count_if

Header File: Kokkos_StdAlgorithms.hpp

namespace Kokkos{
namespace Experimental{

template <class ExecutionSpace, class IteratorType, class Predicate>
typename IteratorType::difference_type count_if(const ExecutionSpace& exespace,
                                                IteratorType first,
                                                IteratorType last,                   (1)
                                                Predicate pred);


template <class ExecutionSpace, class IteratorType, class Predicate>
typename IteratorType::difference_type count_if(const std::string& label,
                                                const ExecutionSpace& exespace,
                                                IteratorType first,                  (2)
                                                IteratorType last,
                                                Predicate pred);

template <class ExecutionSpace, class DataType, class... Properties,
          class Predicate>
auto count_if(const ExecutionSpace& exespace,
              const ::Kokkos::View<DataType, Properties...>& view,                   (3)
              Predicate pred);

template <class ExecutionSpace, class DataType, class... Properties,
          class Predicate>
auto count_if(const std::string& label, const ExecutionSpace& exespace,
              const ::Kokkos::View<DataType, Properties...>& view,                   (4)
              Predicate pred);

} //end namespace Experimental
} //end namespace Kokkos

Description

Returns the number of elements in the range [first,last) (1,2) or in view (3,4) for which pred is true.

Parameters and Requirements

• exespace:

  • execution space instance

• label:

  • 1: The default string is “Kokkos::count_if_iterator_api_default”

  • 3: The default string is “Kokkos::count_if_view_api_default”

• first, last:

  • range of elements to search in

  • must be random access iterators, e.g., returned from Kokkos::Experimental::(c)begin/(c)end

  • must represent a valid range, i.e., last >= first (this condition is checked in debug mode)

  • must be accessible from exespace

• view:

  • must be rank-1, and have LayoutLeft, LayoutRight, or LayoutStride

  • must be accessible from exespace

• pred is similar to equal