MPI testing

[claireh93]

Further testing to MPI to check answers are the same under different numbers of processes.
Add gather_abundance() to pull all abundances to the root node in the correct order.

[codecov]

Codecov Report

Merging #66 (be08ad3) into main (0fd854e) will increase coverage by 0.19%.
The diff coverage is 88.88%.

@@            Coverage Diff             @@
##             main      #66      +/-   ##
==========================================
+ Coverage   72.47%   72.66%   +0.19%     
==========================================
  Files          26       26              
  Lines        1951     1961      +10     
==========================================
+ Hits         1414     1425      +11     
+ Misses        537      536       -1     

Impacted Files	Coverage Δ
src/EcoSISTEM.jl	100.00% <ø> (ø)
src/Ecosystem.jl	75.62% <ø> (ø)
src/MPIEcosystem.jl	52.94% <88.88%> (+5.48%)	⬆️
src/MPILandscape.jl	100.00% <0.00%> (+8.00%)	⬆️

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[coveralls]

Pull Request Test Coverage Report for Build 1051907321

• 8 of 9 (88.89%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.2%) to 55.207%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/MPIEcosystem.jl	8	9	88.89%

Totals
Change from base Build 1029465038:	0.2%
Covered Lines:	1442
Relevant Lines:	2612

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💛 - Coveralls

[claireh93]

@richardreeve I think this is ready for you to have a look at now

[richardreeve]

Generally looks okay, and maybe we can ignore the code coverage / testing problem for now, but if you can see a way of fixing it, that would be great...

[richardreeve]

@claireh93 I see your problem here. I hadn't realised this never worked before. For the time being your code works, so let's stick with it and remove the allocation later. It's not easy at all to see how to fix this. I think fundamentally we may need something like a view into an array - possibly in the root process - or distributed calculation of the diversities and abundances...

So, assuming this works I think we should just merge it as is.

[richardreeve]

Looks good to me now.

[richardreeve]

PS Another issue I noticed is that (as I'm sure you've noticed) JLD is broken and generates warnings - we need to move away from it I guess. I don't know if the solution is to use the data pipeline or to switch to JLD2, but I'll create an issue about that too. EDIT: now done - #71