Macro load_packages.C not found

Dear ROOT community,
I am trying to analyse DAODs and have a code line which seems standard, ROOT.gROOT.Macro('$ROOTCOREDIR/scripts/load_packages.C') (inherited from a previous script). Upon trying to execute this, I get:

Error in <TROOT::Macro>: macro $ROOTCOREDIR/scripts/load_packages.C not found in path

Trying this in lxplus e.g. a line which reads root -b -q $ROOTCOREDIR/scripts/load_packages.C a similar error is manifested: Warning in <TApplication::GetOptions>: macro /scripts/load_packages.C not found.

Also, cd $ROOTCOREDIR leads to nowhere.
Can you please help? Could you please indicate how to use this macro both in lxplus and on a local machine?

_ROOT Version: 6.22.06
_Platform: Linux
_Compiler: g++

Hi Roy,

I take it you are an ATLAS user. Am I correct? If so, it makes more sense to address such questions to ATLAS people, e.g.,

Regarding your question, are you absolutely sure you have set an ATLAS release up? If so, which one?

Hi, I am indeed. Actually I’m merely trying to access an ATLAS xAOD. I’ve learnt that in order to load the load_packages.C macro one needs first to rcSetup -u; rcSetup Base,2.0.12. May I ask a general question about accessing an x/DAOD?

This is a very old way to access xAOD information. Not sure it is still maintained, but you definitely get access to the load_packages.C if you just do the following from a clean shell on lxplus:

setupATLAS && rcSetup Base,2.0.12

Thank you!
Brief question (which originally led me to this).
In my DAOD I have a TTree named CollectionTree which contains physics I’m interested in. I wish to extract information from it. Let’s take an example with a variable named TruthMuonsAuxDyn.e which is one of its leaves (clearly visible in TBrowser). When I try to run e.g.

for i in range(0, tree.GetEntries()):
     print (tree.TruthMuonsAuxDyn.e)

I get an error: AttributeError: 'TTree' object has no attribute 'TruthMuonsAuxDyn'. However when I do leaf = tree.GetLeaf("TruthMuonsAuxDyn.e") there is clearly no error. What am I missing? What would be the best way of extracting TruthMuonsAuxDyn.e of each event (and similarly, other variables)?

There is a tutorial explaining all this, which comes along with a framework to analyze DAODs: ATLAS Analysis Software Tutorial | Analysis Software Tutorial

In short, you have to write C++ code on top of the example given in that tutorial, probably something like the following:

// this happens for each event, as the event loop happens outside of user control:
  const xAOD::TruthMuonContainer* truthMuons = nullptr;
  ANA_CHECK(evtStore()->retrieve(truthMuons, "TruthMuons"));
  for (auto truth_muon : *truthMuons)
    ANA_MSG_INFO("e of the current truthMuon is " << truth_muon->e());

But you should go through the tutorial first.

Thanks. But just simply treating the DAOD as any TFile with TTress, TBranches etc., how can I extract that information, such as for the example I gave? For now ignoring all the ATLAS xAOD stuff.

To be honest I don’t know. You may have better luck asking people at

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