feat: abstracting accumulation

[b8raoult]

Description

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Issue Number

Code Compatibility

• I have performed a self-review of my code

Code Performance and Testing

• I have added tests that prove my fix is effective or that my feature works
• I ran the complete Pytest test suite locally, and they pass

Dependencies

• I have ensured that the code is still pip-installable after the changes and runs
• I have tested that new dependencies themselves are pip-installable.

Documentation

• My code follows the style guidelines of this project
• I have updated the documentation and docstrings to reflect the changes
• I have added comments to my code, particularly in hard-to-understand areas

Additional Notes

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📚 Documentation preview 📚: https://anemoi-datasets--326.org.readthedocs.build/en/326/

[flyIchtus]

Hello

Anything we can do to help getting this merged @flyIchtus ? It would be very useful for us as we are in the process of generating new datasets.

Hello @frazane, happy it's been useful already.

Sorry it took so long... I think the PR is ready for review as I added some docs and fixed some tiny bugs.

Now I also want to add functionality for netcdf files, but i don't have a use-case myself. I will be using IMERG dataset for this, but if you have a different netcdf dataset/specific needs i'm happy to discuss it.

[frazane]

@flyIchtus we are only using GRIB-based sources (grib-index and eventually fdb from #405 )

[frazane]

The functionality is there and I tested it successfully on my machine. Comments are mostly related to docstrings and static typing.

[mpvginde]

Hi @flyIchtus,
I'm taking a look at the PR for calculating the accumulations of CERRA-LAND taken directly from mars.
For CERRA-LAND the data_accumulation_period in mars would be 3 (only 3 forecast steps are archived), but I would want to accumlate the fields over 6 hours (accumulation_period: 6).
From the first look at the code, this is currently not supported right?

[flyIchtus]

Hi @flyIchtus, I'm taking a look at the PR for calculating the accumulations of CERRA-LAND taken directly from mars. For CERRA-LAND the data_accumulation_period in mars would be 3 (only 3 forecast steps are archived), but I would want to accumlate the fields over 6 hours (accumulation_period: 6). From the first look at the code, this is currently not supported right?

It should be, can we discuss it in DM ?

[floriankrb]

This PR should go on top of (be merged after) this other one #379 which refactors a lot.

I mention this becuase this PR changes action.py and result.py and this may create a conflict to solve.

[floriankrb]

ecmwf/anemoi-transform#168 may show a related use case.