[yt-users] Dealing with HOP groups

[Agarwal, Shankar]

Hi Sam,

Here is how I am using it right now...

hp.add_halo_filter(HP.VirialFilter,must_be_virialized=True,
              overdensity_field='ActualOverdensity',
              virial_overdensity=200,
              virial_filters=[['TotalMassMsun','>=','5e11']],
              virial_quantities=['TotalMassMsun','RadiusMpc'])
hp.make_profiles(filename="VirialHaloes.out")

And i get 500.


Do you think it has something to do with the grid spacing (for 512 ^3 grid in 200 Box, it is 390 Kpc)

HaloProfiler may be skipping small halos completely since they are smaller than 390 Kpc.


Shankar


-----Original Message-----
From: yt-users-bounces at lists.spacepope.org on behalf of Sam Skillman
Sent: Sun 2/28/2010 12:34 PM
To: Discussion of the yt analysis package
Subject: Re: [yt-users] Dealing with HOP groups
 
Hi Shankar,

Do you have a line that looks like:
hp.add_halo_filter(HP.VirialFilter,must_be_virialized=True,
                   overdensity_field='ActualOverdensity',
                   virial_overdensity=200,
                   virial_filters=[['TotalMassMsun','>=','1e14']],
                   virial_quantities=['TotalMassMsun','RadiusMpc'])

If so, please post it.  The number of halos > 10^14 Msun is fairly close to
500 in a 200 Mpc box.  If you want the halo profiler to use all halos, set
virial_filters=[['TotalMassMsun','>=','1e14']]  accordingly.

Sam

On Sun, Feb 28, 2010 at 11:08 AM, Agarwal, Shankar <sagarwal at ku.edu> wrote:

> Hi Stephen,
>
> I read
> http://lists.spacepope.org/pipermail/yt-users-spacepope.org/2009-March/000110.html
>
> Do you remember the cosmology parameters for your run: particles, grid,
> box, refinement, AMR ON or OFF ?
>
>
> I have run a 200 Mpc/h box, 512^3 particle, 512^3 grid, AMR-OFF simulation
> and I get about 30,000 halos using HOP. When I try to finding virial halos,
> I get only 500. I may have to increase the grid to 1024^3.
>
> Let me know how you got 40,000 virial halos.
>
> Thanks
> Shankar
> _______________________________________________
> yt-users mailing list
> yt-users at lists.spacepope.org
> http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>



-- 
Samuel W. Skillman
DOE Computational Science Graduate Fellow
Center for Astrophysics and Space Astronomy
University of Colorado at Boulder
samuel.skillman[at]colorado.edu

-------------- next part --------------
A non-text attachment was scrubbed...
Name: winmail.dat
Type: application/ms-tnef
Size: 3871 bytes
Desc: not available
URL: <http://lists.spacepope.org/pipermail/yt-users-spacepope.org/attachments/20100228/b05ca275/attachment-0001.bin>