furnace/extern/fftw/rdft/rdft2-tensor-max-index.c

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/*
* 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 "rdft/rdft.h"
/* like X(tensor_max_index), but takes into account the special n/2+1
final dimension for the complex output/input of an R2HC/HC2R transform. */
INT X(rdft2_tensor_max_index)(const tensor *sz, rdft_kind k)
{
int i;
INT n = 0;
A(FINITE_RNK(sz->rnk));
for (i = 0; i + 1 < sz->rnk; ++i) {
const iodim *p = sz->dims + i;
n += (p->n - 1) * X(imax)(X(iabs)(p->is), X(iabs)(p->os));
}
if (i < sz->rnk) {
const iodim *p = sz->dims + i;
INT is, os;
X(rdft2_strides)(k, p, &is, &os);
n += X(imax)((p->n - 1) * X(iabs)(is), (p->n/2) * X(iabs)(os));
}
return n;
}