python - 将 NLTK Rake 应用于 Dataframe 中的每一行

Question

我想将 Rake 函数 ( https://pypi.org/project/rake-nltk/ ) 应用于数据框中的每一行。

我可以将函数单独应用于特定行，但不能将其附加到数据框。

这是我目前所拥有的:

r = Rake(ranking_metric= Metric.DEGREE_TO_FREQUENCY_RATIO, language= 'english', min_length=1, max_length=4)
r.extract_keywords_from_text(test.document[177])
r.get_ranked_phrases() #prints a list of keywords
test['keywords'] = test.applymap(lambda x: r.extract_keywords_from_text(x)) #trying to apply it to each row.

它只是无限期地运行。我只想在名为“关键字”的数据框“测试”中添加一个新列，其中包含来自 r.get_ranked_phrases() 的关键字列表。

Answer 1

r.extract_keywords_from_text(x) 将返回 None

import pandas as pd
from  rake_nltk import Rake  

r = Rake()    

df=pd.DataFrame(data = ['machine learning and fraud detection are a must learn',
                  'monte carlo method is great and so is hmm,pca, svm and neural net',
                  'clustering and cloud',
                  'logistical regression and data management and fraud detection'] ,columns = ['Comments'])


 def rake_implement(x,r):
     r.extract_keywords_from_text(x)
     return r.get_ranked_phrases()

df['new_col'] =df['Comments'].apply(lambda x: rake_implement(x,r))
print(df['new_col'])
#o/p
0      [must learn, machine learning, fraud detection]
1    [monte carlo method, neural net, svm, pca, hmm...
2                                  [clustering, cloud]
3    [logistical regression, fraud detection, data ...
Name: new_col, dtype: object