LCIO collections of Tracks and other objects can be read into ROOT using the LCIO C++ API.
These are instructions for setting up LCIO and ROOT to work with each other.
I use the LCIO trunk from June 28 2012, ROOT version 5.34, and CMake 2.8.6, and I am building on a 64-bit RHEL 5.8 machine.
These instructions should work on most varieties of Linux, will probably work on OSX (not tried yet), and might work on Windows with some modifications (not covered here).
Setup and Build Commands
Any command that starts with "export" will generally need to be re-executed to run the various examples that I cover below.
Setup the ROOT environment. I do not cover how to build and install ROOT.
Build LCIO with the ROOT class dictionaries.
Once ROOT and LCIO are setup, you'll want to create a setup script that contains something like the following...
You can call this script 'mysetup.sh'. This should allow you to execute the examples covered below. You will need to execute 'source mysetup.sh' from your shell before proceeding with your analysis session.
Basic Analysis Test
Example Event Dump
The anajob.C example should produce event dumps that look like this...
I have modified the LCIO copy of anajob.C to produce some histograms from Track information. This example reads a collection from an LCIO file and creates a collection of Tracks. Then it histograms some basic information from these objects. It can be used as a basis for further analysis work.
Writing and Reading ROOT Files
The example writeEventTree.C can be used to produce a ROOT output file.
First the environment needs to be setup so that ROOT can find the LCIO class dictionary.
Then from the ROOT command line...
This will write the file lcioEventTree.root in the current directory.
Now load a browser to look at the file.
Or try to read it back.
Should you want to dive deeper into analysis, investigate the LCIO C++ API