Re: Problem with CloneTree

Hi Francesco,

Replace the line

    TTree *newtree = oldtree->CloneTree();

by

    TTree *newtree = oldtree->CloneTree(0); //only copy the Tree header , not the data

Rene

On 16/09/2011 09:33, perfetto_at_na.infn.it wrote:
> Hi Rooters,
>
> I have the following problem (I use root 5.30/01 on osx):
>
> Using MakeClass I have had 2 files, .C and a .h.
> Now in the .C within the Loop() function, I open a root file, get the
> tree, open a new file and in this new file I clone it.
> After I create other variables that I would add to this new file; but
> after the Fill() command, my new tree has the double of entries.
> Where do I do a mistake ?
>
> For clarity I attach a piece of code:
>
>
> void analysis_fra::Loop()
> {
> if (fChain == 0) return;
>
> Long64_t nentries = fChain->GetEntriesFast();
>
> Long64_t nbytes = 0, nb = 0;
>
> Double_t sum_min;
> Bool_t is_cut;
> Int_t n_pmt;
>
> TFile *oldfile = new TFile("run3008.root");<------- In this file there
> are 23760 entries
> TTree *oldtree = (TTree*) oldfile->Get("Events");
> TFile *newfile = new TFile("analisi.root","recreate");
> TTree *newtree = oldtree->CloneTree();
>
> // Some variables that I would add to newtree
> newtree->Branch("sum_min",&sum_min, "sum_min/D");
> newtree->Branch("run_id",&run_id, "run_id/I");
> newtree->Branch("is_cut",&is_cut, "is_cut/B");
> newtree->Branch("n_pmt",&n_pmt, "n_pmt/I");
> ....
>
> for (Long64_t jentry=0; jentry<nentries;jentry++) {
> ...
> sum_min = 0.;
> n_pmt = 0;
> for ( Int_t i = 0; i< 35; i++ ) {
> if (channels_npulses[i]> 0) {
> is_cut = kTRUE;
> sum_min = sum_min - channels_minimum[i] + channels_baseline_mean[i]; n_pmt
> = n_pmt + 1;
> ...
> }
> }
>
> newtree->Fill();<------- If I comment this line I have the correct
> entries 23760, but obviously I don't have the new variables in the tree. }
> newtree->Write();
> newfile->Write();
> newfile->Close();
> delete oldfile;
> delete newfile;
> }
> When open newtree this has 47520 entries.
>
> Thank in advance
> Francesco.
>
>
>
Received on Fri Sep 16 2011 - 10:09:30 CEST