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| cannam@127 | 25 <title>FFTW 3.3.5: MPI Plan Creation</title> | 
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| cannam@127 | 71 <body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> | 
| cannam@127 | 72 <a name="MPI-Plan-Creation"></a> | 
| cannam@127 | 73 <div class="header"> | 
| cannam@127 | 74 <p> | 
| cannam@127 | 75 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> | 
| cannam@127 | 76 </div> | 
| cannam@127 | 77 <hr> | 
| cannam@127 | 78 <a name="MPI-Plan-Creation-1"></a> | 
| cannam@127 | 79 <h4 class="subsection">6.12.5 MPI Plan Creation</h4> | 
| cannam@127 | 80 | 
| cannam@127 | 81 <a name="Complex_002ddata-MPI-DFTs"></a> | 
| cannam@127 | 82 <h4 class="subsubheading">Complex-data MPI DFTs</h4> | 
| cannam@127 | 83 | 
| cannam@127 | 84 <p>Plans for complex-data DFTs (see <a href="2d-MPI-example.html#g_t2d-MPI-example">2d MPI example</a>) are created by: | 
| cannam@127 | 85 </p> | 
| cannam@127 | 86 <a name="index-fftw_005fmpi_005fplan_005fdft_005f1d"></a> | 
| cannam@127 | 87 <a name="index-fftw_005fmpi_005fplan_005fdft_005f2d-1"></a> | 
| cannam@127 | 88 <a name="index-fftw_005fmpi_005fplan_005fdft_005f3d"></a> | 
| cannam@127 | 89 <a name="index-fftw_005fmpi_005fplan_005fdft"></a> | 
| cannam@127 | 90 <a name="index-fftw_005fmpi_005fplan_005fmany_005fdft"></a> | 
| cannam@127 | 91 <div class="example"> | 
| cannam@127 | 92 <pre class="example">fftw_plan fftw_mpi_plan_dft_1d(ptrdiff_t n0, fftw_complex *in, fftw_complex *out, | 
| cannam@127 | 93                                MPI_Comm comm, int sign, unsigned flags); | 
| cannam@127 | 94 fftw_plan fftw_mpi_plan_dft_2d(ptrdiff_t n0, ptrdiff_t n1, | 
| cannam@127 | 95                                fftw_complex *in, fftw_complex *out, | 
| cannam@127 | 96                                MPI_Comm comm, int sign, unsigned flags); | 
| cannam@127 | 97 fftw_plan fftw_mpi_plan_dft_3d(ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t n2, | 
| cannam@127 | 98                                fftw_complex *in, fftw_complex *out, | 
| cannam@127 | 99                                MPI_Comm comm, int sign, unsigned flags); | 
| cannam@127 | 100 fftw_plan fftw_mpi_plan_dft(int rnk, const ptrdiff_t *n, | 
| cannam@127 | 101                             fftw_complex *in, fftw_complex *out, | 
| cannam@127 | 102                             MPI_Comm comm, int sign, unsigned flags); | 
| cannam@127 | 103 fftw_plan fftw_mpi_plan_many_dft(int rnk, const ptrdiff_t *n, | 
| cannam@127 | 104                                  ptrdiff_t howmany, ptrdiff_t block, ptrdiff_t tblock, | 
| cannam@127 | 105                                  fftw_complex *in, fftw_complex *out, | 
| cannam@127 | 106                                  MPI_Comm comm, int sign, unsigned flags); | 
| cannam@127 | 107 </pre></div> | 
| cannam@127 | 108 | 
| cannam@127 | 109 <a name="index-MPI-communicator-2"></a> | 
| cannam@127 | 110 <a name="index-collective-function-4"></a> | 
| cannam@127 | 111 <p>These are similar to their serial counterparts (see <a href="Complex-DFTs.html#Complex-DFTs">Complex DFTs</a>) | 
| cannam@127 | 112 in specifying the dimensions, sign, and flags of the transform.  The | 
| cannam@127 | 113 <code>comm</code> argument gives an MPI communicator that specifies the set | 
| cannam@127 | 114 of processes to participate in the transform; plan creation is a | 
| cannam@127 | 115 collective function that must be called for all processes in the | 
| cannam@127 | 116 communicator.  The <code>in</code> and <code>out</code> pointers refer only to a | 
| cannam@127 | 117 portion of the overall transform data (see <a href="MPI-Data-Distribution.html#MPI-Data-Distribution">MPI Data Distribution</a>) | 
| cannam@127 | 118 as specified by the ‘<samp>local_size</samp>’ functions in the previous | 
| cannam@127 | 119 section.  Unless <code>flags</code> contains <code>FFTW_ESTIMATE</code>, these | 
| cannam@127 | 120 arrays are overwritten during plan creation as for the serial | 
| cannam@127 | 121 interface.  For multi-dimensional transforms, any dimensions <code>> | 
| cannam@127 | 122 1</code> are supported; for one-dimensional transforms, only composite | 
| cannam@127 | 123 (non-prime) <code>n0</code> are currently supported (unlike the serial | 
| cannam@127 | 124 FFTW).  Requesting an unsupported transform size will yield a | 
| cannam@127 | 125 <code>NULL</code> plan.  (As in the serial interface, highly composite sizes | 
| cannam@127 | 126 generally yield the best performance.) | 
| cannam@127 | 127 </p> | 
| cannam@127 | 128 <a name="index-advanced-interface-6"></a> | 
| cannam@127 | 129 <a name="index-FFTW_005fMPI_005fDEFAULT_005fBLOCK-2"></a> | 
| cannam@127 | 130 <a name="index-stride-3"></a> | 
| cannam@127 | 131 <p>The advanced-interface <code>fftw_mpi_plan_many_dft</code> additionally | 
| cannam@127 | 132 allows you to specify the block sizes for the first dimension | 
| cannam@127 | 133 (<code>block</code>) of the n<sub>0</sub> × n<sub>1</sub> × n<sub>2</sub> × … × n<sub>d-1</sub> input data and the first dimension | 
| cannam@127 | 134 (<code>tblock</code>) of the n<sub>1</sub> × n<sub>0</sub> × n<sub>2</sub> ×…× n<sub>d-1</sub> transposed data (at intermediate | 
| cannam@127 | 135 steps of the transform, and for the output if | 
| cannam@127 | 136 <code>FFTW_TRANSPOSED_OUT</code> is specified in <code>flags</code>).  These must | 
| cannam@127 | 137 be the same block sizes as were passed to the corresponding | 
| cannam@127 | 138 ‘<samp>local_size</samp>’ function; you can pass <code>FFTW_MPI_DEFAULT_BLOCK</code> | 
| cannam@127 | 139 to use FFTW’s default block size as in the basic interface.  Also, the | 
| cannam@127 | 140 <code>howmany</code> parameter specifies that the transform is of contiguous | 
| cannam@127 | 141 <code>howmany</code>-tuples rather than individual complex numbers; this | 
| cannam@127 | 142 corresponds to the same parameter in the serial advanced interface | 
| cannam@127 | 143 (see <a href="Advanced-Complex-DFTs.html#Advanced-Complex-DFTs">Advanced Complex DFTs</a>) with <code>stride = howmany</code> and | 
| cannam@127 | 144 <code>dist = 1</code>. | 
| cannam@127 | 145 </p> | 
| cannam@127 | 146 <a name="MPI-flags"></a> | 
| cannam@127 | 147 <h4 class="subsubheading">MPI flags</h4> | 
| cannam@127 | 148 | 
| cannam@127 | 149 <p>The <code>flags</code> can be any of those for the serial FFTW | 
| cannam@127 | 150 (see <a href="Planner-Flags.html#Planner-Flags">Planner Flags</a>), and in addition may include one or more of | 
| cannam@127 | 151 the following MPI-specific flags, which improve performance at the | 
| cannam@127 | 152 cost of changing the output or input data formats. | 
| cannam@127 | 153 </p> | 
| cannam@127 | 154 <ul> | 
| cannam@127 | 155 <li> <a name="index-FFTW_005fMPI_005fSCRAMBLED_005fOUT-2"></a> | 
| cannam@127 | 156 <a name="index-FFTW_005fMPI_005fSCRAMBLED_005fIN-2"></a> | 
| cannam@127 | 157 <code>FFTW_MPI_SCRAMBLED_OUT</code>, <code>FFTW_MPI_SCRAMBLED_IN</code>: valid for | 
| cannam@127 | 158 1d transforms only, these flags indicate that the output/input of the | 
| cannam@127 | 159 transform are in an undocumented “scrambled” order.  A forward | 
| cannam@127 | 160 <code>FFTW_MPI_SCRAMBLED_OUT</code> transform can be inverted by a backward | 
| cannam@127 | 161 <code>FFTW_MPI_SCRAMBLED_IN</code> (times the usual 1/<i>N</i> normalization). | 
| cannam@127 | 162 See <a href="One_002ddimensional-distributions.html#One_002ddimensional-distributions">One-dimensional distributions</a>. | 
| cannam@127 | 163 | 
| cannam@127 | 164 </li><li> <a name="index-FFTW_005fMPI_005fTRANSPOSED_005fOUT-2"></a> | 
| cannam@127 | 165 <a name="index-FFTW_005fMPI_005fTRANSPOSED_005fIN-2"></a> | 
| cannam@127 | 166 <code>FFTW_MPI_TRANSPOSED_OUT</code>, <code>FFTW_MPI_TRANSPOSED_IN</code>: valid | 
| cannam@127 | 167 for multidimensional (<code>rnk > 1</code>) transforms only, these flags | 
| cannam@127 | 168 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> transform is | 
| cannam@127 | 169 transposed to n<sub>1</sub> × n<sub>0</sub> × n<sub>2</sub> ×…× n<sub>d-1</sub>.  See <a href="Transposed-distributions.html#Transposed-distributions">Transposed distributions</a>. | 
| cannam@127 | 170 | 
| cannam@127 | 171 </li></ul> | 
| cannam@127 | 172 | 
| cannam@127 | 173 <a name="Real_002ddata-MPI-DFTs"></a> | 
| cannam@127 | 174 <h4 class="subsubheading">Real-data MPI DFTs</h4> | 
| cannam@127 | 175 | 
| cannam@127 | 176 <a name="index-r2c-4"></a> | 
| cannam@127 | 177 <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: | 
| cannam@127 | 178 </p> | 
| cannam@127 | 179 <a name="index-fftw_005fmpi_005fplan_005fdft_005fr2c_005f2d"></a> | 
| cannam@127 | 180 <a name="index-fftw_005fmpi_005fplan_005fdft_005fr2c_005f2d-1"></a> | 
| cannam@127 | 181 <a name="index-fftw_005fmpi_005fplan_005fdft_005fr2c_005f3d"></a> | 
| cannam@127 | 182 <a name="index-fftw_005fmpi_005fplan_005fdft_005fr2c"></a> | 
| cannam@127 | 183 <a name="index-fftw_005fmpi_005fplan_005fdft_005fc2r_005f2d"></a> | 
| cannam@127 | 184 <a name="index-fftw_005fmpi_005fplan_005fdft_005fc2r_005f2d-1"></a> | 
| cannam@127 | 185 <a name="index-fftw_005fmpi_005fplan_005fdft_005fc2r_005f3d"></a> | 
| cannam@127 | 186 <a name="index-fftw_005fmpi_005fplan_005fdft_005fc2r"></a> | 
| cannam@127 | 187 <div class="example"> | 
| cannam@127 | 188 <pre class="example">fftw_plan fftw_mpi_plan_dft_r2c_2d(ptrdiff_t n0, ptrdiff_t n1, | 
| cannam@127 | 189                                    double *in, fftw_complex *out, | 
| cannam@127 | 190                                    MPI_Comm comm, unsigned flags); | 
| cannam@127 | 191 fftw_plan fftw_mpi_plan_dft_r2c_2d(ptrdiff_t n0, ptrdiff_t n1, | 
| cannam@127 | 192                                    double *in, fftw_complex *out, | 
| cannam@127 | 193                                    MPI_Comm comm, unsigned flags); | 
| cannam@127 | 194 fftw_plan fftw_mpi_plan_dft_r2c_3d(ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t n2, | 
| cannam@127 | 195                                    double *in, fftw_complex *out, | 
| cannam@127 | 196                                    MPI_Comm comm, unsigned flags); | 
| cannam@127 | 197 fftw_plan fftw_mpi_plan_dft_r2c(int rnk, const ptrdiff_t *n, | 
| cannam@127 | 198                                 double *in, fftw_complex *out, | 
| cannam@127 | 199                                 MPI_Comm comm, unsigned flags); | 
| cannam@127 | 200 fftw_plan fftw_mpi_plan_dft_c2r_2d(ptrdiff_t n0, ptrdiff_t n1, | 
| cannam@127 | 201                                    fftw_complex *in, double *out, | 
| cannam@127 | 202                                    MPI_Comm comm, unsigned flags); | 
| cannam@127 | 203 fftw_plan fftw_mpi_plan_dft_c2r_2d(ptrdiff_t n0, ptrdiff_t n1, | 
| cannam@127 | 204                                    fftw_complex *in, double *out, | 
| cannam@127 | 205                                    MPI_Comm comm, unsigned flags); | 
| cannam@127 | 206 fftw_plan fftw_mpi_plan_dft_c2r_3d(ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t n2, | 
| cannam@127 | 207                                    fftw_complex *in, double *out, | 
| cannam@127 | 208                                    MPI_Comm comm, unsigned flags); | 
| cannam@127 | 209 fftw_plan fftw_mpi_plan_dft_c2r(int rnk, const ptrdiff_t *n, | 
| cannam@127 | 210                                 fftw_complex *in, double *out, | 
| cannam@127 | 211                                 MPI_Comm comm, unsigned flags); | 
| cannam@127 | 212 </pre></div> | 
| cannam@127 | 213 | 
| cannam@127 | 214 <p>Similar to the serial interface (see <a href="Real_002ddata-DFTs.html#Real_002ddata-DFTs">Real-data DFTs</a>), these | 
| cannam@127 | 215 transform logically n<sub>0</sub> × n<sub>1</sub> × n<sub>2</sub> × … × n<sub>d-1</sub> real data to/from n<sub>0</sub> × n<sub>1</sub> × n<sub>2</sub> × … × (n<sub>d-1</sub>/2 + 1) complex | 
| cannam@127 | 216 data, representing the non-redundant half of the conjugate-symmetry | 
| cannam@127 | 217 output of a real-input DFT (see <a href="Multi_002ddimensional-Transforms.html#Multi_002ddimensional-Transforms">Multi-dimensional Transforms</a>). | 
| cannam@127 | 218 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)] | 
| cannam@127 | 219 array (much like the in-place serial r2c transforms, but here for | 
| cannam@127 | 220 out-of-place transforms as well). Currently, only multi-dimensional | 
| cannam@127 | 221 (<code>rnk > 1</code>) r2c/c2r transforms are supported (requesting a plan | 
| cannam@127 | 222 for <code>rnk = 1</code> will yield <code>NULL</code>).  As explained above | 
| cannam@127 | 223 (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 | 
| cannam@127 | 224 distribution of both the real and complex arrays is given by the | 
| cannam@127 | 225 ‘<samp>local_size</samp>’ function called for the dimensions of the | 
| cannam@127 | 226 <em>complex</em> array.  Similar to the other planning functions, the | 
| cannam@127 | 227 input and output arrays are overwritten when the plan is created | 
| cannam@127 | 228 except in <code>FFTW_ESTIMATE</code> mode. | 
| cannam@127 | 229 </p> | 
| cannam@127 | 230 <p>As for the complex DFTs above, there is an advance interface that | 
| cannam@127 | 231 allows you to manually specify block sizes and to transform contiguous | 
| cannam@127 | 232 <code>howmany</code>-tuples of real/complex numbers: | 
| cannam@127 | 233 </p> | 
| cannam@127 | 234 <a name="index-fftw_005fmpi_005fplan_005fmany_005fdft_005fr2c"></a> | 
| cannam@127 | 235 <a name="index-fftw_005fmpi_005fplan_005fmany_005fdft_005fc2r"></a> | 
| cannam@127 | 236 <div class="example"> | 
| cannam@127 | 237 <pre class="example">fftw_plan fftw_mpi_plan_many_dft_r2c | 
| cannam@127 | 238               (int rnk, const ptrdiff_t *n, ptrdiff_t howmany, | 
| cannam@127 | 239                ptrdiff_t iblock, ptrdiff_t oblock, | 
| cannam@127 | 240                double *in, fftw_complex *out, | 
| cannam@127 | 241                MPI_Comm comm, unsigned flags); | 
| cannam@127 | 242 fftw_plan fftw_mpi_plan_many_dft_c2r | 
| cannam@127 | 243               (int rnk, const ptrdiff_t *n, ptrdiff_t howmany, | 
| cannam@127 | 244                ptrdiff_t iblock, ptrdiff_t oblock, | 
| cannam@127 | 245                fftw_complex *in, double *out, | 
| cannam@127 | 246                MPI_Comm comm, unsigned flags); | 
| cannam@127 | 247 </pre></div> | 
| cannam@127 | 248 | 
| cannam@127 | 249 <a name="MPI-r2r-transforms"></a> | 
| cannam@127 | 250 <h4 class="subsubheading">MPI r2r transforms</h4> | 
| cannam@127 | 251 | 
| cannam@127 | 252 <a name="index-r2r-4"></a> | 
| cannam@127 | 253 <p>There are corresponding plan-creation routines for r2r | 
| cannam@127 | 254 transforms (see <a href="More-DFTs-of-Real-Data.html#More-DFTs-of-Real-Data">More DFTs of Real Data</a>), currently supporting | 
| cannam@127 | 255 multidimensional (<code>rnk > 1</code>) transforms only (<code>rnk = 1</code> will | 
| cannam@127 | 256 yield a <code>NULL</code> plan): | 
| cannam@127 | 257 </p> | 
| cannam@127 | 258 <div class="example"> | 
| cannam@127 | 259 <pre class="example">fftw_plan fftw_mpi_plan_r2r_2d(ptrdiff_t n0, ptrdiff_t n1, | 
| cannam@127 | 260                                double *in, double *out, | 
| cannam@127 | 261                                MPI_Comm comm, | 
| cannam@127 | 262                                fftw_r2r_kind kind0, fftw_r2r_kind kind1, | 
| cannam@127 | 263                                unsigned flags); | 
| cannam@127 | 264 fftw_plan fftw_mpi_plan_r2r_3d(ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t n2, | 
| cannam@127 | 265                                double *in, double *out, | 
| cannam@127 | 266                                MPI_Comm comm, | 
| cannam@127 | 267                                fftw_r2r_kind kind0, fftw_r2r_kind kind1, fftw_r2r_kind kind2, | 
| cannam@127 | 268                                unsigned flags); | 
| cannam@127 | 269 fftw_plan fftw_mpi_plan_r2r(int rnk, const ptrdiff_t *n, | 
| cannam@127 | 270                             double *in, double *out, | 
| cannam@127 | 271                             MPI_Comm comm, const fftw_r2r_kind *kind, | 
| cannam@127 | 272                             unsigned flags); | 
| cannam@127 | 273 fftw_plan fftw_mpi_plan_many_r2r(int rnk, const ptrdiff_t *n, | 
| cannam@127 | 274                                  ptrdiff_t iblock, ptrdiff_t oblock, | 
| cannam@127 | 275                                  double *in, double *out, | 
| cannam@127 | 276                                  MPI_Comm comm, const fftw_r2r_kind *kind, | 
| cannam@127 | 277                                  unsigned flags); | 
| cannam@127 | 278 </pre></div> | 
| cannam@127 | 279 | 
| cannam@127 | 280 <p>The parameters are much the same as for the complex DFTs above, except | 
| cannam@127 | 281 that the arrays are of real numbers (and hence the outputs of the | 
| cannam@127 | 282 ‘<samp>local_size</samp>’ data-distribution functions should be interpreted as | 
| cannam@127 | 283 counts of real rather than complex numbers).  Also, the <code>kind</code> | 
| cannam@127 | 284 parameters specify the r2r kinds along each dimension as for the | 
| cannam@127 | 285 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>. | 
| cannam@127 | 286 </p> | 
| cannam@127 | 287 <a name="MPI-transposition"></a> | 
| cannam@127 | 288 <h4 class="subsubheading">MPI transposition</h4> | 
| cannam@127 | 289 <a name="index-transpose-5"></a> | 
| cannam@127 | 290 | 
| cannam@127 | 291 <p>FFTW also provides routines to plan a transpose of a distributed | 
| cannam@127 | 292 <code>n0</code> by <code>n1</code> array of real numbers, or an array of | 
| cannam@127 | 293 <code>howmany</code>-tuples of real numbers with specified block sizes | 
| cannam@127 | 294 (see <a href="FFTW-MPI-Transposes.html#FFTW-MPI-Transposes">FFTW MPI Transposes</a>): | 
| cannam@127 | 295 </p> | 
| cannam@127 | 296 <a name="index-fftw_005fmpi_005fplan_005ftranspose-1"></a> | 
| cannam@127 | 297 <a name="index-fftw_005fmpi_005fplan_005fmany_005ftranspose-1"></a> | 
| cannam@127 | 298 <div class="example"> | 
| cannam@127 | 299 <pre class="example">fftw_plan fftw_mpi_plan_transpose(ptrdiff_t n0, ptrdiff_t n1, | 
| cannam@127 | 300                                   double *in, double *out, | 
| cannam@127 | 301                                   MPI_Comm comm, unsigned flags); | 
| cannam@127 | 302 fftw_plan fftw_mpi_plan_many_transpose | 
| cannam@127 | 303                 (ptrdiff_t n0, ptrdiff_t n1, ptrdiff_t howmany, | 
| cannam@127 | 304                  ptrdiff_t block0, ptrdiff_t block1, | 
| cannam@127 | 305                  double *in, double *out, MPI_Comm comm, unsigned flags); | 
| cannam@127 | 306 </pre></div> | 
| cannam@127 | 307 | 
| cannam@127 | 308 <a name="index-new_002darray-execution-2"></a> | 
| cannam@127 | 309 <a name="index-fftw_005fmpi_005fexecute_005fr2r-1"></a> | 
| cannam@127 | 310 <p>These plans are used with the <code>fftw_mpi_execute_r2r</code> new-array | 
| cannam@127 | 311 execute function (see <a href="Using-MPI-Plans.html#Using-MPI-Plans">Using MPI Plans</a>), since they count as (rank | 
| cannam@127 | 312 zero) r2r plans from FFTW’s perspective. | 
| cannam@127 | 313 </p> | 
| cannam@127 | 314 <hr> | 
| cannam@127 | 315 <div class="header"> | 
| cannam@127 | 316 <p> | 
| cannam@127 | 317 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> | 
| cannam@127 | 318 </div> | 
| cannam@127 | 319 | 
| cannam@127 | 320 | 
| cannam@127 | 321 | 
| cannam@127 | 322 </body> | 
| cannam@127 | 323 </html> |