{
  // Dedomena Tash-Revma kai peiramatika sfalmata
  double V[12]={1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0};
  double I[12]={1.0, 2.0, 2.9, 4.0, 4.9, 5.9, 7.0, 8.0, 8.9, 10.0, 10.9, 11.9};
  double sfalma_V[12]={0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3, 0.3};
  double sfalma_I[12]={0.2, 0.2, 0.2, 0.2, 0.2, 0.2, 0.2, 0.2, 0.2, 0.2, 0.2, 0.2};
  TGraphErrors *gr=new TGraphErrors(12, V, I, sfalma_V, sfalma_I); // Orisnos toy grafimatos
  c1=new TCanvas("c1","Grafima", 1000, 800) ;
  c1->SetFillColor(42) ;
  c1->SetGrid() ;
  gr->SetTitle("Ohm's Law"); //Titlos graflmatos
  gr->GetXaxis()->SetTitle("V [Volts]"); //Monades ston x axona
  gr->GetYaxis()->SetTitle("I [mAmps]"); //Monades ston y axona
  gr->SetMarkerStyle(21) ;
  gr->SetMarkerSize(0.7) ;
  gr->SetMarkerColor(2) ;
  gr->SetLineColor(2) ;
  gr->Draw("AP"); // Sxediasnos grafimatos
}