JBell.cc

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#include <string>
#include <iostream>
#include <iomanip>
 
#include "TROOT.h"
#include "TFile.h"
#include "TH1D.h"
 
#include "JMath/JBell.hh"
 
#include "Jeep/JParser.hh"
 
 
/**
 * Example program to plot Bell function.
 *
 * \author mdejong
 */
int main(int argc, char **argv)
{
  using namespace std;
  using namespace JPP;
 
  string         outputFile;
  double         sigma;
  double         alpha;
  int            debug;
 
  try { 
 
    JParser<> zap("Example program to plot Bell function.");
 
    zap['o'] = make_field(outputFile)          = "";
    zap['s'] = make_field(sigma)               = 1.0;
    zap['a'] = make_field(alpha);
    zap['d'] = make_field(debug)               = 1;
    
    zap(argc, argv);
  }
  catch(const exception& error) {
    FATAL(error.what() << endl);
  }
 
 
  const JBell bell(0.0, sigma, 1.0, 0.0, alpha);
 
  TFile out(outputFile.c_str(), "recreate");
 
  const double xmin =  -7.0    * sigma;
  const double xmax =  +7.0    * sigma;
  const double dx   =   1.0e-4 * sigma;
  const int    nx   = (int) ((xmax - xmin) / dx);
 
  TH1D h0("h0", "", nx, xmin, xmax);
 
  for (Int_t i = 1; i != h0.GetXaxis()->GetNbins(); ++i) {
 
    const Double_t x = h0.GetXaxis()->GetBinCenter(i);
    const Double_t y = bell(x);
    
    h0.SetBinContent(i, y);
  }
  
  out.Write();
  out.Close();
}