def test_parallel_axis():
N = ReferenceFrame('N')
m, a, b = symbols('m, a, b')
o = Point('o')
p = o.locatenew('p', a * N.x + b * N.y)
P = Particle('P', o, m)
Ip = P.parallel_axis(p, N)
Ip_expected = inertia(N, m * b**2, m * a**2, m * (a**2 + b**2),
ixy=-m * a * b)
assert Ip == Ip_expected
def test_parallel_axis():
N = ReferenceFrame("N")
m, a, b = symbols("m, a, b")
o = Point("o")
p = o.locatenew("p", a * N.x + b * N.y)
P = Particle("P", o, m)
Ip = P.parallel_axis(p, N)
Ip_expected = inertia(N,
m * b**2,
m * a**2,
m * (a**2 + b**2),
ixy=-m * a * b)
assert Ip == Ip_expected