python中用PageRank算法计算acl.txt文本节点的PR值的代码
时间: 2024-05-08 13:19:43 浏览: 183
以下是Python中用PageRank算法计算acl.txt文本节点的PR值的示例代码:
```
import numpy as np
# 读取acl.txt文本文件并创建图结构
with open('acl.txt') as file:
lines = file.readlines()
graph = {}
nodes = set()
for line in lines:
node, neighbor = line.strip().split(' ')
nodes.add(node)
nodes.add(neighbor)
if node not in graph:
graph[node] = []
graph[node].append(neighbor)
# 初始化PageRank值和转移矩阵
n = len(nodes)
pagerank = np.ones(n) / n
transition_matrix = np.zeros((n, n))
# 构建转移矩阵
for i, node in enumerate(sorted(nodes)):
if node in graph:
neighbors = graph[node]
for neighbor in neighbors:
j = sorted(nodes).index(neighbor)
transition_matrix[j, i] = 1 / len(neighbors)
# 迭代计算PageRank值
d = 0.85 # damping factor
for _ in range(100):
pagerank_new = (1 - d) / n + d * transition_matrix.dot(pagerank)
if abs(pagerank_new - pagerank).max() < 1e-6:
break
pagerank = pagerank_new
# 输出节点PR值
for i, node in enumerate(sorted(nodes)):
print('{}: {:.4f}'.format(node, pagerank[i]))
```
这段代码使用Python的numpy模块计算PageRank值,并将结果输出到终端。为了保证隐私安全,代码中没有保存或打印任何用户信息。
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