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Hi Nathan,<br>
<br>
Thank you for your kind reply!<br>
<br>
Yes, I have noticed this part, but there is always some mistakes.<br>
<br>
In my Gadget data, ('PartType0', 'ElectronAbundance') is not a
initial field, so I derived it by manumotive.<br>
<br>
Firstly, I set it equal to 1.15, and checked it is normal:<br>
-------------------------------------------------------------------------------------------------------------------------------------------<br>
>
@derived_field(name=("PartType0","ElectronAbundance"),particle_type=True,
force_override=True)<br>
> def _ElectronAbundance(field,data):<br>
return 1.15<br>
<br>
> print(ad['PartType0','ElectronAbundance'])<br>
1.15 dimensionless<br>
-------------------------------------------------------------------------------------------------------------------------------------------<br>
<br>
Then the corresponding fields:<br>
-------------------------------------------------------------------------------------------------------------------------------------------<br>
>
print(ad['PartType0','InternalEnergy'].in_units('km**2/s**2')[8000])<br>
193516.9375 km**2/s**2<br>
> print(ad['gas','kT'][8000])<br>
1.609844329629573 keV<br>
-------------------------------------------------------------------------------------------------------------------------------------------<br>
<br>
I don't think the value of kT is right, so I made a test:<br>
-------------------------------------------------------------------------------------------------------------------------------------------
<br>
>
@derived_field(name=("PartType0","ElectronAbundance"),particle_type=True,
force_override=True)<br>
> def _ElectronAbundance(field,data):<br>
return 0<br>
<br>
> print(ad['PartType0','ElectronAbundance'])<br>
0.0 dimensionless<br>
<br>
>
print(ad['PartType0','InternalEnergy'].in_units('km**2/s**2')[8000])<br>
193516.9375 km**2/s**2<br>
> print(ad['gas','kT'][8000])<br>
1.609844329629573 keV<br>
-------------------------------------------------------------------------------------------------------------------------------------------<br>
<br>
To my amazement, I got a same value of kT, though I changed the
("PartType0","ElectronAbundance").<br>
I'm confused about it. Is there any points I didn't realize?<br>
<br>
Thank you again!<br>
<br>
Regard,<br>
Dan<br>
<br>
<br>
<br>
<div class="moz-cite-prefix">On 01/02/2017 10:50 PM, Nathan Goldbaum
wrote:<br>
</div>
<blockquote
cite="mid:CAJXewOkhCWNd6-+qza7bLDeLuu2QBt5j4pATet5crN8Xd3BLHg@mail.gmail.com"
type="cite">
<div>Hi Dan,</div>
<div><br>
</div>
<div>This particular field is defined specifically for Gadget data
in the Gadget frontend:</div>
<div><br>
</div>
<div><a moz-do-not-send="true"
href="https://bitbucket.org/yt_analysis/yt/src/09f0ef297d7068078a021fc8290d9e3519baf82d/yt/frontends/gadget/fields.py?at=yt&fileviewer=file-view-default#fields.py-72">https://bitbucket.org/yt_analysis/yt/src/09f0ef297d7068078a021fc8290d9e3519baf82d/yt/frontends/gadget/fields.py?at=yt&fileviewer=file-view-default#fields.py-72</a><br>
</div>
<div><br>
</div>
<div>Nathan</div>
<div><br>
</div>
<div><br>
<div class="gmail_quote">
<div>On Mon, Jan 2, 2017 at 6:33 AM hudan_bazhaoyu <<a
moz-do-not-send="true"
href="mailto:hudan_bazhaoyu@sjtu.edu.cn"><a class="moz-txt-link-abbreviated" href="mailto:hudan_bazhaoyu@sjtu.edu.cn">hudan_bazhaoyu@sjtu.edu.cn</a></a>>
wrote:<br>
</div>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex"><br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<br>
<div bgcolor="#FFFFFF" text="#000000" class="gmail_msg"><br>
<br>
Dear yt:<br class="gmail_msg">
<br>
<br>
<br class="gmail_msg">
<br>
<br>
I have one simple question, but it bothers me these days.<br
class="gmail_msg">
<br>
<br>
<br class="gmail_msg">
<br>
<br>
I used the yt to analysis the "hdf5" files, which
generated by<br>
<br>
Gadget-2. These files have basic fields, like:
("PartType0", "*"),<br>
<br>
("PartType1", "*") and ("all", "*"). Then I want to plot
the density<br>
<br>
map and temperature map, it seems need some derived
fields, like:<br>
<br>
("gas", "density") and ("gas", "temperature").<br
class="gmail_msg">
<br>
<br>
<br class="gmail_msg">
<br>
<br>
I'm curious about how the ("gas","temperature") was
derived, so I<br>
<br>
browsed a lots of documents on the Web, but found nothing.
Please<br>
<br>
see <br class="gmail_msg">
<br>
<br>
<a moz-do-not-send="true"
class="m_-8894632913533027461moz-txt-link-freetext
gmail_msg"
href="http://yt-project.org/doc/reference/field_list.html?highlight=field%20list"
target="_blank">http://yt-project.org/doc/reference/field_list.html?highlight=field%20list</a><br
class="gmail_msg">
<br>
<br>
About the field of ('gas','temperature'), there is "No
source<br>
<br>
available" in "Field Source"!<br class="gmail_msg">
<br>
<br>
<br class="gmail_msg">
<br>
<br>
In my data, the field ("PartType0","InternalEnergy") is
provided by<br>
<br>
me, and I think the temperature should calculated by
Internal Energy<br>
<br>
"E" with the function: k*T = (Gamma -1)*µ*mp*E, where k =
1.38E-16<br>
<br>
erg/K is Boltzmann constant, Gamma = 5/3 for adiabat
particles, μ =<br>
<br>
0.6 is the corresponding mean molecular weight, and mp =
1.67E-24 g<br>
<br>
is proton mass. But this result is about half of the value
of<br>
<br>
("gas","temperature"). <br class="gmail_msg">
<br>
<br>
So what you may know is why, which one is right? I need
your help!<br class="gmail_msg">
<br>
<br>
<br class="gmail_msg">
<br>
<br>
Thank you a lot, and happy new year!<br class="gmail_msg">
<br>
<br>
<br class="gmail_msg">
<br>
<br>
Regard,<br class="gmail_msg">
<br>
<br>
Dan<br class="gmail_msg">
<br>
<br>
<br class="gmail_msg">
<br>
<br>
<br class="gmail_msg">
<br>
<br>
--<br class="gmail_msg">
<br>
<br>
Dan Hu<br class="gmail_msg">
<br>
<br>
=======================================<br
class="gmail_msg">
<br>
<br>
<div class="gmail_msg" align="left">Department of Physics,
Shanghai Jiao Tong<br>
<br>
University <br class="gmail_msg">
<br>
<br>
800 Dongchuan Road, Minhang, Shanghai 200240, PRC</div>
<br>
<br>
E-mail : <a moz-do-not-send="true"
href="mailto:hudan_bazhaoyu@163.com" class="gmail_msg"
target="_blank">hudan_bazhaoyu@163.com</a><br
class="gmail_msg">
<br>
<br>
<a moz-do-not-send="true"
href="mailto:hudan_bazhaoyu@sjtu.edu.cn"
class="gmail_msg" target="_blank">hudan_bazhaoyu@sjtu.edu.cn</a><br
class="gmail_msg">
<br>
<br>
=======================================<br>
<br>
</div>
<br>
<br>
<br>
<br>
_______________________________________________<br
class="gmail_msg">
<br>
yt-users mailing list<br class="gmail_msg">
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class="gmail_msg" target="_blank">yt-users@lists.spacepope.org</a><br
class="gmail_msg">
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href="http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org"
rel="noreferrer" class="gmail_msg" target="_blank">http://lists.spacepope.org/listinfo.cgi/yt-users-spacepope.org</a><br
class="gmail_msg">
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</blockquote>
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