Ty = Sequence(Segment[(0, t, -0.1), (0, t, 0.1)], t, 1, 6)
Tx = Sequence(Segment[(t, 0, -0.1), (t, 0, 0.1)], t, 1, 6)
Tz = Sequence(Segment[(0, -0.1, t), (0, 0.1, t)], t, 1, 6)
u = Vector((0, 0, 0), (7, 0, 0))
w = Vector((0, 0, 0), (0, 0, 7))
v = Vector((0, 0, 0), (0, 7, 0))
a = Sphere((0, 0, 0), 4)
P = (-1, 2, 3.3166247903554)
z = Vector((0, 0, 0), P)