////////////////////////////////////////////////////////////////////////
//
// RunGuru.cpp, written by Gavin Hesketh (ghesketh@fnal.gov), Feb 2007
//
// A c++ interface to the fortran functions of the guru package
// This code reads in plots from a root file, and calls the unfolding.
//
// For more information on this code: http://www-d0.fnal.gov/~ghesketh/unfolding/
// GURU algorithm and fortran code written by 
//            Vato Kartvelishvili (v.kartvelishvili@lancaster.ac.uk)
// For more information on GURU, see Arxiv hep-ph/9509307
//
//
// To run, you need at least these two plots:
//   true_mat_plot = migration matrix
//   bdata_plot    = data distribution
//
// You can also provide the following:
//   prob_mat_plot = migration matrix, probability form:
//   xini_plot     = truth distribution used to generate the migration matrix
//   xtst_plot     = the actual MC trugh shape:
//   btst_plot     = the MC measured (reco) shape:
//  
// Note: if these plots are not provided (set to zero), they are derived as follows:
//   xini = Y axis projection of true_mat_plot (excluding under/overflows)
//   xtst = Y axis projection of true_mat_plot (excluding under/overflows)
//   btst = X axis projection of true_mat_plot (excluding under/overflows)
//   prob_mat_plot = true_mat_plot / xini
//
//
// Change log:
// 13th Feb 2007: original version.
//
////////////////////////////////////////////////////////////////////////

#include <iostream>
#include <iomanip>
#include "TFile.h"
#include "TH2.h"
#include "TH1.h"

#include "guru_interface.cpp"



main() {

  //First, some declarations:

  //These are the two basic plots you must have:
  TH2 *true_mat_plot=0; //migration matrix
  TH1 *bdata_plot=0;    //data distribution

  //additional plots, load in if available, otherwise leave as 0;
  TH2 *prob_mat_plot = 0; //migration matrix, probability form:
  TH1 *xini_plot = 0; //truth distribution used to generate the migration matrix
  TH1 *xtst_plot = 0;  //the actual MC trugh shape:
  TH1 *btst_plot = 0;   //the MC measured (reco) shape:
  



 

  //-----------------------------------------------------------
  // First, call the unfolding on the example:
  // final argument set up the example (default = false)

  RunGuru("output_example.root",0,0,0,0,0,0, true);






  //-----------------------------------------------------------
  //Now, read in the basic plots from the output, and unfold again

  // Always zero the plots before starting! 
  prob_mat_plot = 0;
  xini_plot = 0;
  xtst_plot = 0;
  btst_plot = 0;
  true_mat_plot=0; 
  bdata_plot=0;

  //open the input file:
  TFile *mc_input = new TFile("output_example.root", "READ");
  mc_input->cd();

  //We need at least these two plots to run:
  //the migration matrix from MC:
  true_mat_plot = (TH2*)gDirectory->Get("02_Tru_Mat_APRO");

  //the data plot:
  bdata_plot = (TH1*)gDirectory->Get("06_bdata");

  // Load these plots if we have them:
  prob_mat_plot = (TH2*)gDirectory->Get("01_Prob_Mat_APRO");
  xini_plot = (TH1*)gDirectory->Get("03_xini");
  xtst_plot = (TH1*)gDirectory->Get("04_xtst");
  btst_plot = (TH1*)gDirectory->Get("05_btst");


  // call the unfolding: 
  RunGuru("output_guru.root", bdata_plot, true_mat_plot, xini_plot, xtst_plot);  
 





 
  //if you only have the two basic plots, can call like:
  //note, the chi^2 table won't make any sense, as you don't provide xtst!
  string output_file_name = "output_guru_2.root";
  RunGuru(output_file_name, bdata_plot, true_mat_plot);




 

  return 0;
  
}