Lattice.get_coordinates does not properly support 'hexagonal' lattices

[itziakos]

looking at the implementation of Lattice.get_ccordinates https://github.com/simphony/simphony-common/blob/master/simphony/cuds/lattice.py#L116 it looks that providing the x,y,x coordinates of hexagonal lattice nodes is not supported.

Given that the Lattice api is going to change soon, I suggest to raise a NotImplementedError in when Lattice.type == 'Hexagonal' to make sure that user are informed of the current issue.

[roigcarlo]

@tuopuu Can you pick this up for the next milestone?

[nathanfranklin]

@kemattil , see @roigcarlo 's comment above

[itziakos]

It looks that the hdf5 implementation of the Lattice also suffers from this problem

[tuopuu]

Yes, I can pick this one up. We're going to work on number of issues in the Lattice systems.

[kemattil]

@tuopuu, for fixing this issue, add only the NotImplementedError. Before implementing/fixing the other issues, we have to discuss them in SSB (I'm preparing a memo).

[itziakos]

removing SSB label since the related API changes to the Lattice description have been approved