[yt-users] Gadget: Isolated galaxy visualization

[Romain Teyssier]

What if you add a small value to the image and plot it ?
Anyway, could you add the jmages tonthe collaborative document ?

Romain 

> Le 16 nov. 2013 à 03:15, "Keita Todoroki" <keitee at physics.unlv.edu> a écrit :
> 
> Hi all,
> 
> Thank you for your helpful suggestions, Ji-hoon!
> 
> I was able to have all the images to be centered by the center-of-mass
> trick. (For Gadget, it seems we need to specify the field name, which is
> ["deposit","Gas_density"]. Otherwise, the code assumes ["gas","Density"]
> to be read, which doesn't exist for our case. Also, we need to set
> use_cells=False in order for it to work.
> 
> I am now trying to change the background color by set_under(), but it
> turned out that PlotCollection in yt doesn't have it - which means
> p.set_under() obviously doesn't do the job. What would be the best way to
> integrate that function into this script?
> http://www.physics.unlv.edu/~keitee/gadget_agora.py
> 
> Also, is this coloring the background automatically done for AMR codes?
> 
> 
> -Keita
> 
> 
> 
> 
>> Hi Keita,
>> 
>> Thank you so much for sharing the figure.
>> 
>> (1) As for shifting field of views as the disk moves, one could re-center
>> the image at centers-of-mass of the inner 20 kpc-radius sphere.  You may
>> try something like this:
>> 
>> - my_sphere = pf.h.sphere([0.5, 0.5, 0.5], 20.0/pf["kpc"])
>> - center = my_sphere.quantities["CenterOfMass"](use_cells=True,
>> use_particles=True)
>> - p=pc.add_projection("Sigma", ax, center=center, figure=fig,
>> axes=axes[ax][0], use_colorbar=False)
>> 
>> (2) As for the white background (I guess this is what you meant?), you may
>> try to employ set_under() to replace white pixels with the color at the
>> colorbar's lower limit.
>> http://matplotlib.org/examples/pylab_examples/contourf_demo.html
>> 
>> (3) I understand that:  the ways to improve the smoothing in Gadget images
>> is being actively investigated now (for example, see below).  It would be
>> great if Matt or anybody could say what Keita could do to test the new
>> features with Gadget datasets.
>> https://bitbucket.org/yt_analysis/yt-3.0/pull-request/122/fixing-smoothing-to-rather-than-normalize/diff
>> 
>> Best regards,
>> Ji-hoon
>> 
>> 
>> 
>> 
>>> On Nov 15, 2013, at 12:48 PM, Keita Todoroki wrote:
>>> 
>>> Hi,
>>> 
>>> I managed to visualize gadget's isolated galaxy sims, and I'm wondering
>>> if
>>> I can improve the resolution of the image, especially the background,
>>> somehow.
>>> The image and the script can be found below:
>>> 
>>> http://www.physics.unlv.edu/~keitee/isolated_low-res.png
>>> http://www.physics.unlv.edu/~keitee/gadget_agora.py
>>> 
>>> 
>>> Also, the disk moves a bit as time progresses (as you can see on the
>>> right-most column), and I'm wondering if yt can adjust that shift as
>>> well.
>>> 
>>> 
>>> -Keita
>> 
>> ---------------------------------------------------------------
>> Ji-hoon Kim
>> Postdoctoral Scholar in Astrophysics
>> www.jihoonkim.org
>> me at jihoonkim.org / 1(650)714-2879
>> ---------------------------------------------------------------
>