Also in the next major release of yt there will be much richer support for saving derived data and working with it locally using the new ytdata frontend that Britton Smith has put in. If you're interested in playing with that, I'm sure feedback would be very much appreciated. I can give you more information offline about how to set up a development version of yt including Britton's pull request.

https://bitbucket.org/yt_analysis/yt/pull-requests/1788/adding-ytdata-frontend

On Tue, Oct 20, 2015 at 10:55 AM, Matthew Turk <matthewturk@gmail.com> wrote:
Oops, make that:

f.create_dataset("/density", data=cg["Density"])

On Tue, Oct 20, 2015 at 10:45 AM, Dave Semeraro
<semeraro@tacc.utexas.edu> wrote:
> Ok that didn’t work.
>
>>>> f = h5py.File("density","w")
>>>> f.create_dataset("/density",cg["Density"])
> Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
>   File "/work/01197/semeraro/maverick/yt-x86_64/lib/python2.7/site-packages/h5py-2.3.1-py2.7-linux-x86_64.egg/h5py/_hl/group.py", line 94, in create_dataset
>     dsid = dataset.make_new_dset(self, shape, dtype, data, **kwds)
>   File "/work/01197/semeraro/maverick/yt-x86_64/lib/python2.7/site-packages/h5py-2.3.1-py2.7-linux-x86_64.egg/h5py/_hl/dataset.py", line 112, in make_new_dset
>     sid = h5s.create_simple(shape, maxshape)
>   File "h5s.pyx", line 91, in h5py.h5s.create_simple (h5py/h5s.c:1377)
>   File "utils.pyx", line 132, in h5py.utils.convert_tuple (h5py/utils.c:2023)
> TypeError: Can't convert element 0 ([[ 0.11706294  0.11706294  0.11706294 ...,  0.03951106  0.03951106
>
>> -----Original Message-----
>> From: yt-users [mailto:yt-users-bounces@lists.spacepope.org] On Behalf Of
>> Matthew Turk
>> Sent: Tuesday, October 20, 2015 12:33 PM
>> To: Discussion of the yt analysis package <yt-users@lists.spacepope.org>
>> Subject: Re: [yt-users] writing out covering grid.
>>
>> Hi Dave,
>>
>> (Nice to hear from you!)  Yes, it's possible, although I have a suspicion why you
>> want to.  ;-)  You can do this with h5py much more
>> easily:
>>
>> import h5py
>> f = h5py.File("something", "w")
>> f.create_dataset("/density", cg["Density"])
>> f.close()
>>
>> If you do it with cg["density"] it'll be in CGS, not code units.
>>
>> -Matt
>>
>> On Tue, Oct 20, 2015 at 10:30 AM, Dave Semeraro
>> <semeraro@tacc.utexas.edu> wrote:
>> > Hello,
>> >
>> >
>> >
>> > I have created a covering grid from a sample Enzo dataset. I would
>> > like to write the “density” field to a file. I am doing the following
>> > but getting an error.
>> >
>> >
>> >
>> > cg = ds.covering_grid(3,[0.,0.,0.],ds.domain_dimensions*2**2)
>> >
>> >
>> >
>> > cg.write_out("spoot","Density")
>> >
>> >
>> >
>> > Traceback (most recent call last):
>> >
>> >   File "<stdin>", line 1, in <module>
>> >
>> >   File
>> > "/work/01197/semeraro/maverick/yt-x86_64/src/yt-hg/yt/data_objects/dat
>> > a_containers.py",
>> > line 399, in write_out
>> >
>> >     field_data = np.array([self.field_data[field] for field in
>> > field_order])
>> >
>> > KeyError: 'x'
>> >
>> >
>> >
>> > Is it possible to write out the single field to a file from a covering grid?
>> >
>> >
>> >
>> > DAve
>> >
>> >
>> > _______________________________________________
>> > yt-users mailing list
>> > yt-users@lists.spacepope.org
>> > http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>> >
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