.. AlphaTwirl documentation master file, created by sphinx-quickstart on Sat May 23 14:38:44 2015. You can adapt this file completely to your liking, but it should at least contain the root `toctree` directive. | | .. image:: ../images/AlphaTwirl.png :width: 300px :alt: alphatwirl | *AlphaTwirl* is a python library that loops over event data and summarizes them into multi-dimensional categorical data as data frames. Event data, input to AlphaTwirl, are data with one entry (or row) for one event: for example, data in `ROOT `_ `TTrees `_ with one entry per collision event of an `LHC `_ experiment at `CERN `_. Event data are often large---too large to be loaded in memory---because they have as many entries as events. Multi-dimensional categorical data, the output of AlphaTwirl, have one row for one category. They are usually small---small enough to be loaded in memory---because they only have as many rows as categories. Users can, for example, import them as data frames into `R `_ and `pandas `_, which usually load all data in memory, and can perform categorical data analyses with a rich set of data operations available in R and pandas. Contents: .. toctree:: :maxdepth: 4 alphatwirl Indices and tables ================== * :ref:`genindex` * :ref:`modindex` * :ref:`search`