Frequency analysis toolbox

frequency.py

@@ -1,15 +1,30 @@
 """ Analyzes the word frequencies in a book downloaded from
-	Project Gutenberg """
+	Project Gutenberg. I downloaded Moby Dick, because it is maybe the most
+	boring book ever. Looks like 'whale' is definitely within the 100 most
+	used words."""
 
 import string
 
 def get_word_list(file_name):
-	""" Reads the specified project Gutenberg book.  Header comments,
-		punctuation, and whitespace are stripped away.  The function
-		returns a list of the words used in the book as a list.
-		All words are converted to lower case.
-	"""
-	pass
+    """ Reads the specified project Gutenberg book.  Header comments,
+        punctuation, and whitespace are stripped away.  The function
+        returns a list of the words used in the book as a list.
+        All words are converted to lower case.
+    """
+    f = open(file_name, 'r')
+    lines = f.readlines()
+    curr_line = 0
+    while lines[curr_line].find('START OF THIS PROJECT GUTENBERG EBOOK') == -1:
+        curr_line += 1
+    lines = lines[curr_line+1:]
+    word_list = []
+
+    for line in lines:
+        line_list = line.split()
+        for word in line_list:
+            word.strip(string.punctuation)
+            word_list.append(word.lower())
+    return word_list
 
 def get_top_n_words(word_list, n):
 	""" Takes a list of words as input and returns a list of the n most frequently
@@ -21,4 +36,13 @@ def get_top_n_words(word_list, n):
 		returns: a list of n most frequently occurring words ordered from most
 				 frequently to least frequentlyoccurring
 	"""
-	pass
+	hist = dict()
+	for word in word_list:
+		hist[word] = hist.get(word,0) + 1
+	ordered_by_frequency = sorted(hist, key=hist.get, reverse=True)
+	return ordered_by_frequency[:n]
+
+
+if __name__ == "__main__":
+	word_list = get_word_list('pg2701.txt')
+	print get_top_n_words(word_list, 100)