Re: Paw ntuples & h2root
Rene Brun (Rene.Brun@cern.ch)
Wed, 21 May 1997 14:08:26 +0200
Isidro.Gonzalez.Caballero@cern.ch wrote:
>
> Hi:
> I've been using root utility h2root to
> convert a paw ntuple to a root TTree. There are
> serveral variables in my ntuple of the form
> P[Ntracks], Theta[Ntracks],... The question is
> how could I access and maybe plot a histogram for
> P[1], or Theta[4] for example?
>
Just do for example:
Root > ntuple.Draw("Theta[4]","Ntracks>4");
If you do:
Root > ntuple.Draw("Theta");
then, Root will histogram all Theta for all tracks.
Be careful, that numbering in Root always starts at 0.
Theta[0] is the Theta for the first track.
Rene Brun