Re: ATLFast root file

Rene Brun (Rene.Brun@cern.ch)
Wed, 01 Jul 1998 15:08:37 +0200

Wei Xie wrote:
>
> Dear ROOTers'
>
> I want only to see how "ATLFDisplay" works. We have no "Pythia"
> locally and can not generate event with it, but I finally get the lib
> files:
>
> libAtlfast.so libAtlfastg.so
>
> I load these two file into ROOT, and type:
>
> ** test = new ATLFDisplay("test");
>
> ROOT immediately gives the following errors messages:
>
> -- *** Break *** segmentation violation
>
> -- ( 0) 0xc134eb10 StackTrace__11TUnixSystemFv + 0x28
> -- [/data7/dst/ROOT/root/lib/libUnix.sl]
> -- ( 1) 0xc134d508 DispatchSignals__11TUnixSystemF8ESignals + 0x150
> -- [/data7/dst/ROOT/root/lib/libUnix.sl]
> -- ...................
>
> Could you help me to generate an ROOT event file, so that I can
> directly run "display.C" to see how it works ?
>

As explained in the ATLFast documentation, the event display class
requires the main object ATLFast to be created before.
I have stored a Root file generated with 100 Pythia events
on the Root Web site at
ftp://root.cern.ch/root/atlfast.root
You can dowload this file and run the following macro (also
in the Atlfast distribution kit) display.C

void display(char *filename="atlfast.root")
{
gROOT->Reset();

gROOT->Macro("$ATLFAST/loadlibs");
gROOT->Macro("GL.C");

// Open the root input file
TFile *file = new TFile(filename);
ATLFast *atlfast = (ATLFast*)file.Get("atlfast");
atlfast->GetEvent(0);

ATLFDisplay *disp = new ATLFDisplay("ATLFast/ROOT event display");
disp->ShowNextEvent(0);
}

Rene Brun