def countPaths(self):
pathCounts = {}
for sourceNode in self.graph:
for sinkNode in self.graph:
if sourceNode is not sinkNode:
# Calculate the paths between the nodes
paths = ksp_yen(self.graph,sourceNode,sinkNode,self.k)
for pathInfo in paths:
self._incrementLinksOnPath(pathInfo["path"], pathCounts)
return pathCounts
def countPaths(self):
for sourceNode in self.graph:
for sinkNode in self.graph:
if sinkNode >= sourceNode: # only traverse path in one direction
continue
paths = ksp_yen(self.graph,sourceNode,sinkNode,self.k)
if len(paths) == 0:
continue
# Increment path counts for KSP (always), ECMP (if cost = cost of shortest path)
minimumPathCost = paths[0]["cost"]
for pathInfo in paths:
self._incrementLinksOnPath(pathInfo["path"], self.kspPathCounts)
if pathInfo["cost"] == minimumPathCost:
# EC
self._incrementLinksOnPath(pathInfo["path"], self.ecmpPathCounts)
def _pairwise_shortest_routes(self, H):
# Find k shortest routes between all 2 nodes
k_shortests = []
for pair in itertools.product(range(0, self.n*self.m), repeat=2):
u,v = pair[0], pair[1]
if u == v:
continue
# dijkstra would be routes.append(nx.shortest_path(G,source=v,target=w))
k_shortest = algorithms.ksp_yen(H, u, v, max_k = self.r)
saved_routes = []
for shortest in k_shortest:
if GridNetwork.has_duplicate(shortest['path']):
k_shortest.remove(shortest)
shortest['o'], shortest['d'], shortest['flow'] = u, v, 0
saved_routes.append(shortest)
k_shortests.extend(saved_routes)
return k_shortests
def getRoutes(network,agents,k,cost=False):
emptyNetwork=deepcopy(network)
G=DiGraph()#graph class to create the object for YENs algorithm
for rowIdx, row in enumerate(emptyNetwork):
for colIdx, col in enumerate(row):
if col is not None:
col.seizeRequest()#add one car to each edge in the empty network
G.add_edge(rowIdx, colIdx, col.evalCost())#add an edge to the fixed network
#Get each agent's routes from Yen's algorithm and the fixed empty network
agentsRoutes=[None]*len(agents)
agentsRoutesCost=[None]*len(agents)
for agentIdx in range(len(agentsRoutes)):
agentsRoutes[agentIdx]=list()
agentsRoutesCost[agentIdx]=list()
for path in Yen.ksp_yen(G, agents[agentIdx].o, agents[agentIdx].d, k):
agentsRoutes[agentIdx].append(path['path'])
agentsRoutesCost[agentIdx].append(path['cost'])
costosZero=[[0 for i in range(len(agentsRoutesCost[j]))] for j in range(len(agentsRoutesCost))]
if cost:
return {'routes':agentsRoutes,'costs':costosZero}
else:
return(agentsRoutes)
