Example11.cxx

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// $Id$
//-----------------------------------------------------------------------
//       The GSI Online Offline Object Oriented (Go4) Project
//         Experiment Data Processing at EE department, GSI
//-----------------------------------------------------------------------
// Copyright (C) 2000- GSI Helmholtzzentrum fuer Schwerionenforschung GmbH
//                     Planckstr. 1, 64291 Darmstadt, Germany
// Contact:            http://go4.gsi.de
//-----------------------------------------------------------------------
// This software can be used under the license agreements as stated
// in Go4License.txt file which is part of the distribution.
//-----------------------------------------------------------------------

// Go4Fit Example N11


#ifndef __CINT__

#include "TH1.h"
#include "TFile.h"
#include "TApplication.h"

#include "TGo4Fitter.h"
#include "TGo4FitPeakFinder.h"

void Example11();

int main(int argc, char **argv)
{
   TApplication theApp("Application", nullptr, nullptr);

   Example11();

   theApp.Run();

   return 0;
}

#endif

// routine to read histogram from examples file
TH1D* GetHistogram(const char *HistogramName)
{
   TFile *f = TFile::Open("histograms.root");
   if (!f) return nullptr;
   TH1D *histo = nullptr;
   f->GetObject(HistogramName, histo);
   if (histo) histo->SetDirectory(nullptr);
   delete f;
   return histo;
}

void Example11()
{
// create fitter, select fit function and not add standard actions list
   TGo4Fitter fitter("Fitter", TGo4Fitter::ff_ML_Poisson, kTRUE);

// add histogram to fitter, which should be fitted
   fitter.AddH1("data1", GetHistogram("hDeg120_P_c"), kTRUE, 2200., 2900.);


// Add peak finder for data1, which not remove previous models and
// will use 1-order polynom for background
   TGo4FitPeakFinder* finder = new TGo4FitPeakFinder("Finder", "data1", kFALSE, 1);

// setup parameters for first peak finder.
// Here first - amplitude threshold relative to amplitude maximum,
// and minimum and maximum line width
   finder->SetupForFirst(.3, 5., 30.);

// add peak finder action at the beginning
   fitter.AddActionAt(finder, 0);

// perform all actions
// kTRUE means, that action is able to add/delete components to fitter
   fitter.DoActions(kTRUE);

// print models parameters in lines sorting
   fitter.Print("Lines");

// Draw data and model
   fitter.Draw("#data1");
}