Tpetra_Details_getEntryOnHost.hpp

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#ifndef TPETRA_DETAILS_GETENTRYONHOST_HPP
#define TPETRA_DETAILS_GETENTRYONHOST_HPP


#include "TpetraCore_config.h"
#include "Kokkos_Core.hpp"

namespace Tpetra {
namespace Details {

template<class ViewType,
         class IndexType>
typename ViewType::non_const_value_type
getEntryOnHost (const ViewType& x,
                const IndexType ind)
{
  static_assert (ViewType::Rank == 1, "x must be a rank-1 Kokkos::View.");
  // Get a 0-D subview of the entry of the array, and copy to host scalar.
  typename ViewType::non_const_value_type val;
  Kokkos::deep_copy(val, Kokkos::subview(x, ind));
  return val;
}

} // namespace Details
} // namespace Tpetra

#endif // TPETRA_DETAILS_GETENTRYONHOST_HPP