Nodal efficiency measures

snap-exp/efficiency.cpp

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+#include "efficiency.hpp"
+#include <vector>
+
+namespace TSnap {
+
+    /////////////////////////////////////////////////
+    // Node efficiency measures
+    /////////////////////////////////////////////////
+    float getAvgEfficiency(const PUNGraph& Graph) {
+        float efficiency = 0.0;
+        float num = 1.0; 
+        float num_nodes = Graph->GetNodes(); 
+        vector<int> node_ids; 
+        for (typename PUNGraph::TObj::TNodeI NI = Graph->BegNI(); NI < Graph->EndNI(); NI++) {
+            node_ids.push_back(NI.GetId());
+        }
+        for (int i = 0; i < node_ids.size(); i++) {
+            for (int j = 0; j < node_ids.size(); j++) {
+                if (i != j) {
+                    efficiency += (num / (float) GetShortPath(Graph, i, j, true));
+                }
+            }
+        }
+        float ans = num / (num_nodes * (num_nodes-1)) * efficiency;
+        return ans; 
+    }
+
+    float getGlobalEfficiency(const PUNGraph& Graph) {
+        float E_G = getAvgEfficiency(Graph);
+        int num_nodes = Graph->GetNodes();
+        PUNGraph G_ideal = GenFull<PUNGraph>(num_nodes)
+        float E_G_ideal = getAvgEfficiency(G_ideal);
+        return E_G / E_G_ideal;
+    }
+
+
+}; // namespace TSnap

snap-exp/efficiency.h

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+namespace TSnap {
+
+	float getAvgEfficiency(const PUNGraph& Graph);
+	float getGlobalEfficiency(const PUNGraph& Graph);
+
+}