[教育工作者数据挖掘实训]利用 SMC 相似性计算文本之间的相似性

【Educoder数据挖掘实训】用SMC相似度计算文本之间的相似度

开挖！

还是计算文本之间相似度的实训，跟前两关区别不大。
需要注意的是$SMC$的计算方式$s=\frac{f11+f00}{f11+f00+f10+f01}$

代码如下：

import numpy as np  
import jieba  
jieba.setLogLevel(jieba.logging.INFO)  
  
def smc_similarity(sentence1: str, sentence2: str) -> float:  
    # 1. 实现文本分词  
    ########## Begin ##########
    seg1 = [word for word in jieba.cut(sentence1)]  
    seg2 = [word for word in jieba.cut(sentence2)]  
    ########## End ##########
    # 2. 建立词库  
    ########## Begin ##########
    word_list = list(set([word for word in seg1 + seg2]))  
    ########## End ##########
    # 3. 统计各个文本在词典里出现词的次数  
    ########## Begin ##########
    word_counts_1 = np.array([len([word for word in seg1 if word==w]) for w in word_list])  
    word_counts_2 = np.array([len([word for word in seg2 if word==w]) for w in word_list])  
    ########## End ##########
    # 4. 余弦公式  
    ########## Begin ##########
    f00 = np.sum((word_counts_1 == 0) & (word_counts_2 == 0))  
    f01 = np.sum((word_counts_1 == 0) & (word_counts_2 != 0))  
    f10 = np.sum((word_counts_1 != 0) & (word_counts_2 == 0))  
    f11 = np.sum((word_counts_1 != 0) & (word_counts_2 != 0))  
    smc = (f00 + f11) / (f01 + f10 + f00 + f11)  
    ########## End ##########
      
    return smc  
  
str1 = "我爱北京*"  
str2 = "*雄伟壮阔让人不得不爱"  
  
sim1 = smc_similarity(str1, str2)  
  
print(sim1)