Hi all,

Matt asked someone to send a quick note about the current issues regarding the ytdata frontend PR:


I’m sending it because I’m working on it currently, but I was not able to attend today’s PR hangout so anyone else who was more to add or to correct should chime in. 

Currently, there are 3 issues, from most important to least important:

1. Tests don’t work
2. Doesn’t support Python 3
3. Derived quantities don’t work

I’m currently working on 1 and 2, and there have been some ideas about 3. The main issue with the latter is that for non-gridded data containers (like sphere, disk, etc.) created from grid datasets, we treat the new datasets as “particle data”. For that reason there is an issue with calculating the cell_volume properly. Without that, we cannot use the total_mass() quantity. Given that we have the cell deltas in the dataset, we could have a special derived field for the cell_volume. 

There are other issues with some of the other derived quantities (e.g., weighted_average_quantity returning the wrong units), but I haven’t been able to diagnose them yet. 

I’m working on some changes that will need to be merged into Britton’s fork eventually to address at least 1 and 2.