Hi Junhwan, The answer to both your questions is yes. To plot the density of particles, I'd suggest using the 'particle_density' field, this performs a could in cell interpolation of the particle positions onto a mesh. Its definition starts on line 987 of $YT_HG/yt/utilities/universal_fields.py. Right now there is only a particle density field, if you'd like to visualize other particle properties (like the particle velocities), I would start by looking at the particle density field and then write a new derived field based on the CICDeposit_3 call it uses. You can always add new fields to the top of scripts or alternatively place definitions in a my_plugins.py file that can live in a .yt folder in your home directory. The comoving units can be accessed following this pattern: 'kpc' - kiloparsec in physical units (kpc) 'kpccm' - comoving kiloparsec (kpc / (1+z)) 'kpchcm' - comoving kiloparsec / h (h^-1 kpc / (1+z) ) There are similarly defined units for all of the length units. Unfortunately this isn't documented at the moment and I've opened an issue to do so for the next release. There is also an open issue regarding the way these units are displayed on plot axes labels. This will hopefully be more straightforward in future releases as we are planning to completely refactor the way we handle units. Cheers, Nathan On Apr 22, 2013, at 2:22 PM, Jun-Hwan Choi <jhchoi@pa.uky.edu> wrote:

Hi yt user,

I have run a DM only cosmological simulation. And, I would like to make usual Projection/Slice plots for DM properties (density/ velocity). Is there any way yt compute the dark matter properties and make Projection/Slice plots.

In addition, when I make a Projection/Slice plots for inner ## kpc, it turns out the length is a physical unit. Is there any yt commend set width of plots as comoving length scale? The comoving length scale could be useful when I make time series Projection/Slice plots for a given region.

Thank you in advance, Junhwan

-- -------------------------------------------------------------- Jun-Hwan Choi, Ph.D. Department of Physics and Astronomy, University of Kentucky Tel: (859) 897-6737 Fax: (859) 323-2846 Email: jhchoi@pa.uky.edu URL: http://www.pa.uky.edu/~jhchoi -------------------------------------------------------------- _______________________________________________ yt-users mailing list yt-users@lists.spacepope.org http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org