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- /* 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.
- *
- * $Id$
- *
- * Revision history
- * 2013-10-14 fixed some warnings with Wshadow (mgaunard)
- * 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>
- #include <boost/random/detail/polynomial.hpp>
- #include <boost/random/detail/disable_warnings.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;
- }
- normalize_state();
- }
- /**
- * 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;
- normalize_state();
- }
- /** 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;
- normalize_state();
- }
- /** Returns the smallest value that the generator can produce. */
- static BOOST_CONSTEXPR result_type min BOOST_PREVENT_MACRO_SUBSTITUTION ()
- { return 0; }
- /** Returns the largest value that the generator can produce. */
- static BOOST_CONSTEXPR 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)
- {
- #ifndef BOOST_RANDOM_MERSENNE_TWISTER_DISCARD_THRESHOLD
- #define BOOST_RANDOM_MERSENNE_TWISTER_DISCARD_THRESHOLD 10000000
- #endif
- if(z > BOOST_RANDOM_MERSENNE_TWISTER_DISCARD_THRESHOLD) {
- discard_many(z);
- } else {
- 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;
- }
- }
- /**
- * Converts an arbitrary array into a valid generator state.
- * First we normalize x[0], so that it contains the same
- * value we would get by running the generator forwards
- * and then in reverse. (The low order r bits are redundant).
- * Then, if the state consists of all zeros, we set the
- * high order bit of x[0] to 1. This function only needs to
- * be called by seed, since the state transform preserves
- * this relationship.
- */
- void normalize_state()
- {
- 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;
- }
- x[0] = (x[0] & upper_mask) | (y0 & lower_mask);
- // fix up the state if it's all zeroes.
- for(std::size_t j = 0; j < n; ++j) {
- if(x[j] != 0) return;
- }
- x[0] = static_cast<UIntType>(1) << (w-1);
- }
- /**
- * 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));
- }
- }
- /**
- * Optimized algorithm for large jumps.
- *
- * Hiroshi Haramoto, Makoto Matsumoto, and Pierre L'Ecuyer. 2008.
- * A Fast Jump Ahead Algorithm for Linear Recurrences in a Polynomial
- * Space. In Proceedings of the 5th international conference on
- * Sequences and Their Applications (SETA '08).
- * DOI=10.1007/978-3-540-85912-3_26
- */
- void discard_many(boost::uintmax_t z)
- {
- // Compute the minimal polynomial, phi(t)
- // This depends only on the transition function,
- // which is constant. The characteristic
- // polynomial is the same as the minimal
- // polynomial for a maximum period generator
- // (which should be all specializations of
- // mersenne_twister.) Even if it weren't,
- // the characteristic polynomial is guaranteed
- // to be a multiple of the minimal polynomial,
- // which is good enough.
- detail::polynomial phi = get_characteristic_polynomial();
- // calculate g(t) = t^z % phi(t)
- detail::polynomial g = mod_pow_x(z, phi);
- // h(s_0, t) = \sum_{i=0}^{2k-1}o(s_i)t^{2k-i-1}
- detail::polynomial h;
- const std::size_t num_bits = w*n - r;
- for(std::size_t j = 0; j < num_bits * 2; ++j) {
- // Yes, we're advancing the generator state
- // here, but it doesn't matter because
- // we're going to overwrite it completely
- // in reconstruct_state.
- if(i >= n) twist();
- h[2*num_bits - j - 1] = x[i++] & UIntType(1);
- }
- // g(t)h(s_0, t)
- detail::polynomial gh = g * h;
- detail::polynomial result;
- for(std::size_t j = 0; j <= num_bits; ++j) {
- result[j] = gh[2*num_bits - j - 1];
- }
- reconstruct_state(result);
- }
- static detail::polynomial get_characteristic_polynomial()
- {
- const std::size_t num_bits = w*n - r;
- detail::polynomial helper;
- helper[num_bits - 1] = 1;
- mersenne_twister_engine tmp;
- tmp.reconstruct_state(helper);
- // Skip the first num_bits elements, since we
- // already know what they are.
- for(std::size_t j = 0; j < num_bits; ++j) {
- if(tmp.i >= n) tmp.twist();
- if(j == num_bits - 1)
- assert((tmp.x[tmp.i] & 1) == 1);
- else
- assert((tmp.x[tmp.i] & 1) == 0);
- ++tmp.i;
- }
- detail::polynomial phi;
- phi[num_bits] = 1;
- detail::polynomial next_bits = tmp.as_polynomial(num_bits);
- for(std::size_t j = 0; j < num_bits; ++j) {
- int val = next_bits[j] ^ phi[num_bits-j-1];
- phi[num_bits-j-1] = val;
- if(val) {
- for(std::size_t k = j + 1; k < num_bits; ++k) {
- phi[num_bits-k-1] ^= next_bits[k-j-1];
- }
- }
- }
- return phi;
- }
- detail::polynomial as_polynomial(std::size_t size) {
- detail::polynomial result;
- for(std::size_t j = 0; j < size; ++j) {
- if(i >= n) twist();
- result[j] = x[i++] & UIntType(1);
- }
- return result;
- }
- void reconstruct_state(const detail::polynomial& p)
- {
- const UIntType upper_mask = (~static_cast<UIntType>(0)) << r;
- const UIntType lower_mask = ~upper_mask;
- const std::size_t num_bits = w*n - r;
- for(std::size_t j = num_bits - n + 1; j <= num_bits; ++j)
- x[j % n] = p[j];
- UIntType y0 = 0;
- for(std::size_t j = num_bits + 1; j >= n - 1; --j) {
- UIntType y1 = x[j % n] ^ x[(j + m) % n];
- if(p[j - n + 1])
- y1 = (y1 ^ a) << UIntType(1) | UIntType(1);
- else
- y1 = y1 << UIntType(1);
- x[(j + 1) % n] = (y0 & upper_mask) | (y1 & lower_mask);
- y0 = y1;
- }
- i = 0;
- }
- /// \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)
- #include <boost/random/detail/enable_warnings.hpp>
- #endif // BOOST_RANDOM_MERSENNE_TWISTER_HPP
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