Mercurial > hg > vamp-build-and-test
diff DEPENDENCIES/generic/include/boost/random/mersenne_twister.hpp @ 16:2665513ce2d3
Add boost headers
author | Chris Cannam |
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date | Tue, 05 Aug 2014 11:11:38 +0100 |
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children | c530137014c0 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/DEPENDENCIES/generic/include/boost/random/mersenne_twister.hpp Tue Aug 05 11:11:38 2014 +0100 @@ -0,0 +1,545 @@ +/* boost random/mersenne_twister.hpp header file + * + * Copyright Jens Maurer 2000-2001 + * Copyright Steven Watanabe 2010 + * 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: mersenne_twister.hpp 74867 2011-10-09 23:13:31Z steven_watanabe $ + * + * Revision history + * 2001-02-18 moved to individual header files + */ + +#ifndef BOOST_RANDOM_MERSENNE_TWISTER_HPP +#define BOOST_RANDOM_MERSENNE_TWISTER_HPP + +#include <iosfwd> +#include <istream> +#include <stdexcept> +#include <boost/config.hpp> +#include <boost/cstdint.hpp> +#include <boost/integer/integer_mask.hpp> +#include <boost/random/detail/config.hpp> +#include <boost/random/detail/ptr_helper.hpp> +#include <boost/random/detail/seed.hpp> +#include <boost/random/detail/seed_impl.hpp> +#include <boost/random/detail/generator_seed_seq.hpp> + +namespace boost { +namespace random { + +/** + * Instantiations of class template mersenne_twister_engine model a + * \pseudo_random_number_generator. It uses the algorithm described in + * + * @blockquote + * "Mersenne Twister: A 623-dimensionally equidistributed uniform + * pseudo-random number generator", Makoto Matsumoto and Takuji Nishimura, + * ACM Transactions on Modeling and Computer Simulation: Special Issue on + * Uniform Random Number Generation, Vol. 8, No. 1, January 1998, pp. 3-30. + * @endblockquote + * + * @xmlnote + * The boost variant has been implemented from scratch and does not + * derive from or use mt19937.c provided on the above WWW site. However, it + * was verified that both produce identical output. + * @endxmlnote + * + * The seeding from an integer was changed in April 2005 to address a + * <a href="http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/emt19937ar.html">weakness</a>. + * + * The quality of the generator crucially depends on the choice of the + * parameters. User code should employ one of the sensibly parameterized + * generators such as \mt19937 instead. + * + * The generator requires considerable amounts of memory for the storage of + * its state array. For example, \mt11213b requires about 1408 bytes and + * \mt19937 requires about 2496 bytes. + */ +template<class UIntType, + std::size_t w, std::size_t n, std::size_t m, std::size_t r, + UIntType a, std::size_t u, UIntType d, std::size_t s, + UIntType b, std::size_t t, + UIntType c, std::size_t l, UIntType f> +class mersenne_twister_engine +{ +public: + typedef UIntType result_type; + BOOST_STATIC_CONSTANT(std::size_t, word_size = w); + BOOST_STATIC_CONSTANT(std::size_t, state_size = n); + BOOST_STATIC_CONSTANT(std::size_t, shift_size = m); + BOOST_STATIC_CONSTANT(std::size_t, mask_bits = r); + BOOST_STATIC_CONSTANT(UIntType, xor_mask = a); + BOOST_STATIC_CONSTANT(std::size_t, tempering_u = u); + BOOST_STATIC_CONSTANT(UIntType, tempering_d = d); + BOOST_STATIC_CONSTANT(std::size_t, tempering_s = s); + BOOST_STATIC_CONSTANT(UIntType, tempering_b = b); + BOOST_STATIC_CONSTANT(std::size_t, tempering_t = t); + BOOST_STATIC_CONSTANT(UIntType, tempering_c = c); + BOOST_STATIC_CONSTANT(std::size_t, tempering_l = l); + BOOST_STATIC_CONSTANT(UIntType, initialization_multiplier = f); + BOOST_STATIC_CONSTANT(UIntType, default_seed = 5489u); + + // backwards compatibility + BOOST_STATIC_CONSTANT(UIntType, parameter_a = a); + BOOST_STATIC_CONSTANT(std::size_t, output_u = u); + BOOST_STATIC_CONSTANT(std::size_t, output_s = s); + BOOST_STATIC_CONSTANT(UIntType, output_b = b); + BOOST_STATIC_CONSTANT(std::size_t, output_t = t); + BOOST_STATIC_CONSTANT(UIntType, output_c = c); + BOOST_STATIC_CONSTANT(std::size_t, output_l = l); + + // old Boost.Random concept requirements + BOOST_STATIC_CONSTANT(bool, has_fixed_range = false); + + + /** + * Constructs a @c mersenne_twister_engine and calls @c seed(). + */ + mersenne_twister_engine() { seed(); } + + /** + * Constructs a @c mersenne_twister_engine and calls @c seed(value). + */ + BOOST_RANDOM_DETAIL_ARITHMETIC_CONSTRUCTOR(mersenne_twister_engine, + UIntType, value) + { seed(value); } + template<class It> mersenne_twister_engine(It& first, It last) + { seed(first,last); } + + /** + * Constructs a mersenne_twister_engine and calls @c seed(gen). + * + * @xmlnote + * The copy constructor will always be preferred over + * the templated constructor. + * @endxmlnote + */ + BOOST_RANDOM_DETAIL_SEED_SEQ_CONSTRUCTOR(mersenne_twister_engine, + SeedSeq, seq) + { seed(seq); } + + // compiler-generated copy ctor and assignment operator are fine + + /** Calls @c seed(default_seed). */ + void seed() { seed(default_seed); } + + /** + * Sets the state x(0) to v mod 2w. Then, iteratively, + * sets x(i) to + * (i + f * (x(i-1) xor (x(i-1) rshift w-2))) mod 2<sup>w</sup> + * for i = 1 .. n-1. x(n) is the first value to be returned by operator(). + */ + BOOST_RANDOM_DETAIL_ARITHMETIC_SEED(mersenne_twister_engine, UIntType, value) + { + // New seeding algorithm from + // http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/emt19937ar.html + // In the previous versions, MSBs of the seed affected only MSBs of the + // state x[]. + const UIntType mask = (max)(); + x[0] = value & mask; + for (i = 1; i < n; i++) { + // See Knuth "The Art of Computer Programming" + // Vol. 2, 3rd ed., page 106 + x[i] = (f * (x[i-1] ^ (x[i-1] >> (w-2))) + i) & mask; + } + } + + /** + * Seeds a mersenne_twister_engine using values produced by seq.generate(). + */ + BOOST_RANDOM_DETAIL_SEED_SEQ_SEED(mersenne_twister_engine, SeeqSeq, seq) + { + detail::seed_array_int<w>(seq, x); + i = n; + + // fix up the state if it's all zeroes. + if((x[0] & (~static_cast<UIntType>(0) << r)) == 0) { + for(std::size_t j = 1; j < n; ++j) { + if(x[j] != 0) return; + } + x[0] = static_cast<UIntType>(1) << (w-1); + } + } + + /** Sets the state of the generator using values from an iterator range. */ + template<class It> + void seed(It& first, It last) + { + detail::fill_array_int<w>(first, last, x); + i = n; + + // fix up the state if it's all zeroes. + if((x[0] & (~static_cast<UIntType>(0) << r)) == 0) { + for(std::size_t j = 1; j < n; ++j) { + if(x[j] != 0) return; + } + x[0] = static_cast<UIntType>(1) << (w-1); + } + } + + /** Returns the smallest value that the generator can produce. */ + static result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () + { return 0; } + /** Returns the largest value that the generator can produce. */ + static result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () + { return boost::low_bits_mask_t<w>::sig_bits; } + + /** Produces the next value of the generator. */ + result_type operator()(); + + /** Fills a range with random values */ + template<class Iter> + void generate(Iter first, Iter last) + { detail::generate_from_int(*this, first, last); } + + /** + * Advances the state of the generator by @c z steps. Equivalent to + * + * @code + * for(unsigned long long i = 0; i < z; ++i) { + * gen(); + * } + * @endcode + */ + void discard(boost::uintmax_t z) + { + for(boost::uintmax_t j = 0; j < z; ++j) { + (*this)(); + } + } + +#ifndef BOOST_RANDOM_NO_STREAM_OPERATORS + /** Writes a mersenne_twister_engine to a @c std::ostream */ + template<class CharT, class Traits> + friend std::basic_ostream<CharT,Traits>& + operator<<(std::basic_ostream<CharT,Traits>& os, + const mersenne_twister_engine& mt) + { + mt.print(os); + return os; + } + + /** Reads a mersenne_twister_engine from a @c std::istream */ + template<class CharT, class Traits> + friend std::basic_istream<CharT,Traits>& + operator>>(std::basic_istream<CharT,Traits>& is, + mersenne_twister_engine& mt) + { + for(std::size_t j = 0; j < mt.state_size; ++j) + is >> mt.x[j] >> std::ws; + // MSVC (up to 7.1) and Borland (up to 5.64) don't handle the template + // value parameter "n" available from the class template scope, so use + // the static constant with the same value + mt.i = mt.state_size; + return is; + } +#endif + + /** + * Returns true if the two generators are in the same state, + * and will thus produce identical sequences. + */ + friend bool operator==(const mersenne_twister_engine& x, + const mersenne_twister_engine& y) + { + if(x.i < y.i) return x.equal_imp(y); + else return y.equal_imp(x); + } + + /** + * Returns true if the two generators are in different states. + */ + friend bool operator!=(const mersenne_twister_engine& x, + const mersenne_twister_engine& y) + { return !(x == y); } + +private: + /// \cond show_private + + void twist(); + + /** + * Does the work of operator==. This is in a member function + * for portability. Some compilers, such as msvc 7.1 and + * Sun CC 5.10 can't access template parameters or static + * members of the class from inline friend functions. + * + * requires i <= other.i + */ + bool equal_imp(const mersenne_twister_engine& other) const + { + UIntType back[n]; + std::size_t offset = other.i - i; + for(std::size_t j = 0; j + offset < n; ++j) + if(x[j] != other.x[j+offset]) + return false; + rewind(&back[n-1], offset); + for(std::size_t j = 0; j < offset; ++j) + if(back[j + n - offset] != other.x[j]) + return false; + return true; + } + + /** + * Does the work of operator<<. This is in a member function + * for portability. + */ + template<class CharT, class Traits> + void print(std::basic_ostream<CharT, Traits>& os) const + { + UIntType data[n]; + for(std::size_t j = 0; j < i; ++j) { + data[j + n - i] = x[j]; + } + if(i != n) { + rewind(&data[n - i - 1], n - i); + } + os << data[0]; + for(std::size_t j = 1; j < n; ++j) { + os << ' ' << data[j]; + } + } + + /** + * Copies z elements of the state preceding x[0] into + * the array whose last element is last. + */ + void rewind(UIntType* last, std::size_t z) const + { + const UIntType upper_mask = (~static_cast<UIntType>(0)) << r; + const UIntType lower_mask = ~upper_mask; + UIntType y0 = x[m-1] ^ x[n-1]; + if(y0 & (static_cast<UIntType>(1) << (w-1))) { + y0 = ((y0 ^ a) << 1) | 1; + } else { + y0 = y0 << 1; + } + for(std::size_t sz = 0; sz < z; ++sz) { + UIntType y1 = + rewind_find(last, sz, m-1) ^ rewind_find(last, sz, n-1); + if(y1 & (static_cast<UIntType>(1) << (w-1))) { + y1 = ((y1 ^ a) << 1) | 1; + } else { + y1 = y1 << 1; + } + *(last - sz) = (y0 & upper_mask) | (y1 & lower_mask); + y0 = y1; + } + } + + /** + * Given a pointer to the last element of the rewind array, + * and the current size of the rewind array, finds an element + * relative to the next available slot in the rewind array. + */ + UIntType + rewind_find(UIntType* last, std::size_t size, std::size_t j) const + { + std::size_t index = (j + n - size + n - 1) % n; + if(index < n - size) { + return x[index]; + } else { + return *(last - (n - 1 - index)); + } + } + + /// \endcond + + // state representation: next output is o(x(i)) + // x[0] ... x[k] x[k+1] ... x[n-1] represents + // x(i-k) ... x(i) x(i+1) ... x(i-k+n-1) + + UIntType x[n]; + std::size_t i; +}; + +/// \cond show_private + +#ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION +// A definition is required even for integral static constants +#define BOOST_RANDOM_MT_DEFINE_CONSTANT(type, name) \ +template<class UIntType, std::size_t w, std::size_t n, std::size_t m, \ + std::size_t r, UIntType a, std::size_t u, UIntType d, std::size_t s, \ + UIntType b, std::size_t t, UIntType c, std::size_t l, UIntType f> \ +const type mersenne_twister_engine<UIntType,w,n,m,r,a,u,d,s,b,t,c,l,f>::name +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, word_size); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, state_size); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, shift_size); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, mask_bits); +BOOST_RANDOM_MT_DEFINE_CONSTANT(UIntType, xor_mask); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, tempering_u); +BOOST_RANDOM_MT_DEFINE_CONSTANT(UIntType, tempering_d); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, tempering_s); +BOOST_RANDOM_MT_DEFINE_CONSTANT(UIntType, tempering_b); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, tempering_t); +BOOST_RANDOM_MT_DEFINE_CONSTANT(UIntType, tempering_c); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, tempering_l); +BOOST_RANDOM_MT_DEFINE_CONSTANT(UIntType, initialization_multiplier); +BOOST_RANDOM_MT_DEFINE_CONSTANT(UIntType, default_seed); +BOOST_RANDOM_MT_DEFINE_CONSTANT(UIntType, parameter_a); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, output_u ); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, output_s); +BOOST_RANDOM_MT_DEFINE_CONSTANT(UIntType, output_b); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, output_t); +BOOST_RANDOM_MT_DEFINE_CONSTANT(UIntType, output_c); +BOOST_RANDOM_MT_DEFINE_CONSTANT(std::size_t, output_l); +BOOST_RANDOM_MT_DEFINE_CONSTANT(bool, has_fixed_range); +#undef BOOST_RANDOM_MT_DEFINE_CONSTANT +#endif + +template<class UIntType, + std::size_t w, std::size_t n, std::size_t m, std::size_t r, + UIntType a, std::size_t u, UIntType d, std::size_t s, + UIntType b, std::size_t t, + UIntType c, std::size_t l, UIntType f> +void +mersenne_twister_engine<UIntType,w,n,m,r,a,u,d,s,b,t,c,l,f>::twist() +{ + const UIntType upper_mask = (~static_cast<UIntType>(0)) << r; + const UIntType lower_mask = ~upper_mask; + + const std::size_t unroll_factor = 6; + const std::size_t unroll_extra1 = (n-m) % unroll_factor; + const std::size_t unroll_extra2 = (m-1) % unroll_factor; + + // split loop to avoid costly modulo operations + { // extra scope for MSVC brokenness w.r.t. for scope + for(std::size_t j = 0; j < n-m-unroll_extra1; j++) { + UIntType y = (x[j] & upper_mask) | (x[j+1] & lower_mask); + x[j] = x[j+m] ^ (y >> 1) ^ ((x[j+1]&1) * a); + } + } + { + for(std::size_t j = n-m-unroll_extra1; j < n-m; j++) { + UIntType y = (x[j] & upper_mask) | (x[j+1] & lower_mask); + x[j] = x[j+m] ^ (y >> 1) ^ ((x[j+1]&1) * a); + } + } + { + for(std::size_t j = n-m; j < n-1-unroll_extra2; j++) { + UIntType y = (x[j] & upper_mask) | (x[j+1] & lower_mask); + x[j] = x[j-(n-m)] ^ (y >> 1) ^ ((x[j+1]&1) * a); + } + } + { + for(std::size_t j = n-1-unroll_extra2; j < n-1; j++) { + UIntType y = (x[j] & upper_mask) | (x[j+1] & lower_mask); + x[j] = x[j-(n-m)] ^ (y >> 1) ^ ((x[j+1]&1) * a); + } + } + // last iteration + UIntType y = (x[n-1] & upper_mask) | (x[0] & lower_mask); + x[n-1] = x[m-1] ^ (y >> 1) ^ ((x[0]&1) * a); + i = 0; +} +/// \endcond + +template<class UIntType, + std::size_t w, std::size_t n, std::size_t m, std::size_t r, + UIntType a, std::size_t u, UIntType d, std::size_t s, + UIntType b, std::size_t t, + UIntType c, std::size_t l, UIntType f> +inline typename +mersenne_twister_engine<UIntType,w,n,m,r,a,u,d,s,b,t,c,l,f>::result_type +mersenne_twister_engine<UIntType,w,n,m,r,a,u,d,s,b,t,c,l,f>::operator()() +{ + if(i == n) + twist(); + // Step 4 + UIntType z = x[i]; + ++i; + z ^= ((z >> u) & d); + z ^= ((z << s) & b); + z ^= ((z << t) & c); + z ^= (z >> l); + return z; +} + +/** + * The specializations \mt11213b and \mt19937 are from + * + * @blockquote + * "Mersenne Twister: A 623-dimensionally equidistributed + * uniform pseudo-random number generator", Makoto Matsumoto + * and Takuji Nishimura, ACM Transactions on Modeling and + * Computer Simulation: Special Issue on Uniform Random Number + * Generation, Vol. 8, No. 1, January 1998, pp. 3-30. + * @endblockquote + */ +typedef mersenne_twister_engine<uint32_t,32,351,175,19,0xccab8ee7, + 11,0xffffffff,7,0x31b6ab00,15,0xffe50000,17,1812433253> mt11213b; + +/** + * The specializations \mt11213b and \mt19937 are from + * + * @blockquote + * "Mersenne Twister: A 623-dimensionally equidistributed + * uniform pseudo-random number generator", Makoto Matsumoto + * and Takuji Nishimura, ACM Transactions on Modeling and + * Computer Simulation: Special Issue on Uniform Random Number + * Generation, Vol. 8, No. 1, January 1998, pp. 3-30. + * @endblockquote + */ +typedef mersenne_twister_engine<uint32_t,32,624,397,31,0x9908b0df, + 11,0xffffffff,7,0x9d2c5680,15,0xefc60000,18,1812433253> mt19937; + +#if !defined(BOOST_NO_INT64_T) && !defined(BOOST_NO_INTEGRAL_INT64_T) +typedef mersenne_twister_engine<uint64_t,64,312,156,31, + UINT64_C(0xb5026f5aa96619e9),29,UINT64_C(0x5555555555555555),17, + UINT64_C(0x71d67fffeda60000),37,UINT64_C(0xfff7eee000000000),43, + UINT64_C(6364136223846793005)> mt19937_64; +#endif + +/// \cond show_deprecated + +template<class UIntType, + int w, int n, int m, int r, + UIntType a, int u, std::size_t s, + UIntType b, int t, + UIntType c, int l, UIntType v> +class mersenne_twister : + public mersenne_twister_engine<UIntType, + w, n, m, r, a, u, ~(UIntType)0, s, b, t, c, l, 1812433253> +{ + typedef mersenne_twister_engine<UIntType, + w, n, m, r, a, u, ~(UIntType)0, s, b, t, c, l, 1812433253> base_type; +public: + mersenne_twister() {} + BOOST_RANDOM_DETAIL_GENERATOR_CONSTRUCTOR(mersenne_twister, Gen, gen) + { seed(gen); } + BOOST_RANDOM_DETAIL_ARITHMETIC_CONSTRUCTOR(mersenne_twister, UIntType, val) + { seed(val); } + template<class It> + mersenne_twister(It& first, It last) : base_type(first, last) {} + void seed() { base_type::seed(); } + BOOST_RANDOM_DETAIL_GENERATOR_SEED(mersenne_twister, Gen, gen) + { + detail::generator_seed_seq<Gen> seq(gen); + base_type::seed(seq); + } + BOOST_RANDOM_DETAIL_ARITHMETIC_SEED(mersenne_twister, UIntType, val) + { base_type::seed(val); } + template<class It> + void seed(It& first, It last) { base_type::seed(first, last); } +}; + +/// \endcond + +} // namespace random + +using random::mt11213b; +using random::mt19937; +using random::mt19937_64; + +} // namespace boost + +BOOST_RANDOM_PTR_HELPER_SPEC(boost::mt11213b) +BOOST_RANDOM_PTR_HELPER_SPEC(boost::mt19937) +BOOST_RANDOM_PTR_HELPER_SPEC(boost::mt19937_64) + +#endif // BOOST_RANDOM_MERSENNE_TWISTER_HPP