PROOF: TTree->SetAlias() and TTree->Draw()

From: Thiemo Nagel <thiemo.nagel_at_ph.tum.de>
Date: Wed, 14 Jan 2009 11:35:02 +0100

Hello,

somehow I can't get TTree->Draw() to work with aliases with PROOF, maybe somebody could be so kind to help me out.

I'm using ROOT v5.22. When executing t->Draw() using an alias, I'm getting the following error message (see [6] below):

TProofDrawHist::CompileVariables: Error compiling variables

Whereas everything works as expected without the alias [7].

The full transcript of the session is below.

Thanks a lot, kind regards,

Thiemo Nagel

nailgun:/tmp> root
Executing rootlogon.C done.
root [0] TProof *proof = TProof::Open("localhost"); Starting master: opening connection ...
Starting master: OK
Opening connections to workers: OK (4 workers) Setting up worker servers: OK (4 workers) PROOF set to parallel mode (4 workers)

root [1]   TChain *t = new TChain("NEUTRAL");
root [2]   t->Add("/......root");
root [3]   t->Add("/......root");
root [4]   t->SetAlias("p", "V");
root [5]   t->SetProof();
root [6]   t->Draw("p.type");

Looking up for exact location of files: OK (2 files) Looking up for exact location of files: OK (2 files) Validating files: OK (2 files)
<TCanvas::MakeDefCanvas>: created default TCanvas with name c1 Error in <TCanvas::Range>: illegal world coordinates range: x1=0.000000, y1=-0.131250, x2=0.000000, y2=1.181250
Error in <TCanvas::RangeAxis>: illegal axis coordinates range: xmin=0.000000, ymin=0.000000, xmax=0.000000, ymax=1.050000 Mst-0: grand total: sent 3 objects, size: 17709 bytes OBJ: TStatus PROOF_Status ERROR

        TProofDrawHist::CompileVariables: Error compiling variables Error in <TCanvas::Range>: illegal world coordinates range: x1=0.000000, y1=-0.131250, x2=0.000000, y2=1.181250
Error in <TCanvas::RangeAxis>: illegal axis coordinates range: xmin=0.000000, ymin=0.000000, xmax=0.000000, ymax=1.050000 root [7] t->Draw("V.type");
Looking up for exact location of files: OK (2 files) Looking up for exact location of files: OK (2 files) Validating files: OK (2 files)

Mst-0: grand total: sent 3 objects, size: 1641 bytes

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Received on Wed Jan 14 2009 - 11:35:08 CET