def preproc_graph(filename):
''' get connected graph
I beleive this is done after we remap the nodes to
consecutive order in map_nodes_new.py
'''
print "Working on %s \n" % filename
print "Generating graph from edge list..."
# laod edge list into snap
Graph0 = snap.LoadEdgeList(snap.PUNGraph, filename, 0, 1, '\t')
# get edges
V0 = Graph0.GetNodes()
# delete zero degree nodes
snap.DelZeroDegNodes(Graph0)
print "Done generating graph!"
# get max weakly connected component
print "Generating connected graph..."
Graph = snap.GetMxWcc(Graph0)
V = Graph.GetNodes()
E = Graph.GetEdges()
print "Done generating graph with V = %i, E = %i!, V0 = %i" % (V, E, V0)
# get nodes included in weakly connected graph (which could be
# a proper subset of original set)
# Find one edge in graph and find all connected nodes
for EI in Graph.Edges():
conn_node = EI.GetSrcNId() # start with one edge
break # only need one edge since connected
CnCom = snap.TIntV()
snap.GetNodeWcc(Graph, conn_node, CnCom)
conn_node_ids = sort(array([node for node in CnCom]))
return Graph, conn_node_ids, V, E, V0
def calcCnctComponents(graph):
lenComps = {}
CnCom = snap.TIntV()
for node in graph.Nodes():
nodeid = node.GetId()
if nodeid in lenComps:
continue
snap.GetNodeWcc(graph, nodeid, CnCom)
l = CnCom.Len()
lenComps[nodeid] = l
for conNode in CnCom:
lenComps[conNode] = l
return lenComps
def labelConnectedComponents(graph):
components = {}
CnCom = snap.TIntV()
component = 1
for node in graph.Nodes():
nodeid = node.GetId()
if nodeid in components:
continue
snap.GetNodeWcc(graph, nodeid, CnCom)
if len(CnCom) == 1:
components[nodeid] = 0.0
else:
for cnid in CnCom:
components[cnid] = component
component += 1
return components
# test if the graph is connected or weakly connected
print("IsConnected(G) =", snap.IsConnected(G))
print("IsWeaklyConnected(G) =", snap.IsWeaklyConn(G))
# get the weakly connected component counts
WccSzCnt = snap.TIntPr64V()
snap.GetWccSzCnt(G, WccSzCnt)
#print (WccSzCnt[0],WccSzCnt[0].Val1,WccSzCnt[0].Val2)
for i in range(0, WccSzCnt.Len()):
print("WccSzCnt[%d] = (%d, %d)" %
(i, WccSzCnt[i].Val1.Val, WccSzCnt[i].Val2.Val))
# return nodes in the same weakly connected component as node 1
CnCom = snap.TInt64V()
snap.GetNodeWcc(G, 1, CnCom)
print("CnCom.Len() = %d" % (CnCom.Len()))
# get nodes in weakly connected components
WCnComV = snap.TCnComV()
snap.GetWccs(G, WCnComV)
for i in range(0, WCnComV.Len()):
print("WCnComV[%d].Len() = %d" % (i, WCnComV[i].Len()))
for j in range(0, WCnComV[i].Len()):
print("WCnComV[%d][%d] = %d" % (i, j, WCnComV[i][j]))
# get the size of the maximum weakly connected component
MxWccSz = snap.GetMxWccSz(G)
print("MxWccSz = %.5f" % (MxWccSz))
# get the graph with the largest weakly connected component
def get_size_of_conn_comp(G, n):
CnCom = snap.TIntV()
return len(snap.GetNodeWcc(G, n, CnCom))
import snap
Graph = snap.GenRndGnm(snap.PNGraph, 100, 1000)
CnCom = snap.TInt64V()
snap.GetNodeWcc(Graph, 0, CnCom)
print("Nodes in the same connected component as node 0:")
for node in CnCom:
print(node)
def nodesInWcc(self, returnNodes=True):
nodes = snap.TIntV()
snap.GetNodeWcc(self.parentGraph.rawGraph, self.id, nodes)
return SnapUtil.rawComponentToNodeSet(nodes, self.parentGraph, returnNodes)
