void fit_waveform04(void)
{
//=========Macro generated from canvas: c1/c1
//=========  (Wed Dec 17 14:48:47 2014) by ROOT version5.34/19
   TCanvas *c1 = new TCanvas("c1", "c1",1505,246,779,672);

gROOT->Reset();
//TTree *Bfield = (TTree *) gROOT->FindObject("Bfield");
gStyle->SetPalette(1,0);
gStyle->SetOptStat(kTRUE);
gStyle->SetOptFit(kTRUE);
gStyle->SetOptFit(1111);
gStyle->SetPadRightMargin(0.15);
gStyle->SetPadLeftMargin(0.15);
gStyle->SetPadBottomMargin(0.15);
gStyle->SetFillColor(0);
//

   c1->Range(-21.79487,-16.8,106.4103,95.2);
   c1->SetFillColor(0);
   c1->SetBorderMode(0);
   c1->SetBorderSize(2);
   c1->SetLeftMargin(0.17);
   c1->SetRightMargin(0.05);
   c1->SetBottomMargin(0.15);
   c1->SetFrameBorderMode(0);
   c1->SetFrameBorderMode(0);
   
   TH1F *hist04 = new TH1F("hist04","Ch=38,10,14",100,0,100);
   hist04->SetBinContent(1,1);
   hist04->SetBinContent(2,3);
   hist04->SetBinContent(3,2);
   hist04->SetBinContent(4,4);
   hist04->SetBinContent(5,2);
   hist04->SetBinContent(6,2);
   hist04->SetBinContent(7,3);
   hist04->SetBinContent(8,2);
   hist04->SetBinContent(9,2);
   hist04->SetBinContent(11,2);
   hist04->SetBinContent(12,2);
   hist04->SetBinContent(13,2);
   hist04->SetBinContent(14,2);
   hist04->SetBinContent(15,2);
   hist04->SetBinContent(16,3);
   hist04->SetBinContent(17,3);
   hist04->SetBinContent(18,2);
   hist04->SetBinContent(19,3);
   hist04->SetBinContent(20,1);
   hist04->SetBinContent(22,1);
   hist04->SetBinContent(23,2);
   hist04->SetBinContent(24,2);
   hist04->SetBinContent(25,1);
   hist04->SetBinContent(26,4);
   hist04->SetBinContent(27,2);
   hist04->SetBinContent(28,2);
   hist04->SetBinContent(29,2);
   hist04->SetBinContent(30,1);
   hist04->SetBinContent(31,2);
   hist04->SetBinContent(32,2);
   hist04->SetBinContent(33,1);
   hist04->SetBinContent(34,1);
   hist04->SetBinContent(35,2);
   hist04->SetBinContent(36,10);
   hist04->SetBinContent(37,27);
   hist04->SetBinContent(38,32);
   hist04->SetBinContent(39,33);
   hist04->SetBinContent(40,33);
   hist04->SetBinContent(41,29);
   hist04->SetBinContent(42,25);
   hist04->SetBinContent(43,25);
   hist04->SetBinContent(44,24);
   hist04->SetBinContent(45,21);
   hist04->SetBinContent(46,19);
   hist04->SetBinContent(47,17);
   hist04->SetBinContent(48,14);
   hist04->SetBinContent(49,16);
   hist04->SetBinContent(50,12);
   hist04->SetBinContent(51,14);
   hist04->SetBinContent(52,12);
   hist04->SetBinContent(53,11);
   hist04->SetBinContent(54,9);
   hist04->SetBinContent(55,11);
   hist04->SetBinContent(56,10);
   hist04->SetBinContent(57,7);
   hist04->SetBinContent(58,7);
   hist04->SetBinContent(59,8);
   hist04->SetBinContent(60,6);
   hist04->SetBinContent(61,5);
   hist04->SetBinContent(62,8);
   hist04->SetBinContent(63,7);
   hist04->SetBinContent(64,5);
   hist04->SetBinContent(65,3);
   hist04->SetBinContent(66,2);
   hist04->SetBinContent(67,3);
   hist04->SetBinContent(68,2);
   hist04->SetBinContent(69,7);
   hist04->SetBinContent(70,2);
   hist04->SetBinContent(71,6);
   hist04->SetBinContent(72,4);
   hist04->SetBinContent(73,4);
   hist04->SetBinContent(74,1);
   hist04->SetBinContent(75,3);
   hist04->SetBinContent(76,4);
   hist04->SetBinContent(78,2);
   hist04->SetBinContent(79,2);
   hist04->SetBinContent(80,2);
   hist04->SetBinContent(81,1);
   hist04->SetBinContent(82,2);
   hist04->SetBinContent(83,3);
   hist04->SetBinContent(84,1);
   hist04->SetBinContent(85,1);
   hist04->SetBinContent(87,1);
   hist04->SetBinContent(88,2);
   hist04->SetBinContent(89,1);
   hist04->SetBinContent(90,1);
   hist04->SetBinContent(91,1);
   hist04->SetBinContent(95,2);
   hist04->SetBinContent(96,3);
   hist04->SetBinContent(97,4);
   hist04->SetBinContent(98,3);
   hist04->SetBinContent(99,2);
   hist04->SetBinContent(100,2);
   hist04->SetMaximum(84);
   hist04->SetEntries(1100);
   // hist04->SetStats(0);
   hist04->SetLineColor(2);
   hist04->GetXaxis()->SetTitle("sample   (4 ns)");
   hist04->GetXaxis()->SetNdivisions(505);
   hist04->GetXaxis()->SetLabelFont(42);
   hist04->GetXaxis()->SetLabelSize(0.07);
   hist04->GetXaxis()->SetTitleSize(0.07);
   hist04->GetXaxis()->SetTitleFont(42);
   hist04->GetYaxis()->SetTitle("ADC value");
   hist04->GetYaxis()->SetNdivisions(505);
   hist04->GetYaxis()->SetLabelFont(42);
   hist04->GetYaxis()->SetLabelSize(0.07);
   hist04->GetYaxis()->SetTitleSize(0.07);
   hist04->GetYaxis()->SetTitleOffset(1.2);
   hist04->GetYaxis()->SetTitleFont(42);
   hist04->GetZaxis()->SetLabelFont(42);
   hist04->GetZaxis()->SetLabelSize(0.07);
   hist04->GetZaxis()->SetTitleSize(0.07);
   hist04->GetZaxis()->SetTitleFont(42);
   hist04->Draw("");
   
   TPaveText *pt = new TPaveText(0,0.9018323,0.416129,0.995,"blNDC");
   pt->SetName("title");
   pt->SetBorderSize(0);
   pt->SetFillColor(0);
   pt->SetFillStyle(0);
   pt->SetTextFont(42);
   TText *text = pt->AddText("Ch=38,10,14");
   pt->Draw();
   c1->Modified();
   c1->cd();
   c1->SetSelected(c1);

   // define pulse function

   Double_t xmin=0;
   Double_t xmax=100;

   TF1 *pulse = new TF1("pulse_func",pulse_func,xmin,xmax,5);
   Double_t mu=1/8.;    // unis of 1/x
   Double_t sigma=5;     // units of x 
   Double_t gain=500;   
   Double_t t0=40;
   Double_t pedestal=2;
   pulse->SetParameters(mu,sigma,gain,t0,pedestal);
   pulse->SetParNames("mu","sigma","gain","t0","pedestal");
   // pulse->FixParameter(0,0.0787);
   // pulse->FixParameter(1,0.865);
  
   hist04->Fit(pulse);
   c1->SaveAs("fit_waveform04.pdf");

}
Double_t pulse_func (Double_t *x, Double_t *par) {

   Double_t mu=par[0];
   Double_t sigma=par[1];
   Double_t gain=par[2];
   Double_t t0=par[3];
   Double_t pedestal=par[4];
   Double_t x1=x[0]-t0;

   char string[256];

   Double_t func;
   Double_t amplitude;

   if (x1 < -20) {
           func = pedestal;
           }
   else if {

         Double_t arg = (mu*sigma*sigma-x1)/(sqrt(2)*sigma);
         Double_t arg2 = -mu*x1 +(mu*sigma)*(mu*sigma)/2;
         amplitude = (mu/2)* exp(arg2) *  TMath::Erfc(arg);
          func = gain * amplitude + pedestal;
  }
   
   /*sprintf (string,"x1=%f amplitude=%f mu=%f sigma=%f t0=%f pedestal=%f, func=%f\n",x1,amplitude,mu,sigma,pedestal,func);
   printf ("string=%s",string);*/

   return func;
}