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我首先将 pdf 转换为纯文本（我将其打印出来，一切都很好），然后当我尝试从 NLTK 运行 word_tokenize() 时出现 UnicodeDecodeError。

尽管我事先尝试在纯文本上 decode('utf-8').encode('utf-8') ，但我还是收到了这个错误。在回溯中，我注意到 word_tokenize() 中首先引发错误的代码行是 plaintext.split('\n')。这就是为什么我试图通过在纯文本上运行 split('\n') 来重现该错误，但仍然不会产生任何错误。

所以，我既不了解导致错误的原因，也不了解如何避免它。

任何帮助将不胜感激！:) 也许我可以通过更改 pdf_to_txt 文件中的某些内容来避免它？

这是标记化的代码：

from cStringIO import StringIO
from nltk.corpus import stopwords
from nltk.tokenize import word_tokenize
import os
import string
from pdfminer.pdfinterp import PDFResourceManager, PDFPageInterpreter
from pdfminer.converter import TextConverter
from pdfminer.layout import LAParams
from pdfminer.pdfpage import PDFPage

stopset = stopwords.words('english')
path = 'my_folder'
listing = os.listdir(path)
for infile in listing:
        text = self.convert_pdf_to_txt(path+infile)
        text = text.decode('utf-8').encode('utf-8').lower()
        print text
        splitted = text.split('\n')
        filtered_tokens = [i for i in word_tokenize(text) if i not in stopset and i not in string.punctuation]

这是我为了从pdf转换为txt而调用的方法：

def convert_pdf_to_txt(self, path):
    rsrcmgr = PDFResourceManager()
    retstr = StringIO()
    codec = 'utf-8'
    laparams = LAParams()
    device = TextConverter(rsrcmgr, retstr, codec=codec, laparams=laparams)
    fp = file(path, 'rb')
    interpreter = PDFPageInterpreter(rsrcmgr, device)
    password = ""
    maxpages = 0
    caching = True
    pagenos=set()
    for page in PDFPage.get_pages(fp, pagenos, maxpages=maxpages, password=password,caching=caching, check_extractable=True):
        interpreter.process_page(page)
    fp.close()
    device.close()
    ret = retstr.getvalue()
    retstr.close()
    return ret

这是我得到的错误的回溯：

    Traceback (most recent call last):
  File "/home/iammyr/opt/workspace/task-logger/task_logger/nlp/pre_processing.py", line 65, in <module>
    obj.tokenizeStopWords()
  File "/home/iammyr/opt/workspace/task-logger/task_logger/nlp/pre_processing.py", line 29, in tokenizeStopWords
    filtered_tokens = [i for i in word_tokenize(text) if i not in stopset and i not in string.punctuation]
  File "/usr/local/lib/python2.7/dist-packages/nltk/tokenize/__init__.py", line 93, in word_tokenize
    return [token for sent in sent_tokenize(text)
  [...]
  File "/usr/local/lib/python2.7/dist-packages/nltk/tokenize/punkt.py", line 586, in _tokenize_words
    for line in plaintext.split('\n'):
UnicodeDecodeError: 'ascii' codec can't decode byte 0xc2 in position 9: ordinal not in range(128)

感谢一百万和大量的好业力给你！;)

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1 回答 1

4

您正在将一段非常好的 Unicode 字符串（返回）变成一堆无类型的字节，Python 不知道如何处理，但拼命地尝试应用 ASCII 编解码器。删除.encode('utf-8')，你应该没问题。

另见http://nedbatchelder.com/text/unipain.html

于 2014-08-15T09:10:22.820 回答