avoids spawning of timeout thread if no timeout set

[wookietreiber]

fixes #253

[coveralls]

Pull Request Test Coverage Report for Build 856

• 12 of 12 (100.0%) changed or added relevant lines in 1 file are covered.
• 2 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.04%) to 89.757%

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Files with Coverage Reduction	New Missed Lines	%
spotpy/algorithms/fscabc.py	1	80.43%
spotpy/algorithms/rope.py	1	93.58%

Totals
Change from base Build 851:	-0.04%
Covered Lines:	4136
Relevant Lines:	4608

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💛 - Coveralls

[wookietreiber]

@thouska What are your recommendations regarding the coverage diff?

[thouska]

Great thank you!
As the issue is arrising with single-core usage, how about checking for that with
if not parallel == 'seq':
instaead of
if self.sim_timeout:?

[wookietreiber]

@thouska The overhead is not just with single-core usage. Generally, if you don't have/need/want a timeout, you should not need to pay the overhead cost of the extra thread and the logistics around it.

[thouska]

Ok, you are right, than we leave it like that and check for the timeout. And never mind the coverage, it varies from time to time because i have’nt set a random seed. Therefor some algorithms behave differently from one test to the other.
Your contribution will be available on pypi in spotpy version >=1.5.11 (propably published today, if not tomorrow).

[wookietreiber]

Alright, thanks for the quick response!