<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 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 href="mailto:hudan_bazhaoyu@sjtu.edu.cn">hudan_bazhaoyu@sjtu.edu.cn</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 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 align="left" class="gmail_msg">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 href="mailto:hudan_bazhaoyu@163.com" class="gmail_msg" target="_blank">hudan_bazhaoyu@163.com</a><br class="gmail_msg"><br><br>                 <a 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"><br><a href="mailto:yt-users@lists.spacepope.org" class="gmail_msg" target="_blank">yt-users@lists.spacepope.org</a><br class="gmail_msg"><br><a 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"><br></blockquote></div></div>