Restarts for multigas and GIR carbon

[SallyDa]

Hello FaIR developers,

First of all I just want to say that I think this model is a really nice idea!

I recently started working with @Hans-PeterH and @myrti, looking at companies contributions to global warming. We are using FaIR in a web app and want to run it multiple times on the fly, so we are trying to save computational time as much as possible. As we are only changing future emissions and the historical part remains the same, restarts from present day seem like a good option.

This pr adds restart functionality for multi-gas mode and the GIR carbon cycle. Additionally I found and fixed a bug when trying to use CO2-only mode with the GIR carbon cycle (line 752 old, 826 new of fair/forward.py).

Finally, I am sorry that I added even more lines of code and more if else statements to an already very long function. I did think briefly about trying to clean up the code a bit, but I know you are already working on that. I am so excited for v2!! In the meantime though, it would be great if we could get this pr merged and a new v1 release that we can use for our tool.

Thanks, Sally

[codecov[bot]]

Codecov Report

Merging #94 (551d9e9) into master (31c4ae0) will increase coverage by 0.46%. The diff coverage is 96.36%.

@@            Coverage Diff             @@
##           master      #94      +/-   ##
==========================================
+ Coverage   95.07%   95.54%   +0.46%     
==========================================
  Files          42       42              
  Lines        1787     1818      +31     
==========================================
+ Hits         1699     1737      +38     
+ Misses         88       81       -7     

Impacted Files	Coverage Δ
fair/forward.py	84.73% <96.36%> (+2.87%)	:arrow_up:

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[SallyDa]

Hello,

This pull request has been here for a while now. It would be nice to get an update from someone (@chrisroadmap?) to find out whether this is something you are interested in merging at some point and if so, when you would have time to look at it. If there's anything else you would like me to do, please just let me know.

Sally

[myrti]

Hello,

To reiterate Sally's request: Could you please let us know your verdict on this change. Using the restart option leads to a significant speed increase for running different future scenarios which makes it valuable to us.

Thank you!

[chrisroadmap]

Sorry, I have a lot on my plate at the minute... I will check this as soon as I get a chance!

[chrisroadmap]

Hey @SallyDa, could you rebase the latest master branch on to this pull request? I think it will then be straightforward to merge it.

[chrisroadmap]

I'll check what needs to be done with #95 and roll this into a v1.6.3 release later today. Sorry I'm so slow with all of this!

[SallyDa]

Thanks a lot @chrisroadmap, this is really great news for us!!