def test_smape_is_symmetric(self):
y_true = np.random.random(10)
y_pred = np.random.random(10)
first_error = smape(y_true, y_pred)
second_error = smape(y_pred, y_true)
assert first_error == second_error
def test_correct_smape_list(self):
y_true = [0, 1, 2, 3, 4, 5]
y_pred = [3, 2, 4, 3, 5, 7]
error = smape(y_true, y_pred)
expected_error = (1 + 1 / 3 + 1 / 3 + 0 + 1 / 9 + 1 / 6) * (2 / 6)
assert expected_error == error
def test_correct_smape_dataframe(self):
y_true = pd.DataFrame([0, 1, 2, 3, 4, 5])
y_pred = pd.DataFrame([3, 2, 4, 3, 5, 7])
error = smape(y_true, y_pred)
expected_error = (1 + 1 / 3 + 1 / 3 + 0 + 1 / 9 + 1 / 6) * (2 / 6)
assert expected_error == error
def test_correct_smape_array(self):
y_true = np.array([0, 1, 2, 3, 4, 5])
y_pred = np.array([3, 2, 4, 3, 5, 7])
error = smape(y_true, y_pred)
expected_error = (1 + 1 / 3 + 1 / 3 + 0 + 1 / 9 + 1 / 6) * (2 / 6)
assert expected_error == error
def test_smape_random_arrays(self, y_true, y_pred):
error = smape(y_true, y_pred)
expected_error = self._correct_smape(y_true, y_pred)
assert expected_error == error
def test_between_zero_and_one(self, y_true, y_pred):
error = smape(y_true, y_pred)
assert error >= 0
assert error <= 2
def test_infinite_values(self):
y_true = np.random.random(4)
y_pred = np.array([0, np.inf, 2, 3])
with pytest.raises(ValueError):
smape(y_true, y_pred)
def test_nan_values(self):
y_true = np.array([np.nan, 1, 2, 3])
y_pred = np.random.random(4)
with pytest.raises(ValueError):
smape(y_true, y_pred)
def test_wrong_vector_length(self):
y_true = np.random.random(5)
y_pred = np.random.random(4)
with pytest.raises(ValueError):
smape(y_true, y_pred)