How can I know the collections stored in a POOL file, like an ESD, AOD or DPD?

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How can I know which methods I can use, associated to the collections inside a POOL file?

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For an interactive work you can use Interactive Athena. Download the script you can find attached to this page, below, remove the trailing .txt renaming it to Interactive_topO.py. In your run/ directory run this script with athena -i Interactive_topO.py and follow the instruction written in the script code.

from AthenaCommon.AppMgr import ServiceMgr
import AthenaPoolCnvSvc.ReadAthenaPool

ServiceMgr.EventSelector.InputCollections = [ "/localscratch/christov/testData/valid1.005188.A3_Ztautau_filter.recon.AOD.e322_a76/AOD.029124._00002.pool.root.1" ]

# Number of Events to process
theApp.EvtMax = -1

# initialize AnalysisCore
include ("PyAnalysisCore/InitPyAnalysisCore.py")

## to start the interactive session
# athena -i Interactive_topO.py 

## In the session do the following:

#theApp.initialize()
#theApp.nextEvent()

## getting the vectors of particles form containers

#tau=PyParticleTools.getTauJets("TauRecContainer")
#el=PyParticleTools.getElectrons("ElectronAODCollection")

#mu=PyParticleTools.getMuons("StacoMuonCollection")
#jet=PyParticleTools.getParticleJets("Cone4H1TowerParticleJets") #didnt work
#met=PyParticleTools.getMissingET("MET_RefFinal")

## getting a single particle
#t0=tau[0]

## getting lest of available methods with some info
#help(t0)

check also: http://atlas-wiki1.physik.uni-bonn.de/mediawiki/index.php/Athena_Tipps_und_Tricks#Interactive_Athena

-- RiccardoMariaBianchi - 26 Feb 2009