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nltk tags

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The module NLTK can automatically tag speech.
Given a sentence or paragraph, it can label words such as verbs, nouns and so on.

NLTK - speech tagging example

The example below automatically tags words with a corresponding class.

import nltk
from nltk.tokenize import PunktSentenceTokenizer

document = 'Whether you\'re new to programming or an experienced developer, it\'s easy to learn and use Python.'
sentences = nltk.sent_tokenize(document)
for sent in sentences:

Related course
Easy Natural Language Processing (NLP) in Python

This will output a tuple for each word:
where the second element of the tuple is the class.
The meanings of these speech codes are shown in the table below:

We can filter this data based on the type of word:

import nltk
from nltk.corpus import state_union
from nltk.tokenize import PunktSentenceTokenizer

document = 'Today the Netherlands celebrates King\'s Day. To honor this tradition, the Dutch embassy in San Francisco invited me to'
sentences = nltk.sent_tokenize(document)

data = []
for sent in sentences:
data = data + nltk.pos_tag(nltk.word_tokenize(sent))

for word in data:
if 'NNP' in word[1]:

which outputs:

speech tagging Speech tagging

The classes include past tense, present. Using this technique we can quickly derive meaning from a text.


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