Backend for columnar, fully orchestrated HEP analyses with pure Python, law and order.

This project is for use within the Ghent CMS group. Original source hosted at GitHub.

Quickstart

To create an analysis using columnflow, it is recommended to start from a predefined template (located in analysis_templates). The following command (no previous git clone required) interactively asks for a handful of names and settings, and creates a minimal, yet fully functioning project structure for you! The 'cms_minimal' flavor corresponds to the template provided by columnflow itself. 'Ghent_template' provides a more extensive example.

bash -c "$(curl -Ls https://raw.githubusercontent.com/GhentAnalysis/columnflow/main/create_analysis.sh)"

At the end of the setup, you will see further instructions and suggestions to run your first analysis tasks (example below).

Setup successfull! The next steps are:

1. Setup the repository and install the environment.
   > cd
   > source setup.sh [recommended_yet_optional_setup_name]

2. Run local tests & linting checks to verify that the analysis is setup correctly.
   > ./tests/run_all

3. Create a GRID proxy if you intend to run tasks that need one
   > voms-proxy-init -rfc -valid 196:00

4. Checkout the 'Getting started' guide to run your first tasks.
   https://columnflow.readthedocs.io/en/stable/start.html

   Suggestions for tasks to run:

   a) Run the 'calibration -> selection -> reduction' pipeline for the first file (--branch 0) of the
      default dataset using the default calibrator and default selector
      (enter the command below and 'tab-tab' to see all arguments or add --help for help)
      > law run cf.ReduceEvents --version dev1 --branch 0

      Verify what you just run by adding '--print-status -1' (-1 = fully recursive)
      > law run cf.ReduceEvents --version dev1 --branch 0 --print-status -1

   b) Create the jet1_pt distribution for the single top datasets
      (if you have an image/pdf viewer installed, add it via '--view-cmd <binary>')
      > law run cf.PlotVariables1D --version dev1 --datasets 'st*' --variables jet1_pt

      Again, verify what you just ran, now with recursion depth 4
      > law run cf.PlotVariables1D --version dev1 --datasets 'st*' --variables jet1_pt --print-status 4

   c) Include the ttbar dataset and also plot jet1_eta
      > law run cf.PlotVariables1D --version dev1 --datasets 'tt*,st*' --variables jet1_pt,jet1_eta

For a better overview of the tasks that are triggered by the commands below, checkout the current (yet stylized) task graph.

Other projects and original developers

You can find a list of other projects using columnflow on the original github. The main contributors to columnflow are also listed there.

Development

• Source hosted at GitHub
• Report issues, questions, feature requests for columnflow to GitHub Issues