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

Hi Thiemo,

Indeed, the list of Alias put on the TChain is not yet passed onto the slave (where it should be merged with
the list of alias of the TTree); this will be fixed in a future release.

Cheers,
Philippe.

Thiemo Nagel wrote:
> 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
>
>
>
Received on Fri Jan 16 2009 - 17:01:31 CET