boost/random/variate_generator.hpp
/* boost random/variate_generator.hpp header file
*
* Copyright Jens Maurer 2002
* Copyright Steven Watanabe 2011
* 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 71018 2011-04-05 21:27:52Z steven_watanabe $
*
*/
#ifndef BOOST_RANDOM_RANDOM_GENERATOR_HPP
#define BOOST_RANDOM_RANDOM_GENERATOR_HPP
#include <boost/random/detail/ptr_helper.hpp>
#include <boost/random/detail/disable_warnings.hpp>
namespace boost {
/// \cond hide_private_members
namespace random {
///\endcond
/**
* A random variate generator is used to join a random number
* generator together with a random number distribution.
* Boost.Random provides a vast choice of \generators as well
* as \distributions.
*
* The argument for the template parameter Engine shall be of
* the form U, U&, or U*, where U models a
* \uniform_random_number_generator. Then, the member
* engine_value_type names U (not the pointer or reference to U).
*
* Specializations of @c variate_generator satisfy the
* requirements of CopyConstructible. They also satisfy the
* requirements of Assignable unless the template parameter
* Engine is of the form U&.
*
* The complexity of all functions specified in this section
* is constant. No function described in this section except
* the constructor throws an exception.
*/
template<class Engine, class Distribution>
class variate_generator
{
private:
typedef boost::random::detail::ptr_helper<Engine> helper_type;
public:
typedef typename helper_type::value_type engine_value_type;
typedef Engine engine_type;
typedef Distribution distribution_type;
typedef typename Distribution::result_type result_type;
/**
* Constructs a @c variate_generator object with the associated
* \uniform_random_number_generator eng and the associated
* \random_distribution d.
*
* Throws: If and what the copy constructor of Engine or
* Distribution throws.
*/
variate_generator(Engine e, Distribution d)
: _eng(e), _dist(d) { }
/** Returns: distribution()(engine()) */
result_type operator()() { return _dist(engine()); }
/**
* Returns: distribution()(engine(), value).
*/
template<class T>
result_type operator()(const T& value) { return _dist(engine(), value); }
/**
* Returns: A reference to the associated uniform random number generator.
*/
engine_value_type& engine() { return helper_type::ref(_eng); }
/**
* Returns: A reference to the associated uniform random number generator.
*/
const engine_value_type& engine() const { return helper_type::ref(_eng); }
/** Returns: A reference to the associated \random_distribution. */
distribution_type& distribution() { return _dist; }
/**
* Returns: A reference to the associated random distribution.
*/
const distribution_type& distribution() const { return _dist; }
/**
* Precondition: distribution().min() is well-formed
*
* Returns: distribution().min()
*/
result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return (distribution().min)(); }
/**
* Precondition: distribution().max() is well-formed
*
* Returns: distribution().max()
*/
result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const { return (distribution().max)(); }
private:
Engine _eng;
distribution_type _dist;
};
} // namespace random
using random::variate_generator;
} // namespace boost
#include <boost/random/detail/enable_warnings.hpp>
#endif // BOOST_RANDOM_RANDOM_GENERATOR_HPP