void macro(){

    auto c1 = new TCanvas();
    c1->Divide(2,1);

    auto graphT = new TGraph("fasi.dat", "%lg %lg %*lg");

    auto graphTE = new TGraphErrors("fasi.dat","%lg %lg %lg");

    auto fitT = new TF1("TF1", "[0]*180*TMath::ATan(1/([1]*x*TMath::Pi()*2))/Tmath::Pi()", 4000, 6000);
    fitT->SetParameters(1,1);

    c1->cd(1);
    graphT->Draw();
    graphT->Fit(fitT);

    std::cout << "\n \n \n";

    c1->cd(2);
    graphTE->Draw();
    graphTE->Fit(fitT);

    c1->Print("prova.pdf", ".pdf");
}