Add option to grid_coordinates to return 1D coordinate arrays

[leouieda]

Description of the desired feature:

Currently, verde.grid_coordinates always calls np.meshgrid to produce 2D coordinate arrays. However, when building xarray objects we usually have to undo. That's a bit wasteful can creates problems for very large grids. To counteract this, I propose adding a new meshgrid=True option to grid_coordinates. By default, the behaviour is unchanged. But passing meshgrid=False will return the 1D coordinate arrays instead.

Are you willing to help implement and maintain this feature?

Always but happy for someone else to do this 🙂

[santisoler]

I agree with this! We would need to think what to do with the extra_coords. Any thoughts?

[leouieda]

Good point! It doesn't make sense to use extra_coords and meshgrid=False together since the whole point of extra_coords is to get a meshgrid with constant values. So maybe we just return it as is (i.e. a single value)?

[santisoler]

I agree that if we want to avoid allocating large coordinate arrays it doesn't make sense to generate huge extra_coords arrays with constant values. But it doesn't make any sense either to pass a single float (or list of floats) to extra_coords and get the same ones as output. What if we just avoid the trouble by ignoring extra_coords if we pass meshgrid=False?

[leouieda]

Sounds OK to me. Probably doesn’t matter too much which way we go since using both options together is extremely unlikely (famous last words 🥲).