I can reproduce this and have filed an issue about it: https://bitbucket.org/yt_analysis/yt/issues/1070/cannot-access-field-that-ne... Unfortunately I don't have a workaround yet... On Fri, Aug 21, 2015 at 7:11 AM, Markus Haider <markus.haider@uibk.ac.at> wrote:

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 _______________________________________________ yt-users mailing list yt-users@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org

On 08/21/2015 10:08 AM, Nathan Goldbaum wrote:

I can reproduce this and have filed an issue about it:

https://bitbucket.org/yt_analysis/yt/issues/1070/cannot-access-field-that-ne...

Unfortunately I don't have a workaround yet...

Hi Markus, until this is fixed properly, you can pass 'num_ghost_zones=1' to covering_grid() manually. This will allow you to access fields that are using derivatives. Cheers, Kacper

On Fri, Aug 21, 2015 at 7:11 AM, Markus Haider <markus.haider@uibk.ac.at> wrote:

...

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 _______________________________________________ yt-users mailing list yt-users@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org

_______________________________________________ yt-users mailing list yt-users@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org