Logo ROOT   6.07/09
Reference Guide
ProofNtuple.C File Reference

Detailed Description

Selector to fill a simple ntuple.

#define ProofNtuple_cxx
#include "ProofNtuple.h"
#include <TCanvas.h>
#include <TFrame.h>
#include <TPaveText.h>
#include <TMath.h>
#include <TNtuple.h>
#include <TRandom3.h>
#include <TROOT.h>
#include <TString.h>
#include <TStyle.h>
#include <TSystem.h>
#include <TFile.h>
//_____________________________________________________________________________
ProofNtuple::~ProofNtuple()
{
// Destructor
SafeDelete(fNtp);
SafeDelete(fNtp2);
SafeDelete(fFile);
SafeDelete(fRandom);
}
//_____________________________________________________________________________
void ProofNtuple::PlotNtuple(TNtuple *ntp, const char *ntptitle)
{
// Make some plots from the ntuple 'ntp'
//
// Create a canvas, with 2 pads
//
TCanvas *c1 = new TCanvas(Form("cv-%s", ntp->GetName()), ntptitle,800,10,700,780);
c1->Divide(1,2);
TPad *pad1 = (TPad *) c1->GetPad(1);
TPad *pad2 = (TPad *) c1->GetPad(2);
//
// Display a function of one ntuple column imposing a condition
// on another column.
pad1->cd();
pad1->SetGrid();
pad1->SetLogy();
pad1->GetFrame()->SetFillColor(15);
ntp->SetLineColor(1);
ntp->SetFillStyle(1001);
ntp->SetFillColor(45);
ntp->Draw("3*px+2","px**2+py**2>1");
ntp->SetFillColor(38);
ntp->Draw("2*px+2","pz>2","same");
ntp->SetFillColor(5);
ntp->Draw("1.3*px+2","(px^2+py^2>4) && py>0","same");
pad1->RedrawAxis();
//
// Display a 3-D scatter plot of 3 columns. Superimpose a different selection.
pad2->cd();
ntp->Draw("pz:py:px","(pz<10 && pz>6)+(pz<4 && pz>3)");
ntp->SetMarkerColor(4);
ntp->Draw("pz:py:px","pz<6 && pz>4","same");
ntp->SetMarkerColor(5);
ntp->Draw("pz:py:px","pz<4 && pz>3","same");
TPaveText *l2 = new TPaveText(0.,0.6,0.9,0.95);
l2->SetFillColor(42);
l2->SetTextAlign(12);
l2->AddText("You can interactively rotate this view in 2 ways:");
l2->AddText(" - With the RotateCube in clicking in this pad");
l2->AddText(" - Selecting View with x3d in the View menu");
l2->Draw();
// Final update
c1->cd();
c1->Update();
}
//_____________________________________________________________________________
void ProofNtuple::Begin(TTree * /*tree*/)
{
// The Begin() function is called at the start of the query.
// When running with PROOF Begin() is only called on the client.
// The tree argument is deprecated (on PROOF 0 is passed).
TString option = GetOption();
TNamed *out = (TNamed *) fInput->FindObject("PROOF_NTUPLE_DONT_PLOT");
if (out) fPlotNtuple = kFALSE;
}
//_____________________________________________________________________________
void ProofNtuple::SlaveBegin(TTree * /*tree*/)
{
// The SlaveBegin() function is called after the Begin() function.
// When running with PROOF SlaveBegin() is called on each slave server.
// The tree argument is deprecated (on PROOF 0 is passed).
TString option = GetOption();
// We may be creating a dataset or a merge file: check it
TNamed *nm = dynamic_cast<TNamed *>(fInput->FindObject("SimpleNtuple.root"));
if (nm) {
// Just create the object
fProofFile = new TProofOutputFile("SimpleNtuple.root",
} else {
// For the ntuple, we use the automatic file merging facility
// Check if an output URL has been given
TNamed *out = (TNamed *) fInput->FindObject("PROOF_OUTPUTFILE_LOCATION");
Info("SlaveBegin", "PROOF_OUTPUTFILE_LOCATION: %s", (out ? out->GetTitle() : "undef"));
fProofFile = new TProofOutputFile("SimpleNtuple.root", (out ? out->GetTitle() : "M"));
out = (TNamed *) fInput->FindObject("PROOF_OUTPUTFILE");
if (out) fProofFile->SetOutputFileName(out->GetTitle());
}
// Open the file
fFile = fProofFile->OpenFile("RECREATE");
if (fFile && fFile->IsZombie()) SafeDelete(fFile);
// Cannot continue
if (!fFile) {
Info("SlaveBegin", "could not create '%s': instance is invalid!", fProofFile->GetName());
return;
}
// Now we create the ntuple
fNtp = new TNtuple("ntuple","Demo ntuple","px:py:pz:random:i");
// File resident
fNtp->SetDirectory(fFile);
fNtp->AutoSave();
// Now we create the second ntuple
fNtp2 = new TNtuple("ntuple2","Demo ntuple2","vx:vy:vz");
// File resident
fNtp2->SetDirectory(fFile);
fNtp2->AutoSave();
// Should we generate the random numbers or take them from the ntuple ?
TNamed *unr = (TNamed *) fInput->FindObject("PROOF_USE_NTP_RNDM");
if (unr) {
// Get the ntuple from the input list
if (!(fNtpRndm = dynamic_cast<TNtuple *>(fInput->FindObject("NtpRndm")))) {
Warning("SlaveBegin",
"asked to use rndm ntuple but 'NtpRndm' not found in the"
" input list! Using the random generator");
fInput->Print();
} else {
Info("SlaveBegin", "taking randoms from input ntuple 'NtpRndm'");
}
}
// Init the random generator, if required
if (!fNtpRndm) fRandom = new TRandom3(0);
}
//_____________________________________________________________________________
Bool_t ProofNtuple::Process(Long64_t entry)
{
// The Process() function is called for each entry in the tree (or possibly
// keyed object in the case of PROOF) to be processed. The entry argument
// specifies which entry in the currently loaded tree is to be processed.
// It can be passed to either ProofNtuple::GetEntry() or TBranch::GetEntry()
// to read either all or the required parts of the data. When processing
// keyed objects with PROOF, the object is already loaded and is available
// via the fObject pointer.
//
// This function should contain the "body" of the analysis. It can contain
// simple or elaborate selection criteria, run algorithms on the data
// of the event and typically fill histograms.
//
// The processing can be stopped by calling Abort().
//
// Use fStatus to set the return value of TTree::Process().
//
// The return value is currently not used.
if (!fNtp) return kTRUE;
// Fill ntuple
Float_t px, py, random;
if (fNtpRndm) {
// Get the entry
Float_t *ar = fNtpRndm->GetArgs();
Long64_t ent = entry % fNtpRndm->GetEntries();
fNtpRndm->GetEntry(ent);
random = ar[0];
px = (Float_t) TMath::ErfInverse((Double_t)(ar[1]*2 - 1.)) * TMath::Sqrt(2.);
py = (Float_t) TMath::ErfInverse((Double_t)(ar[2]*2 - 1.)) * TMath::Sqrt(2.);
} else if (fRandom) {
fRandom->Rannor(px,py);
random = fRandom->Rndm();
} else {
Abort("no way to get random numbers! Stop processing", kAbortProcess);
return kTRUE;
}
Float_t pz = px*px + py*py;
Int_t i = (Int_t) entry;
fNtp->Fill(px,py,pz,random,i);
if (!fNtp2) return kTRUE;
// The second ntuple
Float_t vz = random * 2. - 1.;
fNtp2->Fill(px,py,vz);
return kTRUE;
}
//_____________________________________________________________________________
void ProofNtuple::SlaveTerminate()
{
// The SlaveTerminate() function is called after all entries or objects
// have been processed. When running with PROOF SlaveTerminate() is called
// on each slave server.
// Write the ntuple to the file
if (fFile) {
if (!fNtp) {
Error("SlaveTerminate", "'ntuple' is undefined!");
return;
}
Bool_t cleanup = kFALSE;
TDirectory *savedir = gDirectory;
if (fNtp->GetEntries() > 0) {
fFile->cd();
fNtp->Write(0, TObject::kOverwrite);
if (fNtp2 && fNtp2->GetEntries() > 0) fNtp2->Write(0, TObject::kOverwrite);
fProofFile->Print();
fOutput->Add(fProofFile);
} else {
cleanup = kTRUE;
}
fNtp->SetDirectory(0);
if (fNtp2) fNtp2->SetDirectory(0);
gDirectory = savedir;
fFile->Close();
// Cleanup, if needed
if (cleanup) {
TUrl uf(*(fFile->GetEndpointUrl()));
SafeDelete(fFile);
gSystem->Unlink(uf.GetFile());
SafeDelete(fProofFile);
}
}
}
//_____________________________________________________________________________
void ProofNtuple::Terminate()
{
// The Terminate() function is the last function to be called during
// a query. It always runs on the client, it can be used to present
// the results graphically or save the results to file.
// Do nothing is not requested (dataset creation run)
if (!fPlotNtuple) return;
// Get the ntuple from the file
if ((fProofFile =
dynamic_cast<TProofOutputFile*>(fOutput->FindObject("SimpleNtuple.root")))) {
TString outputFile(fProofFile->GetOutputFileName());
TString outputName(fProofFile->GetName());
outputName += ".root";
Printf("outputFile: %s", outputFile.Data());
// Read the ntuple from the file
fFile = TFile::Open(outputFile);
if (fFile) {
Printf("Managed to open file: %s", outputFile.Data());
fNtp = (TNtuple *) fFile->Get("ntuple");
} else {
Error("Terminate", "could not open file: %s", outputFile.Data());
}
if (!fFile) return;
} else {
Error("Terminate", "TProofOutputFile not found");
return;
}
// Plot ntuples
if (fNtp) PlotNtuple(fNtp, "proof ntuple");
}
Author
Gerardo Ganis (gerar.nosp@m.do.g.nosp@m.anis@.nosp@m.cern.nosp@m..ch)

Definition in file ProofNtuple.C.