/********************************************************/
/* This routine plots charge state shift versus         */
/* number of electrons which are not in close shell.    */
/********************************************************/

#include <TH1F.h>
#include <TF1.h>
#include <TLine.h>
#include <TCanvas.h>
#include <TLatex.h>
#include <TMath.h>

#define SHELLFAC 0.09147

using namespace std;

Double_t qshift(Double_t x) 
{
  return SHELLFAC*sin(2*TMath::Pi()*x);
}

void plot_qshift()
{
  TCanvas *c = new TCanvas("c","c");
  TF1 *f = new TF1("f","qshift(x)",0,1);
  f->SetTitle("Modélisation d'un remplissage de couches électroniques");
  f->GetXaxis()->SetTitle("Fraction d'électrons d'une couche non fermée");
  f->GetYaxis()->SetTitle("État de charge corrigé");
  f->Draw("");

  TLine *l = new TLine(0,0,1,0);
  l->SetLineStyle(3);
  l->Draw("same");

  TLatex Tl;
  Tl.SetTextColor(2);
  Tl.DrawLatex(0.5,0.085,"SHELLFAC=0.09147 C");

  c->SaveAs("qshift.eps");

}