boost/random/uniform_real.hpp
/* boost random/uniform_real.hpp header file
*
* Copyright Jens Maurer 2000-2001
* Distributed under the Boost Software License, Version 1.0. (See
* accompanying file LICENSE_1_0.txt or copy at
* http://www.boost.org/LICENSE_1_0.txt)
*
* See http://www.boost.org for most recent version including documentation.
*
* $Id: uniform_real.hpp 41369 2007-11-25 18:07:19Z bemandawes $
*
* Revision history
* 2001-04-08 added min<max assertion (N. Becker)
* 2001-02-18 moved to individual header files
*/
#ifndef BOOST_RANDOM_UNIFORM_REAL_HPP
#define BOOST_RANDOM_UNIFORM_REAL_HPP
#include <cassert>
#include <iostream>
#include <boost/config.hpp>
#include <boost/limits.hpp>
#include <boost/static_assert.hpp>
namespace boost {
// uniform distribution on a real range
template<class RealType = double>
class uniform_real
{
public:
typedef RealType input_type;
typedef RealType result_type;
explicit uniform_real(RealType min_arg = RealType(0),
RealType max_arg = RealType(1))
: _min(min_arg), _max(max_arg)
{
#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
BOOST_STATIC_ASSERT(!std::numeric_limits<RealType>::is_integer);
#endif
assert(min_arg < max_arg);
}
// compiler-generated copy ctor and assignment operator are fine
result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return _min; }
result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const { return _max; }
void reset() { }
template<class Engine>
result_type operator()(Engine& eng) {
return static_cast<result_type>(eng() - eng.min BOOST_PREVENT_MACRO_SUBSTITUTION())
/ static_cast<result_type>(eng.max BOOST_PREVENT_MACRO_SUBSTITUTION() - eng.min BOOST_PREVENT_MACRO_SUBSTITUTION())
* (_max - _min) + _min;
}
#if !defined(BOOST_NO_OPERATORS_IN_NAMESPACE) && !defined(BOOST_NO_MEMBER_TEMPLATE_FRIENDS)
template<class CharT, class Traits>
friend std::basic_ostream<CharT,Traits>&
operator<<(std::basic_ostream<CharT,Traits>& os, const uniform_real& ud)
{
os << ud._min << " " << ud._max;
return os;
}
template<class CharT, class Traits>
friend std::basic_istream<CharT,Traits>&
operator>>(std::basic_istream<CharT,Traits>& is, uniform_real& ud)
{
is >> std::ws >> ud._min >> std::ws >> ud._max;
return is;
}
#endif
private:
RealType _min, _max;
};
} // namespace boost
#endif // BOOST_RANDOM_UNIFORM_REAL_HPP