如何使用python字典保存图形边缘权重

Question

i want to save graph edge weight my input is something like this

[['A', 'B', '5']]

it means we have edge from 'A' to 'B' with weight 5

and my code is

def inputFormatter(array):

    Nodes={}

    for p in array:

        a=p[0]
        b=p[1]
        value=p[2]

        if(a not in Nodes):
            Nodes[a]=NodeInfo(a)

        if(b not in Nodes[a].neighbors):
            Nodes[a].neighbors[b]=value


        if(b not in Nodes):
            Nodes[b]=NodeInfo(b)

        if(a not in Nodes[b].neighbors):
            Nodes[b].neighbors[a]=value

    return Nodes

my NodeInfo Class is

class NodeInfo:

    neighbors={}
    nodeName=""

    def __init__(self, nodeName):
        self.nodeName=nodeName

but in printing neighbors key with this code

for node in Nodes:
    print node.nodeName +"\t"+ str(node.neighbors.keys())

i see this

A   ['A', 'B']
B   ['A', 'B']

why? what's wrong? How Can i Fix this?

Answer 1

Your neighbors are a class variable so they are shared in between instances. You should try:

class NodeInfo:
    def init(self, nodeName):
        self.nodeName = nodeName
        self.neighbors = {}

Note that you're overriding the class member nodeName with an instance member when you do self.nodeName = nodeName (which is why you don't see that they share it).