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Diffstat (limited to 'src/third_party/boost-1.56.0/boost/random/uniform_smallint.hpp')
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diff --git a/src/third_party/boost-1.56.0/boost/random/uniform_smallint.hpp b/src/third_party/boost-1.56.0/boost/random/uniform_smallint.hpp deleted file mode 100644 index 4f5f437517d..00000000000 --- a/src/third_party/boost-1.56.0/boost/random/uniform_smallint.hpp +++ /dev/null @@ -1,288 +0,0 @@ -/* boost random/uniform_smallint.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. - * - * $Id$ - * - * Revision history - * 2001-04-08 added min<max assertion (N. Becker) - * 2001-02-18 moved to individual header files - */ - -#ifndef BOOST_RANDOM_UNIFORM_SMALLINT_HPP -#define BOOST_RANDOM_UNIFORM_SMALLINT_HPP - -#include <istream> -#include <iosfwd> -#include <boost/assert.hpp> -#include <boost/config.hpp> -#include <boost/limits.hpp> -#include <boost/type_traits/is_integral.hpp> -#include <boost/random/detail/config.hpp> -#include <boost/random/detail/operators.hpp> -#include <boost/random/detail/signed_unsigned_tools.hpp> -#include <boost/random/uniform_01.hpp> -#include <boost/detail/workaround.hpp> - -namespace boost { -namespace random { - -// uniform integer distribution on a small range [min, max] - -/** - * The distribution function uniform_smallint models a \random_distribution. - * On each invocation, it returns a random integer value uniformly distributed - * in the set of integer numbers {min, min+1, min+2, ..., max}. It assumes - * that the desired range (max-min+1) is small compared to the range of the - * underlying source of random numbers and thus makes no attempt to limit - * quantization errors. - * - * Let \f$r_{\mathtt{out}} = (\mbox{max}-\mbox{min}+1)\f$ the desired range of - * integer numbers, and - * let \f$r_{\mathtt{base}}\f$ be the range of the underlying source of random - * numbers. Then, for the uniform distribution, the theoretical probability - * for any number i in the range \f$r_{\mathtt{out}}\f$ will be - * \f$\displaystyle p_{\mathtt{out}}(i) = \frac{1}{r_{\mathtt{out}}}\f$. - * Likewise, assume a uniform distribution on \f$r_{\mathtt{base}}\f$ for - * the underlying source of random numbers, i.e. - * \f$\displaystyle p_{\mathtt{base}}(i) = \frac{1}{r_{\mathtt{base}}}\f$. - * Let \f$p_{\mathtt{out\_s}}(i)\f$ denote the random - * distribution generated by @c uniform_smallint. Then the sum over all - * i in \f$r_{\mathtt{out}}\f$ of - * \f$\displaystyle - * \left(\frac{p_{\mathtt{out\_s}}(i)}{p_{\mathtt{out}}(i)} - 1\right)^2\f$ - * shall not exceed - * \f$\displaystyle \frac{r_{\mathtt{out}}}{r_{\mathtt{base}}^2} - * (r_{\mathtt{base}} \mbox{ mod } r_{\mathtt{out}}) - * (r_{\mathtt{out}} - r_{\mathtt{base}} \mbox{ mod } r_{\mathtt{out}})\f$. - * - * The template parameter IntType shall denote an integer-like value type. - * - * @xmlnote - * The property above is the square sum of the relative differences - * in probabilities between the desired uniform distribution - * \f$p_{\mathtt{out}}(i)\f$ and the generated distribution - * \f$p_{\mathtt{out\_s}}(i)\f$. - * The property can be fulfilled with the calculation - * \f$(\mbox{base\_rng} \mbox{ mod } r_{\mathtt{out}})\f$, as follows: - * Let \f$r = r_{\mathtt{base}} \mbox{ mod } r_{\mathtt{out}}\f$. - * The base distribution on \f$r_{\mathtt{base}}\f$ is folded onto the - * range \f$r_{\mathtt{out}}\f$. The numbers i < r have assigned - * \f$\displaystyle - * \left\lfloor\frac{r_{\mathtt{base}}}{r_{\mathtt{out}}}\right\rfloor+1\f$ - * numbers of the base distribution, the rest has only \f$\displaystyle - * \left\lfloor\frac{r_{\mathtt{base}}}{r_{\mathtt{out}}}\right\rfloor\f$. - * Therefore, - * \f$\displaystyle p_{\mathtt{out\_s}}(i) = - * \left(\left\lfloor\frac{r_{\mathtt{base}}} - * {r_{\mathtt{out}}}\right\rfloor+1\right) / - * r_{\mathtt{base}}\f$ for i < r and \f$\displaystyle p_{\mathtt{out\_s}}(i) = - * \left\lfloor\frac{r_{\mathtt{base}}} - * {r_{\mathtt{out}}}\right\rfloor/r_{\mathtt{base}}\f$ otherwise. - * Substituting this in the - * above sum formula leads to the desired result. - * @endxmlnote - * - * Note: The upper bound for - * \f$(r_{\mathtt{base}} \mbox{ mod } r_{\mathtt{out}}) - * (r_{\mathtt{out}} - r_{\mathtt{base}} \mbox{ mod } r_{\mathtt{out}})\f$ is - * \f$\displaystyle \frac{r_{\mathtt{out}}^2}{4}\f$. Regarding the upper bound - * for the square sum of the relative quantization error of - * \f$\displaystyle \frac{r_\mathtt{out}^3}{4r_{\mathtt{base}}^2}\f$, it - * seems wise to either choose \f$r_{\mathtt{base}}\f$ so that - * \f$r_{\mathtt{base}} > 10r_{\mathtt{out}}^2\f$ or ensure that - * \f$r_{\mathtt{base}}\f$ is - * divisible by \f$r_{\mathtt{out}}\f$. - */ -template<class IntType = int> -class uniform_smallint -{ -public: - typedef IntType input_type; - typedef IntType result_type; - - class param_type - { - public: - - typedef uniform_smallint distribution_type; - - /** constructs the parameters of a @c uniform_smallint distribution. */ - param_type(IntType min_arg = 0, IntType max_arg = 9) - : _min(min_arg), _max(max_arg) - { - BOOST_ASSERT(_min <= _max); - } - - /** Returns the minimum value. */ - IntType a() const { return _min; } - /** Returns the maximum value. */ - IntType b() const { return _max; } - - - /** Writes the parameters to a @c std::ostream. */ - BOOST_RANDOM_DETAIL_OSTREAM_OPERATOR(os, param_type, parm) - { - os << parm._min << " " << parm._max; - return os; - } - - /** Reads the parameters from a @c std::istream. */ - BOOST_RANDOM_DETAIL_ISTREAM_OPERATOR(is, param_type, parm) - { - is >> parm._min >> std::ws >> parm._max; - return is; - } - - /** Returns true if the two sets of parameters are equal. */ - BOOST_RANDOM_DETAIL_EQUALITY_OPERATOR(param_type, lhs, rhs) - { return lhs._min == rhs._min && lhs._max == rhs._max; } - - /** Returns true if the two sets of parameters are different. */ - BOOST_RANDOM_DETAIL_INEQUALITY_OPERATOR(param_type) - - private: - IntType _min; - IntType _max; - }; - - /** - * Constructs a @c uniform_smallint. @c min and @c max are the - * lower and upper bounds of the output range, respectively. - */ - explicit uniform_smallint(IntType min_arg = 0, IntType max_arg = 9) - : _min(min_arg), _max(max_arg) {} - - /** - * Constructs a @c uniform_smallint from its parameters. - */ - explicit uniform_smallint(const param_type& parm) - : _min(parm.a()), _max(parm.b()) {} - - /** Returns the minimum value of the distribution. */ - result_type a() const { return _min; } - /** Returns the maximum value of the distribution. */ - result_type b() const { return _max; } - /** Returns the minimum value of the distribution. */ - result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return _min; } - /** Returns the maximum value of the distribution. */ - result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const { return _max; } - - /** Returns the parameters of the distribution. */ - param_type param() const { return param_type(_min, _max); } - /** Sets the parameters of the distribution. */ - void param(const param_type& parm) - { - _min = parm.a(); - _max = parm.b(); - } - - /** - * Effects: Subsequent uses of the distribution do not depend - * on values produced by any engine prior to invoking reset. - */ - void reset() { } - - /** Returns a value uniformly distributed in the range [min(), max()]. */ - template<class Engine> - result_type operator()(Engine& eng) const - { - typedef typename Engine::result_type base_result; - return generate(eng, boost::is_integral<base_result>()); - } - - /** Returns a value uniformly distributed in the range [param.a(), param.b()]. */ - template<class Engine> - result_type operator()(Engine& eng, const param_type& parm) const - { return uniform_smallint(parm)(eng); } - - /** Writes the distribution to a @c std::ostream. */ - BOOST_RANDOM_DETAIL_OSTREAM_OPERATOR(os, uniform_smallint, ud) - { - os << ud._min << " " << ud._max; - return os; - } - - /** Reads the distribution from a @c std::istream. */ - BOOST_RANDOM_DETAIL_ISTREAM_OPERATOR(is, uniform_smallint, ud) - { - is >> ud._min >> std::ws >> ud._max; - return is; - } - - /** - * Returns true if the two distributions will produce identical - * sequences of values given equal generators. - */ - BOOST_RANDOM_DETAIL_EQUALITY_OPERATOR(uniform_smallint, lhs, rhs) - { return lhs._min == rhs._min && lhs._max == rhs._max; } - - /** - * Returns true if the two distributions may produce different - * sequences of values given equal generators. - */ - BOOST_RANDOM_DETAIL_INEQUALITY_OPERATOR(uniform_smallint) - -private: - - // \cond show_private - template<class Engine> - result_type generate(Engine& eng, boost::mpl::true_) const - { - // equivalent to (eng() - eng.min()) % (_max - _min + 1) + _min, - // but guarantees no overflow. - typedef typename Engine::result_type base_result; - typedef typename boost::make_unsigned<base_result>::type base_unsigned; - typedef typename boost::make_unsigned<result_type>::type range_type; - range_type range = random::detail::subtract<result_type>()(_max, _min); - base_unsigned base_range = - random::detail::subtract<result_type>()((eng.max)(), (eng.min)()); - base_unsigned val = - random::detail::subtract<base_result>()(eng(), (eng.min)()); - if(range >= base_range) { - return boost::random::detail::add<range_type, result_type>()( - static_cast<range_type>(val), _min); - } else { - base_unsigned modulus = static_cast<base_unsigned>(range) + 1; - return boost::random::detail::add<range_type, result_type>()( - static_cast<range_type>(val % modulus), _min); - } - } - - template<class Engine> - result_type generate(Engine& eng, boost::mpl::false_) const - { - typedef typename Engine::result_type base_result; - typedef typename boost::make_unsigned<result_type>::type range_type; - range_type range = random::detail::subtract<result_type>()(_max, _min); - base_result val = boost::uniform_01<base_result>()(eng); - // what is the worst that can possibly happen here? - // base_result may not be able to represent all the values in [0, range] - // exactly. If this happens, it will cause round off error and we - // won't be able to produce all the values in the range. We don't - // care about this because the user has already told us not to by - // using uniform_smallint. However, we do need to be careful - // to clamp the result, or floating point rounding can produce - // an out of range result. - range_type offset = static_cast<range_type>(val * (static_cast<base_result>(range) + 1)); - if(offset > range) return _max; - return boost::random::detail::add<range_type, result_type>()(offset , _min); - } - // \endcond - - result_type _min; - result_type _max; -}; - -} // namespace random - -using random::uniform_smallint; - -} // namespace boost - -#endif // BOOST_RANDOM_UNIFORM_SMALLINT_HPP |