Re: [ROOT] problem with TTree::Print in 3.10/02

From: Rene Brun (Rene.Brun@cern.ch)
Date: Wed Apr 14 2004 - 12:18:29 MEST


Hi Robert,

The keywords "left" and "right" are manipulators used by C++ iostream
see: http://www.cplusplus.com/ref/iostream/ios_base/_internal_left_right.html

Rene Brun

Robert Michaels wrote:
> 
> Using ROOT 3.10/02 compiled with gcc 3.2.3 on a RHEL 3WS.
> The following example illustrates my problem.  It is minor
> but I am wondering why this occured for this newer version
> of root ?  For some earlier versions of root it was not a
> problem.  Is it a new bug ?
> 
> thanks
> Robert Michaels
> Jefferson Lab
> 
> {
> // This macro:  tsimple.C
> //
> // Why in this example must I have "R" instead
> // of "right" as the 1st argument of TTree ?
> //   right->Print`()   fails
> // but if I replace "right" by "R", then
> //   R->Print()  succeeds
> 
> // This problem occurs on a RH enterprise 3WS
> // with ROOT version 3.10/02  compiled with gcc 3.2.3
> // kernel 2.4.21-9.0.1.EL
> //
> // Most relevant is ROOT version, since 3.05/07
> // compiled with same compiler on same system
> // right->Print()  works fine.
> // Some earlier versions also work (3.02/07, 3.03/06).
> 
>   gROOT->Reset();
> 
>   Double_t px, py, ev, bb;
>   Int_t kout = 5000;
> 
>   TFile *hfile = new TFile("t.root","RECREATE","Demo");
> 
> // The following works ok -- can do "R->Print()"
> //  TTree *tree = new TTree("R","simple tree");
> 
> // But this does not work:
>    TTree *tree = new TTree("right","simple tree");
> 
> // Failure:
> // root [0] .x tsimple.C
> // root [1] right->Print()
> //Error: non class,struct,union object right used with . or -> FILE:(tmpfile) LINE:1
> //*** Interpreter error recovered ***
> // So you must:
> // root [2] TTree *R = (TTree*)gROOT.FindObject("right")
> // root [3] R->Print()
> // (no error now)
> 
>   tree->Branch("px",&px,"px/D",kout);
>   tree->Branch("py",&py,"py/D",kout);
>   tree->Branch("ev",&ev,"ev/D",kout);
>   tree->Branch("bb",&bb,"bb/D",kout);
> 
> 
> // Fill tree randomly
>   gRandom->SetSeed();
> 
>   for (Int_t i = 0; i < 5000; i++) {
>      gRandom->Rannor(px,py);
>      ev = ev+1;
>      bb = 40*ev+1000;
>      tree->Fill();
>   }
> 
>   tree->Write();
> 
> }



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