Python Text Processing - Corpora Access

Corpora is a group presenting multiple collections of text documents. A single collection is called corpus. One such famous corpus is the Gutenberg Corpus which contains some 25,000 free electronic books, hosted at http://www.gutenberg.org/. In the below example we access the names of only those files from the corpus which are plain text with filename ending as .txt.

main.py

from nltk.corpus import gutenberg
fields = gutenberg.fileids()

print(fields)

Output

When we run the above program, we get the following output −

[austen-emma.txt', austen-persuasion.txt', austen-sense.txt', bible-kjv.txt', 
blake-poems.txt', bryant-stories.txt', burgess-busterbrown.txt',
carroll-alice.txt', chesterton-ball.txt', chesterton-brown.txt', 
chesterton-thursday.txt', edgeworth-parents.txt', melville-moby_dick.txt',
milton-paradise.txt', shakespeare-caesar.txt', shakespeare-hamlet.txt',
shakespeare-macbeth.txt', whitman-leaves.txt']

Accessing Raw Text

We can access the raw text from these files using sent_tokenize function which is also available in nltk. In the below example we retrieve the first two paragraphs of the blake poen text.

main.py

from nltk.tokenize import sent_tokenize
from nltk.corpus import gutenberg

sample = gutenberg.raw("blake-poems.txt")

token = sent_tokenize(sample)

for para in range(2):
    print(token[para])

Output

When we run the above program we get the following output −

[Poems by William Blake 1789]

 
SONGS OF INNOCENCE AND OF EXPERIENCE
and THE BOOK of THEL


 SONGS OF INNOCENCE
 
 
 INTRODUCTION
 
 Piping down the valleys wild,
   Piping songs of pleasant glee,
 On a cloud I saw a child,
   And he laughing said to me:
 
 "Pipe a song about a Lamb!"
So I piped with merry cheer.