Message: 1
Date: Mon, 23 May 2016 22:43:09 +0200
From: Io Odderskov <io.odderskov@gmail.com>
To: yt-users@lists.spacepope.org
Subject: [yt-users] HaloMassFunction
Message-ID:
        <CAC0EgOA-tpD5-0nZY9Ssyyh94zhRcXm1vYM6suyOzkucgOAjqg@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"

Dear Yt-users.

I have just started used Yt, which I find to be very useful. However, I am
having trouble converting the units of the output of the
HaloMassFcn-function to match other data sets.

I have tried comparing the Tinker 2008 fitting function produced by
HaloMassFcn to the halo mass function from the Halo Finder Comparison
Project (https://arxiv.org/pdf/1104.0949v1.pdf) and to a halo catalogue
from the DEUS consortium (http://www.deus-consortium.org/deuvo/#download).
In these cases, the halo masses are given in Msun/h, and the cumulative
halo number density in h^3/Mpc^3. According to the Yt-documentation, the
masses output by the HaloMassFcn-function should be in Msun, and the number
densities in 1/Mpc^3. To convert to Msun/h and h^3/Mpc^3, I multiply the
masses by h, and divide the number densities with h^3. In the attached
figure, this corresponds to the line labelled "Tinker2008 - masses
multiplied by h", which does not match the other data sets very well. If I
instead divide the masses by h, I get the line labelled Tinker2008 - masses
divided by h", which looks much better. But I really can't see how to
justify this conversion.

I hope you can help me figure out what I'm doing wrong :-)
Thanks in advance!

Best regards, Io.

script: http://paste.yt-project.org/show/6530/
image http://imgur.com/otWW3QJ

version:

  Version = 3.2.3
  Changeset = bdea84d95099 (stable) @

P.S. When I tried to do "yt upload_image", I got a 404 error. Perhaps imgur
changed their API?
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Message: 2
Date: Mon, 23 May 2016 15:51:20 -0500
From: Nathan Goldbaum <nathan12343@gmail.com>
To: Discussion of the yt analysis package
        <yt-users@lists.spacepope.org>
Subject: Re: [yt-users] HaloMassFunction
Message-ID:
        <CAJXewOn9Eq5f6j_xdJJ-du6it1g4aaAOMiBiz=0-4sifsupk2w@mail.gmail.com>
Content-Type: text/plain; charset="utf-8"

On Mon, May 23, 2016 at 3:43 PM, Io Odderskov <io.odderskov@gmail.com>
wrote:

> Dear Yt-users.
>
> I have just started used Yt, which I find to be very useful. However, I am
> having trouble converting the units of the output of the
> HaloMassFcn-function to match other data sets.
>
> I have tried comparing the Tinker 2008 fitting function produced by
> HaloMassFcn to the halo mass function from the Halo Finder Comparison
> Project (https://arxiv.org/pdf/1104.0949v1.pdf) and to a halo catalogue
> from the DEUS consortium (http://www.deus-consortium.org/deuvo/#download).
> In these cases, the halo masses are given in Msun/h, and the cumulative
> halo number density in h^3/Mpc^3. According to the Yt-documentation, the
> masses output by the HaloMassFcn-function should be in Msun, and the number
> densities in 1/Mpc^3. To convert to Msun/h and h^3/Mpc^3, I multiply the
> masses by h, and divide the number densities with h^3. In the attached
> figure, this corresponds to the line labelled "Tinker2008 - masses
> multiplied by h", which does not match the other data sets very well. If I
> instead divide the masses by h, I get the line labelled Tinker2008 - masses
> divided by h", which looks much better. But I really can't see how to
> justify this conversion.
>

To convert to Msun/h, you're trying to multiply by h? I don't think that's
right --- dividing by h is the correct thing to do.


>
> I hope you can help me figure out what I'm doing wrong :-)
> Thanks in advance!
>
> Best regards, Io.
>
> script: http://paste.yt-project.org/show/6530/
> image http://imgur.com/otWW3QJ
>
> version:
>
>   Version = 3.2.3
>   Changeset = bdea84d95099 (stable) @
>
> P.S. When I tried to do "yt upload_image", I got a 404 error. Perhaps
> imgur changed their API?
>

Yeah, imgur changed their API. This is fixed in the development branch of
yt but hasn't been backported to the stable branch. Perhaps we should do a
3.2.4 release given than 3.3 is taking a bit longer than anticipated to
release.


>
> _______________________________________________
> yt-users mailing list
> yt-users@lists.spacepope.org
> http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org
>
>
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