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authorscuri <scuri>2008-10-17 06:10:15 +0000
committerscuri <scuri>2008-10-17 06:10:15 +0000
commit5a422aba704c375a307a902bafe658342e209906 (patch)
tree5005011e086bb863d8fb587ad3319bbec59b2447 /src/fftw3/rdft/rdft2-inplace-strides.c
First commit - moving from LuaForge to SourceForge
Diffstat (limited to 'src/fftw3/rdft/rdft2-inplace-strides.c')
-rw-r--r--src/fftw3/rdft/rdft2-inplace-strides.c61
1 files changed, 61 insertions, 0 deletions
diff --git a/src/fftw3/rdft/rdft2-inplace-strides.c b/src/fftw3/rdft/rdft2-inplace-strides.c
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+++ b/src/fftw3/rdft/rdft2-inplace-strides.c
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2003 Matteo Frigo
+ * Copyright (c) 2003 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+/* $Id: rdft2-inplace-strides.c,v 1.1 2008/10/17 06:11:29 scuri Exp $ */
+
+#include "rdft.h"
+
+/* Check if the vecsz/sz strides are consistent with the problem
+ being in-place for vecsz.dim[vdim], or for all dimensions
+ if vdim == RNK_MINFTY. We can't just use tensor_inplace_strides
+ because rdft transforms have the unfortunate property of
+ differing input and output sizes. This routine is not
+ exhaustive; we only return 1 for the most common case. */
+int X(rdft2_inplace_strides)(const problem_rdft2 *p, int vdim)
+{
+ int N, Nc;
+ int is, os;
+ int i;
+
+ for (i = 0; i + 1 < p->sz->rnk; ++i)
+ if (p->sz->dims[i].is != p->sz->dims[i].os)
+ return 0;
+
+ if (!FINITE_RNK(p->vecsz->rnk) || p->vecsz->rnk == 0)
+ return 1;
+ if (!FINITE_RNK(vdim)) { /* check all vector dimensions */
+ for (vdim = 0; vdim < p->vecsz->rnk; ++vdim)
+ if (!X(rdft2_inplace_strides)(p, vdim))
+ return 0;
+ return 1;
+ }
+
+ A(vdim < p->vecsz->rnk);
+ if (p->sz->rnk == 0)
+ return(p->vecsz->dims[vdim].is == p->vecsz->dims[vdim].os);
+
+ N = X(tensor_sz)(p->sz);
+ Nc = (N / p->sz->dims[p->sz->rnk-1].n) *
+ (p->sz->dims[p->sz->rnk-1].n/2 + 1);
+ X(rdft2_strides)(p->kind, p->sz->dims + p->sz->rnk - 1, &is, &os);
+ return(p->vecsz->dims[vdim].is == p->vecsz->dims[vdim].os
+ && X(iabs)(p->vecsz->dims[vdim].os)
+ >= X(imax)(Nc * X(iabs)(os), N * X(iabs)(is)));
+}