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			5.3 KiB
		
	
	
	
		
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			110 lines
		
	
	
		
			5.3 KiB
		
	
	
	
		
			HTML
		
	
	
	
	
	
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								<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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								<html>
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								<!-- This manual is for FFTW
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								(version 3.3.10, 10 December 2020).
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								Copyright (C) 2003 Matteo Frigo.
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								Copyright (C) 2003 Massachusetts Institute of Technology.
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								Permission is granted to make and distribute verbatim copies of this
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								manual provided the copyright notice and this permission notice are
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								preserved on all copies.
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								Permission is granted to copy and distribute modified versions of this
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								manual under the conditions for verbatim copying, provided that the
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								entire resulting derived work is distributed under the terms of a
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								permission notice identical to this one.
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								Permission is granted to copy and distribute translations of this manual
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								into another language, under the above conditions for modified versions,
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								except that this permission notice may be stated in a translation
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								approved by the Free Software Foundation. -->
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								<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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								<title>Tutorial (FFTW 3.3.10)</title>
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								<meta name="description" content="Tutorial (FFTW 3.3.10)">
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								<meta name="keywords" content="Tutorial (FFTW 3.3.10)">
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								<link href="index.html" rel="start" title="Top">
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								<link href="Concept-Index.html" rel="index" title="Concept Index">
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								<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
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								<link href="index.html" rel="up" title="Top">
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								<link href="Complex-One_002dDimensional-DFTs.html" rel="next" title="Complex One-Dimensional DFTs">
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								<link href="Introduction.html" rel="prev" title="Introduction">
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								<body lang="en">
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								<span id="Tutorial"></span><div class="header">
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								<p>
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								Next: <a href="Other-Important-Topics.html" accesskey="n" rel="next">Other Important Topics</a>, Previous: <a href="Introduction.html" accesskey="p" rel="prev">Introduction</a>, Up: <a href="index.html" accesskey="u" rel="up">Top</a>   [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html" title="Index" rel="index">Index</a>]</p>
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								</div>
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								<hr>
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								<span id="Tutorial-1"></span><h2 class="chapter">2 Tutorial</h2>
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								<table class="menu" border="0" cellspacing="0">
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								<tr><td align="left" valign="top">• <a href="Complex-One_002dDimensional-DFTs.html" accesskey="1">Complex One-Dimensional DFTs</a></td><td>  </td><td align="left" valign="top">
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								</td></tr>
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								<tr><td align="left" valign="top">• <a href="Complex-Multi_002dDimensional-DFTs.html" accesskey="2">Complex Multi-Dimensional DFTs</a></td><td>  </td><td align="left" valign="top">
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								</td></tr>
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								<tr><td align="left" valign="top">• <a href="One_002dDimensional-DFTs-of-Real-Data.html" accesskey="3">One-Dimensional DFTs of Real Data</a></td><td>  </td><td align="left" valign="top">
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								</td></tr>
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								<tr><td align="left" valign="top">• <a href="Multi_002dDimensional-DFTs-of-Real-Data.html" accesskey="4">Multi-Dimensional DFTs of Real Data</a></td><td>  </td><td align="left" valign="top">
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								</td></tr>
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								<tr><td align="left" valign="top">• <a href="More-DFTs-of-Real-Data.html" accesskey="5">More DFTs of Real Data</a></td><td>  </td><td align="left" valign="top">
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								</td></tr>
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								</table>
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								<p>This chapter describes the basic usage of FFTW, i.e., how to compute
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								<span id="index-basic-interface-1"></span>
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								the Fourier transform of a single array.  This chapter tells the
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								truth, but not the <em>whole</em> truth. Specifically, FFTW implements
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								additional routines and flags that are not documented here, although
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								in many cases we try to indicate where added capabilities exist.  For
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								more complete information, see <a href="FFTW-Reference.html">FFTW Reference</a>.  (Note that you
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								need to compile and install FFTW before you can use it in a program.
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								For the details of the installation, see <a href="Installation-and-Customization.html">Installation and Customization</a>.)
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								</p>
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								<p>We recommend that you read this tutorial in order.<a id="DOCF1" href="#FOOT1"><sup>1</sup></a>  At the least, read the first section (see <a href="Complex-One_002dDimensional-DFTs.html">Complex One-Dimensional DFTs</a>) before reading any of the others, even if your
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								main interest lies in one of the other transform types.
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								</p>
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								<p>Users of FFTW version 2 and earlier may also want to read <a href="Upgrading-from-FFTW-version-2.html">Upgrading from FFTW version 2</a>.
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								</p>
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								<div class="footnote">
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								<hr>
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								<h4 class="footnotes-heading">Footnotes</h4>
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								<h5><a id="FOOT1" href="#DOCF1">(1)</a></h3>
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								<p>You can
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								read the tutorial in bit-reversed order after computing your first
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								transform.</p>
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								</div>
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								</html>
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