File: pickdim.c

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fftw3 3.3.8-2
 `12345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455565758596061626364656667686970717273747576777879808182` ``````/* * Copyright (c) 2003, 2007-14 Matteo Frigo * Copyright (c) 2003, 2007-14 Massachusetts Institute of Technology * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA * */ #include "kernel/ifftw.h" /* Given a solver which_dim, a vector sz, and whether or not the transform is out-of-place, return the actual dimension index that it corresponds to. The basic idea here is that we return the which_dim'th valid dimension, starting from the end if which_dim < 0. */ static int really_pickdim(int which_dim, const tensor *sz, int oop, int *dp) { int i; int count_ok = 0; if (which_dim > 0) { for (i = 0; i < sz->rnk; ++i) { if (oop || sz->dims[i].is == sz->dims[i].os) if (++count_ok == which_dim) { *dp = i; return 1; } } } else if (which_dim < 0) { for (i = sz->rnk - 1; i >= 0; --i) { if (oop || sz->dims[i].is == sz->dims[i].os) if (++count_ok == -which_dim) { *dp = i; return 1; } } } else { /* zero: pick the middle, if valid */ i = (sz->rnk - 1) / 2; if (i >= 0 && (oop || sz->dims[i].is == sz->dims[i].os)) { *dp = i; return 1; } } return 0; } /* Like really_pickdim, but only returns 1 if no previous "buddy" which_dim in the buddies list would give the same dim. */ int X(pickdim)(int which_dim, const int *buddies, size_t nbuddies, const tensor *sz, int oop, int *dp) { size_t i; int d1; if (!really_pickdim(which_dim, sz, oop, dp)) return 0; /* check whether some buddy solver would produce the same dim. If so, consider this solver unapplicable and let the buddy take care of it. The smallest-indexed buddy is applicable. */ for (i = 0; i < nbuddies; ++i) { if (buddies[i] == which_dim) break; /* found self */ if (really_pickdim(buddies[i], sz, oop, &d1) && *dp == d1) return 0; /* found equivalent buddy */ } return 1; } ``````