ROOT/PROOF Workshop

Authors

Arsen Hayrapetyan, Martin Vala

Abstract

ROOT is an object-oriented framework for large-scale data analysis. PROOF, the Parallel Root Facility, is an extension of ROOT which enables interactive parallel large-scale analysis on a cluster. PROOF Lite, a dedicated version of PROOF, allows to analyse the data on a multi-core computer. In the first part of ROOT/PROOF tutorial the participants will be introduced to ROOT and tools for analysis and visualisation of the data on a desktop machine. Participants will learn how to design and use a custom event class for analysis of data stored in ROOT tree structure. This will be followed by the second part where the structure of the PROOF system and tree/selector-based analysis will be explained. Participants will run analysis tasks on multi-core desktop systems and on a dedicated PROOF cluster in practical exercises.

Prerequisites

• Login/password provided by School organisers in your personal information sheet to connect to UI (user interface) machines. Machines will have ROOT software installed.

• If you plan to use your laptop instead of UI you should have installed ROOT on the laptop. You can download ROOT here.

ROOT

• Introduction to ROOT
• Basic ROOT features: Data containers, visualisation, GUI, CLI
• Trees and chains
• Events. Sample event class creation
• Selectors
• Analysis of data stored in a chain

PROOF

• Introduction to PROOF
• PROOF analysis schema
• Analysing data with PROOF Lite
• PAR files

• Datasets
• Analysis with PROOF

Exercises

1. Using ROOT CLI

1. Creation of 1-D histogram with ROOT macro

1. Using ROOT GUI

1. Creation of a sample event class

1. Creation of a tree containing events from previous exercise

1. Tree content visualisation

1. Creation of a selector for data analysis

1. Analysis of the data stored in a chain, locally

1. Creation of a PAR file

1. Data analysis with PROOF Lite

1. Dataset management

1. Data analysis with PROOF