randgen.hpp

来自「模拟退火算法来源于固体退火原理」· HPP 代码 · 共 44 行

// randgen.hpp		A random number generator base class
//
//                      (c) Copyright 1994, Everett F. Carter Jr.
//                      Permission is granted by the author to use
//			this software for any application provided this
//			copyright notice is preserved.
//
// rcsid: @(#)randgen.hpp	1.5 %U 7/25/94   EFC

#ifndef RANDGEN_HPP_
#define RANDGEN_HPP_ 1.5

#include <iostream.h>
#include <limits.h>

#ifndef Real
#define Real	float
#endif

class RandomGenerator
{
	protected:
	  static ostream* ostr;		  // where error messages go
	  RandomGenerator() {}
        public:
	  virtual ~RandomGenerator() {}

	  virtual long seed(const long ik = 0) = 0;
	  virtual Real ranf() = 0;        // 0.0 .. 1.0 base generator for others
          virtual unsigned long int  rani();   // 0..n integer base generator

          // attach the output stream for error messages,
          // (cerr is used if this is not ever used)
          static void attach(ostream& os)       { ostr = &os; }
};

inline unsigned long int RandomGenerator::rani()
{
	return (unsigned long)( ULONG_MAX * ranf() );
        
}

#endif