I ran a 2D simulation with Athena and exported the data to vtk files. I was even able to load the file with yt and inspect some of its elements. What I would like to do is to compare the density from the simulation to an analytic solution (which I can evaluate at the grid points). The problem is I cannot figure out how to extract the relevant information from the yt.frontends.athena.data_structures.AthenaDataset object. What I expect are 2d arrays of the x coordinate, y coordinate and density.