帮我写一个textRANK算法代码
时间: 2023-05-11 10:01:42 浏览: 105
好的,以下是一个简单的textRANK算法的Python代码:
```
import jieba
import numpy as np
class TextRank:
def __init__(self, text, window=5, alpha=0.85, eps=1e-4):
self.text = text
self.window = window
self.alpha = alpha
self.eps = eps
self.words = list(jieba.cut(text))
self.word_set = list(set(self.words))
self.word_index = {w: i for i, w in enumerate(self.word_set)}
self.word_count = len(self.word_set)
self.graph = np.zeros((self.word_count, self.word_count))
self.weights = np.zeros(self.word_count)
self.scores = np.ones(self.word_count)
def build_graph(self):
for i in range(len(self.words)):
for j in range(i - self.window, i + self.window + 1):
if j < 0 or j >= len(self.words) or i == j:
continue
self.graph[self.word_index[self.words[i]]][self.word_index[self.words[j]]] += 1
def calculate_weights(self):
for i in range(self.word_count):
self.weights[i] = np.sum(self.graph[i])
def update_scores(self):
new_scores = np.zeros(self.word_count)
for i in range(self.word_count):
for j in range(self.word_count):
if self.graph[j][i] != 0:
new_scores[i] += self.alpha * self.scores[j] / self.weights[j]
new_scores[i] += 1 - self.alpha
if np.sum(np.abs(new_scores - self.scores)) < self.eps:
return False
self.scores = new_scores
return True
def get_top_keywords(self, k=10):
for i in range(100):
if not self.update_scores():
break
top_indices = np.argsort(-self.scores)[:k]
return [self.word_set[i] for i in top_indices]
text = "这是一段测试文本,用于测试textRank算法的效果。"
tr = TextRank(text)
tr.build_graph()
tr.calculate_weights()
keywords = tr.get_top_keywords()
print(keywords)
```
这个算法可以用于提取文本中的关键词,它基于图论的思想,将文本中的词语看作图中的节点,词语之间的共现关系看作边,通过迭代计算每个节点的权重,最终得到文本中的关键词。
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