TH1F *distribution = new TH1F("distribution", "Angular distribution", 10, -1 , 1 );
    distribution->SetBinContent(1,20.);
    distribution->SetBinContent(2,16.);
    distribution->SetBinContent(3,11.);
    distribution->SetBinContent(4,8.);
    distribution->SetBinContent(5,5.);
    distribution->SetBinContent(6,4.);
    distribution->SetBinContent(7,3.);
    distribution->SetBinContent(8,2.5);
    distribution->SetBinContent(9,2.);
    distribution->SetBinContent(10,1.);

    TH1F *distribution2 = new TH1F("distribution2", "Angular distribution2", 10, -1 , 1 );
    distribution2->SetBinContent(1,10.);
    distribution2->SetBinContent(2,11.);
    distribution2->SetBinContent(3,12.);
    distribution2->SetBinContent(4,13);
    distribution2->SetBinContent(5,14);
    distribution2->SetBinContent(6,17);
    distribution2->SetBinContent(7,30);
    distribution2->SetBinContent(8,40);
    distribution2->SetBinContent(9,45);
    distribution2->SetBinContent(10,60);
    
    TH1F *distribution3 = new TH1F("distribution3", "Angular distribution2", 10, -1 , 1 );
    distribution3->SetBinContent(1,1.);
    distribution3->SetBinContent(2,1.);
    distribution3->SetBinContent(3,1.);
    distribution3->SetBinContent(4,1);
    distribution3->SetBinContent(5,1);
    distribution3->SetBinContent(6,1);
    distribution3->SetBinContent(7,3);
    distribution3->SetBinContent(8,4);
    distribution3->SetBinContent(9,4);
    distribution3->SetBinContent(10,6);

    model->AddHistogram(distribution,"if (_y < 1.601) _f = Eval(_x);");
    model->AddHistogram(distribution2,"if (_y > 1.600 && _y < 1.801) _f = Eval(_x);");
    model->AddHistogram(distribution3,"if (_y > 1.800) _f = Eval(_x);");