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Pythonic mix-ins for ROOT classes.

This package is typically used as a dependency for uproot 3.x, to define methods on the classes that are automatically generated from ROOT files. This includes histograms (TH*) and physics objects like TLorentzVectors. The reason it's a separate library is so that we can add physics-specific functionality on a shorter timescale than we can update Uproot 3 itself, which is purely an I/O package.

Occasionally, this library is used without Uproot 3, as a way to make arrays of TLorentzVectors.

Note: this package is incompatible with awkward>=1.0 and uproot>=4.0! For Lorentz vectors, use vector. Since the versions of Awkward Array and Uproot that this is compatible with are deprecated, this library is deprecated as well.


Install uproot3-methods like any other Python package:

pip install uproot3-methods               # maybe with sudo or --user, or in virtualenv


Reference documentation



Support for this work was provided by NSF cooperative agreement OAC-1836650 (IRIS-HEP), grant OAC-1450377 (DIANA/HEP) and PHY-1520942 (US-CMS LHC Ops).

Thanks especially to the gracious help of uproot3-methods contributors!