arpackmm: add --slvDrtPvtThd option.

[fghoussen]

Pull request purpose

arpackmm: enhancement

Detailed changes proposed in this pull request

add control on pivot threshold if direct solver is used.

[fghoussen]

Should not increase coverage ! :D
I will likely PR another small feature by the end of the day or tomorrow : after that 3.7 should be OK (1st "good" enough version of arpackmm - probably add more for versions > 3.7 as I will need it).

[fghoussen]

Oh... Stupid : make_unique is likely C++14 ? And compiler option is C++11.
Should I move to C++14 ? Or modify the code to compile with C++11 ?
Any suggestion to bypass this stupid thing is welcome !...

[sylvestre]

C++14 is a bit too early :/ (I know)

[fghoussen]

OK, this is just for testing.
This patch is logical to be added now, but, not so central anyway: can wait after 3.7.

[coveralls]

Pull Request Test Coverage Report for Build 657

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 74.783%

---

Totals
Change from base Build 654:	0.0%
Covered Lines:	5080
Relevant Lines:	6793

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💛 - Coveralls

[fghoussen]

@sylvestre : turns out to be OK ! Do you take it ?

[sylvestre]

Sorry, no, I don't want to have C++14 as mandatory dep yet.

[sylvestre]

Sorry about that, please reopen

[fghoussen]

Sorry, no, I don't want to have C++14 as mandatory dep yet.

OK, got it. I'll rewrite it with C++11.

Sorry about that, please reopen

OK. For master, consider reset --hard HEAD~2 ?... As you like.
Seems I can't reopen a merged PR. I'll create a new PR for this.

[sylvestre]

Done, thanks

[fghoussen]

Done, thanks

OK, I'll PR back again quite soon !