In [1]:
%matplotlib inline
from matplotlib import pyplot as plt
import numpy as np
Write a function tokenize
that takes a string of English text returns a list of words. It should also remove stop words, which are common short words that are often removed before natural language processing. Your function should have the following logic:
splitlines
.filter
function to remove all punctuation.stop_words
is a list, remove all occurences of the words in the list.stop_words
is a space delimeted string of words, split them and remove them.
In [2]:
file = open('mobydick_chapter1.txt')
mobydick = file.read()
mobydick.splitlines()
mobydick.split()
print (len(mobydick.split()))
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def tokenize(s, stop_words=None, punctuation='`~!@#$%^&*()_-+={[}]|\:;"<,>.?/}\t'):
lines = s.splitlines()
i = 0
empty = []
while i < len.lines:
empty.extend(lines[i].split())
i += 1
a = []
b = 0
while b < len(empty):
a.append(''.join([c for c in empty[b] if c not in punctuation]))
b += 1
for g in a:
g.lower()
c = 0
d = []
while c < len(h):
d.append(''.join([e for e in h[c] if h[c] not in stop_words]))
c+=1
answer = list(filter(None,d))
return answer
"""Split a string into a list of words, removing punctuation and stop words."""
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assert tokenize("This, is the way; that things will end", stop_words=['the', 'is']) == \
['this', 'way', 'that', 'things', 'will', 'end']
wasteland = """
APRIL is the cruellest month, breeding
Lilacs out of the dead land, mixing
Memory and desire, stirring
Dull roots with spring rain.
"""
assert tokenize(wasteland, stop_words='is the of and') == \
['april','cruellest','month','breeding','lilacs','out','dead','land',
'mixing','memory','desire','stirring','dull','roots','with','spring',
'rain']
Write a function count_words
that takes a list of words and returns a dictionary where the keys in the dictionary are the unique words in the list and the values are the word counts.
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def count_words(data):
"""Return a word count dictionary from the list of words in data."""
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assert count_words(tokenize('this and the this from and a a a')) == \
{'a': 3, 'and': 2, 'from': 1, 'the': 1, 'this': 2}
Write a function sort_word_counts
that return a list of sorted word counts:
(word, count)
tuple.sorted
function with a custom key
and reverse
argument.
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"""Return a list of 2-tuples of (word, count), sorted by count descending."""
Out[7]:
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assert sort_word_counts(count_words(tokenize('this and a the this this and a a a'))) == \
[('a', 4), ('this', 3), ('and', 2), ('the', 1)]
Perform a word count analysis on Chapter 1 of Moby Dick, whose text can be found in the file mobydick_chapter1.txt
:
'the of and a to in is it that as'
.swc
.
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assert swc[0]==('i',43)
assert len(swc)==848
Create a "Cleveland Style" dotplot of the counts of the top 50 words using Matplotlib. If you don't know what a dotplot is, you will have to do some research...
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assert True # use this for grading the dotplot