C++ TLeaf::GetNdata方法代码示例

void GAInputTreeData::SetBranchAddressToHolder(string branch_name){
    if(!fTTree->GetBranch(branch_name.c_str())){
        cout << "[GAInputTreeData-E]: branch " << branch_name << 
                " is not found";
        throw 1;
    }
    fBranchName.push_back(branch_name);
    TLeaf *leaf = fTTree->GetBranch(branch_name.c_str())
        ->GetLeaf(branch_name.c_str());
    Int_t n_data = leaf->GetNdata();
    string type_name = leaf->GetTypeName();
    fEventDataHolderManager->AddDetector(type_name,branch_name, n_data);
}

void GAInputTreeData::SetAllBranches(){
    TObjArray* ArrayOfBranches = fTTree->GetListOfBranches();
    Int_t n_branch = ArrayOfBranches->GetEntries();
    cout << "[GAInputTreeData-M]:Loading " << n_branch << " branches from "
        << fTTree->GetName() << endl;
    for(int i_branch=0; i_branch<n_branch; i_branch++){
        TBranch* Branch = (TBranch*)ArrayOfBranches->At(i_branch);
        string branch_name = Branch->GetName();
        TLeaf *leaf = (TLeaf*)Branch->GetListOfLeaves()->At(0);//(branch_name.c_str());
        Int_t n_data = leaf->GetNdata();
        string type_name = leaf->GetTypeName();
        fBranchName.push_back(branch_name);
        fEventDataHolderManager->AddDetector(type_name, branch_name, n_data);
        cout << "[GAInputTreeData-M]:Loading branch " << branch_name
            << " (" << type_name << "[" << n_data << "])" << endl;
    }
}

void Example_tags(TString topDir = "/star/rcf/GC/daq/tags")
{
//////////////////////////////////////////////////////////////////////////
//                                                                      //
// Example_tags.C                                                       //
//                                                                      //
// shows how to use the STAR tags files                                 //
// Input: top level directory                                           //
//                                                                      //
// what it does:                                                        //
// 1. creates TChain from all tags files down from the topDir           //
// 2. loops over all events in the chain                                //
//                                                                      //
// owner: Alexandre V. Vaniachine <[email protected]>                //
//////////////////////////////////////////////////////////////////////////

  gSystem->Load("libTable");
  gSystem->Load("St_base");
  // start benchmarks
  gBenchmark = new TBenchmark();
  gBenchmark->Start("total");
   
  // set loop optimization level
  gROOT->ProcessLine(".O4");
  // gather all files from the same top directory into one chain
  // topDir must end with "/"
  topDir +='/';
  St_FileSet dirs(topDir);
  St_DataSetIter next(&dirs,0);
  St_DataSet *set = 0; 
  TChain chain("Tag");
  while ( (set = next()) ) {           
    if (strcmp(set->GetTitle(),"file") || 
	!(strstr(set->GetName(),".tags.root"))) continue;
    chain.Add(gSystem->ConcatFileName(topDir,set->Path()));
  }
  UInt_t nEvents = chain->GetEntries();
  cout<<"chained "<<nEvents<<" events "<<endl;

  TObjArray *files = chain.GetListOfFiles();
  UInt_t nFiles = files->GetEntriesFast();
  cout << "chained " << nFiles << " files from " << topDir << endl;

  TObjArray *leaves = chain.GetListOfLeaves();
  Int_t nleaves = leaves->GetEntriesFast();

  TString tableName = " ";
  TObjArray *tagTable = new TObjArray;

  Int_t tableCount = 0;
  Int_t *tableIndex = new Int_t[nleaves];
  Int_t tagCount = 0;

  // decode tag table names
  for (Int_t l=0;l<nleaves;l++) {
    TLeaf *leaf = (TLeaf*)leaves->UncheckedAt(l);
    tagCount+=leaf->GetNdata();
    TBranch *branch = leaf->GetBranch();
    // new tag table name
    if ( strstr(branch->GetName(), tableName.Data()) == 0 ) {
      tableName = branch->GetName();
      // the tableName is encoded in the branch Name before the "."
      tableName.Resize(tableName->Last('.'));
      tagTable->AddLast(new TObjString(tableName.Data()));
      tableCount++;
    }
    tableIndex[l]=tableCount-1;
  }
  cout << " tot num tables, tags = " << tableCount << "   " 
       << tagCount << endl << endl;

  //EXAMPLE 1: how to print out names of all tags and values for first event
  for (l=0;l<nleaves;l++) {
    leaf = (TLeaf*)leaves->UncheckedAt(l);
    branch = leaf->GetBranch();
    branch->GetEntry();
    // tag comment is in the title
    TString Title = leaf->GetTitle();
    Int_t dim = leaf->GetNdata();
    if (dim==1) {
      Title.ReplaceAll('['," '"); 
      Title.ReplaceAll(']',"'"); 
    }
    cout << "\n Table: ";
    cout.width(10);
    cout << ((TObjString*)tagTable->UncheckedAt(tableIndex[l]))->GetString()
	 <<" -- has tag: " << Title << endl;
    for (Int_t i=0;i<dim;i++) {
      cout <<"                               "<< leaf->GetName();
      if (dim>1) cout << '['<<i<<']';
      cout << " = " << leaf->GetValue(i) << endl; 
    }
  }

  // EXAMPLE 2: how to make a plot
  c1 = new TCanvas("c1","Beam-Gas Rejection",600,1000);
  gStyle->SetMarkerStyle(8);
  chain->Draw("n_trk_tpc[0]:n_trk_tpc[1]");

  // EXAMPLE 3: how to make a selection (write selected event numbers on the plot)
//.........这里部分代码省略.........