ceph/src/boost/boost/numeric/interval/utility.hpp

   1 /* Boost interval/utility.hpp template implementation file
   2  *
   3  * Copyright 2000 Jens Maurer
   4  * Copyright 2002-2003 Hervé Brönnimann, Guillaume Melquiond, Sylvain Pion
   5  *
   6  * Distributed under the Boost Software License, Version 1.0.
   7  * (See accompanying file LICENSE_1_0.txt or
   8  * copy at http://www.boost.org/LICENSE_1_0.txt)
   9  */
  10
  11 #ifndef BOOST_NUMERIC_INTERVAL_UTILITY_HPP
  12 #define BOOST_NUMERIC_INTERVAL_UTILITY_HPP
  13
  14 #include <boost/config.hpp>
  15 #include <boost/numeric/interval/detail/interval_prototype.hpp>
  16 #include <boost/numeric/interval/detail/test_input.hpp>
  17 #include <boost/numeric/interval/detail/bugs.hpp>
  18 #include <algorithm>
  19 #include <utility>
  20
  21 /*
  22  * Implementation of simple functions
  23  */
  24
  25 namespace boost {
  26 namespace numeric {
  27
  28 /*
  29  * Utility Functions
  30  */
  31
  32 template<class T, class Policies> inline
  33 const T& lower(const interval<T, Policies>& x)
  34 {
  35   return x.lower();
  36 }
  37
  38 template<class T, class Policies> inline
  39 const T& upper(const interval<T, Policies>& x)
  40 {
  41   return x.upper();
  42 }
  43
  44 template<class T, class Policies> inline
  45 T checked_lower(const interval<T, Policies>& x)
  46 {
  47   if (empty(x)) {
  48     typedef typename Policies::checking checking;
  49     return checking::nan();
  50   }
  51   return x.lower();
  52 }
  53
  54 template<class T, class Policies> inline
  55 T checked_upper(const interval<T, Policies>& x)
  56 {
  57   if (empty(x)) {
  58     typedef typename Policies::checking checking;
  59     return checking::nan();
  60   }
  61   return x.upper();
  62 }
  63
  64 template<class T, class Policies> inline
  65 T width(const interval<T, Policies>& x)
  66 {
  67   if (interval_lib::detail::test_input(x)) return static_cast<T>(0);
  68   typename Policies::rounding rnd;
  69   return rnd.sub_up(x.upper(), x.lower());
  70 }
  71
  72 template<class T, class Policies> inline
  73 T median(const interval<T, Policies>& x)
  74 {
  75   if (interval_lib::detail::test_input(x)) {
  76     typedef typename Policies::checking checking;
  77     return checking::nan();
  78   }
  79   typename Policies::rounding rnd;
  80   return rnd.median(x.lower(), x.upper());
  81 }
  82
  83 template<class T, class Policies> inline
  84 interval<T, Policies> widen(const interval<T, Policies>& x, const T& v)
  85 {
  86   if (interval_lib::detail::test_input(x))
  87     return interval<T, Policies>::empty();
  88   typename Policies::rounding rnd;
  89   return interval<T, Policies>(rnd.sub_down(x.lower(), v),
  90                                rnd.add_up  (x.upper(), v), true);
  91 }
  92
  93 /*
  94  * Set-like operations
  95  */
  96
  97 template<class T, class Policies> inline
  98 bool empty(const interval<T, Policies>& x)
  99 {
 100   return interval_lib::detail::test_input(x);
 101 }
 102
 103 template<class T, class Policies> inline
 104 bool zero_in(const interval<T, Policies>& x)
 105 {
 106   if (interval_lib::detail::test_input(x)) return false;
 107   return (!interval_lib::user::is_pos(x.lower())) &&
 108          (!interval_lib::user::is_neg(x.upper()));
 109 }
 110
 111 template<class T, class Policies> inline
 112 bool in_zero(const interval<T, Policies>& x) // DEPRECATED
 113 {
 114   return zero_in<T, Policies>(x);
 115 }
 116
 117 template<class T, class Policies> inline
 118 bool in(const T& x, const interval<T, Policies>& y)
 119 {
 120   if (interval_lib::detail::test_input(x, y)) return false;
 121   return y.lower() <= x && x <= y.upper();
 122 }
 123
 124 template<class T, class Policies> inline
 125 bool subset(const interval<T, Policies>& x,
 126             const interval<T, Policies>& y)
 127 {
 128   if (empty(x)) return true;
 129   return !empty(y) && y.lower() <= x.lower() && x.upper() <= y.upper();
 130 }
 131
 132 template<class T, class Policies1, class Policies2> inline
 133 bool proper_subset(const interval<T, Policies1>& x,
 134                    const interval<T, Policies2>& y)
 135 {
 136   if (empty(y)) return false;
 137   if (empty(x)) return true;
 138   return y.lower() <= x.lower() && x.upper() <= y.upper() &&
 139          (y.lower() != x.lower() || x.upper() != y.upper());
 140 }
 141
 142 template<class T, class Policies1, class Policies2> inline
 143 bool overlap(const interval<T, Policies1>& x,
 144              const interval<T, Policies2>& y)
 145 {
 146   if (interval_lib::detail::test_input(x, y)) return false;
 147   return (x.lower() <= y.lower() && y.lower() <= x.upper()) ||
 148          (y.lower() <= x.lower() && x.lower() <= y.upper());
 149 }
 150
 151 template<class T, class Policies> inline
 152 bool singleton(const interval<T, Policies>& x)
 153 {
 154  return !empty(x) && x.lower() == x.upper();
 155 }
 156
 157 template<class T, class Policies1, class Policies2> inline
 158 bool equal(const interval<T, Policies1>& x, const interval<T, Policies2>& y)
 159 {
 160   if (empty(x)) return empty(y);
 161   return !empty(y) && x.lower() == y.lower() && x.upper() == y.upper();
 162 }
 163
 164 template<class T, class Policies> inline
 165 interval<T, Policies> intersect(const interval<T, Policies>& x,
 166                                 const interval<T, Policies>& y)
 167 {
 168   BOOST_USING_STD_MIN();
 169   BOOST_USING_STD_MAX();
 170   if (interval_lib::detail::test_input(x, y))
 171     return interval<T, Policies>::empty();
 172   const T& l = max BOOST_PREVENT_MACRO_SUBSTITUTION(x.lower(), y.lower());
 173   const T& u = min BOOST_PREVENT_MACRO_SUBSTITUTION(x.upper(), y.upper());
 174   if (l <= u) return interval<T, Policies>(l, u, true);
 175   else        return interval<T, Policies>::empty();
 176 }
 177
 178 template<class T, class Policies> inline
 179 interval<T, Policies> hull(const interval<T, Policies>& x,
 180                            const interval<T, Policies>& y)
 181 {
 182   BOOST_USING_STD_MIN();
 183   BOOST_USING_STD_MAX();
 184   bool bad_x = interval_lib::detail::test_input(x);
 185   bool bad_y = interval_lib::detail::test_input(y);
 186   if (bad_x)
 187     if (bad_y) return interval<T, Policies>::empty();
 188     else       return y;
 189   else
 190     if (bad_y) return x;
 191   return interval<T, Policies>(min BOOST_PREVENT_MACRO_SUBSTITUTION(x.lower(), y.lower()),
 192                                max BOOST_PREVENT_MACRO_SUBSTITUTION(x.upper(), y.upper()), true);
 193 }
 194
 195 template<class T, class Policies> inline
 196 interval<T, Policies> hull(const interval<T, Policies>& x, const T& y)
 197 {
 198   BOOST_USING_STD_MIN();
 199   BOOST_USING_STD_MAX();
 200   bool bad_x = interval_lib::detail::test_input(x);
 201   bool bad_y = interval_lib::detail::test_input<T, Policies>(y);
 202   if (bad_y)
 203     if (bad_x) return interval<T, Policies>::empty();
 204     else       return x;
 205   else
 206     if (bad_x) return interval<T, Policies>(y, y, true);
 207   return interval<T, Policies>(min BOOST_PREVENT_MACRO_SUBSTITUTION(x.lower(), y),
 208                                max BOOST_PREVENT_MACRO_SUBSTITUTION(x.upper(), y), true);
 209 }
 210
 211 template<class T, class Policies> inline
 212 interval<T, Policies> hull(const T& x, const interval<T, Policies>& y)
 213 {
 214   BOOST_USING_STD_MIN();
 215   BOOST_USING_STD_MAX();
 216   bool bad_x = interval_lib::detail::test_input<T, Policies>(x);
 217   bool bad_y = interval_lib::detail::test_input(y);
 218   if (bad_x)
 219     if (bad_y) return interval<T, Policies>::empty();
 220     else       return y;
 221   else
 222     if (bad_y) return interval<T, Policies>(x, x, true);
 223   return interval<T, Policies>(min BOOST_PREVENT_MACRO_SUBSTITUTION(x, y.lower()),
 224                                max BOOST_PREVENT_MACRO_SUBSTITUTION(x, y.upper()), true);
 225 }
 226
 227 template<class T> inline
 228 interval<T> hull(const T& x, const T& y)
 229 {
 230   return interval<T>::hull(x, y);
 231 }
 232
 233 template<class T, class Policies> inline
 234 std::pair<interval<T, Policies>, interval<T, Policies> >
 235 bisect(const interval<T, Policies>& x)
 236 {
 237   typedef interval<T, Policies> I;
 238   if (interval_lib::detail::test_input(x))
 239     return std::pair<I,I>(I::empty(), I::empty());
 240   const T m = median(x);
 241   return std::pair<I,I>(I(x.lower(), m, true), I(m, x.upper(), true));
 242 }
 243
 244 /*
 245  * Elementary functions
 246  */
 247
 248 template<class T, class Policies> inline
 249 T norm(const interval<T, Policies>& x)
 250 {
 251   if (interval_lib::detail::test_input(x)) {
 252     typedef typename Policies::checking checking;
 253     return checking::nan();
 254   }
 255   BOOST_USING_STD_MAX();
 256   return max BOOST_PREVENT_MACRO_SUBSTITUTION(static_cast<T>(-x.lower()), x.upper());
 257 }
 258
 259 template<class T, class Policies> inline
 260 interval<T, Policies> abs(const interval<T, Policies>& x)
 261 {
 262   typedef interval<T, Policies> I;
 263   if (interval_lib::detail::test_input(x))
 264     return I::empty();
 265   if (!interval_lib::user::is_neg(x.lower())) return x;
 266   if (!interval_lib::user::is_pos(x.upper())) return -x;
 267   BOOST_USING_STD_MAX();
 268   return I(static_cast<T>(0), max BOOST_PREVENT_MACRO_SUBSTITUTION(static_cast<T>(-x.lower()), x.upper()), true);
 269 }
 270
 271 template<class T, class Policies> inline
 272 interval<T, Policies> max BOOST_PREVENT_MACRO_SUBSTITUTION (const interval<T, Policies>& x,
 273                                                             const interval<T, Policies>& y)
 274 {
 275   typedef interval<T, Policies> I;
 276   if (interval_lib::detail::test_input(x, y))
 277     return I::empty();
 278   BOOST_USING_STD_MAX();
 279   return I(max BOOST_PREVENT_MACRO_SUBSTITUTION(x.lower(), y.lower()), max BOOST_PREVENT_MACRO_SUBSTITUTION(x.upper(), y.upper()), true);
 280 }
 281
 282 template<class T, class Policies> inline
 283 interval<T, Policies> max BOOST_PREVENT_MACRO_SUBSTITUTION (const interval<T, Policies>& x, const T& y)
 284 {
 285   typedef interval<T, Policies> I;
 286   if (interval_lib::detail::test_input(x, y))
 287     return I::empty();
 288   BOOST_USING_STD_MAX();
 289   return I(max BOOST_PREVENT_MACRO_SUBSTITUTION(x.lower(), y), max BOOST_PREVENT_MACRO_SUBSTITUTION(x.upper(), y), true);
 290 }
 291
 292 template<class T, class Policies> inline
 293 interval<T, Policies> max BOOST_PREVENT_MACRO_SUBSTITUTION (const T& x, const interval<T, Policies>& y)
 294 {
 295   typedef interval<T, Policies> I;
 296   if (interval_lib::detail::test_input(x, y))
 297     return I::empty();
 298   BOOST_USING_STD_MAX();
 299   return I(max BOOST_PREVENT_MACRO_SUBSTITUTION(x, y.lower()), max BOOST_PREVENT_MACRO_SUBSTITUTION(x, y.upper()), true);
 300 }
 301
 302 template<class T, class Policies> inline
 303 interval<T, Policies> min BOOST_PREVENT_MACRO_SUBSTITUTION (const interval<T, Policies>& x,
 304                                                             const interval<T, Policies>& y)
 305 {
 306   typedef interval<T, Policies> I;
 307   if (interval_lib::detail::test_input(x, y))
 308     return I::empty();
 309   BOOST_USING_STD_MIN();
 310   return I(min BOOST_PREVENT_MACRO_SUBSTITUTION(x.lower(), y.lower()), min BOOST_PREVENT_MACRO_SUBSTITUTION(x.upper(), y.upper()), true);
 311 }
 312
 313 template<class T, class Policies> inline
 314 interval<T, Policies> min BOOST_PREVENT_MACRO_SUBSTITUTION (const interval<T, Policies>& x, const T& y)
 315 {
 316   typedef interval<T, Policies> I;
 317   if (interval_lib::detail::test_input(x, y))
 318     return I::empty();
 319   BOOST_USING_STD_MIN();
 320   return I(min BOOST_PREVENT_MACRO_SUBSTITUTION(x.lower(), y), min BOOST_PREVENT_MACRO_SUBSTITUTION(x.upper(), y), true);
 321 }
 322
 323 template<class T, class Policies> inline
 324 interval<T, Policies> min BOOST_PREVENT_MACRO_SUBSTITUTION (const T& x, const interval<T, Policies>& y)
 325 {
 326   typedef interval<T, Policies> I;
 327   if (interval_lib::detail::test_input(x, y))
 328     return I::empty();
 329   BOOST_USING_STD_MIN();
 330   return I(min BOOST_PREVENT_MACRO_SUBSTITUTION(x, y.lower()), min BOOST_PREVENT_MACRO_SUBSTITUTION(x, y.upper()), true);
 331 }
 332
 333 } // namespace numeric
 334 } // namespace boost
 335
 336 #endif // BOOST_NUMERIC_INTERVAL_UTILITY_HPP