same community has infinite cbc

pydyton/communities/base.py

@@ -34,7 +34,7 @@ class EpochCommunity(TickProcess):
             edge['start'] = -1
 
     def next_epoch(self, now):
-        self.community = defaultdict(frozenset)
+        self.community = {}
         edges_to_keep = []
         self.cache_clear()
 
@@ -103,7 +103,7 @@ class EpochCommunity(TickProcess):
     def get_cbc(self, c_x, c_y):
         ''''''
         if c_x == c_y:
-            return 0
+            return float('inf')
         g = self.old_graph
         return sum([
             g[x][y]['duration']