134 lines
3.8 KiB
C++
Executable File
134 lines
3.8 KiB
C++
Executable File
/* boost random/variate_generator.hpp header file
|
|
*
|
|
* Copyright Jens Maurer 2002
|
|
* 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: variate_generator.hpp 27375 2005-02-14 11:53:50Z johnmaddock $
|
|
*
|
|
*/
|
|
|
|
#ifndef BOOST_RANDOM_RANDOM_GENERATOR_HPP
|
|
#define BOOST_RANDOM_RANDOM_GENERATOR_HPP
|
|
|
|
#include <boost/config.hpp>
|
|
|
|
// implementation details
|
|
#include <boost/detail/workaround.hpp>
|
|
#include <boost/random/uniform_01.hpp>
|
|
#include <boost/random/detail/pass_through_engine.hpp>
|
|
#include <boost/random/detail/uniform_int_float.hpp>
|
|
#include <boost/random/detail/ptr_helper.hpp>
|
|
|
|
// Borland C++ 5.6.0 has problems using its numeric_limits traits as
|
|
// template parameters
|
|
#if BOOST_WORKAROUND(__BORLANDC__, <= 0x564)
|
|
#include <boost/type_traits/is_integral.hpp>
|
|
#endif
|
|
|
|
namespace boost {
|
|
|
|
namespace random {
|
|
namespace detail {
|
|
|
|
template<bool have_int, bool want_int>
|
|
struct engine_helper;
|
|
|
|
// for consistency, always have two levels of decorations
|
|
template<>
|
|
struct engine_helper<true, true>
|
|
{
|
|
template<class Engine, class DistInputType>
|
|
struct impl
|
|
{
|
|
typedef pass_through_engine<Engine> type;
|
|
};
|
|
};
|
|
|
|
template<>
|
|
struct engine_helper<false, false>
|
|
{
|
|
template<class Engine, class DistInputType>
|
|
struct impl
|
|
{
|
|
typedef uniform_01<Engine, DistInputType> type;
|
|
};
|
|
};
|
|
|
|
template<>
|
|
struct engine_helper<true, false>
|
|
{
|
|
template<class Engine, class DistInputType>
|
|
struct impl
|
|
{
|
|
typedef uniform_01<Engine, DistInputType> type;
|
|
};
|
|
};
|
|
|
|
template<>
|
|
struct engine_helper<false, true>
|
|
{
|
|
template<class Engine, class DistInputType>
|
|
struct impl
|
|
{
|
|
typedef uniform_int_float<Engine, unsigned long> type;
|
|
};
|
|
};
|
|
|
|
} // namespace detail
|
|
} // namespace random
|
|
|
|
|
|
template<class Engine, class Distribution>
|
|
class variate_generator
|
|
{
|
|
private:
|
|
typedef random::detail::pass_through_engine<Engine> decorated_engine;
|
|
|
|
public:
|
|
typedef typename decorated_engine::base_type engine_value_type;
|
|
typedef Engine engine_type;
|
|
typedef Distribution distribution_type;
|
|
typedef typename Distribution::result_type result_type;
|
|
|
|
variate_generator(Engine e, Distribution d)
|
|
: _eng(decorated_engine(e)), _dist(d) { }
|
|
|
|
result_type operator()() { return _dist(_eng); }
|
|
template<class T>
|
|
result_type operator()(T value) { return _dist(_eng, value); }
|
|
|
|
engine_value_type& engine() { return _eng.base().base(); }
|
|
const engine_value_type& engine() const { return _eng.base().base(); }
|
|
|
|
distribution_type& distribution() { return _dist; }
|
|
const distribution_type& distribution() const { return _dist; }
|
|
|
|
result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return (distribution().min)(); }
|
|
result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const { return (distribution().max)(); }
|
|
|
|
private:
|
|
#if BOOST_WORKAROUND(__BORLANDC__, <= 0x564)
|
|
typedef typename random::detail::engine_helper<
|
|
boost::is_integral<typename decorated_engine::result_type>::value,
|
|
boost::is_integral<typename Distribution::input_type>::value
|
|
>::BOOST_NESTED_TEMPLATE impl<decorated_engine, typename Distribution::input_type>::type internal_engine_type;
|
|
#else
|
|
enum {
|
|
have_int = std::numeric_limits<typename decorated_engine::result_type>::is_integer,
|
|
want_int = std::numeric_limits<typename Distribution::input_type>::is_integer
|
|
};
|
|
typedef typename random::detail::engine_helper<have_int, want_int>::BOOST_NESTED_TEMPLATE impl<decorated_engine, typename Distribution::input_type>::type internal_engine_type;
|
|
#endif
|
|
|
|
internal_engine_type _eng;
|
|
distribution_type _dist;
|
|
};
|
|
|
|
} // namespace boost
|
|
|
|
#endif // BOOST_RANDOM_RANDOM_GENERATOR_HPP
|