Mercurial > hg > sv-dependency-builds

diff src/fftw-3.3.3/doc/html/Guru-Real_002ddata-DFTs.html @ 10:37bf6b4a2645

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Add FFTW3
author Chris Cannam
date Wed, 20 Mar 2013 15:35:50 +0000
parents
children
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/fftw-3.3.3/doc/html/Guru-Real_002ddata-DFTs.html	Wed Mar 20 15:35:50 2013 +0000
@@ -0,0 +1,125 @@
+<html lang="en">
+<head>
+<title>Guru Real-data DFTs - FFTW 3.3.3</title>
+<meta http-equiv="Content-Type" content="text/html">
+<meta name="description" content="FFTW 3.3.3">
+<meta name="generator" content="makeinfo 4.13">
+<link title="Top" rel="start" href="index.html#Top">
+<link rel="up" href="Guru-Interface.html#Guru-Interface" title="Guru Interface">
+<link rel="prev" href="Guru-Complex-DFTs.html#Guru-Complex-DFTs" title="Guru Complex DFTs">
+<link rel="next" href="Guru-Real_002dto_002dreal-Transforms.html#Guru-Real_002dto_002dreal-Transforms" title="Guru Real-to-real Transforms">
+<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage">
+<!--
+This manual is for FFTW
+(version 3.3.3, 25 November 2012).
+
+Copyright (C) 2003 Matteo Frigo.
+
+Copyright (C) 2003 Massachusetts Institute of Technology.
+
+     Permission is granted to make and distribute verbatim copies of
+     this manual provided the copyright notice and this permission
+     notice are preserved on all copies.
+
+     Permission is granted to copy and distribute modified versions of
+     this manual under the conditions for verbatim copying, provided
+     that the entire resulting derived work is distributed under the
+     terms of a permission notice identical to this one.
+
+     Permission is granted to copy and distribute translations of this
+     manual into another language, under the above conditions for
+     modified versions, except that this permission notice may be
+     stated in a translation approved by the Free Software Foundation.
+   -->
+<meta http-equiv="Content-Style-Type" content="text/css">
+<style type="text/css"><!--
+  pre.display { font-family:inherit }
+  pre.format  { font-family:inherit }
+  pre.smalldisplay { font-family:inherit; font-size:smaller }
+  pre.smallformat  { font-family:inherit; font-size:smaller }
+  pre.smallexample { font-size:smaller }
+  pre.smalllisp    { font-size:smaller }
+  span.sc    { font-variant:small-caps }
+  span.roman { font-family:serif; font-weight:normal; } 
+  span.sansserif { font-family:sans-serif; font-weight:normal; } 
+--></style>
+</head>
+<body>
+<div class="node">
+<a name="Guru-Real-data-DFTs"></a>
+<a name="Guru-Real_002ddata-DFTs"></a>
+<p>
+Next:&nbsp;<a rel="next" accesskey="n" href="Guru-Real_002dto_002dreal-Transforms.html#Guru-Real_002dto_002dreal-Transforms">Guru Real-to-real Transforms</a>,
+Previous:&nbsp;<a rel="previous" accesskey="p" href="Guru-Complex-DFTs.html#Guru-Complex-DFTs">Guru Complex DFTs</a>,
+Up:&nbsp;<a rel="up" accesskey="u" href="Guru-Interface.html#Guru-Interface">Guru Interface</a>
+<hr>
+</div>
+
+<h4 class="subsection">4.5.4 Guru Real-data DFTs</h4>
+
+<pre class="example">     fftw_plan fftw_plan_guru_dft_r2c(
+          int rank, const fftw_iodim *dims,
+          int howmany_rank, const fftw_iodim *howmany_dims,
+          double *in, fftw_complex *out,
+          unsigned flags);
+     
+     fftw_plan fftw_plan_guru_split_dft_r2c(
+          int rank, const fftw_iodim *dims,
+          int howmany_rank, const fftw_iodim *howmany_dims,
+          double *in, double *ro, double *io,
+          unsigned flags);
+     
+     fftw_plan fftw_plan_guru_dft_c2r(
+          int rank, const fftw_iodim *dims,
+          int howmany_rank, const fftw_iodim *howmany_dims,
+          fftw_complex *in, double *out,
+          unsigned flags);
+     
+     fftw_plan fftw_plan_guru_split_dft_c2r(
+          int rank, const fftw_iodim *dims,
+          int howmany_rank, const fftw_iodim *howmany_dims,
+          double *ri, double *ii, double *out,
+          unsigned flags);
+</pre>
+   <p><a name="index-fftw_005fplan_005fguru_005fdft_005fr2c-251"></a><a name="index-fftw_005fplan_005fguru_005fsplit_005fdft_005fr2c-252"></a><a name="index-fftw_005fplan_005fguru_005fdft_005fc2r-253"></a><a name="index-fftw_005fplan_005fguru_005fsplit_005fdft_005fc2r-254"></a>
+Plan a real-input (r2c) or real-output (c2r), multi-dimensional DFT with
+transform dimensions given by (<code>rank</code>, <code>dims</code>) over a
+multi-dimensional vector (loop) of dimensions (<code>howmany_rank</code>,
+<code>howmany_dims</code>).  <code>dims</code> and <code>howmany_dims</code> should point
+to <code>fftw_iodim</code> arrays of length <code>rank</code> and
+<code>howmany_rank</code>, respectively.  As for the basic and advanced
+interfaces, an r2c transform is <code>FFTW_FORWARD</code> and a c2r transform
+is <code>FFTW_BACKWARD</code>.
+
+   <p>The <em>last</em> dimension of <code>dims</code> is interpreted specially:
+that dimension of the real array has size <code>dims[rank-1].n</code>, but
+that dimension of the complex array has size <code>dims[rank-1].n/2+1</code>
+(division rounded down).  The strides, on the other hand, are taken to
+be exactly as specified.  It is up to the user to specify the strides
+appropriately for the peculiar dimensions of the data, and we do not
+guarantee that the planner will succeed (return non-<code>NULL</code>) for
+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,
+for an in-place transform, each individual dimension should be able to
+operate in place.) 
+<a name="index-in_002dplace-255"></a>
+
+   <p><code>in</code> and <code>out</code> point to the input and output arrays for r2c
+and c2r transforms, respectively.  For split arrays, <code>ri</code> and
+<code>ii</code> point to the real and imaginary input arrays for a c2r
+transform, and <code>ro</code> and <code>io</code> point to the real and imaginary
+output arrays for an r2c transform.  <code>in</code> and <code>ro</code> or
+<code>ri</code> and <code>out</code> may be the same, indicating an in-place
+transform.   (In-place transforms where <code>in</code> and <code>io</code> or
+<code>ii</code> and <code>out</code> are the same are not currently supported.)
+
+   <p><a name="index-flags-256"></a><code>flags</code> is a bitwise OR (&lsquo;<samp><span class="samp">|</span></samp>&rsquo;) of zero or more planner flags,
+as defined in <a href="Planner-Flags.html#Planner-Flags">Planner Flags</a>.
+
+   <p>In-place transforms of rank greater than 1 are currently only
+supported for interleaved arrays.  For split arrays, the planner will
+return <code>NULL</code>. 
+<a name="index-in_002dplace-257"></a>
+<!-- =========> -->
+
+   </body></html>
+