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<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">How should I read a trajectory file (big-endian binary
file containing mixed types) in Python?</p>
<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">I know that the file has this format:</p>
<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">Header:</p>
<pre class="default prettyprint prettyprinted" style="margin: 0px 0px 1em; padding: 5px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: 13px; line-height: inherit; font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace, sans-serif; vertical-align: baseline; width: auto; max-height: 600px; overflow: auto; background-color: rgb(239, 240, 241); display: block; color: rgb(57, 51, 24); word-wrap: normal;"><code style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: 13px; line-height: inherit; font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace, sans-serif; vertical-align: baseline; background-color: rgb(239, 240, 241); white-space: inherit;"><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">dynamics duration </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
number of spins </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
tmax </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span></code></pre>
<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">Data (one line per spin per update):</p>
<pre class="default prettyprint prettyprinted" style="margin: 0px 0px 1em; padding: 5px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: 13px; line-height: inherit; font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace, sans-serif; vertical-align: baseline; width: auto; max-height: 600px; overflow: auto; background-color: rgb(239, 240, 241); display: block; color: rgb(57, 51, 24); word-wrap: normal;"><code style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: 13px; line-height: inherit; font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace, sans-serif; vertical-align: baseline; background-color: rgb(239, 240, 241); white-space: inherit;"><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">time </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
spin index </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">int</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
spin x </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
spin y </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
spin z </span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">double</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">)</span></code></pre>
<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">(double refers to a signed double-precision 8-byte
floating point number. int refers to a signed, 32bit (4 byte)
integer.)</p>
<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">I am currently trying:</p>
<pre class="default prettyprint prettyprinted" style="margin: 0px 0px 1em; padding: 5px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: 13px; line-height: inherit; font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace, sans-serif; vertical-align: baseline; width: auto; max-height: 600px; overflow: auto; background-color: rgb(239, 240, 241); display: block; color: rgb(57, 51, 24); word-wrap: normal;"><code style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: 13px; line-height: inherit; font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace, sans-serif; vertical-align: baseline; background-color: rgb(239, 240, 241); white-space: inherit;"><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">for</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> i </span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">in</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> range</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="lit" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(125, 39, 39);">15</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">):</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">
</span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">print</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> </span><span class="kwd" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(16, 16, 148);">struct</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">.</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">unpack</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="str" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(125, 39, 39);">'>f'</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">,</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);"> file</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">.</span><span class="pln" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">read</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">(</span><span class="lit" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(125, 39, 39);">4</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">))[</span><span class="lit" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(125, 39, 39);">0</span><span class="pun" style="margin: 0px; padding: 0px; border: 0px; font-style: inherit; font-variant: inherit; font-weight: inherit; font-stretch: inherit; font-size: inherit; line-height: inherit; font-family: inherit; vertical-align: baseline; color: rgb(48, 51, 54);">]</span></code></pre>
<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">But the data I read out does not make sense...</p>
<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">How should I do instead?</p>
<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">Best,</p>
<p style="margin: 0px 0px 1em; padding: 0px; border: 0px;
font-style: inherit; font-variant: inherit; font-weight:
inherit; font-stretch: inherit; font-size: inherit; line-height:
inherit; font-family: inherit; vertical-align: baseline; clear:
both;">Sidsel<br>
</p>
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