Summary and Schedule

This tutorial introduces the concepts and code patterns needed to implement reconstruction algorithms in EICrecon, the ePIC reconstruction software. It walks through building a factory, calling and parameterizing it, adding an algorithm, working with PODIO collections, and putting everything together into a working electron finder.

Prerequisite

Prerequisites

• A GitHub account
• A working eic-shell environment

See the Setup page for details.

	Setup Instructions	Download files required for the lesson
Duration: 00h 00m	1. Introduction	What is the physics goal of the reconstruction algorithm we will build? What information do we need to accomplish this goal?
Duration: 00h 05m	2. Creating a factory	What is the difference between an algorithm and a factory? How is EICrecon’s plugin structure organized, and where do new factories go? Which factory base class should I use, and what does its interface look like?
Duration: 00h 16m	3. Calling a factory	How do I wire a factory into JANA2 using a factory generator? How do I make my factory’s outputs available, either once-off or every time?
Duration: 00h 27m	4. Parameterizing a factory	How do I give a factory configurable parameters? How do I override those parameters from a generator or the command line? How do I access services such as geometry from a factory?
Duration: 00h 32m	5. Adding an algorithm	What is the difference between a factory and an algorithm? Where does algorithm code live, what does its interface look like, and how does a factory call it?
Duration: 00h 38m	6. Working with PODIO	What is PODIO and why does the EIC data model use it? How do I create and fill PODIO collections, and what is a subset collection?
Duration: 00h 44m	7. Putting everything together	How do the factory, algorithm, config, and generator fit together in the final electron finder?
Duration: 00h 49m	Finish

The actual schedule may vary slightly depending on the topics and exercises chosen by the instructor.

To follow along with this tutorial you will need:

1. A GitHub account (sign up here).
2. A working eic-shell environment. If you do not have one yet, first complete the Setting Up Your EIC Environment tutorial.
3. A local checkout of EICrecon that you can build from inside eic-shell. Building EICrecon from source can take a while, so do this in advance of the session. Build instructions are in the EICrecon README.

You should also be comfortable reading and writing C++.