ExampleMacro_GUI.C

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/*
 This piece of code demonstrates how a root macro is used as a standalone
    application with full acces the grapical user interface (GUI) of ROOT   */
 
// include ALL header files needed
#include "TROOT.h"
#include "TApplication.h"
#include "TBrowser.h"
#include "TFile.h"
#include "TH1F.h"
#include "TCanvas.h"
#include "TMath.h"
 
// eventually, include some additoinal C or C++ libraries
#include <cmath>
 
//     ==>>  put the code of your macro here
void ExampleMacro_GUI() {
  // Create a histogram, fill it with random gaussian numbers
  TH1F *h = new TH1F ("h", "example histogram", 100, -5.,5.);
  h->FillRandom("gaus",1000);
 
  // draw the histogram
  h->DrawClone();
 
/* - Create a new ROOT file for output
   - Note that this file may contain any kind of ROOT objects, histograms,
     pictures, graphics objects etc.
   - the new file is now becoming the current directory */
  TFile *f1 = new TFile("ExampleMacro.root","RECREATE","ExampleMacro");
 
  // write Histogram to current directory (i.e. the file just opened)
  h->Write();
 
  // Close the file.
  //   (You may inspect your histogram in the file using the TBrowser class)
  f1->Close();
}
 
// the "dressing" code for a stand-alone ROOT application starts here
void StandaloneApplication(int argc, char** argv) {
  // ==>> here the ROOT macro is called
  ExampleMacro_GUI();
}
 
// This is the standard main of C++ starting a ROOT application
int main(int argc, char** argv) {
   TApplication app("Root Application", &argc, argv);
   StandaloneApplication(app.Argc(), app.Argv());
   app.Run();
   return 0;
}