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Stanford CoreNLP API in NLTK

Dmitrijs Milajevs edited this page Mar 15, 2019 · 5 revisions

As of NLTK v3.3, users should avoid the Stanford NER or POS taggers from nltk.tag, and avoid Stanford tokenizer/segmenter from nltk.tokenize. They are currently deprecated and will be removed in due time.

Instead use the new nltk.parse.corenlp.CoreNLPParser API (Thanks to @dimazest and @artiemq!!)

pip3 install -U nltk # Make sure the version is  at least 3.3.

(It's usually a good practice to use the latest version of the software, especially when you are starting a new project.)

Then download the necessary CoreNLP packages:

cd ~
wget http://nlp.stanford.edu/software/stanford-corenlp-full-2018-02-27.zip
unzip stanford-corenlp-full-2018-02-27.zip
cd stanford-corenlp-full-2018-02-27

# Get the Chinese model 
wget http://nlp.stanford.edu/software/stanford-chinese-corenlp-2018-02-27-models.jar
wget https://raw.githubusercontent.com/stanfordnlp/CoreNLP/master/src/edu/stanford/nlp/pipeline/StanfordCoreNLP-chinese.properties 

# Get the Arabic model
wget http://nlp.stanford.edu/software/stanford-arabic-corenlp-2018-02-27-models.jar
wget https://raw.githubusercontent.com/stanfordnlp/CoreNLP/master/src/edu/stanford/nlp/pipeline/StanfordCoreNLP-arabic.properties 

# Get the French model
wget http://nlp.stanford.edu/software/stanford-french-corenlp-2018-02-27-models.jar
wget https://raw.githubusercontent.com/stanfordnlp/CoreNLP/master/src/edu/stanford/nlp/pipeline/StanfordCoreNLP-french.properties 

# Get the German model
wget http://nlp.stanford.edu/software/stanford-german-corenlp-2018-02-27-models.jar
wget https://raw.githubusercontent.com/stanfordnlp/CoreNLP/master/src/edu/stanford/nlp/pipeline/StanfordCoreNLP-german.properties 


# Get the Spanish model
wget http://nlp.stanford.edu/software/stanford-spanish-corenlp-2018-02-27-models.jar
wget https://raw.githubusercontent.com/stanfordnlp/CoreNLP/master/src/edu/stanford/nlp/pipeline/StanfordCoreNLP-spanish.properties 

English

Still in the stanford-corenlp-full-2018-02-27 directory, start the server:

java -mx4g -cp "*" edu.stanford.nlp.pipeline.StanfordCoreNLPServer \
-preload tokenize,ssplit,pos,lemma,ner,parse,depparse \
-status_port 9000 -port 9000 -timeout 15000 & 

Refer to the Stanford CorenNLP project documentation for the options, as you might need to adopt them to your specific needs. For example, when large pieces of text are processed you might need to increase the timeout option.

Then in Python:

>>> from nltk.parse import CoreNLPParser

# Lexical Parser
>>> parser = CoreNLPParser(url='http://localhost:9000')

# Parse tokenized text.
>>> list(parser.parse('What is the airspeed of an unladen swallow ?'.split()))
[Tree('ROOT', [Tree('SBARQ', [Tree('WHNP', [Tree('WP', ['What'])]), Tree('SQ', [Tree('VBZ', ['is']), Tree('NP', [Tree('NP', [Tree('DT', ['the']), Tree('NN', ['airspeed'])]), Tree('PP', [Tree('IN', ['of']), Tree('NP', [Tree('DT', ['an']), Tree('JJ', ['unladen'])])]), Tree('S', [Tree('VP', [Tree('VB', ['swallow'])])])])]), Tree('.', ['?'])])])]

# Parse raw string.
>>> list(parser.raw_parse('What is the airspeed of an unladen swallow ?'))
[Tree('ROOT', [Tree('SBARQ', [Tree('WHNP', [Tree('WP', ['What'])]), Tree('SQ', [Tree('VBZ', ['is']), Tree('NP', [Tree('NP', [Tree('DT', ['the']), Tree('NN', ['airspeed'])]), Tree('PP', [Tree('IN', ['of']), Tree('NP', [Tree('DT', ['an']), Tree('JJ', ['unladen'])])]), Tree('S', [Tree('VP', [Tree('VB', ['swallow'])])])])]), Tree('.', ['?'])])])]

# Neural Dependency Parser
>>> from nltk.parse.corenlp import CoreNLPDependencyParser
>>> dep_parser = CoreNLPDependencyParser(url='http://localhost:9000')
>>> parses = dep_parser.parse('What is the airspeed of an unladen swallow ?'.split())
>>> [[(governor, dep, dependent) for governor, dep, dependent in parse.triples()] for parse in parses]
[[(('What', 'WP'), 'cop', ('is', 'VBZ')), (('What', 'WP'), 'nsubj', ('airspeed', 'NN')), (('airspeed', 'NN'), 'det', ('the', 'DT')), (('airspeed', 'NN'), 'nmod', ('swallow', 'VB')), (('swallow', 'VB'), 'case', ('of', 'IN')), (('swallow', 'VB'), 'det', ('an', 'DT')), (('swallow', 'VB'), 'amod', ('unladen', 'JJ')), (('What', 'WP'), 'punct', ('?', '.'))]]


# Tokenizer
>>> parser = CoreNLPParser(url='http://localhost:9000')
>>> list(parser.tokenize('What is the airspeed of an unladen swallow?'))
['What', 'is', 'the', 'airspeed', 'of', 'an', 'unladen', 'swallow', '?']

# POS Tagger
>>> pos_tagger = CoreNLPParser(url='http://localhost:9000', tagtype='pos')
>>> list(pos_tagger.tag('What is the airspeed of an unladen swallow ?'.split()))
[('What', 'WP'), ('is', 'VBZ'), ('the', 'DT'), ('airspeed', 'NN'), ('of', 'IN'), ('an', 'DT'), ('unladen', 'JJ'), ('swallow', 'VB'), ('?', '.')]

# NER Tagger
>>> ner_tagger = CoreNLPParser(url='http://localhost:9000', tagtype='ner')
>>> list(ner_tagger.tag(('Rami Eid is studying at Stony Brook University in NY'.split())))
[('Rami', 'PERSON'), ('Eid', 'PERSON'), ('is', 'O'), ('studying', 'O'), ('at', 'O'), ('Stony', 'ORGANIZATION'), ('Brook', 'ORGANIZATION'), ('University', 'ORGANIZATION'), ('in', 'O'), ('NY', 'STATE_OR_PROVINCE')]

Chinese

Start the server a little differently, still from the `stanford-corenlp-full-2018-02-27 directory:

java -Xmx4g -cp "*" edu.stanford.nlp.pipeline.StanfordCoreNLPServer \
-serverProperties StanfordCoreNLP-chinese.properties \
-preload tokenize,ssplit,pos,lemma,ner,parse \
-status_port 9001  -port 9001 -timeout 15000

In Python:

>>> parser = CoreNLPParser('http://localhost:9001')
>>> list(parser.tokenize(u'我家没有电脑。'))
['我家', '没有', '电脑', '。']

>>> list(parser.parse(parser.tokenize(u'我家没有电脑。')))
[Tree('ROOT', [Tree('IP', [Tree('IP', [Tree('NP', [Tree('NN', ['我家'])]), Tree('VP', [Tree('VE', ['没有']), Tree('NP', [Tree('NN', ['电脑'])])])]), Tree('PU', ['。'])])])]

Arabic

Start the server:

java -Xmx4g -cp "*" edu.stanford.nlp.pipeline.StanfordCoreNLPServer \
-serverProperties StanfordCoreNLP-arabic.properties \
-preload tokenize,ssplit,pos,parse \
-status_port 9005  -port 9005 -timeout 15000

In Python:

>>> from nltk.parse import CoreNLPParser
>>> parser = CoreNLPParser('http://localhost:9005')
>>> text = u'انا حامل'

# Parser.
>>> parser.raw_parse(text)
<list_iterator object at 0x7f0d894c9940>
>>> list(parser.raw_parse(text))
[Tree('ROOT', [Tree('S', [Tree('NP', [Tree('PRP', ['انا'])]), Tree('NP', [Tree('NN', ['حامل'])])])])]
>>> list(parser.parse(parser.tokenize(text)))
[Tree('ROOT', [Tree('S', [Tree('NP', [Tree('PRP', ['انا'])]), Tree('NP', [Tree('NN', ['حامل'])])])])]

# Tokenizer / Segmenter.
>>> list(parser.tokenize(text))
['انا', 'حامل']

# POS tagg
>>> pos_tagger = CoreNLPParser('http://localhost:9005', tagtype='pos')
>>> list(pos_tagger.tag(parser.tokenize(text)))
[('انا', 'PRP'), ('حامل', 'NN')]


# NER tag
>>> ner_tagger = CoreNLPParser('http://localhost:9005', tagtype='ner')
>>> list(ner_tagger.tag(parser.tokenize(text)))
[('انا', 'O'), ('حامل', 'O')]

French

Start the server:

java -Xmx4g -cp "*" edu.stanford.nlp.pipeline.StanfordCoreNLPServer \
-serverProperties StanfordCoreNLP-french.properties \
-preload tokenize,ssplit,pos,parse \
-status_port 9004  -port 9004 -timeout 15000

In Python:

>>> parser = CoreNLPParser('http://localhost:9004')
>>> list(parser.parse('Je suis enceinte'.split()))
[Tree('ROOT', [Tree('SENT', [Tree('NP', [Tree('PRON', ['Je']), Tree('VERB', ['suis']), Tree('AP', [Tree('ADJ', ['enceinte'])])])])])]
>>> pos_tagger = CoreNLPParser('http://localhost:9004', tagtype='pos')
>>> pos_tagger.tag('Je suis enceinte'.split())
[('Je', 'PRON'), ('suis', 'VERB'), ('enceinte', 'ADJ')]

German

Start the server:

java -Xmx4g -cp "*" edu.stanford.nlp.pipeline.StanfordCoreNLPServer \
-serverProperties StanfordCoreNLP-german.properties \
-preload tokenize,ssplit,pos,ner,parse \
-status_port 9002  -port 9002 -timeout 15000

In Python:

>>> parser = CoreNLPParser('http://localhost:9002')
>>> list(parser.raw_parse('Ich bin schwanger'))
[Tree('ROOT', [Tree('NUR', [Tree('S', [Tree('PPER', ['Ich']), Tree('VAFIN', ['bin']), Tree('AP', [Tree('ADJD', ['schwanger'])])])])])]
>>> list(parser.parse('Ich bin schwanger'.split()))
[Tree('ROOT', [Tree('NUR', [Tree('S', [Tree('PPER', ['Ich']), Tree('VAFIN', ['bin']), Tree('AP', [Tree('ADJD', ['schwanger'])])])])])]


>>> pos_tagger = CoreNLPParser('http://localhost:9002', tagtype='pos')
>>> pos_tagger.tag('Ich bin schwanger'.split())
[('Ich', 'PPER'), ('bin', 'VAFIN'), ('schwanger', 'ADJD')]

>>> pos_tagger = CoreNLPParser('http://localhost:9002', tagtype='pos')
>>> pos_tagger.tag('Ich bin schwanger'.split())
[('Ich', 'PPER'), ('bin', 'VAFIN'), ('schwanger', 'ADJD')]

>>> ner_tagger = CoreNLPParser('http://localhost:9002', tagtype='ner')
>>> ner_tagger.tag('Donald Trump besuchte Angela Merkel in Berlin.'.split())
[('Donald', 'PERSON'), ('Trump', 'PERSON'), ('besuchte', 'O'), ('Angela', 'PERSON'), ('Merkel', 'PERSON'), ('in', 'O'), ('Berlin', 'LOCATION'), ('.', 'O')]

Spanish

Start the server:

java -Xmx4g -cp "*" edu.stanford.nlp.pipeline.StanfordCoreNLPServer \
-serverProperties StanfordCoreNLP-spanish.properties \
-preload tokenize,ssplit,pos,ner,parse \
-status_port 9003  -port 9003 -timeout 15000

In Python:

>>> pos_tagger = CoreNLPParser('http://localhost:9003', tagtype='pos')
>>> pos_tagger.tag(u'Barack Obama salió con Michael Jackson .'.split())
[('Barack', 'PROPN'), ('Obama', 'PROPN'), ('salió', 'VERB'), ('con', 'ADP'), ('Michael', 'PROPN'), ('Jackson', 'PROPN'), ('.', 'PUNCT')]
>>> ner_tagger = CoreNLPParser('http://localhost:9003', tagtype='ner')
>>> ner_tagger.tag(u'Barack Obama salió con Michael Jackson .'.split())
[('Barack', 'PERSON'), ('Obama', 'PERSON'), ('salió', 'O'), ('con', 'O'), ('Michael', 'PERSON'), ('Jackson', 'PERSON'), ('.', 'O')]

What's Next?

If you're up for a challenge, there are other tools not wrapped in the nltk.parse.corenlp:

You can use the CoreNLPParser.api_call() to get the json output and then wrap the output parser to wrap it into NLTK suitable objects. =)

Looking forward to your contributions!