review fixes

change to a floating point number
remove unused variables

.github/workflows/docker_workflow.yml

@@ -50,4 +50,5 @@ jobs:
           mpirun -n 3 ./build/src/example1
           mpirun -n 3 ./build/src/example2
           mpirun -n 3 ./build/src/example3
+          mpirun -n 3 ./build/src/example4
           mpirun -n 3 ./build/src/example5

scripts/build_run.sh

@@ -13,4 +13,5 @@ cmake --build build -j
 mpirun -n 2 ./build/src/example1
 mpirun -n 2 ./build/src/example2
 mpirun -n 2 ./build/src/example3
+mpirun -n 2 ./build/src/example4
 mpirun -n 2 ./build/src/example5

src/example5.cpp

@@ -7,15 +7,13 @@
 
 namespace mhp = dr::mhp;
 
-using T = uint16_t;
+using T = float;
 using MDA = dr::mhp::distributed_mdarray<T, 2>;
 
+/* 2d stencil - simple operation on multi-dimensional array */
 int main() {
-#ifdef SYCL_LANGUAGE_VERSION
   mhp::init(sycl::default_selector_v);
-#else
-  mhp::init();
-#endif
+
   std::size_t arr_size = 4;
   std::size_t radius = 1;
   std::array slice_starts{radius, radius};
@@ -29,15 +27,13 @@ int main() {
 
   auto in = dr::mhp::views::submdspan(a.view(), slice_starts, slice_ends);
   auto out = dr::mhp::views::submdspan(b.view(), slice_starts, slice_ends);
-  auto in_array = &a;
-  auto out_array = &b;
 
   auto mdspan_stencil_op = [](auto &&v) {
     auto [in, out] = v;
     out(0, 0) = (in(-1, 0) + in(0, -1) + in(0, 0) + in(0, 1) + in(1, 0)) / 4;
   };
 
-  mhp::halo(*in_array).exchange();
+  mhp::halo(a).exchange();
   mhp::stencil_for_each(mdspan_stencil_op, in, out);
 
   if (mhp::rank() == 0) {