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Reference Guide
ntupleTableTest.C File Reference

Detailed Description

This TableTest class is a simple example of how to use a TGTable with a TTreeTableInterface.

TableTest inherits from TGMainFrame to create a top level frame to embed the TGTable in. First, the hsimple.root file is opened to obtain an ntuple. Then a TTreeTableInterface is created using this ntuple. A table is then created using the interface. In the end, the table is added to the TGMainFrame that is the TableTest and the necessary calls to correctly draw the window are made. For more information about the use of TTreeTableInterface and TGTable, see their documentation.

#include <iostream>
#include <TApplication.h>
#include <TGClient.h>
#include <TGButton.h>
#include <TGFrame.h>
#include <TGWindow.h>
#include <TString.h>
#include <TGTable.h>
#include <TFile.h>
#include <TNtuple.h>
#include <TSelectorDraw.h>
// A little class to automatically handle the generation of unique
// widget ids.
class IDList {
Int_t nID ; // Generates unique widget IDs.
IDList() : nID(0) {}
~IDList() {}
Int_t GetUnID(void) { return ++nID ; }
} ;
class TableTest : public TGMainFrame {
IDList fIDs ; // Generator for unique widget IDs.
UInt_t fNTableRows;
UInt_t fNTableColumns;
TGTable *fTable;
TFile *fFile;
TTreeTableInterface *fInterface;
TableTest(const TGWindow *p, UInt_t ntrows, UInt_t ntcols,
UInt_t w = 100, UInt_t h = 100) ;
virtual ~TableTest() ;
void DoExit() ;
TGTable *GetTable() { return fTable; }
TTreeTableInterface *GetInterface() { return fInterface; }
ClassDef(TableTest, 0)
TableTest::TableTest(const TGWindow *p, UInt_t ntrows, UInt_t ntcols,
: TGMainFrame(p, w, h), fNTableRows(ntrows), fNTableColumns(ntcols),
SetCleanup(kDeepCleanup) ;
Connect("CloseWindow()", "TableTest", this, "DoExit()") ;
DontCallClose() ;
// Open root file for the tree
fFile = new TFile("$ROOTSYS/tutorials/hsimple.root");
if (!fFile || fFile->IsZombie()) {
printf("Please run <ROOT location>/tutorials/hsimple.C first.");
// Get the ntuple from the file.
TNtuple *ntuple = (TNtuple *)fFile->Get("ntuple");
// Setup the expressions for the columns and the selection of the
// interface.
TString varexp = "px:py:pz:random:sin(px):log(px/py):log(pz)";
TString select = "";
TString options = "";
// Create the interface.
fInterface = new TTreeTableInterface(ntuple, varexp.Data(), select.Data(),
// Create the table and add it to the TableTest that is a TGMainFrame.
fTable = new TGTable(this, fIDs.GetUnID(), fInterface, fNTableRows,
AddFrame(fTable, new TGLayoutHints(kLHintsExpandX | kLHintsExpandY));
// Calls to layout and draw the TableTest that is a TGMainFrame.
SetWindowName("Tree Table Test") ;
MapSubwindows() ;
Resize(GetDefaultWidth()+20, 600) ;
MapWindow() ;
} ;
// Destructor
delete fInterface;
Cleanup() ;
void TableTest::DoExit()
// Exit this application via the Exit button or Window Manager.
// Use one of the both lines according to your needs.
// Please note to re-run this macro in the same ROOT session,
// you have to compile it to get signals/slots 'on place'.
DeleteWindow(); // to stay in the ROOT session
// gApplication->Terminate(); // to exit and close the ROOT session
TGTable *ntupleTableTest(UInt_t ntrows = 50, UInt_t ntcols = 10) {
TableTest *test = new TableTest(0, ntrows, ntcols, 500, 200);
return test->GetTable();
#define h(i)
Definition: RSha256.hxx:106
int Int_t
Definition: RtypesCore.h:45
unsigned int UInt_t
Definition: RtypesCore.h:46
#define ClassDef(name, id)
Definition: Rtypes.h:325
@ kDeepCleanup
Definition: TGFrame.h:50
@ kLHintsExpandY
Definition: TGLayout.h:38
@ kLHintsExpandX
Definition: TGLayout.h:37
A ROOT file is a suite of consecutive data records (TKey instances) with a well defined format.
Definition: TFile.h:54
A simple TTree restricted to a list of float variables only.
Definition: TNtuple.h:28
Basic string class.
Definition: TString.h:136
const char * Data() const
Definition: TString.h:369
TTreeTableInterface is used to interface to data that is stored in a TTree.
RooCmdArg Layout(Double_t xmin, Double_t xmax=0.99, Double_t ymin=0.95)
Definition: test.py:1
Roel Aaij 13/07/2007

Definition in file ntupleTableTest.C.