def test_negative_curvature_unconstrained(self):
H = np.array([[1, 2, 1, 3], [2, 0, 2, 4], [1, 2, 0, 2], [3, 4, 2, 0]])
A = np.array([[1, 0, 1, 0], [0, 1, 0, 1]])
c = np.array([-2, -3, -3, 1])
b = -np.array([3, 0])
Z, _, Y = projections(A)
with pytest.raises(ValueError):
projected_cg(H, c, Z, Y, b, tol=0)
def test_trust_region_infeasible(self):
H = np.array([[6, 2, 1, 3], [2, 5, 2, 4], [1, 2, 4, 5], [3, 4, 5, 7]])
A = np.array([[1, 0, 1, 0], [0, 1, 1, 1]])
c = np.array([-2, -3, -3, 1])
b = -np.array([3, 0])
trust_radius = 1
Z, _, Y = projections(A)
with pytest.raises(ValueError):
projected_cg(H, c, Z, Y, b, trust_radius=trust_radius)
def test_nocedal_example(self):
H = np.array([[6, 2, 1], [2, 5, 2], [1, 2, 4]])
A = np.array([[1, 0, 1], [0, 1, 1]])
c = np.array([-8, -3, -3])
b = -np.array([3, 0])
Z, _, Y = projections(A)
x, info = projected_cg(H, c, Z, Y, b)
assert_equal(info["stop_cond"], 4)
assert_equal(info["hits_boundary"], False)
assert_array_almost_equal(x, [2, -1, 1])
def test_negative_curvature(self):
H = np.array([[1, 2, 1, 3], [2, 0, 2, 4], [1, 2, 0, 2], [3, 4, 2, 0]])
A = np.array([[1, 0, 1, 0], [0, 1, 0, 1]])
c = np.array([-2, -3, -3, 1])
b = -np.array([3, 0])
Z, _, Y = projections(A)
trust_radius = 1000
x, info = projected_cg(H, c, Z, Y, b, tol=0, trust_radius=trust_radius)
assert_equal(info["stop_cond"], 3)
assert_equal(info["hits_boundary"], True)
assert_array_almost_equal(np.linalg.norm(x), trust_radius)
def test_hits_boundary(self):
H = np.array([[6, 2, 1, 3], [2, 5, 2, 4], [1, 2, 4, 5], [3, 4, 5, 7]])
A = np.array([[1, 0, 1, 0], [0, 1, 1, 1]])
c = np.array([-2, -3, -3, 1])
b = -np.array([3, 0])
trust_radius = 3
Z, _, Y = projections(A)
x, info = projected_cg(H, c, Z, Y, b, tol=0, trust_radius=trust_radius)
assert_equal(info["stop_cond"], 2)
assert_equal(info["hits_boundary"], True)
assert_array_almost_equal(np.linalg.norm(x), trust_radius)
def test_trust_region_barely_feasible(self):
H = np.array([[6, 2, 1, 3], [2, 5, 2, 4], [1, 2, 4, 5], [3, 4, 5, 7]])
A = np.array([[1, 0, 1, 0], [0, 1, 1, 1]])
c = np.array([-2, -3, -3, 1])
b = -np.array([3, 0])
trust_radius = 2.32379000772445021283
Z, _, Y = projections(A)
x, info = projected_cg(H, c, Z, Y, b, tol=0, trust_radius=trust_radius)
assert_equal(info["stop_cond"], 2)
assert_equal(info["hits_boundary"], True)
assert_array_almost_equal(np.linalg.norm(x), trust_radius)
assert_array_almost_equal(x, -Y.dot(b))
def test_active_box_constraints_maximum_iterations_reached(self):
H = np.array([[6, 2, 1, 3], [2, 5, 2, 4], [1, 2, 4, 5], [3, 4, 5, 7]])
A = np.array([[1, 0, 1, 0], [0, 1, 1, 1]])
c = np.array([-2, -3, -3, 1])
b = -np.array([3, 0])
Z, _, Y = projections(A)
x, info = projected_cg(H,
c,
Z,
Y,
b,
tol=0,
lb=[0.8, -np.inf, -np.inf, -np.inf],
return_all=True)
assert_equal(info["stop_cond"], 1)
assert_equal(info["hits_boundary"], True)
assert_array_almost_equal(A.dot(x), -b)
assert_array_almost_equal(x[0], 0.8)
def test_active_box_constraints_hits_boundaries_infeasible_iter(self):
H = np.array([[6, 2, 1, 3], [2, 5, 2, 4], [1, 2, 4, 5], [3, 4, 5, 7]])
A = np.array([[1, 0, 1, 0], [0, 1, 1, 1]])
c = np.array([-2, -3, -3, 1])
b = -np.array([3, 0])
trust_radius = 4
Z, _, Y = projections(A)
x, info = projected_cg(H,
c,
Z,
Y,
b,
tol=0,
ub=[np.inf, 0.1, np.inf, np.inf],
trust_radius=trust_radius,
return_all=True)
assert_equal(info["stop_cond"], 2)
assert_equal(info["hits_boundary"], True)
assert_array_almost_equal(x[1], 0.1)