The unofficial Coffea tutorial

Welcome to the unofficial coffea tutorial, written by the CMS analysis group at the University of Maryland, College Park!

The webpage version of this tutorial have be found here which is generated automatically from this GitHub repository.

This set of documentations aims to help people coming for a traditional C++/python event loop based analysis work flow get started with the concepts and tools used in coffea, a new analysis framework based around array manipulation. While having overlaps with the official documentation, this tutorial provides more introductory material and examples that doesn’t fit with typical documentation formats, as well as provide concrete snippets picked up by the team at UMD during analysis using coffea, to help people who are struggling with the new syntax to use as guidelines as to how to get started writing their own analysis code with coffea and similar tools.

We will point extensively to the official documentation whenever possible, but the reading here should be nearly standalone, enough for beginners to get started, while providing adequate information for the more advanced user to find the information they need. The order of the tutorial will roughly be in the order that is typically needed for a new comer to get started.

• Installing a coffea environment
  • Copy and paste commands
  • Installing and activating coffea the involved way
  • Installing the tutorial
• Navigating jupyter notebooks
  • More information regarding starting a notebook server
  • Navigating a server and notebook session
  • Understanding cells
  • Library and imports
• Learning the awkward arrays syntax
  • Basic object and event selection
  • Object storage and collection creation
  • Comparing array based computations and loop based computation
  • More on index notation
  • Calculation with objects
  • When all else fails - numba for loops
• Coffea processors
  • A very simple processor – understanding output
  • Scaling up calculations – process executors
• Writting coffea Schema files
  • Create collections
  • Create behavior
  • Nested jagged array implementation
  • Inherit from NanoEvents
• Histogram processing in Coffea
  • Histogram construction in computation
  • Histogram slicing and truncation
  • More axis types
  • More fill types
• Example: Higgs to 4 Muons
  • Write the previous code again within processor framwork
• Handy snippets
  • Awkward array snippets
  • Processor snippets
• Contributing to the tutorial repository