epoc32/include/stdapis/boost/random/mersenne_twister.hpp
branchSymbian2
changeset 2 2fe1408b6811
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/epoc32/include/stdapis/boost/random/mersenne_twister.hpp	Tue Mar 16 16:12:26 2010 +0000
     1.3 @@ -0,0 +1,302 @@
     1.4 +/* boost random/mersenne_twister.hpp header file
     1.5 + *
     1.6 + * Copyright Jens Maurer 2000-2001
     1.7 + * Distributed under the Boost Software License, Version 1.0. (See
     1.8 + * accompanying file LICENSE_1_0.txt or copy at
     1.9 + * http://www.boost.org/LICENSE_1_0.txt)
    1.10 + *
    1.11 + * See http://www.boost.org for most recent version including documentation.
    1.12 + *
    1.13 + * $Id: mersenne_twister.hpp,v 1.20 2005/07/21 22:04:31 jmaurer Exp $
    1.14 + *
    1.15 + * Revision history
    1.16 + *  2001-02-18  moved to individual header files
    1.17 + */
    1.18 +
    1.19 +#ifndef BOOST_RANDOM_MERSENNE_TWISTER_HPP
    1.20 +#define BOOST_RANDOM_MERSENNE_TWISTER_HPP
    1.21 +
    1.22 +#include <iostream>
    1.23 +#include <algorithm>     // std::copy
    1.24 +#include <stdexcept>
    1.25 +#include <boost/config.hpp>
    1.26 +#include <boost/limits.hpp>
    1.27 +#include <boost/static_assert.hpp>
    1.28 +#include <boost/integer_traits.hpp>
    1.29 +#include <boost/cstdint.hpp>
    1.30 +#include <boost/random/linear_congruential.hpp>
    1.31 +#include <boost/detail/workaround.hpp>
    1.32 +#include <boost/random/detail/ptr_helper.hpp>
    1.33 +
    1.34 +namespace boost {
    1.35 +namespace random {
    1.36 +
    1.37 +// http://www.math.keio.ac.jp/matumoto/emt.html
    1.38 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
    1.39 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
    1.40 +class mersenne_twister
    1.41 +{
    1.42 +public:
    1.43 +  typedef UIntType result_type;
    1.44 +  BOOST_STATIC_CONSTANT(int, word_size = w);
    1.45 +  BOOST_STATIC_CONSTANT(int, state_size = n);
    1.46 +  BOOST_STATIC_CONSTANT(int, shift_size = m);
    1.47 +  BOOST_STATIC_CONSTANT(int, mask_bits = r);
    1.48 +  BOOST_STATIC_CONSTANT(UIntType, parameter_a = a);
    1.49 +  BOOST_STATIC_CONSTANT(int, output_u = u);
    1.50 +  BOOST_STATIC_CONSTANT(int, output_s = s);
    1.51 +  BOOST_STATIC_CONSTANT(UIntType, output_b = b);
    1.52 +  BOOST_STATIC_CONSTANT(int, output_t = t);
    1.53 +  BOOST_STATIC_CONSTANT(UIntType, output_c = c);
    1.54 +  BOOST_STATIC_CONSTANT(int, output_l = l);
    1.55 +
    1.56 +  BOOST_STATIC_CONSTANT(bool, has_fixed_range = false);
    1.57 +  
    1.58 +  mersenne_twister() { seed(); }
    1.59 +
    1.60 +#if defined(__SUNPRO_CC) && (__SUNPRO_CC <= 0x520)
    1.61 +  // Work around overload resolution problem (Gennadiy E. Rozental)
    1.62 +  explicit mersenne_twister(const UIntType& value)
    1.63 +#else
    1.64 +  explicit mersenne_twister(UIntType value)
    1.65 +#endif
    1.66 +  { seed(value); }
    1.67 +  template<class It> mersenne_twister(It& first, It last) { seed(first,last); }
    1.68 +
    1.69 +  template<class Generator>
    1.70 +  explicit mersenne_twister(Generator & gen) { seed(gen); }
    1.71 +
    1.72 +  // compiler-generated copy ctor and assignment operator are fine
    1.73 +
    1.74 +  void seed() { seed(UIntType(5489)); }
    1.75 +
    1.76 +#if defined(__SUNPRO_CC) && (__SUNPRO_CC <= 0x520)
    1.77 +  // Work around overload resolution problem (Gennadiy E. Rozental)
    1.78 +  void seed(const UIntType& value)
    1.79 +#else
    1.80 +  void seed(UIntType value)
    1.81 +#endif
    1.82 +  {
    1.83 +    // New seeding algorithm from 
    1.84 +    // http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/MT2002/emt19937ar.html
    1.85 +    // In the previous versions, MSBs of the seed affected only MSBs of the
    1.86 +    // state x[].
    1.87 +    const UIntType mask = ~0u;
    1.88 +    x[0] = value & mask;
    1.89 +    for (i = 1; i < n; i++) {
    1.90 +      // See Knuth "The Art of Computer Programming" Vol. 2, 3rd ed., page 106
    1.91 +      x[i] = (1812433253UL * (x[i-1] ^ (x[i-1] >> (w-2))) + i) & mask;
    1.92 +    }
    1.93 +  }
    1.94 +
    1.95 +  // For GCC, moving this function out-of-line prevents inlining, which may
    1.96 +  // reduce overall object code size.  However, MSVC does not grok
    1.97 +  // out-of-line definitions of member function templates.
    1.98 +  template<class Generator>
    1.99 +  void seed(Generator & gen)
   1.100 +  {
   1.101 +#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
   1.102 +    BOOST_STATIC_ASSERT(!std::numeric_limits<result_type>::is_signed);
   1.103 +#endif
   1.104 +    // I could have used std::generate_n, but it takes "gen" by value
   1.105 +    for(int j = 0; j < n; j++)
   1.106 +      x[j] = gen();
   1.107 +    i = n;
   1.108 +  }
   1.109 +
   1.110 +  template<class It>
   1.111 +  void seed(It& first, It last)
   1.112 +  {
   1.113 +    int j;
   1.114 +    for(j = 0; j < n && first != last; ++j, ++first)
   1.115 +      x[j] = *first;
   1.116 +    i = n;
   1.117 +    if(first == last && j < n)
   1.118 +      throw std::invalid_argument("mersenne_twister::seed");
   1.119 +  }
   1.120 +  
   1.121 +  result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return 0; }
   1.122 +  result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const
   1.123 +  {
   1.124 +    // avoid "left shift count >= with of type" warning
   1.125 +    result_type res = 0;
   1.126 +    for(int i = 0; i < w; ++i)
   1.127 +      res |= (1u << i);
   1.128 +    return res;
   1.129 +  }
   1.130 +
   1.131 +  result_type operator()();
   1.132 +  static bool validation(result_type v) { return val == v; }
   1.133 +
   1.134 +#ifndef BOOST_NO_OPERATORS_IN_NAMESPACE
   1.135 +
   1.136 +#ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
   1.137 +  template<class CharT, class Traits>
   1.138 +  friend std::basic_ostream<CharT,Traits>&
   1.139 +  operator<<(std::basic_ostream<CharT,Traits>& os, const mersenne_twister& mt)
   1.140 +  {
   1.141 +    for(int j = 0; j < mt.state_size; ++j)
   1.142 +      os << mt.compute(j) << " ";
   1.143 +    return os;
   1.144 +  }
   1.145 +
   1.146 +  template<class CharT, class Traits>
   1.147 +  friend std::basic_istream<CharT,Traits>&
   1.148 +  operator>>(std::basic_istream<CharT,Traits>& is, mersenne_twister& mt)
   1.149 +  {
   1.150 +    for(int j = 0; j < mt.state_size; ++j)
   1.151 +      is >> mt.x[j] >> std::ws;
   1.152 +    // MSVC (up to 7.1) and Borland (up to 5.64) don't handle the template
   1.153 +    // value parameter "n" available from the class template scope, so use
   1.154 +    // the static constant with the same value
   1.155 +    mt.i = mt.state_size;
   1.156 +    return is;
   1.157 +  }
   1.158 +#endif
   1.159 +
   1.160 +  friend bool operator==(const mersenne_twister& x, const mersenne_twister& y)
   1.161 +  {
   1.162 +    for(int j = 0; j < state_size; ++j)
   1.163 +      if(x.compute(j) != y.compute(j))
   1.164 +        return false;
   1.165 +    return true;
   1.166 +  }
   1.167 +
   1.168 +  friend bool operator!=(const mersenne_twister& x, const mersenne_twister& y)
   1.169 +  { return !(x == y); }
   1.170 +#else
   1.171 +  // Use a member function; Streamable concept not supported.
   1.172 +  bool operator==(const mersenne_twister& rhs) const
   1.173 +  {
   1.174 +    for(int j = 0; j < state_size; ++j)
   1.175 +      if(compute(j) != rhs.compute(j))
   1.176 +        return false;
   1.177 +    return true;
   1.178 +  }
   1.179 +
   1.180 +  bool operator!=(const mersenne_twister& rhs) const
   1.181 +  { return !(*this == rhs); }
   1.182 +#endif
   1.183 +
   1.184 +private:
   1.185 +  // returns x(i-n+index), where index is in 0..n-1
   1.186 +  UIntType compute(unsigned int index) const
   1.187 +  {
   1.188 +    // equivalent to (i-n+index) % 2n, but doesn't produce negative numbers
   1.189 +    return x[ (i + n + index) % (2*n) ];
   1.190 +  }
   1.191 +  void twist(int block);
   1.192 +
   1.193 +  // state representation: next output is o(x(i))
   1.194 +  //   x[0]  ... x[k] x[k+1] ... x[n-1]     x[n]     ... x[2*n-1]   represents
   1.195 +  //  x(i-k) ... x(i) x(i+1) ... x(i-k+n-1) x(i-k-n) ... x[i(i-k-1)]
   1.196 +  // The goal is to always have x(i-n) ... x(i-1) available for
   1.197 +  // operator== and save/restore.
   1.198 +
   1.199 +  UIntType x[2*n]; 
   1.200 +  int i;
   1.201 +};
   1.202 +
   1.203 +#ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION
   1.204 +//  A definition is required even for integral static constants
   1.205 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.206 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.207 +const bool mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::has_fixed_range;
   1.208 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.209 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.210 +const int mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::state_size;
   1.211 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.212 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.213 +const int mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::shift_size;
   1.214 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.215 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.216 +const int mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::mask_bits;
   1.217 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.218 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.219 +const UIntType mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::parameter_a;
   1.220 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.221 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.222 +const int mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::output_u;
   1.223 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.224 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.225 +const int mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::output_s;
   1.226 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.227 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.228 +const UIntType mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::output_b;
   1.229 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.230 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.231 +const int mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::output_t;
   1.232 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.233 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.234 +const UIntType mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::output_c;
   1.235 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.236 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.237 +const int mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::output_l;
   1.238 +#endif
   1.239 +
   1.240 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.241 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.242 +void mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::twist(int block)
   1.243 +{
   1.244 +  const UIntType upper_mask = (~0u) << r;
   1.245 +  const UIntType lower_mask = ~upper_mask;
   1.246 +
   1.247 +  if(block == 0) {
   1.248 +    for(int j = n; j < 2*n; j++) {
   1.249 +      UIntType y = (x[j-n] & upper_mask) | (x[j-(n-1)] & lower_mask);
   1.250 +      x[j] = x[j-(n-m)] ^ (y >> 1) ^ (y&1 ? a : 0);
   1.251 +    }
   1.252 +  } else if (block == 1) {
   1.253 +    // split loop to avoid costly modulo operations
   1.254 +    {  // extra scope for MSVC brokenness w.r.t. for scope
   1.255 +      for(int j = 0; j < n-m; j++) {
   1.256 +        UIntType y = (x[j+n] & upper_mask) | (x[j+n+1] & lower_mask);
   1.257 +        x[j] = x[j+n+m] ^ (y >> 1) ^ (y&1 ? a : 0);
   1.258 +      }
   1.259 +    }
   1.260 +    
   1.261 +    for(int j = n-m; j < n-1; j++) {
   1.262 +      UIntType y = (x[j+n] & upper_mask) | (x[j+n+1] & lower_mask);
   1.263 +      x[j] = x[j-(n-m)] ^ (y >> 1) ^ (y&1 ? a : 0);
   1.264 +    }
   1.265 +    // last iteration
   1.266 +    UIntType y = (x[2*n-1] & upper_mask) | (x[0] & lower_mask);
   1.267 +    x[n-1] = x[m-1] ^ (y >> 1) ^ (y&1 ? a : 0);
   1.268 +    i = 0;
   1.269 +  }
   1.270 +}
   1.271 +
   1.272 +template<class UIntType, int w, int n, int m, int r, UIntType a, int u,
   1.273 +  int s, UIntType b, int t, UIntType c, int l, UIntType val>
   1.274 +inline typename mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::result_type
   1.275 +mersenne_twister<UIntType,w,n,m,r,a,u,s,b,t,c,l,val>::operator()()
   1.276 +{
   1.277 +  if(i == n)
   1.278 +    twist(0);
   1.279 +  else if(i >= 2*n)
   1.280 +    twist(1);
   1.281 +  // Step 4
   1.282 +  UIntType z = x[i];
   1.283 +  ++i;
   1.284 +  z ^= (z >> u);
   1.285 +  z ^= ((z << s) & b);
   1.286 +  z ^= ((z << t) & c);
   1.287 +  z ^= (z >> l);
   1.288 +  return z;
   1.289 +}
   1.290 +
   1.291 +} // namespace random
   1.292 +
   1.293 +
   1.294 +typedef random::mersenne_twister<uint32_t,32,351,175,19,0xccab8ee7,11,
   1.295 +  7,0x31b6ab00,15,0xffe50000,17, 0xa37d3c92> mt11213b;
   1.296 +
   1.297 +// validation by experiment from mt19937.c
   1.298 +typedef random::mersenne_twister<uint32_t,32,624,397,31,0x9908b0df,11,
   1.299 +  7,0x9d2c5680,15,0xefc60000,18, 3346425566U> mt19937;
   1.300 +
   1.301 +} // namespace boost
   1.302 +
   1.303 +BOOST_RANDOM_PTR_HELPER_SPEC(boost::mt19937)
   1.304 +
   1.305 +#endif // BOOST_RANDOM_MERSENNE_TWISTER_HPP