Getting Started with ROOT

The ROOT framework is the software environment we use for data taking, analysis and visualisation.

We recommend that you use the ROOT version centrally installed on our servers. See the ROOT section in the Tier-3 user guide for details on setting up ROOT. It is not recommended to add these commands to your startup as it might interfere with the use of CMSSW.

If you do need or want to install it your self, e.g on your laptop, follow the description in:

• Chapter 28: Install and build of ROOT

You should make yourself familiar with ROOT by reading parts of the users guide, and running (and understanding!) the turorials. We have broken them up in a few steps:

General Introduction

• Chapter 01: Introduction
• Chapter 02: Getting started (note on our tier2/3 this is what the setup scripts do)
• Chapter 06: A little C++
• Chapter 07: CINT, the C++ interpreter
• Chapter 16: Adding a class

• Starting an interactive session
• The "Hello World" example
• Using CINT
• Adding classes
• Creating dictionaries

Histograms

• Chapter 03: Histograms
• Chapter 04: Graphs

• Creating histograms
• More on histograms
• Fitting an histogram
• Graphs with errors
• 2dim drawing options

Ntuples and Trees

• Chapter 12: Trees

• Ntuples and selections
• Creating ROOT trees
• Reading events from ROOT trees

PROOF

• Chapter 25: PROOF, Parallel Processing

Run the example described in the README file in $ROOTSYS/test/ProofBench.

-- ConstantinLoizides - 12 Apr 2006 - back to MITHIG