[bugfix] This fixes an issue when UMFPack is found and AMG with field type float is used.

The selection of UMFPack as a direct solver does not only depend on UMFPack being found, but also whether the field type is double or complex. Otherwise UMFPack cannot be used as a coarse solver in AMG. This PR fixes this issue.

@markus.blatt: Please take a look at this. @smuething: Please take a look at this.

Added 1 commit:

• d2ed3e53 - [bugfix] avoid ambiguity by using std::abs directly etc. instead of using std::abs.

Wasn't argument-dependent name lookup the reason to do the opposite…?

I don't care how it's implemented as long as it works which it does not right now. I'm using the ISTL solvers with an overloaded double class which is does not compile when using the ISTL solvers in it's current implementation. Other solutions welcome as long as they work.

Would you mind adding a test case that triggers the problem with float in a separate MR? Or is there a failing test case already?

I could imagine one of the ambiguous functions being in or included by the umfpack headers. Am I right? Which version is that?

I have revert the changes in solvers.hh. I need to investigate this a bit more.

Milestone changed to %DUNE 2.5.0

Added 45 commits:

• 1e2f4fdc...e50c4952 - 44 commits from branch master
• 2b7a6043 - [bugfix] This fixes an issue when UMFPack is found and AMG with field type float

Compare with previous version

I have merged the latest master rebased on top of it. I'll merge this if there are no objections.

I haven't tested it, but the change looks ok to me.

From the code and privately confirmed by @robert.kloefkorn, this patch disables UMFPack when using AMG with field_type float. Looks good to me and the tests have passed.

@dominic Would you mind having a look, too and merging if you think it is OK.

@dominic: Once you merged please also create the backport MR for 2.5. Thanks.

Only had a quick glance, but looks good.

Mentioned in commit 1eafb167

Status changed to merged

Mentioned in commit a313ac63

Mentioned in merge request !74 (merged)

Mentioned in commit 2dfd9a54