DUniform.h

/*  _________________________________________________________________________
 *
 *  UTILIB: A utility library for developing portable C++ codes.
 *  Copyright (c) 2001, Sandia National Laboratories.
 *  This software is distributed under the GNU Lesser General Public License.
 *  For more information, see the README file in the top UTILIB directory.
 *  _________________________________________________________________________
 */

//
// DUniform.h
//
#ifndef __DUniform_h
#define __DUniform_h

#ifndef ANSI_HDRS
#include <math.h>
#else
#include <cmath>
#endif
#include "DRandVar.h"


class UTILIB_API DUniform: public DRandVar {

public:

    DUniform(RNG *gen=(RNG*)NULL, int low=0, int high=1);

    int low();
    int low(int x);
    int high();
    int high(int x);

    virtual int operator()();
    int operator()(int low_, int high_);

protected:

    int pLow;
    int pHigh;
    int delta;

};


inline DUniform::DUniform(RNG *gen, int low, int high)
:DRandVar(gen)
{
    pLow = (low < high) ? low : high;
    pHigh = (low < high) ? high : low;
    delta = pHigh - pLow;
}

inline int DUniform::low() { return pLow; }

inline int DUniform::low(int x) {
  int tmp = pLow;
  pLow = x;
  delta = pHigh - pLow;
  return tmp;
}

inline int DUniform::high() { return pHigh; }

inline int DUniform::high(int x) {
  int tmp = pHigh;
  pHigh = x;
  delta = pHigh - pLow;
  return tmp;
}


inline int DUniform::operator()(int low_, int high_)
{
low(low_);
high(high_);
return (*this)();
}


inline int DUniform::operator()()
{
RNG* rng;

if ((rng = generator()) == NULL) {
   ErrReturn("DUniform::operator() : Attempting to use a NULL RNG.");
   }
else {
   int temp = (int)floor(pLow + (pHigh-pLow+1) * rng->asDouble());
   if (temp > pHigh)
      temp = pHigh;             // This handles the case when urand == 1.0
   return(temp);
   }
}

#endif