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<p>Hi,</p>
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<p>CALL setfft1(n,iff1,iff2,iff3,a(1,je1),fft,keigen)</p>
<p>does not mean that only a(1,je1) is passed. a(1,je1) indicates the position<br>
</p>
<p>of the first element of the vector inside setfft1, and the vector is constructed</p>
<p>along the first dimension of a, i.e, a(1:nmat,je1).<br>
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<p><br>
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<p>F. Tran<br>
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<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> Wien <wien-bounces@zeus.theochem.tuwien.ac.at> on behalf of Marcus Ekholm <marcus.ekholm@liu.se><br>
<b>Sent:</b> Wednesday, October 30, 2019 2:15 PM<br>
<b>To:</b> Wien@zeus.theochem.tuwien.ac.at<br>
<b>Subject:</b> [Wien] fourier coefficients in lapw2</font>
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Hi!</div>
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I have a question on how lapw2 calculates the charge density in the interstitial region.
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Inside fourir.F (line 294 in version 19.1) we call setfft1 as:<br>
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CALL setfft1(n,iff1,iff2,iff3,a(1,je1),fft,keigen)<br>
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where a(1,je1) is a single number.<br>
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But the subroutine setfft1 expects A to be an array of a different size:<br>
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<span>!_REAL REAL*8 A(nmat)<br>
</span><span>!_COMPLEX COMPLEX*16 A(nmat)</span></div>
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and inside setfft1 we then loop over (some of) the elements in A, from 1 to n, to set the fft array.<br>
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Where do the elements A(2:n) in settfft1 come from? And in fourir.F why is only a(1, ...) passed to setfft1, why not a(2,...), etc ?</div>
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Best regards,<br>
Marcus<br>
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