'''

@author: Administrator
'''

def inNodes(node,edges):
    ins=[]
    for edge in edges:
        if edge[1]==node:
            ins.append(edge[0])
    return ins

def update_simRank(node1,node2,edges,simRank):
    if node1==node2:
        simRank[(node1,node2)]=1
        simRank[(node2,node1)]=1
        return simRank
    ins_1=inNodes(node1,edges)
    ins_2=inNodes(node2,edges)
    if len(ins_1)==0 or len(ins_2)==0:
        simRank[(node1,node2)]=0
        simRank[(node2,node1)]=0
        return simRank
    sum_sim=0
    for i in ins_1:
        for j in ins_2:
            if (i,j) in simRank:
                sum_sim+=simRank[(i,j)]
            elif i==j:
                sum_sim+=1
            else:
                sum_sim+=0
    C=0.8
    sim_ab=C*sum_sim/(len(ins_1)*len(ins_2))
    simRank[(node1,node2)]=sim_ab
    simRank[(node2,node1)]=sim_ab
    return simRank

if __name__ == '__main__':
    nodes=["Univ","ProfA","StudentA","ProfB","StudentB"]
    edges=[];
    edges.append(["Univ","ProfA"])
    edges.append(["Univ","ProfB"])
    edges.append(["ProfA","StudentA"])
    edges.append(["StudentA","Univ"])
    edges.append(["ProfB","StudentB"])
    edges.append(["StudentB","ProfB"])
    simRank={}
    i_total=20
    for i in range(i_total):
        for node1 in range(len(nodes)):
            for node2 in range(node1,len(nodes)):
                simRank=update_simRank(nodes[node1],nodes[node2],edges,simRank)
        print(simRank)

结果是：

{('Univ', 'Univ'): 1, ('Univ', 'ProfA'): 0.0, ('ProfA', 'Univ'): 0.0, ('Univ', 'StudentA'): 0.0, ('StudentA', 'Univ'): 0.0, ('Univ', 'ProfB'): 0.0, ('ProfB', 'Univ'): 0.0, ('Univ', 'StudentB'): 0.0, ('StudentB', 'Univ'): 0.0, ('ProfA', 'ProfA'): 1, ('ProfA', 'StudentA'): 0.0, ('StudentA', 'ProfA'): 0.0, ('ProfA', 'ProfB'): 0.4, ('ProfB', 'ProfA'): 0.4, ('ProfA', 'StudentB'): 0.0, ('StudentB', 'ProfA'): 0.0, ('StudentA', 'StudentA'): 1, ('StudentA', 'ProfB'): 0.0, ('ProfB', 'StudentA'): 0.0, ('StudentA', 'StudentB'): 0.32000000000000006, ('StudentB', 'StudentA'): 0.32000000000000006, ('ProfB', 'ProfB'): 1, ('ProfB', 'StudentB'): 0.0, ('StudentB', 'ProfB'): 0.0, ('StudentB', 'StudentB'): 1}