//basic C++ commands
#include <vector>
#include <iostream>
using namespace std;

// ROOT header
#include "Riostream.h"
#include "TROOT.h"
#include "TBuffer.h"
#include "TApplication.h"
#include "TCanvas.h"
#include "TStyle.h"
#include "TLegend.h"
#include "TLatex.h"
#include "TH1.h"
#include "TH2.h"
#include "TF1.h"
#include "TH1D.h"
#include "TGraph.h"
#include "TGraphErrors.h"
#include "TMarker.h"
#include "TString.h"
#include "TFile.h"
#include "TMath.h"
#include "TVector3.h"
#include "TLine.h"
#include "TBranch.h"
#include "TTree.h"
#include "TPad.h"
#include "TChain.h"
#include "TSystem.h"
#include "TRandom.h"

//fitfunction algorithm
double fitFunction(double *x, double *par)
{
 if (x[0] <= par[1] ) { //for four/second fit function .79, .791
      TF1::RejectPoint();
      return 0;
   }
   return (par[0]*(x[0]-par[1])*TMath::Exp(-(x[0]-par[1])*(x[0]-par[1])/(2*par[2]*par[2])));
}


void run() {

double a;
double tzero;
//TH1F *h1 = new TH1F("h1","h11", 24, 0, 24);
TH1F *htzero = new TH1F("htzero","htzero", 1000, -7, 12);
TH1F *hg = new TH1F("hg","hg", 100, 0, 3);
TH2F *hgall = new TH2F("hgall","hgall", 100, 0, 4, 100, 0, 4);
TF1 *f1 = new TF1("f1","(x-[0])*TMath::Exp(-((x-[0])*(x-[0]))/(2*[1]*[1]))",0,24);
TF1 *fitFcn = new TF1("fitFcn",fitFunction, 0, 24, 3);
TCanvas *c6 = new TCanvas("c6", "Z Inv Mass from Different Tags /2 Binning", 1500, 900);
for (int k=0; k<20000; k++) { 
	TH1F *h1 = new TH1F("h1","h11", 24, 0, 24);
	double start=-2;
	double final=10;
	double g=start + (gRandom->Rndm() * (final-start));
	double b=2.5;
	hg->Fill(g);
	f1->SetParameter(0,g); f1->SetParameter(1, b);
	for (int i=0; i<1000; i++) {
		a=f1->GetRandom();
		if (a>g)
			h1->Fill(a);
	}
	h1->Scale(11);
	fitFcn->SetParameter(0,h1->GetMaximum());
	fitFcn->SetParameter(1,1.7);
	fitFcn->SetParameter(2,2.5);
	h1->Fit("fitFcn","Q","RNO");
        tzero=fitFcn->GetParameter(1);
	htzero->Fill(tzero);
	hgall->Fill(g,tzero);
        h1->Delete();

}
htzero->Draw();
// 2D

TCanvas *c5 = new TCanvas("c5", "nt Tags /2 Binning", 1500, 900);
gStyle->SetPalette(1);
hgall->Draw("COLZ");
hgall->SetXTitle("g");
hgall->SetYTitle("g from fit");

}