#include "TFile.h"
#include "TTree.h"
#include "TH1D.h"
#include "TF1.h"
#include "TRandom3.h"
void troubleshootFillRandom()
{
  TH1D *templateHist = new TH1D("templateHist", "", 20, -10, 10);

  TF1* myGaus = new TF1("myGaus", "gaus", -10, 10);
  
  myGaus->SetParameter(0, 1);
  myGaus->SetParameter(1, 0);
  myGaus->SetParameter(2, 3);

  templateHist->FillRandom("myGaus", 10000);

  //templateHist->Draw();

  TF1 *unif = new TF1("unif", "1.0", -10, 10);

  Double_t chi2 = 0;

  TH1D *hist1 = new TH1D("hist1", "", 20, -10, 10);
  TH1D *hist2 = new TH1D("hist2", "", 20, -10, 10);

  // hist1->Sumw2();
  // hist2->Sumw2();

  // TH1D *ratio = (TH1D*)hist1->Clone("ratio");
  
  TFile *fileOut = new TFile("troubleshootFillRandom.root", "RECREATE");
  TTree *treeOut = new TTree("results", "");
  
  treeOut->Branch("chi2", &chi2);

  for(Int_t i=0; i<=100000; i++)
  {
    gRandom->SetSeed(0);
    hist1->FillRandom(templateHist, 10000);
    gRandom->SetSeed(0);
    hist2->FillRandom(templateHist, 10000);

    // ratio->Divide(hist1, hist2, 1.0/hist1->Integral(), 1.0/hist2->Integral());

    // chi2 = ratio->Chisquare(unif);
    chi2 = hist1->Chi2Test(hist2, "UU CHI2");
    treeOut->Fill();
  }
  fileOut->Write();
  fileOut->Close();
}