HGCAL Trigger Geometry Utilities

This is a Python package used to manipulate geometries, like:

• Mapping one geometry to an other
• Finding nearest neighbors

Installation

First clone the package:

git clone git@github.com:PFCal-dev/GeometryUtilities.git GeometryUtilities

This package depends on several python packages, listed in requirements.txt:

• attrs
• scipy
• numpy
• root-numpy
• Shapely

In general it is better to encapsulate these packages inside a virtual environment (using for instance virtualenvwrapper).

It also depends on the GEOS C++ library used by Shapely.

On SLC6 lxplus, the default versions of python and ROOT are antique, so a couple of setup commands are needed to have a working environment. The following script should be sourced each time to setup Python, ROOT, and the virtual environment (outside a CMSSW environment).

source init_env_lxplus.sh

It will install everything the first time it is called (in particular it will download and compile GEOS, which takes some time). The GEOS library will be installed in ~/.local, so ~/.local/lib should be included in LD_LIBRARY_PATH. Then, once everything is already installed it will just activate the virtual environment.

If it worked correctly the terminal prompt should be prefixed with (geometry), meaning that you are inside the virtual environment. To leave the virtual environment, just type deactivate.

On machines other than lxplus, the same thing can be done, just the Python and ROOT setup at the beginning of the script would need to be modified.

Usage

The package code is located in geometry. This code is used from scripts located in the scripts directory. The scripts currently available are:

• produce_cell_mapping_pickle.py: produce the mapping from the CMSSW geometry to the Zoltan/Split geomeytry
• produce_panel_mapping_pickle.py: produce the panels mapping
• produce_mappings_cmssw.py: take pickle files from the previous scripts and produce mapping files that can be read by the CMSSW trigger geometry
• compare_cell_mappings.py: check the consistency of mapping files, for instance based on different layers
• produce_cell_neighbors_pickle.py: produce the map of neighbors for the Zoltan/Split geometry
• produce_neighbors_cmssw.py: tacke pickle file from the previous script and produce the corresponding CMSSW-compatible file
• check_neighbors.py: performs basic checks on neighbor maps