JTestChi2R_1D.hh

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#ifndef __JCOMPAREHISTOGRAMS__JTESTCHI2R_1D__
#define __JCOMPAREHISTOGRAMS__JTESTCHI2R_1D__

#include <istream>
#include <ostream>
#include "JCompareHistograms/JTest_t.hh"
#include "JCompareHistograms/JTestChi2_t.hh"


/**
 * \author rgruiz
 */
namespace JCOMPAREHISTOGRAMS {

  /**
   * Implementation of the Chi2 test for 1D histograms.\n
   * This class is derived from the abstract class JTest_t(). For a general description of the implementation of this and other tests derived from JTest_t(), see its documentation.\n
   * The input parameter threshold(), is used to evaluate whether the test is passed or failed.\n
   * The evaluation is done by comparing the threshold() value with the result produced by JChi2Test(). The output of a Chi2 test is a p-value.\n 
   * The parameter threshold() should therefore be a real value between 0 and 1.
   */
  class JTestChi2R_1D: 
    public JTest_t , 
    public JTestChi2_t
  { 
  public:  

    /**
     * Default constructor.
     */
    JTestChi2R_1D() :
      JTest_t("Chi2R_1D", "chi2/NDF"),
      JTestChi2_t()
    {}

    /**
     * Read test parameters from input.
     *
     * \param  in            input stream
     * \return               input stream
     */
    std::istream& read(std::istream& in) override{ 
      return in >> threshold;
    };
    
    /**
     * Applies Chi2 test for two ROOT TH1 histograms.
     * 
     * \param o1 First histogram
     * \param o2 Second histogram
     */
    void test(TObject* o1, TObject* o2) override{

      using namespace std;
    
      if (!(dynamic_cast<TH2*>(o1) == NULL) || !(dynamic_cast<TH2*>(o2) == NULL)) {
        
        ERROR("For 2D histograms call JTestChi2_2D: " << o1->GetName() << std::endl);
    
      } else if (!(dynamic_cast<TH1*>(o1) == NULL) && !(dynamic_cast<TH1*>(o2) == NULL)) {
                  
        TH1D* h1 =  dynamic_cast<TH1D*>(o1);
        TH1D* h2 =  dynamic_cast<TH1D*>(o2);
  
        if(h1 -> GetNbinsX() != h2 -> GetNbinsX())
          ERROR("Histograms with different bining. The objects: " << h1 -> GetName() << " cannot be compared." << std::endl);

        JTestResult r = JChi2Test(h1, h2, threshold, testName, resultType, options);
     
        results.push_back(r);
      }
    };

    
  private:
    
    double threshold;                       //!< threshold p-value to decide if test is passed.
    const std::string options = "CHI2/NDF"; //!< options for the ROOT chi2 test.
  };
}

#endif