<div dir="ltr">Hi Rebecca,<div><br></div><div>I have to confess it was a _long_ time since I looked into these parts of the code, but you might be able to achieve this simply by defining a group, giving it the initial velocity you want, and then using the constant-acceleration functionality with the value 0.0 (since zero constant acceleration means constant speed).</div><div><br></div><div>And if that fails, it should be possible to fix it without too much effort :-)</div><div><br></div><div>Otherwise, the idea of the user groups is exactly that you should be able to quickly implement a small routine where you do something to an arbitrary group without having to redefine the input mdp options, create a new (incompatible) TPR version, and also having to modify the enum lists.</div><div><br></div><div>Cheers,</div><div><br></div><div>Erik</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Fri, Apr 10, 2020 at 12:55 PM Rebecca Kleemann <<a href="mailto:rkleeman@students.uni-mainz.de">rkleeman@students.uni-mainz.de</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-style:solid;border-left-color:rgb(204,204,204);padding-left:1ex">
<div>
<p>Hi, <br>
</p>
<p>I want to add a group to set atoms to a constant velocity.</p>
<blockquote>
<p><font size="-1" face="Courier New, Courier, monospace">enum<br>
{<br>
egcTC, egcENER, egcACC, egcFREEZE,<br>
egcUser1, egcUser2, egcVCM, egcCompressedX,<br>
egcORFIT, egcQMMM,<br>
egcNR<br>
};</font></p>
<p><font size="-1" face="Courier New, Courier, monospace">const
char *gtypes[egcNR+1] = {<br>
"T-Coupling", "Energy Mon.", "Acceleration", "Freeze",<br>
"User1", "User2", "VCM", "Compressed X", "Or. Res. Fit",
"QMMM", nullptr<br>
};</font><br>
</p>
</blockquote>
<p>Are "User1" and "User2" meant to be used like that and can they
be renamed or should I add a new group and increase the number of
groups?</p>
<p>Greetings,</p>
<p>Rebecca<br>
</p>
</div>
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