Basic vector code, without a coordinate system class

All calculations essentially occur in the same frame.
i, j, k and x, y, z are imported as base vectors and base scalars by default on importing sympy.vector.
delop is a Del operator instance.

Example:

>>> v = 3*i - j
>>> delop ^ v
0

(delop ^ v represents curl of v)
No. This is a unit vector yes, but a unit vector is any vector with magnitude = 1. A base vector or a basis vector is a unit vector along one of the 'axes' of a coordinate system. So BaseVector makes more sense, naming wise.