ceph/src/boost/boost/compute/algorithm/partition_copy.hpp

   1 //---------------------------------------------------------------------------//
   2 // Copyright (c) 2013 Kyle Lutz <kyle.r.lutz@gmail.com>
   3 //
   4 // Distributed under the Boost Software License, Version 1.0
   5 // See accompanying file LICENSE_1_0.txt or copy at
   6 // http://www.boost.org/LICENSE_1_0.txt
   7 //
   8 // See http://boostorg.github.com/compute for more information.
   9 //---------------------------------------------------------------------------//
  10
  11 #ifndef BOOST_COMPUTE_ALGORITHM_PARTITION_COPY_HPP
  12 #define BOOST_COMPUTE_ALGORITHM_PARTITION_COPY_HPP
  13
  14 #include <boost/compute/system.hpp>
  15 #include <boost/compute/functional.hpp>
  16 #include <boost/compute/command_queue.hpp>
  17 #include <boost/compute/algorithm/copy_if.hpp>
  18
  19 namespace boost {
  20 namespace compute {
  21
  22 /// Copies all of the elements in the range [\p first, \p last) for which
  23 /// \p predicate returns \c true to the range beginning at \p first_true
  24 /// and all of the elements for which \p predicate returns \c false to
  25 /// the range beginning at \p first_false.
  26 ///
  27 /// Space complexity: \Omega(2n)
  28 ///
  29 /// \see partition()
  30 template<class InputIterator,
  31          class OutputIterator1,
  32          class OutputIterator2,
  33          class UnaryPredicate>
  34 inline std::pair<OutputIterator1, OutputIterator2>
  35 partition_copy(InputIterator first,
  36                InputIterator last,
  37                OutputIterator1 first_true,
  38                OutputIterator2 first_false,
  39                UnaryPredicate predicate,
  40                command_queue &queue = system::default_queue())
  41 {
  42     // copy true values
  43     OutputIterator1 last_true =
  44         ::boost::compute::copy_if(first,
  45                                   last,
  46                                   first_true,
  47                                   predicate,
  48                                   queue);
  49
  50     // copy false values
  51     OutputIterator2 last_false =
  52         ::boost::compute::copy_if(first,
  53                                   last,
  54                                   first_false,
  55                                   not1(predicate),
  56                                   queue);
  57
  58     // return iterators to the end of the true and the false ranges
  59     return std::make_pair(last_true, last_false);
  60 }
  61
  62 } // end compute namespace
  63 } // end boost namespace
  64
  65 #endif // BOOST_COMPUTE_ALGORITHM_PARTITION_COPY_HPP