Hello yt-users, I have a question about the disk data object. The first input it needs is center, which according to your website is the coordinates of the geometrical center of the disk on the simulation length units. So, the center of the computational domain is c=[0.5,0.5,0.5]. I set the center of two different cylinders in a way that they don’t overlap. The axis of these cylinders are parallel to the x axis and one is on the negative X coordinate region while the other one on the positive region. But, I found that they actually have exactly the same cell centers. Did I do something wrong? On the following code the box side is 256 pc, so the center of the first disk c_1=[0.25,0.5,0.5] with a height of 32 pc does not overlap with the second disk of center c_2=[0.75,0.5,0.5] also with height 32 pc. http://paste.yt-project.org/show/275/ I’m using : --- Version = 3.6.dev0 And the snapshot used is here: http://use.yt/upload/c58a4c0f -- Guido