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Hello, <br>
<br>
Is there a way to continue minimizing after reaching machine
precision? Emtol and the number of iterations are sufficient to
continue.<br>
I am assuming that reaching machine precision means that the
gradient of change from one iteration to another has become so
small that further minimization will not improve the structure. Is
this correct? If so is it possible to change the cut-off point for
this gradient? <br>
<br>
Thank you in advance, have a nice day,<br>
Abdullah<br>
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The machine precision is the limit where the computer can't add a
small number (e.g. the gradient) to a larger number (e.g. the
coordinates). You could try using double precision, where your
computer uses twice the number of bits to store the floating point
numbers. I wouldn't bother doing that though, because the energy
minimization is normally just used to releave structural strain from
your system so that your md simulation won't crash due to enormous
forces.<br>
<br>
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-----------------------------------------------
Erik Marklund, PhD student
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596, 75124 Uppsala, Sweden
phone: +46 18 471 4537 fax: +46 18 511 755
<a class="moz-txt-link-abbreviated" href="mailto:erikm@xray.bmc.uu.se">erikm@xray.bmc.uu.se</a> <a class="moz-txt-link-freetext" href="http://folding.bmc.uu.se/">http://folding.bmc.uu.se/</a>
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