Re: TTree with Folders

You get in the Tree what you put in the folder! You create a RVertex with your default constructor and add it to the folder, then you create another RVertex with the argument 100 but DO NOT PUT it in the folder!

Rene Brun

Stefano Dusini wrote:
> Hello,
>
> I am creating a Tree with a Branch from a Folder according to the
> following scheme:
>
> TFile *fOut = TFile::Open("testVertex.root","recreate");
> TTree *outTree = new TTree("TreeVX","Vertex output");
>
> //create the folders
> TFolder *m_topFoldVX = gROOT->GetRootFolder ()->AddFolder ("topFoldVX",
> "Top Level Folders");
> gROOT->GetListOfBrowsables()->Add (m_topFoldVX, "topFoldVX");
> TFolder *m_vxFold = m_topFoldVX->AddFolder("Raw","raw data");
>
> //create the objects. Both are public TNamed
> RVertex *vertex = new RVertex();
> vertex->SetName("Vertex");
> RTrack *track = new RTrack();
>
> //Add the object to the folder
> m_vxFold->Add(vertex);
>
> //create the branch from the folder
> outTree->Branch(m_topFoldVX->FindFullPathName(m_vxFold->GetName())+1)
>
> //Fill the objects
> RVertex *v1 = new RVertex(100);
> RTrack *t1 = new RTrack(11);
>
> // The track t1 is added to a TObjArray which is a private member of
> // the RVertex class
> v1->AddTrack(t1);
> REMULTrack *t2 = new RTrack(12);
> v1->AddTrack(t2);
>
> // Fill the tree
> vertex = v1;
> outTree->Fill();
>
> //new vertex
> RVertex *v2 = new RVertex(101);
> RTrack *t3 = new RTrack(21);
> v2->AddTrack(t3);
>
> vertex = v2;
> outTree->Fill();
>
> fOut->Write();
> fOut->Close();
>
> This code create a tree with two entries but with the RVertex class
> which has the values given by the default constructor and not the
> values given in the code (100,101) and in particular the TObjArray
> containing the tracks is always empty.
>
> But if instead of creating the Branch from the folder I do it explicitly
>
> TFile *fOut = TFile::Open("testVertex.root","recreate");
> TTree *outTree = new TTree("TreeVX","Vertex output");
>
> //create the objects
> RVertex *vertex = new RVertex();
> vertex->SetName("Vertex");
> RTrack *track = new RTrack();
>
> outTree->Branch("vertexBranch", "REMULVertex",&vertex,16000,2);
>
> //Fill the objects
> RVertex *v1 = new RVertex(100);
> RTrack *t1 = new RTrack(11);
>
> // The track t1 is added to a TObjArray which is a private member of
> // the RVertex class
> v1->AddTrack(t1);
> REMULTrack *t2 = new RTrack(12);
> v1->AddTrack(t2);
>
> // Fill the tree
> vertex = v1;
> outTree->Fill();
>
> //new vertex
> RVertex *v2 = new RVertex(101);
> RTrack *t3 = new RTrack(21);
> v2->AddTrack(t3);
>
> vertex = v2;
> outTree->Fill();
>
> fOut->Write();
> fOut->Close();
>
> the tree is correctly filled with the correct objects.
>
> Can you please tell me what is wrong with the first example.
>
> Thanks a lot for your help.
> Stefano
>
Received on Tue Oct 20 2009 - 07:55:26 CEST