|
Chris@82
|
1 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
|
|
Chris@82
|
2 <html>
|
|
Chris@82
|
3 <!-- This manual is for FFTW
|
|
Chris@82
|
4 (version 3.3.8, 24 May 2018).
|
|
Chris@82
|
5
|
|
Chris@82
|
6 Copyright (C) 2003 Matteo Frigo.
|
|
Chris@82
|
7
|
|
Chris@82
|
8 Copyright (C) 2003 Massachusetts Institute of Technology.
|
|
Chris@82
|
9
|
|
Chris@82
|
10 Permission is granted to make and distribute verbatim copies of this
|
|
Chris@82
|
11 manual provided the copyright notice and this permission notice are
|
|
Chris@82
|
12 preserved on all copies.
|
|
Chris@82
|
13
|
|
Chris@82
|
14 Permission is granted to copy and distribute modified versions of this
|
|
Chris@82
|
15 manual under the conditions for verbatim copying, provided that the
|
|
Chris@82
|
16 entire resulting derived work is distributed under the terms of a
|
|
Chris@82
|
17 permission notice identical to this one.
|
|
Chris@82
|
18
|
|
Chris@82
|
19 Permission is granted to copy and distribute translations of this manual
|
|
Chris@82
|
20 into another language, under the above conditions for modified versions,
|
|
Chris@82
|
21 except that this permission notice may be stated in a translation
|
|
Chris@82
|
22 approved by the Free Software Foundation. -->
|
|
Chris@82
|
23 <!-- Created by GNU Texinfo 6.3, http://www.gnu.org/software/texinfo/ -->
|
|
Chris@82
|
24 <head>
|
|
Chris@82
|
25 <title>FFTW 3.3.8: MPI Plan Creation</title>
|
|
Chris@82
|
26
|
|
Chris@82
|
27 <meta name="description" content="FFTW 3.3.8: MPI Plan Creation">
|
|
Chris@82
|
28 <meta name="keywords" content="FFTW 3.3.8: MPI Plan Creation">
|
|
Chris@82
|
29 <meta name="resource-type" content="document">
|
|
Chris@82
|
30 <meta name="distribution" content="global">
|
|
Chris@82
|
31 <meta name="Generator" content="makeinfo">
|
|
Chris@82
|
32 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
|
|
Chris@82
|
33 <link href="index.html#Top" rel="start" title="Top">
|
|
Chris@82
|
34 <link href="Concept-Index.html#Concept-Index" rel="index" title="Concept Index">
|
|
Chris@82
|
35 <link href="index.html#SEC_Contents" rel="contents" title="Table of Contents">
|
|
Chris@82
|
36 <link href="FFTW-MPI-Reference.html#FFTW-MPI-Reference" rel="up" title="FFTW MPI Reference">
|
|
Chris@82
|
37 <link href="MPI-Wisdom-Communication.html#MPI-Wisdom-Communication" rel="next" title="MPI Wisdom Communication">
|
|
Chris@82
|
38 <link href="MPI-Data-Distribution-Functions.html#MPI-Data-Distribution-Functions" rel="prev" title="MPI Data Distribution Functions">
|
|
Chris@82
|
39 <style type="text/css">
|
|
Chris@82
|
40 <!--
|
|
Chris@82
|
41 a.summary-letter {text-decoration: none}
|
|
Chris@82
|
42 blockquote.indentedblock {margin-right: 0em}
|
|
Chris@82
|
43 blockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
|
|
Chris@82
|
44 blockquote.smallquotation {font-size: smaller}
|
|
Chris@82
|
45 div.display {margin-left: 3.2em}
|
|
Chris@82
|
46 div.example {margin-left: 3.2em}
|
|
Chris@82
|
47 div.lisp {margin-left: 3.2em}
|
|
Chris@82
|
48 div.smalldisplay {margin-left: 3.2em}
|
|
Chris@82
|
49 div.smallexample {margin-left: 3.2em}
|
|
Chris@82
|
50 div.smalllisp {margin-left: 3.2em}
|
|
Chris@82
|
51 kbd {font-style: oblique}
|
|
Chris@82
|
52 pre.display {font-family: inherit}
|
|
Chris@82
|
53 pre.format {font-family: inherit}
|
|
Chris@82
|
54 pre.menu-comment {font-family: serif}
|
|
Chris@82
|
55 pre.menu-preformatted {font-family: serif}
|
|
Chris@82
|
56 pre.smalldisplay {font-family: inherit; font-size: smaller}
|
|
Chris@82
|
57 pre.smallexample {font-size: smaller}
|
|
Chris@82
|
58 pre.smallformat {font-family: inherit; font-size: smaller}
|
|
Chris@82
|
59 pre.smalllisp {font-size: smaller}
|
|
Chris@82
|
60 span.nolinebreak {white-space: nowrap}
|
|
Chris@82
|
61 span.roman {font-family: initial; font-weight: normal}
|
|
Chris@82
|
62 span.sansserif {font-family: sans-serif; font-weight: normal}
|
|
Chris@82
|
63 ul.no-bullet {list-style: none}
|
|
Chris@82
|
64 -->
|
|
Chris@82
|
65 </style>
|
|
Chris@82
|
66
|
|
Chris@82
|
67
|
|
Chris@82
|
68 </head>
|
|
Chris@82
|
69
|
|
Chris@82
|
70 <body lang="en">
|
|
Chris@82
|
71 <a name="MPI-Plan-Creation"></a>
|
|
Chris@82
|
72 <div class="header">
|
|
Chris@82
|
73 <p>
|
|
Chris@82
|
74 Next: <a href="MPI-Wisdom-Communication.html#MPI-Wisdom-Communication" accesskey="n" rel="next">MPI Wisdom Communication</a>, Previous: <a href="MPI-Data-Distribution-Functions.html#MPI-Data-Distribution-Functions" accesskey="p" rel="prev">MPI Data Distribution Functions</a>, Up: <a href="FFTW-MPI-Reference.html#FFTW-MPI-Reference" accesskey="u" rel="up">FFTW MPI Reference</a> [<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@82
|
75 </div>
|
|
Chris@82
|
76 <hr>
|
|
Chris@82
|
77 <a name="MPI-Plan-Creation-1"></a>
|
|
Chris@82
|
78 <h4 class="subsection">6.12.5 MPI Plan Creation</h4>
|
|
Chris@82
|
79
|
|
Chris@82
|
80 <a name="Complex_002ddata-MPI-DFTs"></a>
|
|
Chris@82
|
81 <h4 class="subsubheading">Complex-data MPI DFTs</h4>
|
|
Chris@82
|
82
|
|
Chris@82
|
83 <p>Plans for complex-data DFTs (see <a href="2d-MPI-example.html#g_t2d-MPI-example">2d MPI example</a>) are created by:
|
|
Chris@82
|
84 </p>
|
|
Chris@82
|
85 <a name="index-fftw_005fmpi_005fplan_005fdft_005f1d"></a>
|
|
Chris@82
|
86 <a name="index-fftw_005fmpi_005fplan_005fdft_005f2d-1"></a>
|
|
Chris@82
|
87 <a name="index-fftw_005fmpi_005fplan_005fdft_005f3d"></a>
|
|
Chris@82
|
88 <a name="index-fftw_005fmpi_005fplan_005fdft"></a>
|
|
Chris@82
|
89 <a name="index-fftw_005fmpi_005fplan_005fmany_005fdft"></a>
|
|
Chris@82
|
90 <div class="example">
|
|
Chris@82
|
91 <pre class="example">fftw_plan fftw_mpi_plan_dft_1d(ptrdiff_t n0, fftw_complex *in, fftw_complex *out,
|
|
Chris@82
|
92 MPI_Comm comm, int sign, unsigned flags);
|
|
Chris@82
|
93 fftw_plan fftw_mpi_plan_dft_2d(ptrdiff_t n0, ptrdiff_t n1,
|
|
Chris@82
|
94 fftw_complex *in, fftw_complex *out,
|
|
Chris@82
|
95 MPI_Comm comm, int sign, unsigned flags);
|
|
Chris@82
|
96 fftw_plan fftw_mpi_plan_dft_3d(ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t n2,
|
|
Chris@82
|
97 fftw_complex *in, fftw_complex *out,
|
|
Chris@82
|
98 MPI_Comm comm, int sign, unsigned flags);
|
|
Chris@82
|
99 fftw_plan fftw_mpi_plan_dft(int rnk, const ptrdiff_t *n,
|
|
Chris@82
|
100 fftw_complex *in, fftw_complex *out,
|
|
Chris@82
|
101 MPI_Comm comm, int sign, unsigned flags);
|
|
Chris@82
|
102 fftw_plan fftw_mpi_plan_many_dft(int rnk, const ptrdiff_t *n,
|
|
Chris@82
|
103 ptrdiff_t howmany, ptrdiff_t block, ptrdiff_t tblock,
|
|
Chris@82
|
104 fftw_complex *in, fftw_complex *out,
|
|
Chris@82
|
105 MPI_Comm comm, int sign, unsigned flags);
|
|
Chris@82
|
106 </pre></div>
|
|
Chris@82
|
107
|
|
Chris@82
|
108 <a name="index-MPI-communicator-2"></a>
|
|
Chris@82
|
109 <a name="index-collective-function-4"></a>
|
|
Chris@82
|
110 <p>These are similar to their serial counterparts (see <a href="Complex-DFTs.html#Complex-DFTs">Complex DFTs</a>)
|
|
Chris@82
|
111 in specifying the dimensions, sign, and flags of the transform. The
|
|
Chris@82
|
112 <code>comm</code> argument gives an MPI communicator that specifies the set
|
|
Chris@82
|
113 of processes to participate in the transform; plan creation is a
|
|
Chris@82
|
114 collective function that must be called for all processes in the
|
|
Chris@82
|
115 communicator. The <code>in</code> and <code>out</code> pointers refer only to a
|
|
Chris@82
|
116 portion of the overall transform data (see <a href="MPI-Data-Distribution.html#MPI-Data-Distribution">MPI Data Distribution</a>)
|
|
Chris@82
|
117 as specified by the ‘<samp>local_size</samp>’ functions in the previous
|
|
Chris@82
|
118 section. Unless <code>flags</code> contains <code>FFTW_ESTIMATE</code>, these
|
|
Chris@82
|
119 arrays are overwritten during plan creation as for the serial
|
|
Chris@82
|
120 interface. For multi-dimensional transforms, any dimensions <code>>
|
|
Chris@82
|
121 1</code> are supported; for one-dimensional transforms, only composite
|
|
Chris@82
|
122 (non-prime) <code>n0</code> are currently supported (unlike the serial
|
|
Chris@82
|
123 FFTW). Requesting an unsupported transform size will yield a
|
|
Chris@82
|
124 <code>NULL</code> plan. (As in the serial interface, highly composite sizes
|
|
Chris@82
|
125 generally yield the best performance.)
|
|
Chris@82
|
126 </p>
|
|
Chris@82
|
127 <a name="index-advanced-interface-6"></a>
|
|
Chris@82
|
128 <a name="index-FFTW_005fMPI_005fDEFAULT_005fBLOCK-2"></a>
|
|
Chris@82
|
129 <a name="index-stride-3"></a>
|
|
Chris@82
|
130 <p>The advanced-interface <code>fftw_mpi_plan_many_dft</code> additionally
|
|
Chris@82
|
131 allows you to specify the block sizes for the first dimension
|
|
Chris@82
|
132 (<code>block</code>) of the n<sub>0</sub> × n<sub>1</sub> × n<sub>2</sub> × … × n<sub>d-1</sub>
|
|
Chris@82
|
133 input data and the first dimension
|
|
Chris@82
|
134 (<code>tblock</code>) of the n<sub>1</sub> × n<sub>0</sub> × n<sub>2</sub> ×…× n<sub>d-1</sub>
|
|
Chris@82
|
135 transposed data (at intermediate
|
|
Chris@82
|
136 steps of the transform, and for the output if
|
|
Chris@82
|
137 <code>FFTW_TRANSPOSED_OUT</code> is specified in <code>flags</code>). These must
|
|
Chris@82
|
138 be the same block sizes as were passed to the corresponding
|
|
Chris@82
|
139 ‘<samp>local_size</samp>’ function; you can pass <code>FFTW_MPI_DEFAULT_BLOCK</code>
|
|
Chris@82
|
140 to use FFTW’s default block size as in the basic interface. Also, the
|
|
Chris@82
|
141 <code>howmany</code> parameter specifies that the transform is of contiguous
|
|
Chris@82
|
142 <code>howmany</code>-tuples rather than individual complex numbers; this
|
|
Chris@82
|
143 corresponds to the same parameter in the serial advanced interface
|
|
Chris@82
|
144 (see <a href="Advanced-Complex-DFTs.html#Advanced-Complex-DFTs">Advanced Complex DFTs</a>) with <code>stride = howmany</code> and
|
|
Chris@82
|
145 <code>dist = 1</code>.
|
|
Chris@82
|
146 </p>
|
|
Chris@82
|
147 <a name="MPI-flags"></a>
|
|
Chris@82
|
148 <h4 class="subsubheading">MPI flags</h4>
|
|
Chris@82
|
149
|
|
Chris@82
|
150 <p>The <code>flags</code> can be any of those for the serial FFTW
|
|
Chris@82
|
151 (see <a href="Planner-Flags.html#Planner-Flags">Planner Flags</a>), and in addition may include one or more of
|
|
Chris@82
|
152 the following MPI-specific flags, which improve performance at the
|
|
Chris@82
|
153 cost of changing the output or input data formats.
|
|
Chris@82
|
154 </p>
|
|
Chris@82
|
155 <ul>
|
|
Chris@82
|
156 <li> <a name="index-FFTW_005fMPI_005fSCRAMBLED_005fOUT-2"></a>
|
|
Chris@82
|
157 <a name="index-FFTW_005fMPI_005fSCRAMBLED_005fIN-2"></a>
|
|
Chris@82
|
158 <code>FFTW_MPI_SCRAMBLED_OUT</code>, <code>FFTW_MPI_SCRAMBLED_IN</code>: valid for
|
|
Chris@82
|
159 1d transforms only, these flags indicate that the output/input of the
|
|
Chris@82
|
160 transform are in an undocumented “scrambled” order. A forward
|
|
Chris@82
|
161 <code>FFTW_MPI_SCRAMBLED_OUT</code> transform can be inverted by a backward
|
|
Chris@82
|
162 <code>FFTW_MPI_SCRAMBLED_IN</code> (times the usual 1/<i>N</i> normalization).
|
|
Chris@82
|
163 See <a href="One_002ddimensional-distributions.html#One_002ddimensional-distributions">One-dimensional distributions</a>.
|
|
Chris@82
|
164
|
|
Chris@82
|
165 </li><li> <a name="index-FFTW_005fMPI_005fTRANSPOSED_005fOUT-2"></a>
|
|
Chris@82
|
166 <a name="index-FFTW_005fMPI_005fTRANSPOSED_005fIN-2"></a>
|
|
Chris@82
|
167 <code>FFTW_MPI_TRANSPOSED_OUT</code>, <code>FFTW_MPI_TRANSPOSED_IN</code>: valid
|
|
Chris@82
|
168 for multidimensional (<code>rnk > 1</code>) transforms only, these flags
|
|
Chris@82
|
169 specify that the output or input of an n<sub>0</sub> × n<sub>1</sub> × n<sub>2</sub> × … × n<sub>d-1</sub>
|
|
Chris@82
|
170 transform is
|
|
Chris@82
|
171 transposed to n<sub>1</sub> × n<sub>0</sub> × n<sub>2</sub> ×…× n<sub>d-1</sub>
|
|
Chris@82
|
172 . See <a href="Transposed-distributions.html#Transposed-distributions">Transposed distributions</a>.
|
|
Chris@82
|
173
|
|
Chris@82
|
174 </li></ul>
|
|
Chris@82
|
175
|
|
Chris@82
|
176 <a name="Real_002ddata-MPI-DFTs"></a>
|
|
Chris@82
|
177 <h4 class="subsubheading">Real-data MPI DFTs</h4>
|
|
Chris@82
|
178
|
|
Chris@82
|
179 <a name="index-r2c-4"></a>
|
|
Chris@82
|
180 <p>Plans for real-input/output (r2c/c2r) DFTs (see <a href="Multi_002ddimensional-MPI-DFTs-of-Real-Data.html#Multi_002ddimensional-MPI-DFTs-of-Real-Data">Multi-dimensional MPI DFTs of Real Data</a>) are created by:
|
|
Chris@82
|
181 </p>
|
|
Chris@82
|
182 <a name="index-fftw_005fmpi_005fplan_005fdft_005fr2c_005f2d"></a>
|
|
Chris@82
|
183 <a name="index-fftw_005fmpi_005fplan_005fdft_005fr2c_005f2d-1"></a>
|
|
Chris@82
|
184 <a name="index-fftw_005fmpi_005fplan_005fdft_005fr2c_005f3d"></a>
|
|
Chris@82
|
185 <a name="index-fftw_005fmpi_005fplan_005fdft_005fr2c"></a>
|
|
Chris@82
|
186 <a name="index-fftw_005fmpi_005fplan_005fdft_005fc2r_005f2d"></a>
|
|
Chris@82
|
187 <a name="index-fftw_005fmpi_005fplan_005fdft_005fc2r_005f2d-1"></a>
|
|
Chris@82
|
188 <a name="index-fftw_005fmpi_005fplan_005fdft_005fc2r_005f3d"></a>
|
|
Chris@82
|
189 <a name="index-fftw_005fmpi_005fplan_005fdft_005fc2r"></a>
|
|
Chris@82
|
190 <div class="example">
|
|
Chris@82
|
191 <pre class="example">fftw_plan fftw_mpi_plan_dft_r2c_2d(ptrdiff_t n0, ptrdiff_t n1,
|
|
Chris@82
|
192 double *in, fftw_complex *out,
|
|
Chris@82
|
193 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
194 fftw_plan fftw_mpi_plan_dft_r2c_2d(ptrdiff_t n0, ptrdiff_t n1,
|
|
Chris@82
|
195 double *in, fftw_complex *out,
|
|
Chris@82
|
196 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
197 fftw_plan fftw_mpi_plan_dft_r2c_3d(ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t n2,
|
|
Chris@82
|
198 double *in, fftw_complex *out,
|
|
Chris@82
|
199 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
200 fftw_plan fftw_mpi_plan_dft_r2c(int rnk, const ptrdiff_t *n,
|
|
Chris@82
|
201 double *in, fftw_complex *out,
|
|
Chris@82
|
202 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
203 fftw_plan fftw_mpi_plan_dft_c2r_2d(ptrdiff_t n0, ptrdiff_t n1,
|
|
Chris@82
|
204 fftw_complex *in, double *out,
|
|
Chris@82
|
205 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
206 fftw_plan fftw_mpi_plan_dft_c2r_2d(ptrdiff_t n0, ptrdiff_t n1,
|
|
Chris@82
|
207 fftw_complex *in, double *out,
|
|
Chris@82
|
208 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
209 fftw_plan fftw_mpi_plan_dft_c2r_3d(ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t n2,
|
|
Chris@82
|
210 fftw_complex *in, double *out,
|
|
Chris@82
|
211 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
212 fftw_plan fftw_mpi_plan_dft_c2r(int rnk, const ptrdiff_t *n,
|
|
Chris@82
|
213 fftw_complex *in, double *out,
|
|
Chris@82
|
214 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
215 </pre></div>
|
|
Chris@82
|
216
|
|
Chris@82
|
217 <p>Similar to the serial interface (see <a href="Real_002ddata-DFTs.html#Real_002ddata-DFTs">Real-data DFTs</a>), these
|
|
Chris@82
|
218 transform logically n<sub>0</sub> × n<sub>1</sub> × n<sub>2</sub> × … × n<sub>d-1</sub>
|
|
Chris@82
|
219 real data to/from n<sub>0</sub> × n<sub>1</sub> × n<sub>2</sub> × … × (n<sub>d-1</sub>/2 + 1)
|
|
Chris@82
|
220 complex
|
|
Chris@82
|
221 data, representing the non-redundant half of the conjugate-symmetry
|
|
Chris@82
|
222 output of a real-input DFT (see <a href="Multi_002ddimensional-Transforms.html#Multi_002ddimensional-Transforms">Multi-dimensional Transforms</a>).
|
|
Chris@82
|
223 However, the real array must be stored within a padded n<sub>0</sub> × n<sub>1</sub> × n<sub>2</sub> × … × [2 (n<sub>d-1</sub>/2 + 1)]
|
|
Chris@82
|
224
|
|
Chris@82
|
225 array (much like the in-place serial r2c transforms, but here for
|
|
Chris@82
|
226 out-of-place transforms as well). Currently, only multi-dimensional
|
|
Chris@82
|
227 (<code>rnk > 1</code>) r2c/c2r transforms are supported (requesting a plan
|
|
Chris@82
|
228 for <code>rnk = 1</code> will yield <code>NULL</code>). As explained above
|
|
Chris@82
|
229 (see <a href="Multi_002ddimensional-MPI-DFTs-of-Real-Data.html#Multi_002ddimensional-MPI-DFTs-of-Real-Data">Multi-dimensional MPI DFTs of Real Data</a>), the data
|
|
Chris@82
|
230 distribution of both the real and complex arrays is given by the
|
|
Chris@82
|
231 ‘<samp>local_size</samp>’ function called for the dimensions of the
|
|
Chris@82
|
232 <em>complex</em> array. Similar to the other planning functions, the
|
|
Chris@82
|
233 input and output arrays are overwritten when the plan is created
|
|
Chris@82
|
234 except in <code>FFTW_ESTIMATE</code> mode.
|
|
Chris@82
|
235 </p>
|
|
Chris@82
|
236 <p>As for the complex DFTs above, there is an advance interface that
|
|
Chris@82
|
237 allows you to manually specify block sizes and to transform contiguous
|
|
Chris@82
|
238 <code>howmany</code>-tuples of real/complex numbers:
|
|
Chris@82
|
239 </p>
|
|
Chris@82
|
240 <a name="index-fftw_005fmpi_005fplan_005fmany_005fdft_005fr2c"></a>
|
|
Chris@82
|
241 <a name="index-fftw_005fmpi_005fplan_005fmany_005fdft_005fc2r"></a>
|
|
Chris@82
|
242 <div class="example">
|
|
Chris@82
|
243 <pre class="example">fftw_plan fftw_mpi_plan_many_dft_r2c
|
|
Chris@82
|
244 (int rnk, const ptrdiff_t *n, ptrdiff_t howmany,
|
|
Chris@82
|
245 ptrdiff_t iblock, ptrdiff_t oblock,
|
|
Chris@82
|
246 double *in, fftw_complex *out,
|
|
Chris@82
|
247 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
248 fftw_plan fftw_mpi_plan_many_dft_c2r
|
|
Chris@82
|
249 (int rnk, const ptrdiff_t *n, ptrdiff_t howmany,
|
|
Chris@82
|
250 ptrdiff_t iblock, ptrdiff_t oblock,
|
|
Chris@82
|
251 fftw_complex *in, double *out,
|
|
Chris@82
|
252 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
253 </pre></div>
|
|
Chris@82
|
254
|
|
Chris@82
|
255 <a name="MPI-r2r-transforms"></a>
|
|
Chris@82
|
256 <h4 class="subsubheading">MPI r2r transforms</h4>
|
|
Chris@82
|
257
|
|
Chris@82
|
258 <a name="index-r2r-4"></a>
|
|
Chris@82
|
259 <p>There are corresponding plan-creation routines for r2r
|
|
Chris@82
|
260 transforms (see <a href="More-DFTs-of-Real-Data.html#More-DFTs-of-Real-Data">More DFTs of Real Data</a>), currently supporting
|
|
Chris@82
|
261 multidimensional (<code>rnk > 1</code>) transforms only (<code>rnk = 1</code> will
|
|
Chris@82
|
262 yield a <code>NULL</code> plan):
|
|
Chris@82
|
263 </p>
|
|
Chris@82
|
264 <div class="example">
|
|
Chris@82
|
265 <pre class="example">fftw_plan fftw_mpi_plan_r2r_2d(ptrdiff_t n0, ptrdiff_t n1,
|
|
Chris@82
|
266 double *in, double *out,
|
|
Chris@82
|
267 MPI_Comm comm,
|
|
Chris@82
|
268 fftw_r2r_kind kind0, fftw_r2r_kind kind1,
|
|
Chris@82
|
269 unsigned flags);
|
|
Chris@82
|
270 fftw_plan fftw_mpi_plan_r2r_3d(ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t n2,
|
|
Chris@82
|
271 double *in, double *out,
|
|
Chris@82
|
272 MPI_Comm comm,
|
|
Chris@82
|
273 fftw_r2r_kind kind0, fftw_r2r_kind kind1, fftw_r2r_kind kind2,
|
|
Chris@82
|
274 unsigned flags);
|
|
Chris@82
|
275 fftw_plan fftw_mpi_plan_r2r(int rnk, const ptrdiff_t *n,
|
|
Chris@82
|
276 double *in, double *out,
|
|
Chris@82
|
277 MPI_Comm comm, const fftw_r2r_kind *kind,
|
|
Chris@82
|
278 unsigned flags);
|
|
Chris@82
|
279 fftw_plan fftw_mpi_plan_many_r2r(int rnk, const ptrdiff_t *n,
|
|
Chris@82
|
280 ptrdiff_t iblock, ptrdiff_t oblock,
|
|
Chris@82
|
281 double *in, double *out,
|
|
Chris@82
|
282 MPI_Comm comm, const fftw_r2r_kind *kind,
|
|
Chris@82
|
283 unsigned flags);
|
|
Chris@82
|
284 </pre></div>
|
|
Chris@82
|
285
|
|
Chris@82
|
286 <p>The parameters are much the same as for the complex DFTs above, except
|
|
Chris@82
|
287 that the arrays are of real numbers (and hence the outputs of the
|
|
Chris@82
|
288 ‘<samp>local_size</samp>’ data-distribution functions should be interpreted as
|
|
Chris@82
|
289 counts of real rather than complex numbers). Also, the <code>kind</code>
|
|
Chris@82
|
290 parameters specify the r2r kinds along each dimension as for the
|
|
Chris@82
|
291 serial interface (see <a href="Real_002dto_002dReal-Transform-Kinds.html#Real_002dto_002dReal-Transform-Kinds">Real-to-Real Transform Kinds</a>). See <a href="Other-Multi_002ddimensional-Real_002ddata-MPI-Transforms.html#Other-Multi_002ddimensional-Real_002ddata-MPI-Transforms">Other Multi-dimensional Real-data MPI Transforms</a>.
|
|
Chris@82
|
292 </p>
|
|
Chris@82
|
293 <a name="MPI-transposition"></a>
|
|
Chris@82
|
294 <h4 class="subsubheading">MPI transposition</h4>
|
|
Chris@82
|
295 <a name="index-transpose-5"></a>
|
|
Chris@82
|
296
|
|
Chris@82
|
297 <p>FFTW also provides routines to plan a transpose of a distributed
|
|
Chris@82
|
298 <code>n0</code> by <code>n1</code> array of real numbers, or an array of
|
|
Chris@82
|
299 <code>howmany</code>-tuples of real numbers with specified block sizes
|
|
Chris@82
|
300 (see <a href="FFTW-MPI-Transposes.html#FFTW-MPI-Transposes">FFTW MPI Transposes</a>):
|
|
Chris@82
|
301 </p>
|
|
Chris@82
|
302 <a name="index-fftw_005fmpi_005fplan_005ftranspose-1"></a>
|
|
Chris@82
|
303 <a name="index-fftw_005fmpi_005fplan_005fmany_005ftranspose-1"></a>
|
|
Chris@82
|
304 <div class="example">
|
|
Chris@82
|
305 <pre class="example">fftw_plan fftw_mpi_plan_transpose(ptrdiff_t n0, ptrdiff_t n1,
|
|
Chris@82
|
306 double *in, double *out,
|
|
Chris@82
|
307 MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
308 fftw_plan fftw_mpi_plan_many_transpose
|
|
Chris@82
|
309 (ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t howmany,
|
|
Chris@82
|
310 ptrdiff_t block0, ptrdiff_t block1,
|
|
Chris@82
|
311 double *in, double *out, MPI_Comm comm, unsigned flags);
|
|
Chris@82
|
312 </pre></div>
|
|
Chris@82
|
313
|
|
Chris@82
|
314 <a name="index-new_002darray-execution-2"></a>
|
|
Chris@82
|
315 <a name="index-fftw_005fmpi_005fexecute_005fr2r-1"></a>
|
|
Chris@82
|
316 <p>These plans are used with the <code>fftw_mpi_execute_r2r</code> new-array
|
|
Chris@82
|
317 execute function (see <a href="Using-MPI-Plans.html#Using-MPI-Plans">Using MPI Plans</a>), since they count as (rank
|
|
Chris@82
|
318 zero) r2r plans from FFTW’s perspective.
|
|
Chris@82
|
319 </p>
|
|
Chris@82
|
320 <hr>
|
|
Chris@82
|
321 <div class="header">
|
|
Chris@82
|
322 <p>
|
|
Chris@82
|
323 Next: <a href="MPI-Wisdom-Communication.html#MPI-Wisdom-Communication" accesskey="n" rel="next">MPI Wisdom Communication</a>, Previous: <a href="MPI-Data-Distribution-Functions.html#MPI-Data-Distribution-Functions" accesskey="p" rel="prev">MPI Data Distribution Functions</a>, Up: <a href="FFTW-MPI-Reference.html#FFTW-MPI-Reference" accesskey="u" rel="up">FFTW MPI Reference</a> [<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@82
|
324 </div>
|
|
Chris@82
|
325
|
|
Chris@82
|
326
|
|
Chris@82
|
327
|
|
Chris@82
|
328 </body>
|
|
Chris@82
|
329 </html>
|
