How to read this TVector3?

Dear ROOT expert:

Recently I got a problem in reading a TVector3 from a ROOT file, the readout values are always 0.

I put it on /tmp/qing/qing.tar.gz on, after untar it, you can run .x genbamu3.C++. then you will see that those values in fgiga->fCandidates_fPosition are always 0, but when opening it with TBrower b in root directly, they are not 0,

reco_BA_k2pi_pimumu_5k-ios.root -> GigaTracker -> Reco -> TRecoVEvent -> fCandidates -> fCandidates.fPosition[3] ,

The red exclamation point on the leaf in the TBrower are executable methods available when the dictionary of the class is loaded, usually it can be solved by adding SetMakeClass(1), but I see it’s already defined in those head files,

[root@ppepc176 rootreco2]# grep SetMakeClass *
gen.h: fChain->SetMakeClass(1);
giga.h: fChain->SetMakeClass(1);
gigatest.h: fChain->SetMakeClass(1);
iostest.h: fChain->SetMakeClass(1);
irc.h: fChain->SetMakeClass(1);
lav.h: fChain->SetMakeClass(1);
lkr.h: fChain->SetMakeClass(1);
muv3.h: fChain->SetMakeClass(1);
sac.h: fChain->SetMakeClass(1);
spec.h: fChain->SetMakeClass(1);
temp.h: fChain->SetMakeClass(1);

Any idea on how to read out this TVector3?


Dear Gang,

Sorry for the late reply.
Is this a TTree with TVector3 or just TVector3 stored in the file?
Sorry, can you put again qing.tar.gz somewhere? It was removed from .

G Ganis