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DynamicTTreeReader

This class is an interface to any ROOT TTree. It aims to ease the access of an existing TTree: the user needs only to define a set of precompiler variables containing the branches to be accessed (and their respective types).

The interface will be created by a set of precompiler macros in the form of a Class from which one can access the TTree branches.

A set of methods is also defined in order to provide a simple way to handle iteration over all the TTree entries.

How to define a new interface:

• Include the DTR header file:

  #include "interface/DynamicTTreeReader.h"
      

• define the name of the interface class and the set of branches:

  #define DYNAMIC_TREE_NAME DynamicTTreeReader
  
  #define DATA_TABLE                              \
  DATA(int, i)                                    \
  DATA(float, f)
  
  #define DATA_VECT_TABLE                         \
  DATA(int, vi, i)
  
  #define DATA_CLASS_TABLE                        \
  DATA(std::string, s)
      

• include the precompiler macros to generate the class body and methods: the following line must be placed below the branches definition

  #include "src/DynamicTTreeReader.cc"
      

• test/DTR_SimpleExample.cpp contains a working example.

Branches type

Following the different ways in which basic type variables, c-arrays and classes are handled inside the ROOT TTree class there are three different types of branches definition:

• DATA_TABLE(type, name): for basic type branches.
• DATA_VECT_TABLE(type, name, size): for c-arrays.
• DATA_CLASS_TABLE(class, name): for c++ classes.