python – Maltparser在NLTK中给出错误

我的COde是

from nltk.parse import malt
mp = malt.MaltParser(working_dir="/other/apps/maltparser-1.8.1",mco="engmalt.poly-1.7.mco",additional_java_args=['-Xmx1024m'])
print mp.raw_parse("Hello World")

错误是

    Traceback (most recent call last):
  File "malt.py", line 13, in <module>
    print mp.raw_parse("Hello World")
  File "/usr/local/lib/python2.7/dist-packages/nltk/parse/malt.py", line 139, in raw_parse
    return self.parse(words, verbose)
  File "/usr/local/lib/python2.7/dist-packages/nltk/parse/malt.py", line 126, in parse
    return self.parse_sents([sentence], verbose)[0]
  File "/usr/local/lib/python2.7/dist-packages/nltk/parse/malt.py", line 114, in parse_sents
    return self.tagged_parse_sents(tagged_sentences, verbose)
  File "/usr/local/lib/python2.7/dist-packages/nltk/parse/malt.py", line 194, in tagged_parse_sents
    "code %d" % (' '.join(cmd), ret))
Exception: MaltParser parsing (java -Xmx1024m -jar /usr/local/bin/malt.jar -w /other/apps/maltparser-1.8.1 -c engmalt.poly-1.7.mco -i /other/apps/maltparser-1.8.1/malt_input.conlljOba1P -o /other/apps/maltparser-1.8.1/malt_output.conllPLcoTu -m parse) Failed with exit code 1

解决方法:

NLTK中的MaltParser API只有a patch修复并稳定了以前的问题：

> How to use malt parser in python nltk
> Malt Parser throwing class not found exception
> MaltParser Not Working in Python NLTK

以下是如何在NLTK中使用MaltParser API的示例：

# Upgrade your NLTK.
alvas@ubi:~$cd ~
alvas@ubi:~$pip install -U nltk

# Get the latest MaltParser and model
alvas@ubi:~$wget http://maltparser.org/dist/maltparser-1.8.1.zip
alvas@ubi:~$unzip maltparser-1.8.1.zip 
alvas@ubi:~$wget http://www.maltparser.org/mco/english_parser/engmalt.poly-1.7.mco

# In python, Now you can do this:
alvas@ubi:~$python
>>> from nltk.parse.malt import MaltParser
>>> mp = MaltParser('/home/alvas/maltparser-1.8.1', '/home/alvas/engmalt.poly-1.7.mco')
>>> sent1 = 'I shot an elephant in my pajamas .'.split()
>>> print(mp.parse_one(sent1).tree())
(shot I (elephant an (in (pajamas my))) .)

(有关更多演示代码,请参阅here;有关更详细的演示代码,请参阅here)

请注意,您还可以使用导出功能,并且可以在初始化MaltParser对象时转义完整路径的使用.但是你必须告诉对象要查找的解析器目录和模型文件名的名称是什么,例如

alvas@ubi:~$export MALT_PARSER='/home/$UID/maltparser-1.8.1/'
alvas@ubi:~$export MALT_MODEL='/home/$UID/engmalt.poly-1.7.mco' 
alvas@ubi:~$python
>>> from nltk.parse.malt import MaltParser
>>> mp = MaltParser('maltparser-1.8.1', 'engmalt.poly-1.7.mco')
>>> sent1 = 'I shot an elephant in my pajamas .'.split()
>>> print(mp.parse_one(sent1).tree())
(shot I (elephant an (in (pajamas my))) .)