def test_cosine_similarity():
"""Cosine similarity calculations are correct."""
data_a = [2, 1, 0, 2, 0, 1, 1, 1]
data_b = [2, 1, 1, 1, 1, 0, 1, 1]
sim_score = similarity.cosine(data_a, data_b)
assert round(sim_score, 3) == 0.822
def test_cosine_empty():
"""Cosine between two empty lists is zero."""
assert similarity.cosine([], []) == 0
