def test_area_under_curve_non_numpy_arrays():
"""Ensure that an error is raised when x and y are not numpy arrays"""
x = [0., 1., 2., 3.]
y = [0., 2., 4., 6.]
with pytest.raises(PSDSEvalError,
match="must be provided as a numpy.ndarray"):
PSDSEval._auc(x, y)
def test_area_under_curve_with_2d_arrays():
"""Ensure that an error is raised when x and y are not 1-Dimensional"""
x = np.random.randint(0, 5, (5, 5))
y = np.random.randint(0, 5, (2, 2))
with pytest.raises(PSDSEvalError,
match="x or y are not 1-dimensional numpy.ndarray"):
PSDSEval._auc(x, y)
def test_area_under_curve_with_mismatched_arrays():
"""Check an error is thrown when x and y are unequal in length"""
x = np.array([0.9, 1.8, 2.7, 3.6, 4.5])
y = np.array([1.1, 2, 3, 4, 5, 7])
with pytest.raises(PSDSEvalError,
match="x and y must be of equal length 5 != 6"):
PSDSEval._auc(x, y)
def test_area_under_y_not_monotonically_increasing():
"""Ensure an error is raised when y is an increasing series"""
x = np.array([0, 1, 2, 3, 4, 5])
y = np.array([5, 4, 2, 1, 0.5, 0])
with pytest.raises(PSDSEvalError,
match="non-decreasing property not verified for y"):
PSDSEval._auc(x, y)
def test_area_under_x_not_monotonically_increasing():
"""Ensure that an error is thrown when x is an increasing series"""
x = np.array([5, 4, 2, 1, 0.5])
y = np.array([1, 2, 3, 4, 5])
with pytest.raises(PSDSEvalError,
match="non-decreasing property not verified for x"):
PSDSEval._auc(x, y)
with pytest.raises(PSDSEvalError,
match="non-decreasing property not verified for x"):
PSDSEval._auc(x, y)
def test_area_under_y_not_monotonically_increasing_allow_decrease_y():
"""Ensure the auc is computed correctly when y is not non-decreasing but
the flag allow_decrease_y is set to True"""
x = np.array([0, 1, 2, 3, 4])
y = np.array([1.1, 2.3, 4.2, 3.5, 5.5])
auc = PSDSEval._auc(x, y, decreasing_y=True)
assert auc == pytest.approx(11.1), "The area calculation was incorrect"
def test_simple_area_under_curve():
"""Ensure that the area under a curve function produces the correct area"""
x = np.array([0, 1, 2])
y = np.array([1, 2, 3])
auc = PSDSEval._auc(x, y)
assert auc == pytest.approx(3.0), "The area calculation was incorrect"
def test_simple_area_under_curve_with_max():
"""Ensure area calculation is correct when a max_x value is specified"""
x = np.array([0, 1, 2, 3, 4])
y = np.array([1.1, 2.3, 3.5, 4.2, 5.5])
auc = PSDSEval._auc(x, y, max_x=2)
assert auc == pytest.approx(3.4), "The area calculation was incorrect"
