def test_entropy_notarray():
probs = [0.5, 0.5]
with pytest.raises(ValueError) as excinfo:
entropy(probs)
assert 'Probs should be a numpy array' in str(excinfo.value)
def test_entropy_with_zero():
probs = np.array([0, 0.3, 0.7])
e = entropy(probs)
np.testing.assert_almost_equal(e, 0.26529499557412151)
def test_entropy_fourclass():
probs = np.array([0.1, 0.1, 0.1, 0.7])
e = entropy(probs)
np.testing.assert_almost_equal(e, 0.4084313719900203)
def test_entropy_binary():
probs = np.array([0.2, 0.8])
e = entropy(probs)
np.testing.assert_almost_equal(e, 0.21732201127364886)
def test_entropy_threeclass():
probs = np.array([0.1, 0.3, 0.6])
e = entropy(probs)
np.testing.assert_almost_equal(e, 0.3899728733539152)