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<blockquote type="cite"
cite="mid:b1d96b9670f82777d4801847a7d21711@onera.fr">
<p class="p1"><span class="s1">Parallelization info</span></p>
<p class="p1"><span class="s1"><span class="Apple-converted-space">
</span>--------------------</span></p>
<p class="p1"><span class="s1"><span class="Apple-converted-space">
</span>sticks: <span class="Apple-converted-space"> </span>dense<span
class="Apple-converted-space"> </span>smooth <span
class="Apple-converted-space"> </span>PW <span
class="Apple-converted-space"> </span>G-vecs:<span
class="Apple-converted-space"> </span>dense <span
class="Apple-converted-space"> </span>smooth<span
class="Apple-converted-space"> </span>PW</span></p>
<p class="p1"><span class="s1"><span class="Apple-converted-space">
</span>Min <span class="Apple-converted-space"> </span>287
<span class="Apple-converted-space"> </span>287 <span
class="Apple-converted-space"> </span>81<span
class="Apple-converted-space"> </span>90079<span
class="Apple-converted-space"> </span>90079 <span
class="Apple-converted-space"> </span>13189</span></p>
<p class="p1"><span class="s1"><span class="Apple-converted-space">
</span>Max <span class="Apple-converted-space"> </span>288
<span class="Apple-converted-space"> </span>288 <span
class="Apple-converted-space"> </span>82<span
class="Apple-converted-space"> </span>90130<span
class="Apple-converted-space"> </span>90130 <span
class="Apple-converted-space"> </span>13206</span></p>
<p class="p1"><span class="s1"><span class="Apple-converted-space">
</span>Sum<span class="Apple-converted-space"> </span>2587<span
class="Apple-converted-space"> </span>2587<span
class="Apple-converted-space"> </span>733 <span
class="Apple-converted-space"> </span>810915 <span
class="Apple-converted-space"> </span>810915<span
class="Apple-converted-space"> </span>118781</span></p>
</blockquote>
<p><br>
</p>
<p>Hello Lorenzo,</p>
<p>the G-vecs are the plane waves, the 3x3 table gives the maximum
and minimum number per CPU and the total number for the charge
density grid (ecutrho), the "smooth" (4xcutwfc) grid, and the
plane-wave (ecutwfc) grid.</p>
<p>The sticks, are the subdivisions of the plane waves over which
the parallelization occurs, i.e. the charge is subdivided in 2587
sticks and every CPU inside a pool gets 287 or 288 to do Fourier
transforms (they used to be called planes, I guess it now depends
if you are using "pencil decomposition" or not)</p>
<blockquote type="cite"
cite="mid:b1d96b9670f82777d4801847a7d21711@onera.fr">
<p>Second, when printing the energies per k-point, a number of G
vectors is given as if it were the number of planewaves ( e.g. "<span
class="s1">k = 0.0833 0.1443 0.0000 (101603</span><span
class="s2"> PWs</span><span class="s1">) <span
class="Apple-converted-space"> </span>bands (ev):" ). What
does this number actually refer to?</span></p>
</blockquote>
<p>It is in fact the number of plane waves used to expand the
wvafunction at that k-point.</p>
<p>The condition to include a plane wave is that (G+k)^2 <
ecutwfc/ħ, which defines a sphere in reciprocal space, with G
being a multiple of the reciprocal axis vectors and k is smaller
than any G. So the number varies with the k-point. Then, in order
to do FFT, all he G from all the spheres are combined and padded
with extra point to make a parallelogram. <br>
</p>
<p>You take a parallelogram of twice the side in order to fit
|psi|^2, and if a larger ecutrho has been defined this will
determine a third grid with |G|^2 < ecutrho/ħ<br>
</p>
<p>hth<br>
</p>
<blockquote type="cite"
cite="mid:b1d96b9670f82777d4801847a7d21711@onera.fr">
<p><span class="s1">Last question: how all these sets are related
to the values of ecutwfc and ecutrho ? <br>
</span></p>
</blockquote>
<p>should be explained above.<br>
</p>
<p><br>
</p>
<blockquote type="cite"
cite="mid:b1d96b9670f82777d4801847a7d21711@onera.fr">
<p><span class="s1">Many thanks! </span></p>
<p><br>
</p>
<div id="signature">-- <br>
<div class="pre"
style="margin: 0; padding: 0; font-family: monospace">Dr.
Lorenzo Sponza<br>
<br>
Chargé de Recherche au CNRS<br>
Université Paris-Saclay, ONERA, CNRS Laboratoire d'étude des
microstructures (LEM)<br>
29 Avenue de la division Leclerc, 92322 Châtillon<br>
Tel: +33146734464<br>
<br>
ETSF Research Team Leader <br>
European Theoretical Spectroscopy Facility<br>
17 Sart-Tilman B-4000 Liège, Belgium</div>
</div>
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</blockquote>
<div class="moz-signature">-- <br>
<small>Dr. Lorenzo Paulatto<br>
IdR @ IMPMC - CNRS UMR 7590 & Sorbonne Université<br>
phone: +33 (0)1 442 79822 / skype: paulatz<br>
<a href="http://people.impmc.fr/lpaulatto/"
class="moz-txt-link-freetext">http://people.impmc.fr/lpaulatto/</a>
- <a href="https://anharmonic.github.io/"
class="moz-txt-link-freetext">https://anharmonic.github.io/</a><br>
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