Re: [ROOT] Question about TNtuple

From: Rene Brun (Rene.Brun@cern.ch)
Date: Fri Jan 10 2003 - 13:00:55 MET

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In reply to: suaide@physics.wayne.edu: "[ROOT] Question about TNtuple"
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Hi Alex,

Do:

TFile f("myfile.root");
TNtuple *ntuple = (TNtuple*)f.Get("ntuple name");
float x,y,z;
ntuple->SetBranchAddress("y",&y);
ntuple->GetEntry(342);
cout <<"y="<<y<endl;

Rene Brun


On Thu, 9 Jan 2003 suaide@physics.wayne.edu wrote:

> Hello all
> 
> I have a very basic question that I couldn't find help in the root
> documentation.
> 
> I have a TNtuple with 3 variables, say x,y and z. There are 1000 entries
> in this TNtuple. 
> 
> The question is: how can I get the value of y for the 342th entry, for 
> example? I am using root 3.03.09 on Linux RedHat 7.2
> 
> Regards
> 
> Alex
>

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