widely known free FFT library.

Dependents:   Peach_AudioChannelDividerAndCompensator

Revision:
0:d7215946c769
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/fftpack.h	Sun Oct 11 07:20:35 2015 +0000
@@ -0,0 +1,64 @@
+/*
+ *  This file is part of libfftpack.
+ *
+ *  libfftpack 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.
+ *
+ *  libfftpack 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 libfftpack; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+/*
+ *  libfftpack is being developed at the Max-Planck-Institut fuer Astrophysik
+ *  and financially supported by the Deutsches Zentrum fuer Luft- und Raumfahrt
+ *  (DLR).
+ */
+
+/*
+  fftpack.h : function declarations for fftpack.c
+  Algorithmically based on Fortran-77 FFTPACK by Paul N. Swarztrauber
+  (Version 4, 1985).
+
+  Pekka Janhunen 23.2.1995
+
+  (reformatted by joerg arndt)
+
+  reformatted and slightly enhanced by Martin Reinecke (2004)
+ */
+
+#ifndef PLANCK_FFTPACK_H
+#define PLANCK_FFTPACK_H
+
+#include "c_utils.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*! forward complex transform */
+void cfftf(size_t N, FLOAT complex_data[], FLOAT wrk[]);
+/*! backward complex transform */
+void cfftb(size_t N, FLOAT complex_data[], FLOAT wrk[]);
+/*! initializer for complex transforms */
+void cffti(size_t N, FLOAT wrk[]);
+
+/*! forward real transform */
+void rfftf(size_t N, FLOAT data[], FLOAT wrk[]);
+/*! backward real transform */
+void rfftb(size_t N, FLOAT data[], FLOAT wrk[]);
+/*! initializer for real transforms */
+void rffti(size_t N, FLOAT wrk[]);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif