have custom Grid throw error if spacing or weights is called when it was not passed in

[dpanici]

No description provided.

[unalmis]

The idea is that, if we are assigning these automatically, we should assign uniform spacing / uniform weights if the user doesn't pass them in. While we can compute the weights to be uniform automatically, it is not possible to compute uniform spacing without additional information. To get uniform spacing you would need to do:

DESC/desc/equilibrium/coords.py

Line 318 in b10070e

spacing = jnp.array([1 / rho.size, 2 * jnp.pi / t.size, 2 * jnp.pi / z.size])[

which requires knowing the number of unique surfaces. Had I not explicitly passed in this spacing, then the computation would be incorrect and it would take long to debug. Others may forget, so we should throw an error unless spacing is passed in explicitly.

[unalmis]

And then also delete this chunk, since it is an identity operation for the non-custom grids anyway, and we shouldn't modify spacing if it is passed in by the user.

DESC/desc/grid.py

Line 174 in 5801ea8

if (self.spacing.T * duplicates ** (1 / 6)).prod(axis=0).sum():