Python 类型错误：必须是 unicode，而不是 NLTK 中的 str
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TypeError: must be unicode, not str in NLTK
提问by backtrack
I am using python2.7, nltk 3.2.1 and python-crfsuite 0.8.4. I am following this page : http://www.nltk.org/api/nltk.tag.html?highlight=stanford#nltk.tag.stanford.NERTaggerfor nltk.tag.crf module.
我正在使用 python2.7、nltk 3.2.1 和 python-crfsuite 0.8.4。我正在关注此页面：http: //www.nltk.org/api/nltk.tag.html?highlight =stanford#nltk.tag.stanford.NERTagger 用于 nltk.tag.crf 模块。
To start with i just run this
首先我只是运行这个
from nltk.tag import CRFTagger
ct = CRFTagger()
train_data = [[('dfd','dfd')]]
ct.train(train_data,"abc")
I tried this too
我也试过这个
f = open("abc","wb")
ct.train(train_data,f)
but i am getting the following error,
但我收到以下错误，
File "C:\Python27\lib\site-packages\nltk\tag\crf.py", line 129, in <genexpr>
if all (unicodedata.category(x) in punc_cat for x in token):
TypeError: must be unicode, not str
回答by tripleee
In Python 2, regular quotes '...'or "..."create byte strings. To get Unicode strings, use a uprefix before the string, like u'dfd'.
在 Python 2 中，常规引号'...'或"..."创建字节字符串。要获取 Unicode 字符串，请u在字符串前使用前缀，例如u'dfd'.
To read from a file, you'll want to specify an encoding. See Backporting Python 3 open(encoding="utf-8")to Python 2for options; most straightforwardly, replace open()with io.open().
要从文件中读取，您需要指定编码。有关选项，请参阅将Python 3 向后移植open(encoding="utf-8")到 Python 2；最直接地，替换open()为io.open().
To convert an existing string, use the unicode()method; though usually, you'll want to use decode()and supply an encoding, too.
要转换现有字符串，请使用该unicode()方法；虽然通常情况下，您也需要使用decode()和提供编码。
For (much) more details, Ned Batchelder's "Pragmatic Unicode" slides are recommended, if not outright obligatory reading; http://nedbatchelder.com/text/unipain.html
对于（更多）更多细节，推荐 Ned Batchelder 的“Pragmatic Unicode”幻灯片，如果不是完全必须阅读的话；http://nedbatchelder.com/text/unipain.html
