def test_quaternion_product():
"""Test equivalence with generating combined rotations using rotation matrices."""
qp_x90_y90 = generate.quaternion_product(cst.quatx90, cst.quaty90)
qp_y90_z90 = generate.quaternion_product(cst.quaty90, cst.quatz90)
qp_z90_z90 = generate.quaternion_product(cst.quatz90, cst.quatz90)
assert np.allclose(convert.quaternion2rot3d(qp_x90_y90),
cst.Rx90.dot(cst.Ry90))
assert np.allclose(convert.quaternion2rot3d(qp_y90_z90),
cst.Ry90.dot(cst.Rz90))
assert np.allclose(convert.quaternion2rot3d(qp_z90_z90),
cst.Rz90.dot(cst.Rz90))
def test_quat2rot2quat():
"""Test quaternion2rot3d and rotmat_to_quaternion consistency."""
n = 1000
orientations = generate.get_random_quat(n)
for i in range(n):
orientation = orientations[i]
rot = convert.quaternion2rot3d(orientation)
quat = convert.rotmat_to_quaternion(rot)
assert np.allclose(orientation, quat) \
or np.allclose(orientation, -quat)
def test_quaternion2rot3d_invariant():
"""Test the invariance of quaternion2rot3d.
Test the invariance property of the rotation axis on randomly
selected axes.
"""
n = 1000
orientations = generate.get_random_quat(n)
for i in range(n):
orientation = orientations[i]
rot = convert.quaternion2rot3d(orientation)
rotated = np.dot(rot, orientation[1:])
assert np.allclose(rotated, orientation[1:])
def test_quaternion2rot3d_z():
"""Test quaternion2rot3d for 90deg rotations along z."""
rot90 = convert.quaternion2rot3d(cst.quatz90)
assert np.allclose(rot90, cst.Rz90)
def test_quaternion2rot3d_y():
"""Test quaternion2rot3d for 90deg rotations along y."""
rot90 = convert.quaternion2rot3d(quaty90)
assert np.allclose(rot90, Ry90)