Logo ROOT   master
Reference Guide
h1analysisTreeReader.C File Reference

Detailed Description

View in nbviewer Open in SWAN H1 analysis example expressed in terms of TTreeReader

#include "TStyle.h"
#include "TCanvas.h"
#include "TPaveStats.h"
#include "TLine.h"
#include "TMath.h"
#include "TFile.h"
#include "TROOT.h"
const Double_t dxbin = (0.17-0.13)/40; // Bin-width
const Double_t sigma = 0.0012;
//_____________________________________________________________________
{
Double_t x = xx[0];
if (x <= 0.13957) return 0;
Double_t xp3 = (x-par[3])*(x-par[3]);
Double_t res = dxbin*(par[0]*TMath::Power(x-0.13957, par[1])
+ par[2] / 2.5066/par[4]*TMath::Exp(-xp3/2/par[4]/par[4]));
return res;
}
//_____________________________________________________________________
{
Double_t x = xx[0];
if (x <= 0.13957) return 0;
Double_t xp3 = (x-0.1454)*(x-0.1454);
Double_t res = dxbin*(par[0]*TMath::Power(x-0.13957, 0.25)
+ par[1] / 2.5066/sigma*TMath::Exp(-xp3/2/sigma/sigma));
return res;
}
//_____________________________________________________________________
// entry is the entry number in the current Tree
// Selection function to select D* and D0.
//in case one entry list is given in input, the selection has already been done.
if (!useList) {
// Return as soon as a bad entry is detected
if (TMath::Abs(*fMd0_d-1.8646) >= 0.04) return kFALSE;
if (*fPtds_d <= 2.5) return kFALSE;
if (TMath::Abs(*fEtads_d) >= 1.5) return kFALSE;
(*fIk)--; //original fIk used f77 convention starting at 1
(*fIpi)--;
if (fNhitrp.At(*fIk)* fNhitrp.At(*fIpi) <= 1) return kFALSE;
if (fRend.At(*fIk) -fRstart.At(*fIk) <= 22) return kFALSE;
if (fRend.At(*fIpi)-fRstart.At(*fIpi) <= 22) return kFALSE;
if (fNlhk.At(*fIk) <= 0.1) return kFALSE;
if (fNlhpi.At(*fIpi) <= 0.1) return kFALSE;
(*fIpis)--; if (fNlhpi.At(*fIpis) <= 0.1) return kFALSE;
if (*fNjets < 1) return kFALSE;
}
// if option fillList, fill the entry list
if (fillList) elist->Enter(entry);
//fill some histograms
h2->Fill(*fDm_d,*fRpd0_t/0.029979*1.8646/ *fPtd0_d);
return kTRUE;
}
// function called before starting the event loop
// -it performs some cleanup
// -it creates histograms
// -it sets some initialisation for the entry list
Reset();
//print the option specified in the Process function.
TString option = GetOption();
Info("Begin", "starting h1analysis with process option: %s", option.Data());
delete gDirectory->GetList()->FindObject("elist");
// case when one creates/fills the entry list
if (option.Contains("fillList")) {
elist = new TEntryList("elist", "H1 selection from Cut");
// Add to the input list for processing in PROOF, if needed
if (fInput) {
fInput->Add(new TNamed("fillList",""));
// We send a clone to avoid double deletes when importing the result
// This is needed to avoid warnings from output-to-members mapping
elist = 0;
}
Info("Begin", "creating an entry-list");
}
// case when one uses the entry list generated in a previous call
if (option.Contains("useList")) {
if (fInput) {
// In PROOF option "useList" is processed in SlaveBegin and we do not need
// to do anything here
} else {
TFile f("elist.root");
elist = (TEntryList*)f.Get("elist");
if (elist) elist->SetDirectory(0); //otherwise the file destructor will delete elist
}
}
}
// function called before starting the event loop
// -it performs some cleanup
// -it creates histograms
// -it sets some initialisation for the entry list
Init(myTree);
//print the option specified in the Process function.
TString option = GetOption();
Info("SlaveBegin",
"starting h1analysis with process option: %s (tree: %p)", option.Data(), myTree);
//create histograms
hdmd = new TH1F("hdmd","Dm_d",40,0.13,0.17);
h2 = new TH2F("h2","ptD0 vs Dm_d",30,0.135,0.165,30,-3,6);
// Entry list stuff (re-parse option because on PROOF only SlaveBegin is called)
if (option.Contains("fillList")) {
// Get the list
if (fInput) {
if ((elist = (TEntryList *) fInput->FindObject("elist")))
// Need to clone to avoid problems when destroying the selector
if (elist)
else
}
}
if (fillList) Info("SlaveBegin", "creating an entry-list");
if (option.Contains("useList")) useList = kTRUE;
}
// function called at the end of the event loop
hdmd = dynamic_cast<TH1F*>(fOutput->FindObject("hdmd"));
h2 = dynamic_cast<TH2F*>(fOutput->FindObject("h2"));
if (hdmd == 0 || h2 == 0) {
Error("Terminate", "hdmd = %p , h2 = %p", hdmd, h2);
return;
}
//create the canvas for the h1analysis fit
TCanvas *c1 = new TCanvas("c1","h1analysis analysis",10,10,800,600);
c1->SetBottomMargin(0.15);
hdmd->GetXaxis()->SetTitle("m_{K#pi#pi} - m_{K#pi}[GeV/c^{2}]");
//fit histogram hdmd with function f5 using the loglfIkelihood option
if (gROOT->GetListOfFunctions()->FindObject("f5"))
delete gROOT->GetFunction("f5");
TF1 *f5 = new TF1("f5",fdm5,0.139,0.17,5);
f5->SetParameters(1000000, .25, 2000, .1454, .001);
hdmd->Fit("f5","lr");
//create the canvas for tau d0
TCanvas *c2 = new TCanvas("c2","tauD0",100,100,800,600);
c2->SetGrid();
c2->SetBottomMargin(0.15);
// Project slices of 2-d histogram h2 along X , then fit each slice
// with function f2 and make a histogram for each fit parameter
// Note that the generated histograms are added to the list of objects
// in the current directory.
if (gROOT->GetListOfFunctions()->FindObject("f2"))
delete gROOT->GetFunction("f2");
TF1 *f2 = new TF1("f2",fdm2,0.139,0.17,2);
f2->SetParameters(10000, 10);
h2->FitSlicesX(f2,0,-1,1,"qln");
TH1D *h2_1 = (TH1D*)gDirectory->Get("h2_1");
h2_1->GetXaxis()->SetTitle("#tau[ps]");
h2_1->SetMarkerStyle(21);
h2_1->Draw();
c2->Update();
TLine *line = new TLine(0,0,0,c2->GetUymax());
line->Draw();
// Have the number of entries on the first histogram (to cross check when running
// with entry lists)
psdmd->SetOptStat(1110);
c1->Modified();
//save the entry list to a Root file if one was produced
if (fillList) {
if (!elist)
elist = dynamic_cast<TEntryList*>(fOutput->FindObject("elist"));
if (elist) {
Printf("Entry list 'elist' created:");
TFile efile("elist.root","recreate");
} else {
Error("Terminate", "entry list requested but not found in output");
}
}
// Notify the amount of processed events
if (!fInput) Info("Terminate", "processed %lld events", fProcessed);
}
}
// called when loading a new file
// get branch pointers
Info("Notify","processing file: %s",myTreeReader.GetTree()->GetCurrentFile()->GetName());
if (fillList) {
} else if (useList) {
}
}
return kTRUE;
}
Author
Anders Eie, 2013

Definition in file h1analysisTreeReader.C.