1 files changed, 57 insertions, 0 deletions
diff --git a/src/fftw3/dft/rader-omega.c b/src/fftw3/dft/rader-omega.c
new file mode 100644
index 0000000..7fd86b9
--- /dev/null
+++ b/src/fftw3/dft/rader-omega.c
@@ -0,0 +1,57 @@
+/*
+ * 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
+ *
+ */
+
+#include "dft.h"
+
+static rader_tl *omegas = 0;
+
+R *X(dft_rader_mkomega)(plan *p_, int n, int ginv)
+{
+     plan_dft *p = (plan_dft *) p_;
+     R *omega;
+     int i, gpower;
+     trigreal scale;
+
+     if ((omega = X(rader_tl_find)(n, n, ginv, omegas)))
+	  return omega;
+
+     omega = (R *)MALLOC(sizeof(R) * (n - 1) * 2, TWIDDLES);
+
+     scale = n - 1.0; /* normalization for convolution */
+
+     for (i = 0, gpower = 1; i < n-1; ++i, gpower = MULMOD(gpower, ginv, n)) {
+	  omega[2*i] = X(cos2pi)(gpower, n) / scale;
+	  omega[2*i+1] = FFT_SIGN * X(sin2pi)(gpower, n) / scale;
+     }
+     A(gpower == 1);
+
+     AWAKE(p_, 1);
+     p->apply(p_, omega, omega + 1, omega, omega + 1);
+     AWAKE(p_, 0);
+
+     X(rader_tl_insert)(n, n, ginv, omega, &omegas);
+     return omega;
+}
+
+void X(dft_rader_free_omega)(R **omega)
+{
+     X(rader_tl_delete)(*omega, &omegas);
+     *omega = 0;
+}