Hey Desika,<div><br></div><div>You&#39;re right, you need to use all_data:</div><div><br></div>import yt<br><div>ds = yt.load(&quot;your_dataset&quot;)</div>ad = ds.all_data()<div>print ad[&quot;PartType0&quot;, &quot;Coordinates&quot;]</div>
<div><br></div><div>In general all yt data sources will print out the flattened data contained in the source when you query them like a dictionary using an unambiguous string field name or (&#39;field_type&#39;, &#39;field name&#39;)<span></span> tuple.</div>
<div><br></div><div>Nathan<br><div><br>On Thursday, May 22, 2014, Desika Narayanan &lt;<a href="mailto:dnarayan@haverford.edu">dnarayan@haverford.edu</a>&gt; wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">Hi yt,<div><br></div><div>I have a pretty simple question that I ought to know the answer to -  how do I extract the actual values in the field_list or derived_field_list of a ds?</div><div><br></div><div>For example, I have a field: <span style="font-family:Monaco;font-size:11px">(&#39;PartType0&#39;, &#39;Coordinates&#39;),</span></div>


<div><span style="font-family:Monaco;font-size:11px"><br></span></div><div>but printing something like pf[(&#39;PartType0&#39;,&#39;Coordinates&#39;)] doesn&#39;t return the list of particle type 0 coordinates (or anything for that matter).  Do I have to access this through a pf.all_data() command somehow?  </div>


<div><span style="font-family:Monaco;font-size:11px"><br></span></div><div><span style="font-family:Monaco;font-size:11px">Thanks</span></div><div><span style="font-family:Monaco;font-size:11px">-desika</span></div><div>

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