ceph/src/boost/boost/histogram/axis/boolean.hpp

   1 // Copyright Hans Dembinski 2020
   2 //
   3 // Distributed under the Boost Software License, Version 1.0.
   4 // (See accompanying file LICENSE_1_0.txt
   5 // or copy at http://www.boost.org/LICENSE_1_0.txt)
   6
   7 #ifndef BOOST_HISTOGRAM_AXIS_BOOLEAN_HPP
   8 #define BOOST_HISTOGRAM_AXIS_BOOLEAN_HPP
   9
  10 #include <boost/core/nvp.hpp>
  11 #include <boost/histogram/axis/iterator.hpp>
  12 #include <boost/histogram/axis/metadata_base.hpp>
  13 #include <boost/histogram/axis/option.hpp>
  14 #include <boost/histogram/detail/relaxed_equal.hpp>
  15 #include <boost/histogram/detail/replace_type.hpp>
  16 #include <boost/histogram/fwd.hpp>
  17 #include <string>
  18
  19 namespace boost {
  20 namespace histogram {
  21 namespace axis {
  22
  23 /**
  24   Discrete axis for boolean data.
  25
  26   Binning is a pass-though operation with zero cost, making this the
  27   fastest possible axis. The axis has no internal state apart from the
  28   optional metadata state. The axis has no under- and overflow bins.
  29   It cannot grow and cannot be reduced.
  30
  31   @tparam MetaData type to store meta data.
  32  */
  33 template <class MetaData>
  34 class boolean : public iterator_mixin<boolean<MetaData>>,
  35                 public metadata_base_t<MetaData> {
  36   using value_type = bool;
  37   using metadata_base = metadata_base_t<MetaData>;
  38   using metadata_type = typename metadata_base::metadata_type;
  39
  40 public:
  41   /** Construct a boolean axis.
  42    *
  43    * \param meta     description of the axis.
  44    */
  45   explicit boolean(metadata_type meta = {}) : metadata_base(std::move(meta)) {}
  46
  47   /// Return index for value argument.
  48   index_type index(value_type x) const noexcept { return static_cast<index_type>(x); }
  49
  50   /// Return value for index argument.
  51   value_type value(index_type i) const noexcept { return static_cast<value_type>(i); }
  52
  53   /// Return bin for index argument.
  54   value_type bin(index_type i) const noexcept { return value(i); }
  55
  56   /// Returns the number of bins, without over- or underflow.
  57   index_type size() const noexcept { return 2; }
  58
  59   /// Whether the axis is inclusive (see axis::traits::is_inclusive).
  60   static constexpr bool inclusive() noexcept { return true; }
  61
  62   /// Returns the options.
  63   static constexpr unsigned options() noexcept { return option::none_t::value; }
  64
  65   template <class M>
  66   bool operator==(const boolean<M>& o) const noexcept {
  67     return detail::relaxed_equal{}(this->metadata(), o.metadata());
  68   }
  69
  70   template <class M>
  71   bool operator!=(const boolean<M>& o) const noexcept {
  72     return !operator==(o);
  73   }
  74
  75   template <class Archive>
  76   void serialize(Archive& ar, unsigned /* version */) {
  77     ar& make_nvp("meta", this->metadata());
  78   }
  79
  80 private:
  81   template <class M>
  82   friend class boolean;
  83 };
  84
  85 #if __cpp_deduction_guides >= 201606
  86
  87 boolean()->boolean<null_type>;
  88
  89 template <class M>
  90 boolean(M) -> boolean<detail::replace_type<std::decay_t<M>, const char*, std::string>>;
  91
  92 #endif
  93
  94 } // namespace axis
  95 } // namespace histogram
  96 } // namespace boost
  97
  98 #endif // BOOST_HISTOGRAM_AXIS_BOOLEAN_HPP