To Write objects in different files

[Liuyao_Zhang]

Hello,

I want to divide all Entries into differrent output based on some selection.
Such as,

TFile* fout[10];
for(int i=0; i<10; i++){
   std::string outputfile_sec = outputfile + "_" + std::to_string(i) + ".root";
   fout[i] = new TFile(outputfile_sec.c_str(),"RECREATE");
 }

for(Long64_t ii=0; ii<n_entries; ii++){
tree->GetEntry(ii);
Double_t rannum = gRandom->Uniform(0, 1);   
bin = BinCreat->FindBin(rannum);
fout[bin-1]->cd(); // enter into differrent files. 
...
a->Fill(); 
b->Fill();
}

'But I don't know how to a->Write() to match different files in next Write section?'

[Wile_E_Coyote]

You need to create separate trees in each output file.

[Liuyao_Zhang]

Thanks, I created an array for file, and the correspoonding arrays for the histograms, and resloved the problem.