Add Tpetra-based MueLu tutorial driver and fix hands-on.py (without rebase)

[PhilipOesterlePekrun]

Equivalent to #29 but without rebasing. That is, some ctests would fail when this is merged into jhux2 due to a not-yet-present change in Galeri at this point. But, it will succeed when merged into the main Trilinos repository's develop branch (so, the tests in trilinos#14357 should still succeed when this is merged into jhux2).

@mayrmt
@jhux2

@trilinos/MueLu

Motivation

This change serves mainly to migrate the executables/drivers used in hands-on.py from the Epetra to Tpetra backend. This was most easily done by reducing the number of .cpp files--which were doing a lot of the same things--into a single general TutorialDriver.cpp. This is now is the driver for Laplace2D, Recirc2D, the challenge problems, and any future problem types we might want to introduce.

Details

The challenge problems are not exactly the same as before because https://trilinos.org/wordpress/wp-content/uploads/2015/07/MueLu_tutorial_challenges.tar.gz is currently not accessible, but they still serve the same purpose (inefficient reference xml, which the user should try to optimize).

ScalingTest.cpp and ScalingTestParamList.cpp were removed for now because there is no explicit mention of scaling in the tutorial, and much of the functionality was unrelated and convoluted (especially if a tutorial user wants to look into the files directly). For the includeliterals in the "C++ Interface" subsection of the "Using MueLu in User Applications" section, the shorter Tutorial_cppInterface.cpp is instead used, which concisely and cleanly shows the C++ interface without using an xml file.

The CMakeLists.txt of test/tutorial/ was also streamlined to test the TutorialDriver.cpp with xml files which are explicitly mentioned in the tutorial.

The TutorialDriver.cpp now writes the outputs example<PID>.txt, which are to be used for gnuplots in hands-on.py, as in the original Epetra version of laplace2d.cpp. Some small fixes in hands-on.py ensure that this functionality works properly now.

Related Issues

Part of trilinos#14357

Stakeholder Feedback

Testing

[github-actions]

CDash for AT1 results [Only accessible from Sandia networks]
CDash for AT2 results [Currently only accessible from Sandia networks]

[PhilipOesterlePekrun]

I am honestly super confused why clang-format is failing. The format_patch has a bunch of global files, not any of the files I edited in my commits. Even the only MueLu file, test/tutorial/MLParameterList.cpp, is one that I did not touch.

[mayrmt]

@PhilipOesterlePekrun I am fine with the current changes.

@jhux2, how should we proceed? Can we merge into your branch?

[jhux2]

@PhilipOesterlePekrun This looks good. It looks like laplace2d.cpp serves as the driver for the challenge problems. Have I got that right? If so, maybe it could renamed to something else. Anyway, that's a minor quibble, I'm fine merging this in as-is.

[PhilipOesterlePekrun]

@jhux2 Sorry about that, I forgot to remove laplace2d.cpp. This is meant to be replaced by the general TutorialDriver.cpp. Tutorial_cppInterface.cpp also hard codes the Laplace2D problem type, and is meant as a concise, simple implementation and for some literalincludes.

[PhilipOesterlePekrun]

Thanks!

[jhux2]

@mayrmt @PhilipOesterlePekrun Any objections if I squash commits so that we can merge to Trilinos?

[PhilipOesterlePekrun]

@jhux2 No objections from my side.

[mayrmt]

@jhux2 feel free to go ahead!

[jhux2]

Great. Just to clarify, in the branch https://github.com/jhux2/Trilinos/tree/new-muelu-read-the-docs, there are ~80 older commits by @mayrmt and @GrahamBenHarper that are missing a sign-off in their commit messages (because they predate that requirement).

Is it ok if I squash those commits? I would need to sign off myself. I would indicate in the commit that Matthias and Graham were the original authors.

[mayrmt]

@jhux2 I am fine with that.

[mayrmt]

@jhux2 A former student, @Max-pert, also contributed. He mainly created the website files for the tutorial. I don't know, if he committed himself or if I did that for him, but he did the work. Feel free to indicate his contribution as well.