[yt-users] loading cosmological CHANGA data

Nathan Goldbaum nathan12343 at gmail.com
Fri Nov 4 08:25:26 PDT 2016


Hi Christine,

You can load tipsy data with specified cosmological parameters like this:

    cosmology_parameters = {'current_redshift': 0.0,
                                               'omega_lambda': 0.728,
                                               'omega_matter': 0.272,
                                               'hubble_constant': 0.702}

    ds = yt.load(tipsy_filename,
                        cosmology_parameters=cosmology_parameters)

(in general the load function can take any of the keyword arguments
accepted by the TipsyDataset class defined in
yt/frontends/tipsy/data_structures.py)

You're right that the docs should state this explicitly. I've issued a pull
request to update the docs here:

https://bitbucket.org/yt_analysis/yt/pull-requests/2431

-Nathan

On Thu, Nov 3, 2016 at 11:02 PM, B.W. Keller <kellerbw at mcmaster.ca> wrote:

> Hi Christine,
>
> There are some assumptions made by yt when loading data from gasoline
> or changa about  whether a simulation is run with comoving coordinates
> or physical ones.  I developed the tipsy frontend mostly working from
> gasoline outputs, but it should work for changa too (in other words, I
> think you may have found a bug).  Would you be able to upload the
> parameter file you are using for this?  Judging from your file name, I
> assume you are running one of the agora cosmological runs?
>
> Ben
>
> On Thu, Nov 3, 2016 at 8:35 PM, Christine Simpson
> <christine.simpson at gmail.com> wrote:
> > Hi all,
> >
> > I’m trying to load a cosmological snapshot from a Changa simulation
> (which I
> > believe is in the tipsy format).  Yt seems to find some of the
> cosmological
> > parameters but not all of them (not the hubble constant), which messes up
> > the units.  See below.  There is some discussion of cosmology parameters
> and
> > tipsy format in the docs, but I did not understand it.  Can anyone with
> > experience loading this format give me some pointers?
> >
> > Thanks
> > Christine
> >
> > In [1]: pf = load('agora_1e11q_l13.000400')
> > yt : [INFO     ] 2016-11-03 15:17:47,253 Parameters: current_time
> > = 1.61048087203e+23 s
> > yt : [INFO     ] 2016-11-03 15:17:47,253 Parameters: domain_dimensions
> > = [2 2 2]
> > yt : [INFO     ] 2016-11-03 15:17:47,254 Parameters: domain_left_edge
> > = [-0.5 -0.5 -0.5]
> > yt : [INFO     ] 2016-11-03 15:17:47,255 Parameters: domain_right_edge
> > = [ 0.5  0.5  0.5]
> > yt : [INFO     ] 2016-11-03 15:17:47,256 Parameters:
> cosmological_simulation
> > = 1.0
> > yt : [INFO     ] 2016-11-03 15:17:47,256 Parameters: current_redshift
> > = -1.48991929905e-13
> > yt : [INFO     ] 2016-11-03 15:17:47,256 Parameters: omega_lambda
> > = 0.728
> > yt : [INFO     ] 2016-11-03 15:17:47,256 Parameters: omega_matter
> > = 0.272
> > yt : [INFO     ] 2016-11-03 15:17:47,256 Parameters: hubble_constant
> > = 1.89812815754e-06
> >
> >
> > _______________________________________________
> > yt-users mailing list
> > yt-users at lists.spacepope.org
> > http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
> >
> _______________________________________________
> yt-users mailing list
> yt-users at lists.spacepope.org
> http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.spacepope.org/pipermail/yt-users-spacepope.org/attachments/20161104/0f60e39f/attachment.html>


More information about the yt-users mailing list