Implement InducedSubgraphView

.github/workflows/ci-matrix.yml

@@ -26,6 +26,7 @@ jobs:
   build:
     name: "${{ matrix.os }} (${{ matrix.compiler }})"
     runs-on: ${{ matrix.runner }}
+    if: github.event_name != 'pull_request' || !github.event.pull_request.draft
     strategy:
       fail-fast: false
       matrix:

include/networkit/graph/EdgeIterators.hpp

@@ -151,7 +151,7 @@ class EdgeTypeRange {
 public:
     EdgeTypeRange(const GraphType &G) : G(&G) {}
 
-    EdgeTypeRange() : G(nullptr){};
+    EdgeTypeRange() : G(nullptr) {};
 
     ~EdgeTypeRange() = default;
 

include/networkit/graph/Graph.hpp

@@ -470,8 +470,8 @@ class Graph {
      * @brief Virtual method for forInEdgesOf - overridden by GraphW for vector-based iteration
      */
     virtual void
-    forInEdgesVirtualImpl(node u, bool directed, bool weighted, bool hasEdgeIds,
-                          std::function<void(node, node, edgeweight, edgeid)> handle) const;
+    forInEdgesOfVirtualImpl(node u, bool directed, bool weighted, bool hasEdgeIds,
+                            std::function<void(node, node, edgeweight, edgeid)> handle) const;
 
     /**
      * @brief Virtual method for parallelSumForEdges - overridden by GraphW for vector-based
@@ -933,7 +933,7 @@ class Graph {
      * @return @c true if @a v exists, @c false otherwise.
      */
 
-    bool hasNode(node v) const noexcept { return (v < z) && this->exists[v]; }
+    virtual bool hasNode(node v) const noexcept { return (v < z) && this->exists[v]; }
 
     /**
      * Check if edge (u, v) exists in the graph.
@@ -942,7 +942,7 @@ class Graph {
      * @param v Second endpoint of edge.
      * @return @c true if edge exists, @c false otherwise.
      */
-    bool hasEdge(node u, node v) const;
+    virtual bool hasEdge(node u, node v) const;
 
     /**
      * @brief Virtual method for hasEdge - overridden by GraphW for vector-based graphs
@@ -1007,7 +1007,7 @@ class Graph {
      *
      * @return Weighted degree of @a u.
      */
-    edgeweight weightedDegree(node u, bool countSelfLoopsTwice = false) const;
+    virtual edgeweight weightedDegree(node u, bool countSelfLoopsTwice = false) const;
 
     /**
      * Returns the weighted in-degree of @a u.
@@ -1017,7 +1017,7 @@ class Graph {
      *
      * @return Weighted in-degree of @a v.
      */
-    edgeweight weightedDegreeIn(node u, bool countSelfLoopsTwice = false) const;
+    virtual edgeweight weightedDegreeIn(node u, bool countSelfLoopsTwice = false) const;
 
     /**
      * Returns <code>true</code> if this graph supports edge weights other
@@ -1198,7 +1198,7 @@ class Graph {
      * @return Iterator range over the neighbors of @a u.
      */
     NeighborRange<false> neighborRange(node u) const {
-        assert(exists[u]);
+        assert(hasNode(u));
         return NeighborRange<false>(*this, u);
     }
 
@@ -1212,7 +1212,7 @@ class Graph {
      */
     NeighborWeightRange<false> weightNeighborRange(node u) const {
         assert(isWeighted());
-        assert(exists[u]);
+        assert(hasNode(u));
         return NeighborWeightRange<false>(*this, u);
     }
 
@@ -1224,7 +1224,7 @@ class Graph {
      */
     NeighborRange<true> inNeighborRange(node u) const {
         assert(isDirected());
-        assert(exists[u]);
+        assert(hasNode(u));
         return NeighborRange<true>(*this, u);
     }
 
@@ -1238,7 +1238,7 @@ class Graph {
      */
     NeighborWeightRange<true> weightInNeighborRange(node u) const {
         assert(isDirected() && isWeighted());
-        assert(exists[u]);
+        assert(hasNode(u));
         return NeighborWeightRange<true>(*this, u);
     }
 
@@ -1473,7 +1473,7 @@ class Graph {
 template <typename L>
 void Graph::forNodes(L handle) const {
     for (node v = 0; v < z; ++v) {
-        if (exists[v]) {
+        if (hasNode(v)) {
             handle(v);
         }
     }
@@ -1491,7 +1491,7 @@ void Graph::parallelForNodes(L handle) const {
         // For mutable graphs, check exists
 #pragma omp parallel for
         for (omp_index v = 0; v < static_cast<omp_index>(z); ++v) {
-            if (exists[v]) {
+            if (hasNode(v)) {
                 handle(v);
             }
         }
@@ -1501,7 +1501,7 @@ void Graph::parallelForNodes(L handle) const {
 template <typename C, typename L>
 void Graph::forNodesWhile(C condition, L handle) const {
     for (node v = 0; v < z; ++v) {
-        if (exists[v]) {
+        if (hasNode(v)) {
             if (!condition()) {
                 break;
             }
@@ -1534,7 +1534,7 @@ void Graph::balancedParallelForNodes(L handle) const {
         // For mutable graphs, check exists
 #pragma omp parallel for schedule(guided)
         for (omp_index v = 0; v < static_cast<omp_index>(z); ++v) {
-            if (exists[v]) {
+            if (hasNode(v)) {
                 handle(v);
             }
         }
@@ -1544,9 +1544,9 @@ void Graph::balancedParallelForNodes(L handle) const {
 template <typename L>
 void Graph::forNodePairs(L handle) const {
     for (node u = 0; u < z; ++u) {
-        if (exists[u]) {
+        if (hasNode(u)) {
             for (node v = u + 1; v < z; ++v) {
-                if (exists[v]) {
+                if (hasNode(v)) {
                     handle(u, v);
                 }
             }
@@ -1568,9 +1568,9 @@ void Graph::parallelForNodePairs(L handle) const {
         // For mutable graphs, check exists
 #pragma omp parallel for schedule(guided)
         for (omp_index u = 0; u < static_cast<omp_index>(z); ++u) {
-            if (exists[u]) {
+            if (hasNode(u)) {
                 for (node v = u + 1; v < z; ++v) {
-                    if (exists[v]) {
+                    if (hasNode(v)) {
                         handle(u, v);
                     }
                 }
@@ -1678,7 +1678,7 @@ inline void Graph::forOutEdgesOfImpl(node u, L handle) const {
     } else {
         // Vector-based graphs should use GraphW
         // Check exists for mutable graphs
-        if (!exists[u])
+        if (!hasNode(u))
             return;
         throw std::runtime_error("forOutEdgesOfImpl not supported for vector-based graphs in base "
                                  "Graph class - use GraphW");
@@ -1732,12 +1732,12 @@ inline void Graph::forInEdgesOfImpl(node u, L handle) const {
     } else {
         // For vector-based graphs (GraphW), use the virtual dispatch
         // Check exists for mutable graphs
-        if (!exists[u])
+        if (!hasNode(u))
             return;
         // GraphW's forInEdgesVirtualImpl calls handle(v, u, ...) where v is neighbor and u is
         // current node We need to swap so that edgeLambda receives (current, neighbor, ...) and
         // passes neighbor to f
-        forInEdgesVirtualImpl(
+        forInEdgesOfVirtualImpl(
             u, graphIsDirected, hasWeights, graphHasEdgeIds,
             [&](node v, node u, edgeweight w, edgeid e) { edgeLambda(handle, u, v, w, e); });
     }
@@ -1936,6 +1936,10 @@ void Graph::forEdgesOf(node u, L handle) const {
             }
         }
     } else {
+        // For vector-based graphs (GraphW), use the virtual dispatch
+        // Check exists for mutable graphs
+        if (!hasNode(u))
+            return;
         // For vector-based graphs, use virtual dispatch
         forEdgesOfVirtualImpl(u, directed, weighted, edgesIndexed,
                               [&](node uu, node vv, edgeweight ww, edgeid ee) {

include/networkit/graph/GraphW.hpp

@@ -958,7 +958,7 @@ class GraphW final : public Graph {
     /**
      * @brief Override for vector-based forInEdgesOf
      */
-    void forInEdgesVirtualImpl(
+    void forInEdgesOfVirtualImpl(
         node u, bool directed, bool weighted, bool hasEdgeIds,
         std::function<void(node, node, edgeweight, edgeid)> handle) const override;
 
@@ -999,7 +999,7 @@ class GraphW final : public Graph {
     public:
         NeighborRange(const GraphW &G, node u) : G(&G), u(u) { assert(G.hasNode(u)); };
 
-        NeighborRange() : G(nullptr){};
+        NeighborRange() : G(nullptr) {};
 
         NeighborIterator begin() const {
             assert(G);
@@ -1037,7 +1037,7 @@ class GraphW final : public Graph {
     public:
         NeighborWeightRange(const GraphW &G, node u) : G(&G), u(u) { assert(G.hasNode(u)); };
 
-        NeighborWeightRange() : G(nullptr){};
+        NeighborWeightRange() : G(nullptr) {};
 
         NeighborWeightIterator begin() const {
             assert(G);