python - python中的numpy.str_错误预处理文本

Question

我正在尝试使用以下代码预处理 pandas 数据框中的列中的一些文本。预处理包括小写、标记和删除停用词。但是，我收到以下numpy.str_ object is not callable错误。知道我该如何解决这个问题吗？谢谢。

import nltk
import numpy as np
import re
from nltk.tokenize import RegexpTokenizer
from nltk.corpus import stopwords
import string

i = nltk.corpus.stopwords.words('english')
j = list(string.punctuation) 

stopwords = set(i).union(j)

def preprocess(x):
    x = re.sub('[^a-z\s]', '', x().lower())                  # get rid of noise
    x = [w for w in x.split() if w not in set(stopwords) if len(w) > 3]  # remove stopwords
    return ' '.join(x)   

preprocess2 = np.vectorize(preprocess)

merged_sort['processed_text'] = merged_sort['translated_text'].apply(preprocess2)

错误

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-22-e3eee761f15b> in <module>
----> 1 merged_sort['processed_text'] = merged_sort['translated_text'].apply(preprocess2)

~\Anaconda3\lib\site-packages\pandas\core\series.py in apply(self, func, convert_dtype, args, **kwds)
   3846             else:
   3847                 values = self.astype(object).values
-> 3848                 mapped = lib.map_infer(values, f, convert=convert_dtype)
   3849 
   3850         if len(mapped) and isinstance(mapped[0], Series):

pandas\_libs\lib.pyx in pandas._libs.lib.map_infer()

~\Anaconda3\lib\site-packages\numpy\lib\function_base.py in __call__(self, *args, **kwargs)
   2089             vargs.extend([kwargs[_n] for _n in names])
   2090 
-> 2091         return self._vectorize_call(func=func, args=vargs)
   2092 
   2093     def _get_ufunc_and_otypes(self, func, args):

~\Anaconda3\lib\site-packages\numpy\lib\function_base.py in _vectorize_call(self, func, args)
   2159             res = func()
   2160         else:
-> 2161             ufunc, otypes = self._get_ufunc_and_otypes(func=func, args=args)
   2162 
   2163             # Convert args to object arrays first

~\Anaconda3\lib\site-packages\numpy\lib\function_base.py in _get_ufunc_and_otypes(self, func, args)
   2119 
   2120             inputs = [arg.flat[0] for arg in args]
-> 2121             outputs = func(*inputs)
   2122 
   2123             # Performance note: profiling indicates that -- for simple

<ipython-input-21-1631cf3dded9> in preprocess(x)
     12 
     13 def preprocess(x):
---> 14     x = re.sub('[^a-z\s]', '', x().lower())                  # get rid of noise
     15     x = [w for w in x.split() if w not in set(stopwords) if len(w) > 3]  # remove stopwords
     16     return ' '.join(x)

TypeError: 'numpy.str_' object is not callable

标签： pythonpython-3.xpandasnltk