use CTAD for plan creation

examples/09_derivative/09_derivative.cpp

@@ -105,7 +105,7 @@ void analytical_solution(RealView1DType& x, RealView1DType& y,
   auto h_x = Kokkos::create_mirror_view_and_copy(Kokkos::HostSpace(), x);
   auto h_y = Kokkos::create_mirror_view_and_copy(Kokkos::HostSpace(), y);
 
-  // Initialize field
+  // Compute the analytical solution on host
   const int nx = dudxy.extent(2), ny = dudxy.extent(1), nz = dudxy.extent(0);
   auto h_dudxy = Kokkos::create_mirror_view(dudxy);
   for (int iz = 0; iz < nz; iz++) {
@@ -134,12 +134,6 @@ void compute_derivative(const int nx, const int ny, const int nz,
   using ComplexView2D = View2D<Kokkos::complex<double>>;
   using ComplexView3D = View3D<Kokkos::complex<double>>;
 
-  // KokkosFFT plan types
-  using ForwardPlanType =
-      KokkosFFT::Plan<execution_space, RealView3D, ComplexView3D, 2>;
-  using BackwardPlanType =
-      KokkosFFT::Plan<execution_space, ComplexView3D, RealView3D, 2>;
-
   // Declare grids
   RealView1D x("x", nx), y("y", ny);
   ComplexView2D ikx("ikx", ny, nx / 2 + 1), iky("iky", ny, nx / 2 + 1);
@@ -164,10 +158,11 @@ void compute_derivative(const int nx, const int ny, const int nz,
                        point2D_type{{ny, nx / 2 + 1}},
                        tile2D_type{{TILE0, TILE1}});
 
-  ForwardPlanType r2c_plan(exec, u, u_hat, KokkosFFT::Direction::forward,
+  // kokkos-fft plans
+  KokkosFFT::Plan r2c_plan(exec, u, u_hat, KokkosFFT::Direction::forward,
+                           KokkosFFT::axis_type<2>({-2, -1}));
+  KokkosFFT::Plan c2r_plan(exec, u_hat, u, KokkosFFT::Direction::backward,
                            KokkosFFT::axis_type<2>({-2, -1}));
-  BackwardPlanType c2r_plan(exec, u_hat, u, KokkosFFT::Direction::backward,
-                            KokkosFFT::axis_type<2>({-2, -1}));
 
   // Start computation
   Kokkos::Timer timer;