// ----------------------------------------------------------------------------
// Utility functions to fill histograms with user defined random distributions.
//
// The first function will fill a histogram referred to by HepHist1D& hist
// with num samplings drawn from the CLHEP Random distribution referred to
// by HepRandom& dist.  It is assumed that the user has already instantiated
// the HepRandom distribution with the desired shape parameters as well as
// the HepHist1D histogram with the desired range and binning.
//
// Usage:
//
//      HBookFile*   tManager = new HBookFile( "fillRandom.rz" );
//      RanluxEngine Ranlux(19735091);
//      RandGamma    Gamma(Ranlux,3.0,2.0);
//
//      HepHist1D& refhist = Manager->hist1D("Gamma(3,2) 100000 entries",
//                                                    50,0.0f,10.0f);
//      fillRandom( Gamma, refhist,  100000 );
//
// The second function will fill a histogram referred to by HepHist1D& subhist
// with num samplings drawn from the histogram referred to by HepHist1D&
// refhist.  It is assumed that the reference histogram exists and represents
// a reasonably high statistics object with the desired shape parameters.
// Neither the range nor the binning of the subsample histogram is required to
// be the same as that for the reference histogram. Note however that changing
// the binning can produce some rather odd looking side effects.
//
// Usage:
//
// Assuming the high statistics reference histogram from the earlier example,
// we make subsets from it as follows -
//
//      HepHist1D & subhist = Manager->hist1D("Gamma(3,2) 10000 samples",
//                                                   40,-3.0f,7.0f);
//      fillRandom( refhist, subhist, 10000 );
//
// A valid question here is, "Why is this thing in ZMtools and not in
// either CLHEP/Random or HepTuple?" The answer is that we don't want
// either of those to be dependent on the other.  That's a nice sentiment
// but putting it here makes ZMtools dependent on both CLHEP and HepTuple.
// Is that a good compromise? You should live so long!
//
// History:
//	21-Dec-1999	JMM	Initial draft.
//
// ----------------------------------------------------------------------------


#ifndef HEPFILLRANDOM_H
#define HEPFILLRANDOM_H

#include "ZMutility/ZMenvironment.h"

#include "HepTuple/HepHist1D.h"
#include "CLHEP/Random/Randomize.h"

ZM_BEGIN_NAMESPACE( zmht )	/*  namespace zmht  {     */

void fillRandom( HepRandom& dist, HepHist1D& hist, int num );

void fillRandom( HepHist1D& refhist, HepHist1D& subhist, int num );

ZM_END_NAMESPACE( zmht )	/*  }  // namespace zmht  */

#endif  // HEPFILLRANDOM_H