[NL] misuse sparsity pattern for PETSc

NumLib/DOF/ComputeSparsityPattern.cpp

@@ -12,20 +12,36 @@
 #include "LocalToGlobalIndexMap.h"
 #include "MeshLib/NodeAdjacencyTable.h"
 
-namespace NumLib
+#ifdef USE_PETSC
+#include "MeshLib/NodePartitionedMesh.h"
+
+GlobalSparsityPattern computeSparsityPatternPETSc(
+    NumLib::LocalToGlobalIndexMap const& /*dof_table*/,
+    MeshLib::Mesh const& mesh)
 {
-GlobalSparsityPattern computeSparsityPattern(
-    LocalToGlobalIndexMap const& dof_table, MeshLib::Mesh const& mesh)
+    assert(dynamic_cast<MeshLib::NodePartitionedMesh const*>(&mesh));
+    auto const& npmesh =
+        *static_cast<MeshLib::NodePartitionedMesh const*>(&mesh);
+
+    auto const max_nonzeroes = npmesh.getMaximumNConnectedNodesToNode();
+
+    // The sparsity pattern is misused here in the sense that it will only
+    // contain a single value.
+    return GlobalSparsityPattern(1, max_nonzeroes);
+}
+#else
+GlobalSparsityPattern computeSparsityPatternNonPETSc(
+    NumLib::LocalToGlobalIndexMap const& dof_table, MeshLib::Mesh const& mesh)
 {
     MeshLib::NodeAdjacencyTable node_adjacency_table;
     node_adjacency_table.createTable(mesh.getNodes());
 
     // A mapping   mesh node id -> global indices
     // It acts as a cache for dof table queries.
-    std::vector<std::vector<GlobalIndexType> > global_idcs;
+    std::vector<std::vector<GlobalIndexType>> global_idcs;
 
     global_idcs.reserve(mesh.getNNodes());
-    for (std::size_t n=0; n<mesh.getNNodes(); ++n)
+    for (std::size_t n = 0; n < mesh.getNNodes(); ++n)
     {
         MeshLib::Location l(mesh.getID(), MeshLib::MeshItemType::Node, n);
         global_idcs.push_back(dof_table.getGlobalIndices(l));
@@ -34,15 +50,18 @@ GlobalSparsityPattern computeSparsityPattern(
     GlobalSparsityPattern sparsity_pattern(dof_table.dofSizeWithGhosts());
 
     // Map adjacent mesh nodes to "adjacent global indices".
-    for (std::size_t n=0; n<mesh.getNNodes(); ++n)
+    for (std::size_t n = 0; n < mesh.getNNodes(); ++n)
     {
         auto const& node_ids = node_adjacency_table.getAdjacentNodes(n);
-        for (auto an : node_ids) {
+        for (auto an : node_ids)
+        {
             auto const& row_ids = global_idcs[an];
             auto const num_components = row_ids.size();
-            for (auto r : row_ids) {
+            for (auto r : row_ids)
+            {
                 // Each component leads to an entry in the row.
-                // For the sparsity pattern only the number of entries are needed.
+                // For the sparsity pattern only the number of entries are
+                // needed.
                 sparsity_pattern[r] += num_components;
             }
         }
@@ -50,5 +69,18 @@ GlobalSparsityPattern computeSparsityPattern(
 
     return sparsity_pattern;
 }
+#endif
+
+namespace NumLib
+{
+GlobalSparsityPattern computeSparsityPattern(
+    LocalToGlobalIndexMap const& dof_table, MeshLib::Mesh const& mesh)
+{
+#ifdef USE_PETSC
+    return computeSparsityPatternPETSc(dof_table, mesh);
+#else
+    return computeSparsityPatternNonPETSc(dof_table, mesh);
+#endif
+}
 
 }