Segmentation error while creating a tree

Dear developers,

I am running a macro and creating some variables like vetomupx, vetomupy etc. I want to save them in the form of tree i.e I want to create a tree of all variables. I donot understand it and it is giving a segmentation error. Kindly help me to resolve this issue. (10.5 KB)



can you share a minimal reproducer of the error you are dealing with together with the full information about your platform and the version of ROOT you are using?



I am sending you the path of the root file.


This is the root version installed on my server

Linux version 2.6.32-696.3.1.el6.x86_64 ( (gcc version 4.4.7 20120313 (Red Hat 4.4.7-18) (GCC) ) #1 SMP Wed May 31 08:51:37 CEST 2017

sorry this is not a root version but rather a platform and I’d lile a minimal reproducer, not the full analysis.


May be i am not getting exactly what you want. I am asking about how ton create a tree. I am sending you some lines of my macro in which I have generated some containers like vetomupx, vetomupy etc using lorentz vector and in next step i want to store these containers in a TTree and recreate a root file containing them. By doing this I have done something wrong due to which I am getting this error. Kindly check these lines.

float VetoMuphi(0), VetoMupt(0), VetoMueta(0), lelectronpt(0), lelectroneta(0), VetoMupx(0), VetoMupy(0), VetoMupz(0), VetoMuen(0);

float VetoMucharge(0);
// plots pt and eta of leading muon
if(nSelMuons >0.){
VetoMupt = selectedMuons[0].Pt();
VetoMueta = selectedMuons[0].Eta();
VetoMupx = selectedMuons[0].Px();
VetoMupy = selectedMuons[0].Py();
VetoMupz = selectedMuons[0].Pz();
VetoMuen = selectedMuons[0].E();
VetoMuphi = selectedMuons[0].Phi();
VetoMucharge = Mu_charge[0];

TFile *ff = new TFile(“output_Veto.root”,“RECREATE”);
TTree *t = new TTree(“AnaTree”,“an example tree”);
float VetoMupx, VetoMupy, VetoMupz, VetoMuen, VetoMucharge;



Without a reproducer one can only give general comments. A quick look at your file:

  • You are including a lot of headers twice. Include them only once!
  • You are using new TFile(...) to open the input file. Use TFile::Open("...") instead (especially because you are opening a root://... file (which should be a TNetFile)) - and add a check that the file exists, i.e. check that f != nullptr. Also check that the tree exists.
  • In the following code fragment, the second and fourth if can never be true. ```
    if (nSelLeptons != 3) continue;
    if (nSelLeptons > 3) continue;
    if (nvetoLeptons != 0) continue;
    if (nvetoLeptons > 0) continue;
- your program should not compile because you are redefining `VetoMupx, VetoMupy, VetoMupz, VetoMuen, VetoMucharge;` (lines 194+231)
- There is some indentation in your code, yet your indentation doesn't help to find out to which block a line belongs. Use a tool like clang-format to reformat your code!
 This also leads to the next point:
- you are opening the output file inside the event loop! Don't do that, your output tree will only have one event! (Also, you are missing the `delete ff; / delete f;`)
- finally a physics related question: is ` bool passVetoIso( Mu_id[m]==13 ? relIso<0.25 : true)` useful? For -13 no isolation? At least I would add a comment here.

Thank you so much for your suggestions. I will try to sort out it

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