I'm trying to obtain the maximum and minimum level of refinement of a data container in a simulation. What I am doing is the following:

ds=yt.load(bname)
sp_open=ds.disk(center,normal,radius,(res,'pc')) # smallest disk possible

Where bname is the name of the snapshot, center, normal, radius, and res, are the desired center, normal, radius  and height of the disk. I chose the resolution of the simulation as the height of the disk because I want it to represent a disk-like differential area and I the disk is located at the region of highest level of refinement.

I tried to obtain the minimum and maximum levels of refinement over the sp_open subregion, however only max_level is implemented doing:

sp_open.index.max_level

Do you know how I can obtain the minimum level of refinement of a data container of a sub-region?

Besides, when I print the level statistics of the subregion and the ones of the whole computational volume I get the same output. I print them using:

sp_open.index.level_stats # subregion
ds.index.level_stats   # computational volume

And I get:
rec.array([(    1,      512,  0), (    8,     4096,  1),
           (   64,    32768,  2), (  512,   262144,  3),
           ( 4096,  2097152,  4), (32768, 16777216,  5),
           (    0,        0,  6), (    0,        0,  7),
           (    0,        0,  8), (    0,        0,  9),
           (    0,        0, 10), (    0,        0, 11),
           (    0,        0, 12), (    0,        0, 13),
           (    0,        0, 14), (    0,        0, 15),
           (    0,        0, 16), (    0,        0, 17),
           (    0,        0, 18), (    0,        0, 19),
           (    0,        0, 20), (    0,        0, 21),
           (    0,        0, 22), (    0,        0, 23),
           (    0,        0, 24), (    0,        0, 25),
           (    0,        0, 26), (    0,        0, 27),
           (    0,        0, 28), (    0,        0, 29),
           (    0,        0, 30), (    0,        0, 31),
           (    0,        0, 32), (    0,        0, 33),
           (    0,        0, 34), (    0,        0, 35),
           (    0,        0, 36), (    0,        0, 37),
           (    0,        0, 38), (    0,        0, 39),
           (    0,        0, 40), (    0,        0, 41),
           (    0,        0, 42), (    0,        0, 43),
           (    0,        0, 44), (    0,        0, 45),
           (    0,        0, 46), (    0,        0, 47)],
          dtype=[('numgrids', '<i8'), ('numcells', '<i8'), ('level', '<i8')])

Which does not make sense to me, because the sub-region level statistics should not include coarse grids, even though this sub-region is in fact inside lower refinement regions.

Shouldn't this statistics just print the lowest and highest refinement level inside the sub-region ?

Thank you,
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