[yt-users] covering_grid question

[Elizabeth Tasker]

Hi all,

When I extract a patch of my simulation as a uniform mesh using covering_grid, what happens if the arguments are incompatible? For example:


cubit = pf.h.covering_grid(4, 
                               left_edge=extract_leftedge,
                               right_edge=extract_rightedge,
                       	       dims=extract_dims,
                               fields=["PotentialField"])

If I specify both the left and right edge, then the dimensions of the extracted region and the required level of the extraction are not independent. So I could ask for dimensions that are larger or smaller than a grid of that size at that level; does the code extract to the desired level and then interpolate, or does it ignore one of the settings?

Also, am I good to assume that left and right edge do not need to be exactly on a grid boundary, but yt will shift them slightly so they fit?

Thank you!

Elizabeth