Source code for nltk.test.unit.test_cfd_mutation

import unittest
from nltk import ConditionalFreqDist, tokenize

[docs]class TestEmptyCondFreq(unittest.TestCase):
[docs] def test_tabulate(self): empty = ConditionalFreqDist() self.assertEqual(empty.conditions(),[]) try: empty.tabulate(conditions="BUG") # nonexistent keys shouldn't be added except: pass self.assertEqual(empty.conditions(), [])
[docs] def test_plot(self): empty = ConditionalFreqDist() self.assertEqual(empty.conditions(),[]) try: empty.plot(conditions=["BUG"]) # nonexistent keys shouldn't be added except: pass self.assertEqual(empty.conditions(),[])
[docs] def test_increment(self): # make sure that we can still mutate cfd normally text = "cow cat mouse cat tiger" cfd = ConditionalFreqDist() # create cfd with word length as condition for word in tokenize.word_tokenize(text): condition = len(word) cfd[condition][word] += 1 self.assertEqual(cfd.conditions(), [3,5]) # incrementing previously unseen key is still possible cfd[2]['hi'] += 1 self.assertEqual(set(cfd.conditions()),set([3,5,2])) # new condition added self.assertEqual(cfd[2]['hi'], 1) # key's frequency incremented from 0 (unseen) to 1