cannot access subjets in code

[Nikolay Kolev]

I am using Delphes 3.3.2 and need subjet information, e.g.
Jet_TrimmedP4[5][kMaxJet]. If I open the root file in TBrowser,
I get the graph with 5 times as many entries as the number of
jets. In code, I get all zeroes, e.g.:

for (int i = 0; i < Jet_; i++)
{

cout << (Jet_TrimmedP4[0][i])[0] << endl;
.....

}

or:

cout << (Jet_TrimmedP4[0][i]).Pt() << endl;

Wht am I doing wrong?

[Michele Selvaggi]

Do the following:

for(i = 0; i < branchJet->GetEntriesFast(); ++i)
{
     jet = (Jet*) branchJet->At(i);
     TLorentzVector p[5];
 
     for( Int_t j = 0; j < 5; j++)
     {
        p[j] = jet->TrimmedP4[j];
        cout<<p[j].Pt()<<endl;
       ...   
      }
}

[Nikolay Kolev]

Thank you for the quick reply. So I need access to the jets branch. I tried several things and can't get it right, e.g.:

TBranch *jet = fChain->GetBranch("Jet");
for (int i = 0; i < jet->GetEntriesFast(); i++)
{ ........

Error: Can't call TBranch::GetEntriesFast () in current scope.

So I guess my question is: what is branchJet in the context of the class that MakeClass makes?

[Michele Selvaggi]

Have a look at examples/Example3.C

[Nikolay Kolev]

Thanks.

I was trying to keep using MakeClass; so I rewrote the analysis code as the delphes examples suggest and everything is working now; I have access to the subjets. As a side effect since it is now a regular c++ program using root and delphes libraries and doesn't run under root, it is going orders of magnitude faster.

I guess it is always worth doing things properly.

Thank you for the help.

Nikolay