diff -r 000000000000 -r bde4ae8d615e os/ossrv/ossrv_pub/boost_apis/boost/random/mersenne_twister.hpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/os/ossrv/ossrv_pub/boost_apis/boost/random/mersenne_twister.hpp Fri Jun 15 03:10:57 2012 +0200 @@ -0,0 +1,302 @@ +/* boost random/mersenne_twister.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: mersenne_twister.hpp,v 1.20 2005/07/21 22:04:31 jmaurer Exp $ + * + * Revision history + * 2001-02-18 moved to individual header files + */ + +#ifndef BOOST_RANDOM_MERSENNE_TWISTER_HPP +#define BOOST_RANDOM_MERSENNE_TWISTER_HPP + +#include +#include // std::copy +#include +#include +#include +#include +#include +#include +#include +#include +#include + +namespace boost { +namespace random { + +// http://www.math.keio.ac.jp/matumoto/emt.html +template +class mersenne_twister +{ +public: + typedef UIntType result_type; + BOOST_STATIC_CONSTANT(int, word_size = w); + BOOST_STATIC_CONSTANT(int, state_size = n); + BOOST_STATIC_CONSTANT(int, shift_size = m); + BOOST_STATIC_CONSTANT(int, mask_bits = r); + BOOST_STATIC_CONSTANT(UIntType, parameter_a = a); + BOOST_STATIC_CONSTANT(int, output_u = u); + BOOST_STATIC_CONSTANT(int, output_s = s); + BOOST_STATIC_CONSTANT(UIntType, output_b = b); + BOOST_STATIC_CONSTANT(int, output_t = t); + BOOST_STATIC_CONSTANT(UIntType, output_c = c); + BOOST_STATIC_CONSTANT(int, output_l = l); + + BOOST_STATIC_CONSTANT(bool, has_fixed_range = false); + + mersenne_twister() { seed(); } + +#if defined(__SUNPRO_CC) && (__SUNPRO_CC <= 0x520) + // Work around overload resolution problem (Gennadiy E. Rozental) + explicit mersenne_twister(const UIntType& value) +#else + explicit mersenne_twister(UIntType value) +#endif + { seed(value); } + template mersenne_twister(It& first, It last) { seed(first,last); } + + template + explicit mersenne_twister(Generator & gen) { seed(gen); } + + // compiler-generated copy ctor and assignment operator are fine + + void seed() { seed(UIntType(5489)); } + +#if defined(__SUNPRO_CC) && (__SUNPRO_CC <= 0x520) + // Work around overload resolution problem (Gennadiy E. Rozental) + void seed(const UIntType& value) +#else + void seed(UIntType value) +#endif + { + // 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 = ~0u; + 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] = (1812433253UL * (x[i-1] ^ (x[i-1] >> (w-2))) + i) & mask; + } + } + + // For GCC, moving this function out-of-line prevents inlining, which may + // reduce overall object code size. However, MSVC does not grok + // out-of-line definitions of member function templates. + template + void seed(Generator & gen) + { +#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS + BOOST_STATIC_ASSERT(!std::numeric_limits::is_signed); +#endif + // I could have used std::generate_n, but it takes "gen" by value + for(int j = 0; j < n; j++) + x[j] = gen(); + i = n; + } + + template + void seed(It& first, It last) + { + int j; + for(j = 0; j < n && first != last; ++j, ++first) + x[j] = *first; + i = n; + if(first == last && j < n) + throw std::invalid_argument("mersenne_twister::seed"); + } + + result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return 0; } + result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const + { + // avoid "left shift count >= with of type" warning + result_type res = 0; + for(int i = 0; i < w; ++i) + res |= (1u << i); + return res; + } + + result_type operator()(); + static bool validation(result_type v) { return val == v; } + +#ifndef BOOST_NO_OPERATORS_IN_NAMESPACE + +#ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS + template + friend std::basic_ostream& + operator<<(std::basic_ostream& os, const mersenne_twister& mt) + { + for(int j = 0; j < mt.state_size; ++j) + os << mt.compute(j) << " "; + return os; + } + + template + friend std::basic_istream& + operator>>(std::basic_istream& is, mersenne_twister& mt) + { + for(int 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 + + friend bool operator==(const mersenne_twister& x, const mersenne_twister& y) + { + for(int j = 0; j < state_size; ++j) + if(x.compute(j) != y.compute(j)) + return false; + return true; + } + + friend bool operator!=(const mersenne_twister& x, const mersenne_twister& y) + { return !(x == y); } +#else + // Use a member function; Streamable concept not supported. + bool operator==(const mersenne_twister& rhs) const + { + for(int j = 0; j < state_size; ++j) + if(compute(j) != rhs.compute(j)) + return false; + return true; + } + + bool operator!=(const mersenne_twister& rhs) const + { return !(*this == rhs); } +#endif + +private: + // returns x(i-n+index), where index is in 0..n-1 + UIntType compute(unsigned int index) const + { + // equivalent to (i-n+index) % 2n, but doesn't produce negative numbers + return x[ (i + n + index) % (2*n) ]; + } + void twist(int block); + + // state representation: next output is o(x(i)) + // x[0] ... x[k] x[k+1] ... x[n-1] x[n] ... x[2*n-1] represents + // x(i-k) ... x(i) x(i+1) ... x(i-k+n-1) x(i-k-n) ... x[i(i-k-1)] + // The goal is to always have x(i-n) ... x(i-1) available for + // operator== and save/restore. + + UIntType x[2*n]; + int i; +}; + +#ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION +// A definition is required even for integral static constants +template +const bool mersenne_twister::has_fixed_range; +template +const int mersenne_twister::state_size; +template +const int mersenne_twister::shift_size; +template +const int mersenne_twister::mask_bits; +template +const UIntType mersenne_twister::parameter_a; +template +const int mersenne_twister::output_u; +template +const int mersenne_twister::output_s; +template +const UIntType mersenne_twister::output_b; +template +const int mersenne_twister::output_t; +template +const UIntType mersenne_twister::output_c; +template +const int mersenne_twister::output_l; +#endif + +template +void mersenne_twister::twist(int block) +{ + const UIntType upper_mask = (~0u) << r; + const UIntType lower_mask = ~upper_mask; + + if(block == 0) { + for(int j = n; j < 2*n; j++) { + UIntType y = (x[j-n] & upper_mask) | (x[j-(n-1)] & lower_mask); + x[j] = x[j-(n-m)] ^ (y >> 1) ^ (y&1 ? a : 0); + } + } else if (block == 1) { + // split loop to avoid costly modulo operations + { // extra scope for MSVC brokenness w.r.t. for scope + for(int j = 0; j < n-m; j++) { + UIntType y = (x[j+n] & upper_mask) | (x[j+n+1] & lower_mask); + x[j] = x[j+n+m] ^ (y >> 1) ^ (y&1 ? a : 0); + } + } + + for(int j = n-m; j < n-1; j++) { + UIntType y = (x[j+n] & upper_mask) | (x[j+n+1] & lower_mask); + x[j] = x[j-(n-m)] ^ (y >> 1) ^ (y&1 ? a : 0); + } + // last iteration + UIntType y = (x[2*n-1] & upper_mask) | (x[0] & lower_mask); + x[n-1] = x[m-1] ^ (y >> 1) ^ (y&1 ? a : 0); + i = 0; + } +} + +template +inline typename mersenne_twister::result_type +mersenne_twister::operator()() +{ + if(i == n) + twist(0); + else if(i >= 2*n) + twist(1); + // Step 4 + UIntType z = x[i]; + ++i; + z ^= (z >> u); + z ^= ((z << s) & b); + z ^= ((z << t) & c); + z ^= (z >> l); + return z; +} + +} // namespace random + + +typedef random::mersenne_twister mt11213b; + +// validation by experiment from mt19937.c +typedef random::mersenne_twister mt19937; + +} // namespace boost + +BOOST_RANDOM_PTR_HELPER_SPEC(boost::mt19937) + +#endif // BOOST_RANDOM_MERSENNE_TWISTER_HPP