def test_cosine_similarity_similar_vectors_2d(self):
"""Should return 1 for vectors pointing in same directions"""
v1 = (1, 1)
v2 = (2, 2)
self.assertAlmostEqual(cosine_similarity(v1, v2), 1, 9)
def test_cosine_similarity_similar_vectors_3d_lists(self):
"""Should compute cosine similarity regardless vector representation or dimension"""
v1 = [1, 1, 1]
v2 = [2, 2, 2]
self.assertAlmostEqual(cosine_similarity(v1, v2), 1, 9)
def test_cosine_similarity_opposite_vectors_2d(self):
"""Should return -1 for vectors pointing in opposite directions"""
v1 = (1, 1)
v2 = (-2, -2)
self.assertAlmostEqual(cosine_similarity(v1, v2), -1, 9)
def test_cosine_similarity_floating_point_rounding_error_negative(self):
"""Should return -1 as minimum in case of floating point rounding errors"""
v1 = (0.0000015006504264572506635033732891315594, 0.0000006050474740115774352489097509533167)
v2 = (-0.0000015006504264503117695994660607539117, -0.0000006050474739005551327863940969109535)
self.assertTrue(cosine_similarity(v1, v2) >= -1)
def test_cosine_similarity_orthogonal_vectors_2d(self):
"""Should return 0 for orthogonal vectors"""
v1 = (1, 1)
v2 = (2, -2)
self.assertAlmostEqual(cosine_similarity(v1, v2), 0, 9)