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Update build for AUDIO_COMPONENT_FIX
author Chris Cannam
date Wed, 30 Oct 2019 12:40:34 +0000
parents 2cd0e3b3e1fd
children
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Chris@42 1 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
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Chris@42 3 <!-- This manual is for FFTW
Chris@42 4 (version 3.3.5, 30 July 2016).
Chris@42 5
Chris@42 6 Copyright (C) 2003 Matteo Frigo.
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Chris@42 8 Copyright (C) 2003 Massachusetts Institute of Technology.
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Chris@42 24 <head>
Chris@42 25 <title>FFTW 3.3.5: Guru Real-data DFTs</title>
Chris@42 26
Chris@42 27 <meta name="description" content="FFTW 3.3.5: Guru Real-data DFTs">
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Chris@42 35 <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
Chris@42 36 <link href="Guru-Interface.html#Guru-Interface" rel="up" title="Guru Interface">
Chris@42 37 <link href="Guru-Real_002dto_002dreal-Transforms.html#Guru-Real_002dto_002dreal-Transforms" rel="next" title="Guru Real-to-real Transforms">
Chris@42 38 <link href="Guru-Complex-DFTs.html#Guru-Complex-DFTs" rel="prev" title="Guru Complex DFTs">
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Chris@42 69 </head>
Chris@42 70
Chris@42 71 <body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">
Chris@42 72 <a name="Guru-Real_002ddata-DFTs"></a>
Chris@42 73 <div class="header">
Chris@42 74 <p>
Chris@42 75 Next: <a href="Guru-Real_002dto_002dreal-Transforms.html#Guru-Real_002dto_002dreal-Transforms" accesskey="n" rel="next">Guru Real-to-real Transforms</a>, Previous: <a href="Guru-Complex-DFTs.html#Guru-Complex-DFTs" accesskey="p" rel="prev">Guru Complex DFTs</a>, Up: <a href="Guru-Interface.html#Guru-Interface" accesskey="u" rel="up">Guru Interface</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
Chris@42 76 </div>
Chris@42 77 <hr>
Chris@42 78 <a name="Guru-Real_002ddata-DFTs-1"></a>
Chris@42 79 <h4 class="subsection">4.5.4 Guru Real-data DFTs</h4>
Chris@42 80
Chris@42 81 <div class="example">
Chris@42 82 <pre class="example">fftw_plan fftw_plan_guru_dft_r2c(
Chris@42 83 int rank, const fftw_iodim *dims,
Chris@42 84 int howmany_rank, const fftw_iodim *howmany_dims,
Chris@42 85 double *in, fftw_complex *out,
Chris@42 86 unsigned flags);
Chris@42 87
Chris@42 88 fftw_plan fftw_plan_guru_split_dft_r2c(
Chris@42 89 int rank, const fftw_iodim *dims,
Chris@42 90 int howmany_rank, const fftw_iodim *howmany_dims,
Chris@42 91 double *in, double *ro, double *io,
Chris@42 92 unsigned flags);
Chris@42 93
Chris@42 94 fftw_plan fftw_plan_guru_dft_c2r(
Chris@42 95 int rank, const fftw_iodim *dims,
Chris@42 96 int howmany_rank, const fftw_iodim *howmany_dims,
Chris@42 97 fftw_complex *in, double *out,
Chris@42 98 unsigned flags);
Chris@42 99
Chris@42 100 fftw_plan fftw_plan_guru_split_dft_c2r(
Chris@42 101 int rank, const fftw_iodim *dims,
Chris@42 102 int howmany_rank, const fftw_iodim *howmany_dims,
Chris@42 103 double *ri, double *ii, double *out,
Chris@42 104 unsigned flags);
Chris@42 105 </pre></div>
Chris@42 106 <a name="index-fftw_005fplan_005fguru_005fdft_005fr2c"></a>
Chris@42 107 <a name="index-fftw_005fplan_005fguru_005fsplit_005fdft_005fr2c"></a>
Chris@42 108 <a name="index-fftw_005fplan_005fguru_005fdft_005fc2r"></a>
Chris@42 109 <a name="index-fftw_005fplan_005fguru_005fsplit_005fdft_005fc2r"></a>
Chris@42 110
Chris@42 111 <p>Plan a real-input (r2c) or real-output (c2r), multi-dimensional DFT with
Chris@42 112 transform dimensions given by (<code>rank</code>, <code>dims</code>) over a
Chris@42 113 multi-dimensional vector (loop) of dimensions (<code>howmany_rank</code>,
Chris@42 114 <code>howmany_dims</code>). <code>dims</code> and <code>howmany_dims</code> should point
Chris@42 115 to <code>fftw_iodim</code> arrays of length <code>rank</code> and
Chris@42 116 <code>howmany_rank</code>, respectively. As for the basic and advanced
Chris@42 117 interfaces, an r2c transform is <code>FFTW_FORWARD</code> and a c2r transform
Chris@42 118 is <code>FFTW_BACKWARD</code>.
Chris@42 119 </p>
Chris@42 120 <p>The <em>last</em> dimension of <code>dims</code> is interpreted specially:
Chris@42 121 that dimension of the real array has size <code>dims[rank-1].n</code>, but
Chris@42 122 that dimension of the complex array has size <code>dims[rank-1].n/2+1</code>
Chris@42 123 (division rounded down). The strides, on the other hand, are taken to
Chris@42 124 be exactly as specified. It is up to the user to specify the strides
Chris@42 125 appropriately for the peculiar dimensions of the data, and we do not
Chris@42 126 guarantee that the planner will succeed (return non-<code>NULL</code>) for
Chris@42 127 any dimensions other than those described in <a href="Real_002ddata-DFT-Array-Format.html#Real_002ddata-DFT-Array-Format">Real-data DFT Array Format</a> and generalized in <a href="Advanced-Real_002ddata-DFTs.html#Advanced-Real_002ddata-DFTs">Advanced Real-data DFTs</a>. (That is,
Chris@42 128 for an in-place transform, each individual dimension should be able to
Chris@42 129 operate in place.)
Chris@42 130 <a name="index-in_002dplace-6"></a>
Chris@42 131 </p>
Chris@42 132
Chris@42 133 <p><code>in</code> and <code>out</code> point to the input and output arrays for r2c
Chris@42 134 and c2r transforms, respectively. For split arrays, <code>ri</code> and
Chris@42 135 <code>ii</code> point to the real and imaginary input arrays for a c2r
Chris@42 136 transform, and <code>ro</code> and <code>io</code> point to the real and imaginary
Chris@42 137 output arrays for an r2c transform. <code>in</code> and <code>ro</code> or
Chris@42 138 <code>ri</code> and <code>out</code> may be the same, indicating an in-place
Chris@42 139 transform. (In-place transforms where <code>in</code> and <code>io</code> or
Chris@42 140 <code>ii</code> and <code>out</code> are the same are not currently supported.)
Chris@42 141 </p>
Chris@42 142 <a name="index-flags-6"></a>
Chris@42 143 <p><code>flags</code> is a bitwise OR (&lsquo;<samp>|</samp>&rsquo;) of zero or more planner flags,
Chris@42 144 as defined in <a href="Planner-Flags.html#Planner-Flags">Planner Flags</a>.
Chris@42 145 </p>
Chris@42 146 <p>In-place transforms of rank greater than 1 are currently only
Chris@42 147 supported for interleaved arrays. For split arrays, the planner will
Chris@42 148 return <code>NULL</code>.
Chris@42 149 <a name="index-in_002dplace-7"></a>
Chris@42 150 </p>
Chris@42 151 <hr>
Chris@42 152 <div class="header">
Chris@42 153 <p>
Chris@42 154 Next: <a href="Guru-Real_002dto_002dreal-Transforms.html#Guru-Real_002dto_002dreal-Transforms" accesskey="n" rel="next">Guru Real-to-real Transforms</a>, Previous: <a href="Guru-Complex-DFTs.html#Guru-Complex-DFTs" accesskey="p" rel="prev">Guru Complex DFTs</a>, Up: <a href="Guru-Interface.html#Guru-Interface" accesskey="u" rel="up">Guru Interface</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p>
Chris@42 155 </div>
Chris@42 156
Chris@42 157
Chris@42 158
Chris@42 159 </body>
Chris@42 160 </html>