epoc32/include/stdapis/boost/random/subtract_with_carry.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/subtract_with_carry.hpp	Tue Mar 16 16:12:26 2010 +0000
     1.3 @@ -0,0 +1,445 @@
     1.4 +/* boost random/subtract_with_carry.hpp header file
     1.5 + *
     1.6 + * Copyright Jens Maurer 2002
     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: subtract_with_carry.hpp,v 1.24 2005/05/21 15:57:00 dgregor Exp $
    1.14 + *
    1.15 + * Revision history
    1.16 + *  2002-03-02  created
    1.17 + */
    1.18 +
    1.19 +#ifndef BOOST_RANDOM_SUBTRACT_WITH_CARRY_HPP
    1.20 +#define BOOST_RANDOM_SUBTRACT_WITH_CARRY_HPP
    1.21 +
    1.22 +#include <cmath>
    1.23 +#include <iostream>
    1.24 +#include <algorithm>     // std::equal
    1.25 +#include <stdexcept>
    1.26 +#include <cmath>         // std::pow
    1.27 +#include <boost/config.hpp>
    1.28 +#include <boost/limits.hpp>
    1.29 +#include <boost/cstdint.hpp>
    1.30 +#include <boost/static_assert.hpp>
    1.31 +#include <boost/detail/workaround.hpp>
    1.32 +#include <boost/random/linear_congruential.hpp>
    1.33 +
    1.34 +
    1.35 +namespace boost {
    1.36 +namespace random {
    1.37 +
    1.38 +#if BOOST_WORKAROUND(_MSC_FULL_VER, BOOST_TESTED_AT(13102292)) && BOOST_MSVC > 1300
    1.39 +#  define BOOST_RANDOM_EXTRACT_SWC_01
    1.40 +#endif
    1.41 +
    1.42 +#if defined(__APPLE_CC__) && defined(__GNUC__) && (__GNUC__ == 3) && (__GNUC_MINOR__ <= 3)
    1.43 +#  define BOOST_RANDOM_EXTRACT_SWC_01
    1.44 +#endif
    1.45 +
    1.46 +# ifdef BOOST_RANDOM_EXTRACT_SWC_01
    1.47 +namespace detail
    1.48 +{
    1.49 +  template <class IStream, class SubtractWithCarry, class RealType>
    1.50 +  void extract_subtract_with_carry_01(
    1.51 +      IStream& is
    1.52 +      , SubtractWithCarry& f
    1.53 +      , RealType& carry
    1.54 +      , RealType* x
    1.55 +      , RealType modulus)
    1.56 +  {
    1.57 +    RealType value;
    1.58 +    for(unsigned int j = 0; j < f.long_lag; ++j) {
    1.59 +      is >> value >> std::ws;
    1.60 +      x[j] = value / modulus;
    1.61 +    }
    1.62 +    is >> value >> std::ws;
    1.63 +    carry = value / modulus;
    1.64 +  }
    1.65 +}
    1.66 +# endif 
    1.67 +// subtract-with-carry generator
    1.68 +// Marsaglia and Zaman
    1.69 +
    1.70 +template<class IntType, IntType m, unsigned int s, unsigned int r,
    1.71 +  IntType val>
    1.72 +class subtract_with_carry
    1.73 +{
    1.74 +public:
    1.75 +  typedef IntType result_type;
    1.76 +  BOOST_STATIC_CONSTANT(bool, has_fixed_range = true);
    1.77 +  BOOST_STATIC_CONSTANT(result_type, min_value = 0);
    1.78 +  BOOST_STATIC_CONSTANT(result_type, max_value = m-1);
    1.79 +  BOOST_STATIC_CONSTANT(result_type, modulus = m);
    1.80 +  BOOST_STATIC_CONSTANT(unsigned int, long_lag = r);
    1.81 +  BOOST_STATIC_CONSTANT(unsigned int, short_lag = s);
    1.82 +
    1.83 +  subtract_with_carry() {
    1.84 +    // MSVC fails BOOST_STATIC_ASSERT with std::numeric_limits at class scope
    1.85 +#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
    1.86 +    BOOST_STATIC_ASSERT(std::numeric_limits<result_type>::is_signed);
    1.87 +    BOOST_STATIC_ASSERT(std::numeric_limits<result_type>::is_integer);
    1.88 +#endif
    1.89 +    seed();
    1.90 +  }
    1.91 +  explicit subtract_with_carry(uint32_t value) { seed(value); }
    1.92 +  template<class Generator>
    1.93 +  explicit subtract_with_carry(Generator & gen) { seed(gen); }
    1.94 +  template<class It> subtract_with_carry(It& first, It last) { seed(first,last); }
    1.95 +
    1.96 +  // compiler-generated copy ctor and assignment operator are fine
    1.97 +
    1.98 +  void seed(uint32_t value = 19780503u)
    1.99 +  {
   1.100 +    random::linear_congruential<int32_t, 40014, 0, 2147483563, 0> intgen(value);
   1.101 +    seed(intgen);
   1.102 +  }
   1.103 +
   1.104 +  // For GCC, moving this function out-of-line prevents inlining, which may
   1.105 +  // reduce overall object code size.  However, MSVC does not grok
   1.106 +  // out-of-line template member functions.
   1.107 +  template<class Generator>
   1.108 +  void seed(Generator & gen)
   1.109 +  {
   1.110 +    // I could have used std::generate_n, but it takes "gen" by value
   1.111 +    for(unsigned int j = 0; j < long_lag; ++j)
   1.112 +      x[j] = gen() % modulus;
   1.113 +    carry = (x[long_lag-1] == 0);
   1.114 +    k = 0;
   1.115 +  }
   1.116 +
   1.117 +  template<class It>
   1.118 +  void seed(It& first, It last)
   1.119 +  {
   1.120 +    unsigned int j;
   1.121 +    for(j = 0; j < long_lag && first != last; ++j, ++first)
   1.122 +      x[j] = *first % modulus;
   1.123 +    if(first == last && j < long_lag)
   1.124 +      throw std::invalid_argument("subtract_with_carry::seed");
   1.125 +    carry = (x[long_lag-1] == 0);
   1.126 +    k = 0;
   1.127 +   }
   1.128 +
   1.129 +  result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return min_value; }
   1.130 +  result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const { return max_value; }
   1.131 +
   1.132 +  result_type operator()()
   1.133 +  {
   1.134 +    int short_index = k - short_lag;
   1.135 +    if(short_index < 0)
   1.136 +      short_index += long_lag;
   1.137 +    IntType delta;
   1.138 +    if (x[short_index] >= x[k] + carry) {
   1.139 +      // x(n) >= 0
   1.140 +      delta =  x[short_index] - (x[k] + carry);
   1.141 +      carry = 0;
   1.142 +    } else {
   1.143 +      // x(n) < 0
   1.144 +      delta = modulus - x[k] - carry + x[short_index];
   1.145 +      carry = 1;
   1.146 +    }
   1.147 +    x[k] = delta;
   1.148 +    ++k;
   1.149 +    if(k >= long_lag)
   1.150 +      k = 0;
   1.151 +    return delta;
   1.152 +  }
   1.153 +
   1.154 +public:
   1.155 +  static bool validation(result_type x) { return x == val; }
   1.156 +  
   1.157 +#ifndef BOOST_NO_OPERATORS_IN_NAMESPACE
   1.158 +
   1.159 +#ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
   1.160 +  template<class CharT, class Traits>
   1.161 +  friend std::basic_ostream<CharT,Traits>&
   1.162 +  operator<<(std::basic_ostream<CharT,Traits>& os,
   1.163 +             const subtract_with_carry& f)
   1.164 +  {
   1.165 +    for(unsigned int j = 0; j < f.long_lag; ++j)
   1.166 +      os << f.compute(j) << " ";
   1.167 +    os << f.carry << " ";
   1.168 +    return os;
   1.169 +  }
   1.170 +
   1.171 +  template<class CharT, class Traits>
   1.172 +  friend std::basic_istream<CharT,Traits>&
   1.173 +  operator>>(std::basic_istream<CharT,Traits>& is, subtract_with_carry& f)
   1.174 +  {
   1.175 +    for(unsigned int j = 0; j < f.long_lag; ++j)
   1.176 +      is >> f.x[j] >> std::ws;
   1.177 +    is >> f.carry >> std::ws;
   1.178 +    f.k = 0;
   1.179 +    return is;
   1.180 +  }
   1.181 +#endif
   1.182 +
   1.183 +  friend bool operator==(const subtract_with_carry& x, const subtract_with_carry& y)
   1.184 +  {
   1.185 +    for(unsigned int j = 0; j < r; ++j)
   1.186 +      if(x.compute(j) != y.compute(j))
   1.187 +        return false;
   1.188 +    return true;
   1.189 +  }
   1.190 +
   1.191 +  friend bool operator!=(const subtract_with_carry& x, const subtract_with_carry& y)
   1.192 +  { return !(x == y); }
   1.193 +#else
   1.194 +  // Use a member function; Streamable concept not supported.
   1.195 +  bool operator==(const subtract_with_carry& rhs) const
   1.196 +  {
   1.197 +    for(unsigned int j = 0; j < r; ++j)
   1.198 +      if(compute(j) != rhs.compute(j))
   1.199 +        return false;
   1.200 +    return true;
   1.201 +  }
   1.202 +
   1.203 +  bool operator!=(const subtract_with_carry& rhs) const
   1.204 +  { return !(*this == rhs); }
   1.205 +#endif
   1.206 +
   1.207 +private:
   1.208 +  // returns x(i-r+index), where index is in 0..r-1
   1.209 +  IntType compute(unsigned int index) const
   1.210 +  {
   1.211 +    return x[(k+index) % long_lag];
   1.212 +  }
   1.213 +
   1.214 +  // state representation; next output (state) is x(i)
   1.215 +  //   x[0]  ... x[k] x[k+1] ... x[long_lag-1]     represents
   1.216 +  //  x(i-k) ... x(i) x(i+1) ... x(i-k+long_lag-1)
   1.217 +  // speed: base: 20-25 nsec
   1.218 +  // ranlux_4: 230 nsec, ranlux_7: 430 nsec, ranlux_14: 810 nsec
   1.219 +  // This state representation makes operator== and save/restore more
   1.220 +  // difficult, because we've already computed "too much" and thus
   1.221 +  // have to undo some steps to get at x(i-r) etc.
   1.222 +
   1.223 +  // state representation: next output (state) is x(i)
   1.224 +  //   x[0]  ... x[k] x[k+1]          ... x[long_lag-1]     represents
   1.225 +  //  x(i-k) ... x(i) x(i-long_lag+1) ... x(i-k-1)
   1.226 +  // speed: base 28 nsec
   1.227 +  // ranlux_4: 370 nsec, ranlux_7: 688 nsec, ranlux_14: 1343 nsec
   1.228 +  IntType x[long_lag];
   1.229 +  unsigned int k;
   1.230 +  int carry;
   1.231 +};
   1.232 +
   1.233 +#ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION
   1.234 +//  A definition is required even for integral static constants
   1.235 +template<class IntType, IntType m, unsigned int s, unsigned int r, IntType val>
   1.236 +const bool subtract_with_carry<IntType, m, s, r, val>::has_fixed_range;
   1.237 +template<class IntType, IntType m, unsigned int s, unsigned int r, IntType val>
   1.238 +const IntType subtract_with_carry<IntType, m, s, r, val>::min_value;
   1.239 +template<class IntType, IntType m, unsigned int s, unsigned int r, IntType val>
   1.240 +const IntType subtract_with_carry<IntType, m, s, r, val>::max_value;
   1.241 +template<class IntType, IntType m, unsigned int s, unsigned int r, IntType val>
   1.242 +const IntType subtract_with_carry<IntType, m, s, r, val>::modulus;
   1.243 +template<class IntType, IntType m, unsigned int s, unsigned int r, IntType val>
   1.244 +const unsigned int subtract_with_carry<IntType, m, s, r, val>::long_lag;
   1.245 +template<class IntType, IntType m, unsigned int s, unsigned int r, IntType val>
   1.246 +const unsigned int subtract_with_carry<IntType, m, s, r, val>::short_lag;
   1.247 +#endif
   1.248 +
   1.249 +
   1.250 +// use a floating-point representation to produce values in [0..1)
   1.251 +template<class RealType, int w, unsigned int s, unsigned int r, int val=0>
   1.252 +class subtract_with_carry_01
   1.253 +{
   1.254 +public:
   1.255 +  typedef RealType result_type;
   1.256 +  BOOST_STATIC_CONSTANT(bool, has_fixed_range = false);
   1.257 +  BOOST_STATIC_CONSTANT(int, word_size = w);
   1.258 +  BOOST_STATIC_CONSTANT(unsigned int, long_lag = r);
   1.259 +  BOOST_STATIC_CONSTANT(unsigned int, short_lag = s);
   1.260 +
   1.261 +#ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
   1.262 +  BOOST_STATIC_ASSERT(!std::numeric_limits<result_type>::is_integer);
   1.263 +#endif
   1.264 +
   1.265 +  subtract_with_carry_01() { init_modulus(); seed(); }
   1.266 +  explicit subtract_with_carry_01(uint32_t value)
   1.267 +  { init_modulus(); seed(value);   }
   1.268 +  template<class It> subtract_with_carry_01(It& first, It last)
   1.269 +  { init_modulus(); seed(first,last); }
   1.270 +
   1.271 +private:
   1.272 +  void init_modulus()
   1.273 +  {
   1.274 +#ifndef BOOST_NO_STDC_NAMESPACE
   1.275 +    // allow for Koenig lookup
   1.276 +    using std::pow;
   1.277 +#endif
   1.278 +    _modulus = pow(RealType(2), word_size);
   1.279 +  }
   1.280 +
   1.281 +public:
   1.282 +  // compiler-generated copy ctor and assignment operator are fine
   1.283 +
   1.284 +  void seed(uint32_t value = 19780503u)
   1.285 +  {
   1.286 +#ifndef BOOST_NO_STDC_NAMESPACE
   1.287 +    // allow for Koenig lookup
   1.288 +    using std::fmod;
   1.289 +#endif
   1.290 +    random::linear_congruential<int32_t, 40014, 0, 2147483563, 0> gen(value);
   1.291 +    unsigned long array[(w+31)/32 * long_lag];
   1.292 +    for(unsigned int j = 0; j < sizeof(array)/sizeof(unsigned long); ++j)
   1.293 +      array[j] = gen();
   1.294 +    unsigned long * start = array;
   1.295 +    seed(start, array + sizeof(array)/sizeof(unsigned long));
   1.296 +  }
   1.297 +
   1.298 +  template<class It>
   1.299 +  void seed(It& first, It last)
   1.300 +  {
   1.301 +#ifndef BOOST_NO_STDC_NAMESPACE
   1.302 +    // allow for Koenig lookup
   1.303 +    using std::fmod;
   1.304 +    using std::pow;
   1.305 +#endif
   1.306 +    unsigned long mask = ~((~0u) << (w%32));   // now lowest (w%32) bits set
   1.307 +    RealType two32 = pow(RealType(2), 32);
   1.308 +    unsigned int j;
   1.309 +    for(j = 0; j < long_lag && first != last; ++j) {
   1.310 +      x[j] = RealType(0);
   1.311 +      for(int i = 0; i < w/32 && first != last; ++i, ++first)
   1.312 +        x[j] += *first / pow(two32,i+1);
   1.313 +      if(first != last && mask != 0) {
   1.314 +        x[j] += fmod((*first & mask) / _modulus, RealType(1));
   1.315 +        ++first;
   1.316 +      }
   1.317 +    }
   1.318 +    if(first == last && j < long_lag)
   1.319 +      throw std::invalid_argument("subtract_with_carry_01::seed");
   1.320 +    carry = (x[long_lag-1] ? 0 : 1 / _modulus);
   1.321 +    k = 0;
   1.322 +  }
   1.323 +
   1.324 +  result_type min BOOST_PREVENT_MACRO_SUBSTITUTION () const { return result_type(0); }
   1.325 +  result_type max BOOST_PREVENT_MACRO_SUBSTITUTION () const { return result_type(1); }
   1.326 +
   1.327 +  result_type operator()()
   1.328 +  {
   1.329 +    int short_index = k - short_lag;
   1.330 +    if(short_index < 0)
   1.331 +      short_index += long_lag;
   1.332 +    RealType delta = x[short_index] - x[k] - carry;
   1.333 +    if(delta < 0) {
   1.334 +      delta += RealType(1);
   1.335 +      carry = RealType(1)/_modulus;
   1.336 +    } else {
   1.337 +      carry = 0;
   1.338 +    }
   1.339 +    x[k] = delta;
   1.340 +    ++k;
   1.341 +    if(k >= long_lag)
   1.342 +      k = 0;
   1.343 +    return delta;
   1.344 +  }
   1.345 +
   1.346 +  static bool validation(result_type x)
   1.347 +  { return x == val/pow(RealType(2), word_size); }
   1.348 +  
   1.349 +#ifndef BOOST_NO_OPERATORS_IN_NAMESPACE
   1.350 +
   1.351 +#ifndef BOOST_NO_MEMBER_TEMPLATE_FRIENDS
   1.352 +  template<class CharT, class Traits>
   1.353 +  friend std::basic_ostream<CharT,Traits>&
   1.354 +  operator<<(std::basic_ostream<CharT,Traits>& os,
   1.355 +             const subtract_with_carry_01& f)
   1.356 +  {
   1.357 +#ifndef BOOST_NO_STDC_NAMESPACE
   1.358 +    // allow for Koenig lookup
   1.359 +    using std::pow;
   1.360 +#endif
   1.361 +    std::ios_base::fmtflags oldflags = os.flags(os.dec | os.fixed | os.left); 
   1.362 +    for(unsigned int j = 0; j < f.long_lag; ++j)
   1.363 +      os << (f.compute(j) * f._modulus) << " ";
   1.364 +    os << (f.carry * f._modulus);
   1.365 +    os.flags(oldflags);
   1.366 +    return os;
   1.367 +  }
   1.368 +
   1.369 +  template<class CharT, class Traits>
   1.370 +  friend std::basic_istream<CharT,Traits>&
   1.371 +  operator>>(std::basic_istream<CharT,Traits>& is, subtract_with_carry_01& f)
   1.372 +  {
   1.373 +# ifdef BOOST_RANDOM_EXTRACT_SWC_01
   1.374 +      detail::extract_subtract_with_carry_01(is, f, f.carry, f.x, f._modulus);
   1.375 +# else
   1.376 +    // MSVC (up to 7.1) and Borland (up to 5.64) don't handle the template type
   1.377 +    // parameter "RealType" available from the class template scope, so use
   1.378 +    // the member typedef
   1.379 +    typename subtract_with_carry_01::result_type value;
   1.380 +    for(unsigned int j = 0; j < long_lag; ++j) {
   1.381 +      is >> value >> std::ws;
   1.382 +      f.x[j] = value / f._modulus;
   1.383 +    }
   1.384 +    is >> value >> std::ws;
   1.385 +    f.carry = value / f._modulus;
   1.386 +# endif 
   1.387 +    f.k = 0;
   1.388 +    return is;
   1.389 +  }
   1.390 +#endif
   1.391 +
   1.392 +  friend bool operator==(const subtract_with_carry_01& x,
   1.393 +                         const subtract_with_carry_01& y)
   1.394 +  {
   1.395 +    for(unsigned int j = 0; j < r; ++j)
   1.396 +      if(x.compute(j) != y.compute(j))
   1.397 +        return false;
   1.398 +    return true;
   1.399 +  }
   1.400 +
   1.401 +  friend bool operator!=(const subtract_with_carry_01& x,
   1.402 +                         const subtract_with_carry_01& y)
   1.403 +  { return !(x == y); }
   1.404 +#else
   1.405 +  // Use a member function; Streamable concept not supported.
   1.406 +  bool operator==(const subtract_with_carry_01& rhs) const
   1.407 +  { 
   1.408 +    for(unsigned int j = 0; j < r; ++j)
   1.409 +      if(compute(j) != rhs.compute(j))
   1.410 +        return false;
   1.411 +    return true;
   1.412 +  }
   1.413 +
   1.414 +  bool operator!=(const subtract_with_carry_01& rhs) const
   1.415 +  { return !(*this == rhs); }
   1.416 +#endif
   1.417 +
   1.418 +private:
   1.419 +  RealType compute(unsigned int index) const;
   1.420 +  unsigned int k;
   1.421 +  RealType carry;
   1.422 +  RealType x[long_lag];
   1.423 +  RealType _modulus;
   1.424 +};
   1.425 +
   1.426 +#ifndef BOOST_NO_INCLASS_MEMBER_INITIALIZATION
   1.427 +//  A definition is required even for integral static constants
   1.428 +template<class RealType, int w, unsigned int s, unsigned int r, int val>
   1.429 +const bool subtract_with_carry_01<RealType, w, s, r, val>::has_fixed_range;
   1.430 +template<class RealType, int w, unsigned int s, unsigned int r, int val>
   1.431 +const int subtract_with_carry_01<RealType, w, s, r, val>::word_size;
   1.432 +template<class RealType, int w, unsigned int s, unsigned int r, int val>
   1.433 +const unsigned int subtract_with_carry_01<RealType, w, s, r, val>::long_lag;
   1.434 +template<class RealType, int w, unsigned int s, unsigned int r, int val>
   1.435 +const unsigned int subtract_with_carry_01<RealType, w, s, r, val>::short_lag;
   1.436 +#endif
   1.437 +
   1.438 +template<class RealType, int w, unsigned int s, unsigned int r, int val>
   1.439 +RealType subtract_with_carry_01<RealType, w, s, r, val>::compute(unsigned int index) const
   1.440 +{
   1.441 +  return x[(k+index) % long_lag];
   1.442 +}
   1.443 +
   1.444 +
   1.445 +} // namespace random
   1.446 +} // namespace boost
   1.447 +
   1.448 +#endif // BOOST_RANDOM_SUBTRACT_WITH_CARRY_HPP