ceph/src/boost/boost/geometry/index/detail/algorithms/diff_abs.hpp

   1 // Boost.Geometry Index
   2 //
   3 // Abs of difference
   4 //
   5 // Copyright (c) 2011-2013 Adam Wulkiewicz, Lodz, Poland.
   6 //
   7 // Use, modification and distribution is subject to the Boost Software License,
   8 // Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
   9 // http://www.boost.org/LICENSE_1_0.txt)
  10
  11 #ifndef BOOST_GEOMETRY_INDEX_DETAIL_ALGORITHMS_DIFF_ABS_HPP
  12 #define BOOST_GEOMETRY_INDEX_DETAIL_ALGORITHMS_DIFF_ABS_HPP
  13
  14 namespace boost { namespace geometry { namespace index { namespace detail {
  15
  16 template <typename T>
  17 inline T diff_abs_dispatch(T const& v1, T const& v2, boost::mpl::bool_<true> const& /*is_integral*/)
  18 {
  19     return v1 < v2 ? v2 - v1 : v1 - v2;
  20 }
  21
  22 template <typename T>
  23 inline T diff_abs_dispatch(T const& v1, T const& v2, boost::mpl::bool_<false> const& /*is_integral*/)
  24 {
  25     return ::fabs(v1 - v2);
  26 }
  27
  28 template <typename T>
  29 inline T diff_abs(T const& v1, T const& v2)
  30 {
  31     typedef boost::mpl::bool_<
  32         boost::is_integral<T>::value
  33     > is_integral;
  34     return diff_abs_dispatch(v1, v2, is_integral());
  35 }
  36
  37 }}}} // namespace boost::geometry::index::detail
  38
  39 #endif // BOOST_GEOMETRY_INDEX_DETAIL_ALGORITHMS_DIFF_ABS_HPP