test/TestTFndFitter.C

//                                             //
// This macro is an example for using the      //
//  most important facilities provided by the  //
//  FIN_AN namespace:                          //
//    (see $FROOTSYS/ANALYSIS/FIN_AN.h)        //
//                                             //
// Peak fitting is supported by TFndFitter     //
//    (see $FROOTSYS/ANALYSIS/TFndFitter.h)    //
//                                             //

#include "Riostream.h"
#include "TSystem.h"
#include "TStyle.h"
#include "TCanvas.h"
#include "TH1F.h"
#include "TRandom.h"
#include "TThread.h"

#include "TFndFitter.h"

#include "HistogramCreators.C"


void TestTFndFitter(){
  gStyle->SetOptStat(1001111);

  // --- peaks simulation
  Int_t n_simul_peaks=7;
  Double_t simul_sigma=0.01;
  Double_t sig_noise_ratio=2.;
     
  Bool_t eval_background = kTRUE;
  Int_t n_iter_background = 50;
  Double_t resolution_factor = 1.5;

  // --- peaks evaluation
  Int_t n_max_expected_peaks = 10;
  Double_t expected_sigma = 0.015;
  Double_t sigma_maxerr=0.005;
  Double_t peaks_threshold = 0.3;

  TH1F *start_his = BuildExampleHistogram(n_simul_peaks,simul_sigma,sig_noise_ratio,kTRUE);
  
  //  TH1F *start_his = new TH1F("starthis","starthis",3000,0,1);
  //   for(Int_t i=0;i<20000;i++)  start_his->Fill(gRandom->Gaus(.5,.02) );
  
  
  // --- evaluate background
  TH1F *fBckHis = 0;
  if(eval_background) fBckHis = EvalBackground(start_his,n_max_expected_peaks,n_iter_background);

  // --- check peaks before subtracting background
  TSpectrum *spec = FindPeaks(start_his,n_max_expected_peaks,expected_sigma,peaks_threshold,resolution_factor,"");
  UpdateDisplay(start_his,fBckHis);
  PrintFoundPeaks(spec);
  //  

  // --- subtract background (if required)
  TH1F *clean_his = (TH1F*)(start_his->Clone("CloneHis") );
  clean_his->SetTitle("Clean histogram (simple clone)");
  if(fBckHis){
    Printf("Now evaluating clean histogram (subtracting background)...");
    clean_his->SetName("CleanHis");
    clean_his->SetTitle("Clean histogram");
    clean_his->Add(fBckHis,-1);
    Printf("...clean histogram evaluated");
  }
  //  

  // --- check peaks after subtracting background
  spec = FindPeaks(clean_his,n_max_expected_peaks,expected_sigma,peaks_threshold,resolution_factor,"");
  UpdateDisplay(start_his,fBckHis,clean_his);

  TFndFitter *fndfit = new TFndFitter();
  fndfit->SetCurrentHistogram(clean_his);
  fndfit->SetCurrentSpectrum(spec);
  fndfit->SetResolutionFactor(resolution_factor);
  //
  fndfit->FitAllPeaks_GausYield(expected_sigma,sigma_maxerr);
  //  fndfit->FitSinglePeak_GausYield(2,expected_sigma,sigma_maxerr);
  fndfit->PrintFittedPeaks_GausYield();
  Printf("...peaks fit completed... :)");

  // --- now find a specific peak and get information:
  TF1 *foundpeak = fndfit->LocateFittedPeak_GausYield(0.4,0.6);

  Printf("Peak found: %s",foundpeak->GetName());
}

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