Simple translator from Parquet to ROOT TTree

Install: pip3 install parquet_to_root

Requires PyROOT and pyarrow. The latter can be installed via pip; the former is more complicated, but if you're reading this you probably know how to get it. (The tests in this package use miniconda: conda install -c conda-forge root.)

To run from the command line:

python3 -m parquet_to_root infile.parquet outfile.root [-t TREENAME] [--verbose]

To run from your script,

    from parquet_to_root import parquet_to_root
    parquet_to_root(parquetfile, rootfile, treename='parquettree', verbose=False)

where the default values are shown for the optional arguments.

The parquetfile argument can either be a filename string or file-like object opened in binary mode. The rootfile argument can either be a filename string or an open TFile; if a string is provided any existing file will be overwritten, while if a TFile object is provided the new tree will be added to the existing file.

This work was supported by the US Department of Energy, Office of Science, Office of High Energy Physics, under Award Number DE-SC0007890.