def test_polar_decomposition(self):
"""F = RU = VR."""
F = np.broadcast_to(np.eye(3), [self.n, 3, 3]) * np.random.rand(
self.n, 3, 3)
R = mechanics.rotation(F).as_matrix()
V = mechanics.stretch_left(F)
U = mechanics.stretch_right(F)
assert np.allclose(np.matmul(R, U), np.matmul(V, R))
def test_add_stretch_left(self, default):
default.add_stretch_tensor('F', 'V')
in_memory = mechanics.stretch_left(default.place('F'))
in_file = default.place('V(F)')
assert np.allclose(in_memory, in_file)