Comment functions better

bayes.py

@@ -35,21 +35,30 @@ After training (which is run before your code), the following 3 global variables
     num_data_points_in_category[category] = Total number of documents in the category 'category'
 """
 @cache
-def pr_category(category : str) : # Pr(category)
+def pr_category(category : str):
+    """
+    Computes Pr(category)
+    """
     return 0
 
 @cache
-def pr_word_given_category(word : str, category : str, num_words_in_document : int): # Pr(word | category)
+def pr_word_given_category(word : str, category : str, num_words_in_document : int): 
+    """
+    Computes Pr(word | category)
+    """
     return 0
 
-def pr_category_given_words(words : List[str], category : str): # Pr(category | words)
+def log_pr_category_given_words(words : List[str], category : str):
+    """
+    Computes log(Pr(category | words))
+    """
     return 0
 
 def predict(categories, words):
     best = None
     best_likelihood = -inf
     for category in categories:
-        pr = pr_category_given_words(words, category)
+        pr = log_pr_category_given_words(words, category)
         if  pr > best_likelihood:
             best = category
             best_likelihood = pr