even_odd_coll.cpp

{
    TFile * file1_ = new TFile("./build/Data/test_colliding_inspect_even_0.root");
    TFile * file2_ = new TFile("./build/Data/test_colliding_inspect_odd_0.root");

    TTree * tree1_ = (TTree*) file1_->Get("TT_0");
    tree1_->SetName("tree1_");
    TTree * tree2_ = (TTree*) file2_->Get("TT_0");
    tree2_->SetName("tree2_");

    tree1_->AddFriend("tree2_");

    TCanvas * c1 = new TCanvas("c1", "c1", 600, 400);
    TPad    * p1 = new TPad("p1", "p1", 0.0, 0.3, 1.0, 1.0);
    TPad    * p2 = new TPad("p2", "p2", 0.0, 0.0, 1.0, 0.3);

    tree1_->Draw("imp:SAngle1", "", "goff");
    TGraph  * g1 = new TGraph(tree1_->GetSelectedRows(), tree1_->GetV1(),  tree1_->GetV2() );
    g1->SetMarkerStyle(20);
    g1->SetMarkerSize(0.8);
    g1->SetName("g1");
    

    tree2_->Draw("imp:SAngle1", "", "goff");
    TGraph  * g2 = new TGraph(tree2_->GetSelectedRows(), tree2_->GetV1(),  tree2_->GetV2() );
    g2->SetMarkerStyle(20);
    g2->SetMarkerSize(0.8);
    g2->SetName("g2");

    tree1_->Draw("imp:(SAngle1-tree2_.SAngle1)", "", "goff");
    TGraph  * g3 = new TGraph(tree1_->GetSelectedRows(), tree1_->GetV1(),  tree1_->GetV2() );
    g3->SetMarkerStyle(20);
    g3->SetMarkerSize(0.8);

    TMultiGraph * mg = new TMultiGraph();
    mg->Add(g1);
    mg->Add(g2);
    // mg->Add(g3);
    p1->Draw();
    p1->cd();
    mg->Draw("AP");
    c1->cd();
    p2->Draw();
    p2->cd();
    g3->Draw("AP");

    



    // tree1_->AddFriend("tree2_");
}