsvu]

I don't want functions in this class be able to modify this value. It's the user-defined value from options that gets passed down to this struct. I don't understand why clang-tidy want's me to remove the const when really I want it to be const.

[wthrowe]

The documentation links to the core guidelines rule and some extra reading. I don't agree with everything in there, but that section seems pretty good. The short answer for your class is that the functions already can't modify the value because they are const member functions.

[nilsvu]

Ok makes sense, I removed the const

[wthrowe]

Looks good.