Alternative to root_numpy

[cbrisboi]

I was looking at updating hawc_hal to use uproot rather than the old ROOT interface for its .root file io and saw that a big part of the root_numpy dependency is carried over from 3ML via the dependency on threeML/io/cern_root_utils. I would generally prefer to stay consistent with file handling between 3ML and hawc_hal. Is there a preference for uproot vs the new ROOT interface? This is already an issue in hawc_hal, see threeML/hawc_hal#42

The code looks straightforward to update, but before I run off and implement something that is not preferred, I thought asking would be wise first.

[grburgess]

@cbrisboi I think the other part of ROOT that is used in in the ROOT minimizers. Is this also a simple fix?

[cbrisboi]

Since root_numpy is only for file io, this would be (to my mind) somewhat separate from the minimizers. It appears that in the threeML repo(rather than hawc_hal), the only place this code is used is in the VERITASLike plugin, although I am not taking responsibility for that plugin, as I am not a member of VERITAS.

[grburgess]

So this is not the same thing?

https://github.com/threeML/threeML/blob/master/threeML/minimizer/ROOT_minimizer.py#L3

[cbrisboi]

No, thats using ROOT, rather than root_numpy
See https://github.com/threeML/threeML/blob/master/threeML/io/cern_root_utils/tobject_to_numpy.py#L2

[grburgess]

Aha! Well, I'm all fine with it, but @ndilalla just did all the root stuff, so he should chime in.

[ndilalla]

I am all in for getting rid of root_numpy and using uproot. @cbrisboi do you know which requirements this new package has?

[cbrisboi]

On github, the only strict dependency is numpy, although if going through conda, which I suspect is preferred, the dependencies are ( using conda info uproot=4.0.0 and then copying the dependencies for python 3.7):

Here is the relevant github page https://github.com/scikit-hep/uproot4

dependencies:
    awkward >=1
    lz4
    python >=3.7,<3.8.0a0
    python-xxhash
    python_abi 3.7.* *_cp37m
    uproot-base
    xrootd
    zstandard

[grburgess]

Wow. This package is amazing.

[github-actions]

This issue has become stale. Is there an update? We will close in 15 days

[grburgess]

@cbrisboi will there be any progress on this? Otherwise, we need to go ahead and close or assign someone else.

[github-actions]

This issue has become stale. Is there an update? We will close in 15 days