[examples] Add convenience utility for FastAMG preconditioner and use it in Poisson example

Unfortunately, Dune::FastAMG cannot be created without manually creating and filling parameter objects before. This adds a convenience function to do this to reduce boiler plate code in the examples. Furthermore AMG is now used in the Poisson-example and its matrix and vector types are fixed (no more artificial blocking).

enabled an automatic merge when all merge checks for 83048c19 pass

aborted the automatic merge because the source branch was updated. Learn more.

added 1 commit

• aa75e34d - [examples] Only enable makeFastAMG in version >=2.10

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There's something fishy in the CI. This check

#if DUNE_VERSION_GT(DUNE_ISTL, 2, 10)

seems to be true in the dune:2.10 debian-11 acc-10 C++20 job.

And dune:git debian-11 gcc-10 C++20 seems to lack behind dune-istl master.

After rebasing on !250 (merged) the remaining 2.10 job passes. Now we need to fix the jobs against master.

!251 (merged) is an attempt to avoid the outdated dune:git-* images.

Rebased on !251 (merged) to check if this solves the issues we have here.

added 1 commit

• 006811e7 - [examples] Use more fine-grained version testing for FastAMG

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added 5 commits

• 2aa99ae6 - [CI] Use 2.10 image for the jobs testing against 2.10
• 519ef661 - [examples] Add convenience functions for creating a Dune::FastAMG preconditioner
• c2261c09 - [examples] Improve poisson-pq2.cc
• c1d478f5 - [examples] Only enable makeFastAMG in version >=2.10
• aa29d743 - [examples] Use more fine-grained version testing for FastAMG

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added 1 commit

• 261c233b - [examples] Use more fine-grained version testing for FastAMG

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mentioned in merge request !250 (merged)

added 6 commits

• f598f033 - 1 commit from branch master
• e80925e8 - [CI] Stop using images for git-based CI jobs
• ece45a34 - [examples] Add convenience functions for creating a Dune::FastAMG preconditioner
• 71cdb041 - [examples] Improve poisson-pq2.cc
• 230a5465 - [examples] Only enable makeFastAMG in version >=2.10
• 65c8961a - [examples] Use more fine-grained version testing for FastAMG

Compare with previous version

mentioned in merge request !251 (merged)

added 5 commits

• c4921b6d - 1 commit from branch master
• 0007a32f - [examples] Add convenience functions for creating a Dune::FastAMG preconditioner
• e208f1d0 - [examples] Improve poisson-pq2.cc
• b92f96cc - [examples] Only enable makeFastAMG in version >=2.10
• 0558c96c - [examples] Use more fine-grained version testing for FastAMG

Compare with previous version

enabled an automatic merge when all merge checks for 0558c96c pass

merged

mentioned in commit f6af07e2