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)
This seems applicable. If you component is a polynomial, seems like you should be able to factor it. Why don't you implement this?

You should `NotImplementedError`, not `TypeError`.