Chris@16: /* boost random/random_number_generator.hpp header file
Chris@16:  *
Chris@16:  * Copyright Jens Maurer 2000-2001
Chris@16:  * Distributed under the Boost Software License, Version 1.0. (See
Chris@16:  * accompanying file LICENSE_1_0.txt or copy at
Chris@16:  * http://www.boost.org/LICENSE_1_0.txt)
Chris@16:  *
Chris@16:  * See http://www.boost.org for most recent version including documentation.
Chris@16:  *
Chris@101:  * $Id$
Chris@16:  *
Chris@16:  * Revision history
Chris@16:  *  2001-02-18  moved to individual header files
Chris@16:  */
Chris@16: 
Chris@16: #ifndef BOOST_RANDOM_RANDOM_NUMBER_GENERATOR_HPP
Chris@16: #define BOOST_RANDOM_RANDOM_NUMBER_GENERATOR_HPP
Chris@16: 
Chris@16: #include <boost/assert.hpp>
Chris@16: #include <boost/random/uniform_int_distribution.hpp>
Chris@16: 
Chris@16: #include <boost/random/detail/disable_warnings.hpp>
Chris@16: 
Chris@16: namespace boost {
Chris@16: namespace random {
Chris@16: 
Chris@16: /**
Chris@16:  * Instantiations of class template random_number_generator model a
Chris@16:  * RandomNumberGenerator (std:25.2.11 [lib.alg.random.shuffle]). On
Chris@16:  * each invocation, it returns a uniformly distributed integer in
Chris@16:  * the range [0..n).
Chris@16:  *
Chris@16:  * The template parameter IntType shall denote some integer-like value type.
Chris@16:  */
Chris@16: template<class URNG, class IntType = long>
Chris@16: class random_number_generator
Chris@16: {
Chris@16: public:
Chris@16:     typedef URNG base_type;
Chris@16:     typedef IntType argument_type;
Chris@16:     typedef IntType result_type;
Chris@16:     /**
Chris@16:      * Constructs a random_number_generator functor with the given
Chris@16:      * \uniform_random_number_generator as the underlying source of
Chris@16:      * random numbers.
Chris@16:      */
Chris@16:     random_number_generator(base_type& rng) : _rng(rng) {}
Chris@16: 
Chris@16:     // compiler-generated copy ctor is fine
Chris@16:     // assignment is disallowed because there is a reference member
Chris@16: 
Chris@16:     /**
Chris@16:      * Returns a value in the range [0, n)
Chris@16:      */
Chris@16:     result_type operator()(argument_type n)
Chris@16:     {
Chris@16:         BOOST_ASSERT(n > 0);
Chris@16:         return uniform_int_distribution<IntType>(0, n-1)(_rng);
Chris@16:     }
Chris@16: 
Chris@16: private:
Chris@16:     base_type& _rng;
Chris@16: };
Chris@16: 
Chris@16: } // namespace random
Chris@16: 
Chris@16: using random::random_number_generator;
Chris@16: 
Chris@16: } // namespace boost
Chris@16: 
Chris@16: #include <boost/random/detail/enable_warnings.hpp>
Chris@16: 
Chris@16: #endif // BOOST_RANDOM_RANDOM_NUMBER_GENERATOR_HPP