MaxLoc#

Specific implementation of ReducerConcept storing the maximum value

Header File: Kokkos_Core.hpp

Usage:

MaxLoc<T,I,S>::value_type result;
parallel_reduce(N,Functor,MaxLoc<T,I,S>(result));

Synopsis#

template<class Scalar, class Index, class Space>
class MaxLoc{
 public:
   typedef MaxLoc reducer;
   typedef ValLocScalar<typename std::remove_cv<Scalar>::type,
                        typename std::remove_cv<Index>::type > value_type;
   typedef Kokkos::View<value_type, Space> result_view_type;
   
   KOKKOS_INLINE_FUNCTION
   void join(value_type& dest, const value_type& src)  const

   KOKKOS_INLINE_FUNCTION
   void init( value_type& val)  const;

   KOKKOS_INLINE_FUNCTION
   value_type& reference() const;

   KOKKOS_INLINE_FUNCTION
   result_view_type view() const;

   KOKKOS_INLINE_FUNCTION
   MaxLoc(value_type& value_);

   KOKKOS_INLINE_FUNCTION
   MaxLoc(const result_view_type& value_);
};

Public Class Members#

Typedefs#

  • reducer: The self type.

  • value_type: The reduction scalar type (specialization of ValLocScalar)

  • result_view_type: A Kokkos::View referencing the reduction result

Constructors#

  • MaxLoc(value_type& result)

    Constructs a reducer which references a local variable as its result location.

  • MaxLoc(const result_view_type result)

    Constructs a reducer which references a specific view as its result location.

Functions#

  • void join(value_type& dest, const value_type& src)  const;

    Store maximum with index of src and dest into dest: dest = (src.val > dest.val) ? src : dest;.

  • void init( value_type& val)  const;

    Initialize val.val using the Kokkos::reduction_identity::max() method. The default implementation sets val=<TYPE>_MIN.

    Initialize val.loc using the Kokkos::reduction_identity::min() method. The default implementation sets val=<TYPE>_MAX.

  • value_type& reference() const;

    Returns a reference to the result provided in class constructor.

  • result_view_type view() const;

    Returns a view of the result place provided in class constructor.

Additional Information#

  • MaxLoc<T,I,S>::value_type is Specialization of ValLocScalar on non-const T and non-const I

  • MaxLoc<T,I,S>::result_view_type is Kokkos::View<T,S,Kokkos::MemoryTraits<Kokkos::Unmanaged>>. Note that the S (memory space) must be the same as the space where the result resides.

  • Requires: Scalar has operator = and operator > defined. Kokkos::reduction_identity<Scalar>::max() is a valid expression.

  • Requires: Index has operator = defined. Kokkos::reduction_identity<Index>::min() is a valid expression.

  • In order to use MaxLoc with a custom type of either Scalar or Index, a template specialization of Kokkos::reduction_identity<CustomType> must be defined. See Built-In Reducers with Custom Scalar Types for details