Fix handling of parallel edges

This commit fixes an issue where we were overcounting parallel edges in the graph. There was a bug in the logic that was calculating the combined weight of parallel edges incorrectly. Co-authored-by: georgios-ts <[email protected]>
Qiskit · Jun 9, 2022 · e03856b · e03856b
1 parent 97fcc61
commit e03856b
Showing 1 changed file with 3 additions and 9 deletions.
diff --git a/retworkx-core/src/centrality.rs b/retworkx-core/src/centrality.rs
@@ -363,15 +363,9 @@ where
         let x_last = x.clone();
         for node_index in graph.node_identifiers() {
             let node = graph.to_index(node_index);
-            for neighbor in graph.neighbors(node_index) {
-                let w_vec: Vec<G::EdgeRef> = graph
-                    .edges(node_index)
-                    .filter(|edge| edge.target() == neighbor)
-                    .collect();
-                let mut w = 0.;
-                for edge in w_vec {
-                    w += weight_fn(edge)?;
-                }
+            for edge in graph.edges(node_index) {
+                let w = weight_fn(edge)?;
+                let neighbor = edge.target();
                 x[graph.to_index(neighbor)] += x_last[node] * w;
             }
         }