{

  int r,z,phi;
  float bx, by, bz;
  int i;
  int rMin, rMax;
  int zMin, zMax;
  int phiMin, phiMax;


  // arbitrary startup values fir finding Min,Max in the loop
  rMax = 100.0;
  zMax = 0.0;
  phiMax = 30.0;

  rMin =  100.0;
  zMin =  0.0;
  phiMin = 30.0;


  TH2F *h7  = new TH2F("Phi=7deg", "Phi=7deg",  150,0,300,230,-230,230);
  TH2F *h15 = new TH2F("Phi=15deg","Phi=15deg",150,0,300,230,-230,230);
  TH2F *h30 = new TH2F("Phi=30deg","Phi=30deg",150,0,300,230,-230,230);
  TH2F *h37 = new TH2F("Phi=37deg","Phi=37deg",150,0,300,230,-230,230);

  //FILE *fp = fopen("FieldMap_Falk_August2003.dat","r");
  //FILE *fp = fopen("FieldMap_Falk_June2003.dat","r");  // different data structure !!!
  //FILE *fp = fopen("q_weak_mag_field_map.dat","r");
  FILE *fp = fopen("old_field_map.dat","r");

  while( fscanf(fp,"%d%d%d",&r, &z, &phi)==3){
    printf( "%d %d %d \n",r,z,phi);
    fscanf(fp,"%f%f%f",&bx, &by, &bz);
    //if (i%10000==0) printf("%d %f ",i,bz);
    //if (i%100000==0) printf("\n");

    i++;

    if (r > rMax) rMax = r;
    if (r < rMin) rMin = r;
    if (z > zMax) zMax = z;
    if (z < zMin) zMin = z;
    if (phi > phiMax) phiMax = phi;
    if (phi < phiMin) phiMin = phi;
  
    if (phi ==  7)  h7 ->Fill(r,z,bz);
    if (phi == 15) h15->Fill(r,z,bz);
    if (phi == 30) h30->Fill(r,z,bz);
    if (phi == 37) h37->Fill(r,z,bz);
 
  }
  
  printf("\n x %d %d    y %d %d    z %d %d \n", rMax, rMin, zMax, zMin, phiMax, phiMin);
 
  TCanvas c1;
  TCanvas c2;
  TCanvas c3;
  TCanvas c4;

  c1->cd();
  c1->Clear();
  h7->Draw("surf1");
  c1->Update();

  c2->cd();
  c2->Clear();
  h15->Draw("surf1");
  c2->Update();

  c3->cd();
  c3->Clear();
  h30->Draw("surf1");
  c3->Update();

  c4->cd();
  c4->Clear();
  h37->Draw("surf1");
  c4->Update();

}