Merge branch 'splines-linear-problem-periodic-band2' into lapack-backend

CExA-project · Jun 17, 2024 · d35d9c5 · d35d9c5
2 parents cc28f25 + 9b5fd29
commit d35d9c5
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Showing 2 changed files with 18 additions and 15 deletions.
diff --git a/include/ddc/kernels/splines/splines_linear_problem_maker.hpp b/include/ddc/kernels/splines/splines_linear_problem_maker.hpp
@@ -107,7 +107,7 @@ class SplinesLinearProblemMaker
      * a periodic band matrix.
      *
      * It simply calls make_new_block_matrix_with_band_main_block with bottom_size being
-     * max(kl, ku) (except if the alloation would be higher than instantiating a SplinesLinearProblemDense).
+     * max(kl, ku) (except if the allocation would be higher than instantiating a SplinesLinearProblemDense).
      *
      * @tparam the Kokkos::ExecutionSpace on which matrix-related operation will be performed.
      * @param n The size of one of the dimensions of the whole square matrix.
@@ -124,8 +124,10 @@ class SplinesLinearProblemMaker
             int const ku,
             bool const pds)
     {
+        assert(kl < n);
+        assert(ku < n);
         int const bottom_size = std::max(kl, ku);
-        int const top_size = std::max(0, n - bottom_size);
+        int const top_size = n - bottom_size;
 
         if (bottom_size * (n + top_size) + (2 * kl + ku + 1) * top_size >= n * n) {
             return std::make_unique<SplinesLinearProblemDense<ExecSpace>>(n);

diff --git a/tests/splines/matrix.cpp b/tests/splines/matrix.cpp
@@ -416,23 +416,24 @@ TEST_P(MatrixSizesFixture, PeriodicBand)
 {
     auto const [N, k] = GetParam();
 
-    // Build a non-symmetric full-rank band matrix
-    for (std::ptrdiff_t s(-k); s < (std::ptrdiff_t)k + 1; ++s) {
-        if (s == 0)
-            continue;
-
+    // Build a full-rank periodic band matrix permuted in such a way the band is shifted
+    for (std::ptrdiff_t s(-k + k / 2 + 1); s < static_cast<std::ptrdiff_t>(k - k / 2); ++s) {
+        std::cout << s;
         std::unique_ptr<ddc::detail::SplinesLinearProblem<Kokkos::DefaultExecutionSpace>> matrix
                 = ddc::detail::SplinesLinearProblemMaker::make_new_periodic_band_matrix<
-                        Kokkos::DefaultExecutionSpace>(N, k - s, k + s, false);
+                        Kokkos::DefaultExecutionSpace>(
+                        N,
+                        static_cast<std::ptrdiff_t>(k - s),
+                        k + s,
+                        false);
         for (std::size_t i(0); i < N; ++i) {
             for (std::size_t j(0); j < N; ++j) {
-                int diag = ddc::detail::modulo((int)(j - i), (int)N);
-                if (diag == s || diag == (std::ptrdiff_t)N + s) {
-                    matrix->set_element(i, j, 0.5);
-                } else if (
-                        diag <= s + (std::ptrdiff_t)k
-                        || diag >= (std::ptrdiff_t)N + s - (std::ptrdiff_t)k) {
-                    matrix->set_element(i, j, -1.0 / k);
+                std::ptrdiff_t diag = ddc::detail::
+                        modulo(static_cast<std::ptrdiff_t>(j - i), static_cast<std::ptrdiff_t>(N));
+                if (diag == s || diag == N + s) {
+                    matrix->set_element(i, j, 2.0 * k + 1);
+                } else if (diag <= s + k || diag >= N + s - k) {
+                    matrix->set_element(i, j, -1.);
                 }
             }
         }