{
#include <iostream>
#include <math.h>

// Electric field calculation,  Taka Kondo (KEK) 2009.11.27
// unit: nsec, cm, sec, K, 
gROOT->LoadMacro("AtlasUtils.C");
ATLAS->SetPadRightMargin(0.20);
c1 = new TCanvas("c1","A Simple Graph with error bars",0,0,700,500);
c1->GetFrame()->SetBorderSize(12);
//
TH2F *hE2 = new TH2F("hE2","Electric field2",80,0.,400.,114,0.,285.); 
 
double x,y,P;
for (int k=0; k<80; k++){
//for (int k=0; k<1; k++){
for (int i=0; i<117; i++){
x = 5.*(k+0.5);
y = 2.5*(i + 0.5);
P=Ramo_potential( x/10000., y/10000.);
if(i==0) cout<<"x,y,P="<<x<<" "<<y<<" "<<P<<endl;
hE2->Fill(x,y,P);
}
}

hE2->SetXTitle("X [#mum]");
hE2->GetXaxis()->SetTitleOffset(1.0);
hE2->SetYTitle("Y [#mum]");
hE2->GetYaxis()->SetTitleOffset(1.2);
gStyle->SetPalette(1);
hE2->Draw("COLZ");
//
TLatex *t=new TLatex(490.,60.,"Weighting Potential"); 
t->SetTextAngle(90.);
t->SetTextSize(0.05);
t->Draw();
//
zb=new TBox(30.,285.,50., 287.); zb->SetFillColor(1); zb->Draw();
zb=new TBox(110.,285.,130., 287.); zb->SetFillColor(1); zb->Draw();
zb=new TBox(190.,285.,210., 287.); zb->SetFillColor(1); zb->Draw();
zb=new TBox(270.,285.,290., 287.); zb->SetFillColor(1); zb->Draw();
zb=new TBox(350.,285.,370., 287.); zb->SetFillColor(1); zb->Draw();
c1->Print("P_2D.pdf");
}