Read TVectorD from TTree

ROOT
1

Hi,

I know that this probably a really stupid question, but how can I read back in compiled macro a TVectorD from a TTree. I produced the tree with the TTreeSRedirector (variable: fpcstream),

TVectorD dcaTrack(3); TVectorD pTTrack(3);
… // filling of the dcaTrack(3) and pTTrack(3)

if (fpcstream){ (*fpcstream)<<"Vertices" << "dcaTrack.=" << &dcaTrack << "pTTrack.="<< &pTTrack << "\n"; }

This worked fine. Now I would like to read this tree, however I somehow screw it up and it doesn’t work:

   TTree *Vertices = (TTree*)gDirectory->Get("Vertices");
   TVectorT<double> 		dcaTrack;
   TVectorT<double>	 	pTTrack;

   Vertices->SetBranchAddress("dcaTrack.",&dcaTrack);
   Vertices->SetBranchAddress("pTTrack.",&pTTrack);

This code piece was mainly generated by Vertices->MakeCode(). What am I doing wrong?

Regards,
Fredi

2

Hi Fredi,

MakeCode (and MakeClass) set the TTree in mode that prevents reading object. To read the object, you need to comment out of the line fChain->SetMakeClass(1).

Cheers,
Philippe.