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<p>Hi Hesam,</p>
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<p>I've not looked in detail at this paper, but my guess is that you're trying to do some convolution sums. (How many?)</p>
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<p>One option is just to do them. For n points, the cost for each</p>
<p>is O(n).</p>
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<p>Another option (perhaps), is to map all your data onto a uniform</p>
<p>grid and use an FFT-based convolution (provided your method</p>
<p>can be written this way, as I've seen in at least one paper on the</p>
<p>topic). Here, a parallel FFT might be of value (but there might be</p>
<p>other ways as well).</p>
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<p>hth,</p>
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<p>Paul</p>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Nek5000-users <nek5000-users-bounces@lists.mcs.anl.gov> on behalf of nek5000-users@lists.mcs.anl.gov <nek5000-users@lists.mcs.anl.gov><br>
<b>Sent:</b> Friday, October 27, 2017 2:34:02 PM<br>
<b>To:</b> nek5000-users@lists.mcs.anl.gov<br>
<b>Subject:</b> [Nek5000-users] wavelet decomposition</font>
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<div dir="ltr"><span style="font-size:12.8px">Dear all,</span>
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<div style="font-size:12.8px">I would like to perform a wavelet decomposition on my DNS data of stratified turbulence generated using Nek5000. The details of the decomposition to extract coherent vorticies is explained in this paper:</div>
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<div style="font-size:12.8px"><span style="font-size:13px;font-family:Arial,sans-serif">Farge, M., Schneider, K., Pellegrino, G., Wray, A. A., & Rogallo, R. S. (2003). Coherent vortex extraction in three-dimensional homogeneous turbulence: Comparison between
CVS-wavelet and POD-Fourier decompositions. </span><i style="font-size:13px;font-family:Arial,sans-serif">Physics of Fluids</i><span style="font-size:13px;font-family:Arial,sans-serif">, </span><i style="font-size:13px;font-family:Arial,sans-serif">15</i><span style="font-size:13px;font-family:Arial,sans-serif">(10),
2886-2896.</span><br>
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<div style="font-size:12.8px">I am wondering if anyone in our community has had any experience with integrating the wavelet analysis with Nek5000 in the post-processing mode? </div>
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<div style="font-size:12.8px">If not, would you suggest performing such a decomposition in the VisIt Python Interface using a python package like PyWavelets for example? </div>
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<div style="font-size:12.8px">Thanks a lot for the help,</div>
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<div style="font-size:12.8px">Regards,</div>
<div style="font-size:12.8px">Hesam</div>
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