Problem with root file

ROOT
1

Hello,
I’m not sure this is a root problem or I’m just doing something wrong with c++… Anyhow I have a c++ program which read a tree and write many (thousends) of histogram in few files. The code I use is the following:

  ...
  int   nAlgo   = 5;
  int   nBinPt_ = 250;
  int   nBinEta = 50;

  TFile *myFile[nAlgo];
  TH1F* hDist_GJ[nAlgo][nBinEta][nBinPt_];

  for(int iAlg=0;iAlg<nAlgo;iAlg++) {

    myFile[iAlg] = new TFile(Form("histoFile_DR%03u_%d.root",drInt,iAlg),"RECREATE");

    for (Int_t i1=0; i1<nBinEta ; i1++)
      for (Int_t i2=0; i2<nBinPt_ ; i2++) {
        hDist_QJ[iAlg][i1][i2]= new TH1F(Form("hDist_QJ_%d_%d",i1,i2),"",200,0.5,1.5 );
      }
  }
...
  for(int iAlg=0;iAlg<nAlgo;iAlg++) {
    myFile[iAlg]->cd();
    cout << "Writing file for algo:" << iAlg << endl;
    myFile[iAlg]->Write();
  }

  cout << "End Writing and exiting" << endl;

  return 0;

}

The problem is that the program compile, run but it’s not exiting… I see on the standard output:

End Writing and exiting

and then the program stuck. If I ctrl^C, the program stops, the output file is correctly written and I can use it…

I can survive like this but I cannot use my program in a script because it’s not exiting…

So my question is: is the example code correct? If you like I can give you a code example to run

Thanks for helping.

Attilio

2

Please provide the shortest possible (but RUNNING) script reproducing this problem and indicate your version of ROOT.

Rene

3

This is an example which show the problem. This is an old problem for me… present with different root version… the one I’m using now is 5.14/00 but I have the same problem also with 5.18/00. To run the example is enough to untar, make and run the program.
Thanks

Attilio
example.gtar (146 KB)

4

In your loop writing histograms, clear the directory , otherwise it will take a lot of time at the end of the job when ROOT closes automatically files that have not yet been closed, ie

for(int iAlg=0;iAlg<nAlgo;iAlg++) { myFile[iAlg]->cd(); cout << "Writing file for algo:" << iAlg << endl; myFile[iAlg]->Write(); gDirectory->Clear(); //<====== }

5

Thanks! That solve the problem.

Attilio