premature optimization

evrouting/gasstation/routing.py

@@ -101,10 +101,12 @@ def contract_graph(G: nx.Graph, charging_stations: Set[Node], capacity: SoC,
     """
     H: nx.Graph = nx.Graph()
 
-    for cs in list(charging_stations):
+    all_cs = list(charging_stations)
+    for i in range(len(all_cs) - 1):
+        cs = all_cs[i]
         H.add_node(cs, **G.nodes[cs])
         # Iterate unvisited charging stations
-        for n_cs in [n for n in charging_stations if (n, cs) not in H.edges and n != cs]:
+        for n_cs in all_cs[i + 1:]:
             min_path: List[Node] = dist(G, cs, n_cs)
             w_cs_n: SoC = fold_path(G, min_path, weight=CONSUMPTION_KEY)
             if w_cs_n <= capacity:
@@ -115,6 +117,8 @@ def contract_graph(G: nx.Graph, charging_stations: Set[Node], capacity: SoC,
                         DISTANCE_KEY: fold_path(G, min_path, weight=DISTANCE_KEY)
                     }
                 )
+    H.add_node(all_cs[-1], **G.nodes[all_cs[-1]])
+
     return H