81 lines
2.0 KiB
Python
Executable File
81 lines
2.0 KiB
Python
Executable File
#!/usr/bin/env python
|
|
import sys, re, operator, string
|
|
from functools import reduce
|
|
|
|
try:
|
|
xrange # Python 2
|
|
except NameError:
|
|
xrange = range # Python 3
|
|
|
|
|
|
#
|
|
# Functions for map reduce
|
|
#
|
|
def partition(data_str, nlines):
|
|
"""
|
|
Partitions the input data_str (a big string)
|
|
into chunks of nlines.
|
|
"""
|
|
lines = data_str.split('\n')
|
|
for i in xrange(0, len(lines), nlines):
|
|
yield '\n'.join(lines[i:i+nlines])
|
|
|
|
def split_words(data_str):
|
|
"""
|
|
Takes a string, returns a list of pairs (word, 1),
|
|
one for each word in the input, so
|
|
[(w1, 1), (w2, 1), ..., (wn, 1)]
|
|
"""
|
|
def _scan(str_data):
|
|
pattern = re.compile('[\W_]+')
|
|
return pattern.sub(' ', str_data).lower().split()
|
|
|
|
def _remove_stop_words(word_list):
|
|
with open('../stop_words.txt') as f:
|
|
stop_words = f.read().split(',')
|
|
stop_words.extend(list(string.ascii_lowercase))
|
|
return [w for w in word_list if not w in stop_words]
|
|
|
|
# The actual work of splitting the input into words
|
|
result = []
|
|
words = _remove_stop_words(_scan(data_str))
|
|
for w in words:
|
|
result.append((w, 1))
|
|
return result
|
|
|
|
def count_words(pairs_list_1, pairs_list_2):
|
|
"""
|
|
Takes two lists of pairs of the form
|
|
[(w1, 1), ...]
|
|
and returns a list of pairs [(w1, frequency), ...],
|
|
where frequency is the sum of all the reported occurrences
|
|
"""
|
|
mapping = {}
|
|
for pl in [pairs_list_1, pairs_list_2]:
|
|
for p in pl:
|
|
if p[0] in mapping:
|
|
mapping[p[0]] += p[1]
|
|
else:
|
|
mapping[p[0]] = p[1]
|
|
return mapping.items()
|
|
|
|
#
|
|
# Auxiliary functions
|
|
#
|
|
def read_file(path_to_file):
|
|
with open(path_to_file) as f:
|
|
data = f.read()
|
|
return data
|
|
|
|
def sort(word_freq):
|
|
return sorted(word_freq, key=operator.itemgetter(1), reverse=True)
|
|
|
|
#
|
|
# The main function
|
|
#
|
|
splits = map(split_words, partition(read_file(sys.argv[1]), 200))
|
|
word_freqs = sort(reduce(count_words, splits))
|
|
|
|
for (w, c) in word_freqs[0:25]:
|
|
print(w, ' - ', c)
|