##ROOT DIFF

Introduction

This program can be used to compare two ROOT files. ROOT file is used for storing serialized root object, which used by ROOT Data Analysis Framework.

There are two available mode for comparing

1. CC - COMPRESSED COMPARE, which compare the compressed object buffer.
2. UC - UNCOMPRESSED COMPARE, which uncompress the object buffer and compare.

And there are three levels of equivalence

1. STRUCTRUAL-EQUAL - compare the hierarchical structure of two ROOT files.
2. CONTENT-EQUAL - ROOT files should be logic equivalence and objects from two ROOT files should be equal to each other on byte level.
3. BITWIST-EQUAL - ROOT files should be strictly equivalence and objects from two ROOT files should have same timestamp.

Installation

1. Software requirements

   • ROOT 6.02 or above version
   • g++ 4.6.7 or above version

2. How to Install

   • Install on earth.crc.nd.edu If you have access to earth.crc.nd.edu Before building please remove the gcc module and load the root, python/2.7.8 module by typing following commands:

     module rm gcc
     module load root python/2.7.8

     Then you can build the program by typing

     make

     After build, root_diff in bin/ can be used to compare the two ROOT files, more details can be found through bin/root_diff -h

   • Using docker image If you have docker daemon running on your machine, a docker image is avaliable in docker/ directory. You can build the image by typing

     docker build -t <image_name:tag> .

     Then you can launch docker container with an interactive bash shell by typing

     docker run -it <image_name:tag> 

Usage

Following are examples of using root_diff, *.root files used in examples can be found in sample_root_files folder.

1. Two ROOT files are exactlly equal to each other

   bin/root_diff -m CC -l r1_r1.log sample_root_files/r1.root sample_root_files/r1.root

   The expected output will be:

    -----------------------------------------------------------
    file 1: sample_root_files/r1.root
    file 2: sample_root_files/r1.root
    The comparison mode is: COMPRESS COMPARE
    file 1 is EQUAL to file 2.
    The agreement level is EXACT
    Details can be found in r1_r1.log
    -----------------------------------------------------------
   

2. Two ROOT files are stricly equal to each other

   bin/root_diff -m UC -l fx1_fx2.log sample_root_files/fx1.root sample_root_files/fx2.root

   The expected output will be:

    -----------------------------------------------------------
    file 1: sample_root_files/fx1.root
    file 2: sample_root_files/fx2.root
    The comparison mode is: COMPRESS COMPARE
    file 1 is EQUAL to file 2.
    The agreement level is STRICT
    Details can be found in fx1_fx2.log
    -----------------------------------------------------------
   

3. Two ROOT files are logically equal to each other

   bin/root_diff -m CC -l r1_r2.log sample_root_files/r1.root sample_root_files/r2.root

   The expected output will be:

    -----------------------------------------------------------
    file 1: sample_root_files/r1.root
    file 2: sample_root_files/r2.root
    The comparison mode is: COMPRESS COMPARE
    file 1 is EQUAL to file 2.
    The agreement level is LOGICAL
    Details can be found in r1_r2.log
    -----------------------------------------------------------