#include <iostream>

#include "TGraph2D.h"
#include "TFile.h"
#include "TCanvas.h"
#include "TTree.h"
#include "TString.h"

using namespace std;

//======================================================================

void tester( const TString& fname )
{

  TGraph2D *gr = new TGraph2D();

  gr->SetName("gr");

  TFile *f = new TFile(fname);
  TTree *t = (TTree *) f->Get("limit");

  if (!t) { 
    std::cerr<<"TFile "<<f->GetName()<<" does not contain the tree"<<std::endl;
    return;
  }
  cout << fname << " has tree with " << t->GetEntries() << " entries." << endl;

  Float_t x,y,z;

  t->SetBranchAddress("lZ", &x);
  t->SetBranchAddress("dkg", &y);
  t->SetBranchAddress("deltaNLL", &z);

  for (size_t j = 0, n = t->GetEntries(); j < n; ++j) {
    t->GetEntry(j);
    gr->SetPoint(j,x,y,z);
  } // tree entry loop

  f->Close();
  delete f;

  cout << endl;

  double *vx = gr->GetX();
  double *vy = gr->GetY();
  double *vz = gr->GetZ();

  for(int i=0; i<gr->GetN(); i++)
    printf ("%d\t%f\t%f\t%f\n",i,vx[i],vy[i],vz[i]);
    
  TCanvas *canv = new TCanvas("tester","tester",500,500);
  cout << gr->GetN()<<" points. " <<endl;
  gr->Draw("SURF3"); // "TRI");
}