Hi Avi,
As indicated by the error messages, your library with the classes Neutron,
Tracks and Bunch is missing. Did you forget to load it ?
With the new branch style introduced in 3.01, one should be able to copy/select
a Tree without having the original classes.
Rene Brun
Avi Malki wrote:
>
> hi rooters,
>
> We would like to consider reducing the data and select events with some
> criteria such as 3 tracks (in event branch) and one negative particle (in
> tracks branch) for example.
>
> The program below create a new tree with number of tracks equal 3
> for example. The problem is that only 'event' is created the other
> Branches (they are under event branch): Neutron, Tracks and Bunch
> are filled with zeros for all variables.
>
> Can someone please give us advise how to overcome this problem?
>
> Best regards
> avi.
>
> {
> gROOT->Reset();
>
> gSystem->Load("/usr/local/root/test/libEvent.so");
>
> TFile f("../DATA/tf8826.root");
> TTree *T = (TTree*)f.Get("T");
>
> Event *event = new Event();
>
> T->SetBranchAddress("event",&event);
>
> TFile f2("New.root","recreate");
> TTree *T2 = T->CopyTree("Ntrack==3");
>
> T2->Write();
> }
>
> The problem:
>
> root [0]
> Processing tree_copy.c...
> Warning in <TBranchClones::Streamer>: Unknow class: Neutron. Cannot read BranchClones: fNeut
> Warning in <TBranchClones::Streamer>: Unknow class: Bunch. Cannot read BranchClones: fBn
> Warning in <TBranchClones::Streamer>: Unknow class: Neutron. Cannot read BranchClones: fNeut
> Warning in <TBranchClones::Streamer>: Unknow class: Bunch. Cannot read BranchClones: fBn
> root [1] .q
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