[yt-users] Vorticity field with FLASH

Hi, I was trying to calculate the vorticity for a flash dataset. I selected a region using center = (ad.quantities.min_location('gpot')[2],ad.quantities.min_location('gpot')[3],ad.quantities.min_location('gpot')[4]) LE = center-width.in_units('code_length')/2. CN = int(width/dx) Roi = ds.covering_grid(level=level_max,left_edge=LE, dims=[CN,CN,CN]) Then, for this region I wanted to compute the vorticity using Roi["gas","vorticity_x"] This resulted in the following error: http://paste.yt-project.org/show/5824/ Thanks for your help, Cheers, Markus