Hi Wolfram,

I have two suggestions.  First, my line numbers don't match yours for yt/data_objects/data_containers.py. This means that you're not on the latest development version of yt.  I would first try updating to the latest development version:

$ cd $YT_HG
$ hg pull
$ hg up yt
$ python setup.py build_ext -i

and then try your script again. If the issue isn't fixed by updating, I would then try applying the following diff to the nyx frontend:

diff -r f936432ed45d yt/frontends/nyx/data_structures.py
--- a/yt/frontends/nyx/data_structures.py       Tue Jul 30 10:08:24 2013 -0700
+++ b/yt/frontends/nyx/data_structures.py       Tue Aug 06 08:10:25 2013 -0700
@@ -611,7 +611,7 @@
         # aliases we need
         self.parameters["TopGridRank"] = len(self.parameters["TopGridDimensions"]
         self.dimensionality = self.parameters["TopGridRank"]
-        self.domain_dimensions = self.parameters["TopGridDimensions"]
+        self.domain_dimensions = np.array(self.parameters["TopGridDimensions"])
         self.refine_by = self.parameters.get("RefineBy", 2)  # 2 is silent defaul

         # Nyx is always cosmological.

If you take a look at the enzo frontend, EnzoStaticOutput.domain_dimensions will always be a numpy array, for which an astype method is well defined.  If that fixes your issue, would you mind submitting the patch as a pull request?  There's more information about submitting changes in the yt docs: http://yt-project.org/docs/2.5/advanced/developing.html#making-and-sharing-changes



On Tue, Aug 6, 2013 at 2:29 AM, Wolfram Schmidt <schmidt@astro.physik.uni-goettingen.de> wrote:

I have got problem that concerns Nyx users and/or yt developers.

I want to read the root-grid level from AMR data sets with the following piece of code:

resolution = (right-left)/pf.h.grids[0]['dx']+2*num_ghost_zones
cg = pf.h.covering_grid(0,left,resolution,num_ghost_zones=num_ghost_zones)

This works for Enzo data sets, but it fails for Nyx data sets. The error message is

Traceback (most recent call last):
  File "/home/h/nipiagws/scripts/spect_sb.py", line 52, in <module>
    cg = pf.h.covering_grid(0,left,resolution,num_ghost_zones=num_ghost_zones)
  File "/home/h/nipschul/yt-x86_64/src/yt-hg/yt/data_objects/data_containers.py", line 3727, in __init__
    self.dds = self.pf.domain_width/rdx.astype("float64")
AttributeError: 'list' object has no attribute 'astype'

The script used to work also for Nyx data sets, with an older version of yt (about a year ago).

How can this be fixed?

Thanks a lot,
yt-users mailing list