include/gsl/gsl_fft_halfcomplex.h

0001 /* fft/gsl_fft_halfcomplex.h
0002  *
0003  * Copyright (C) 1996, 1997, 1998, 1999, 2000, 2007 Brian Gough
0004  *
0005  * This program is free software; you can redistribute it and/or modify
0006  * it under the terms of the GNU General Public License as published by
0007  * the Free Software Foundation; either version 3 of the License, or (at
0008  * your option) any later version.
0009  *
0010  * This program is distributed in the hope that it will be useful, but
0011  * WITHOUT ANY WARRANTY; without even the implied warranty of
0012  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
0013  * General Public License for more details.
0014  *
0015  * You should have received a copy of the GNU General Public License
0016  * along with this program; if not, write to the Free Software
0017  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
0018  */
0019
0020 #ifndef __GSL_FFT_HALFCOMPLEX_H__
0021 #define __GSL_FFT_HALFCOMPLEX_H__
0022
0023 #include <stddef.h>
0024
0025 #include <gsl/gsl_math.h>
0026 #include <gsl/gsl_complex.h>
0027 #include <gsl/gsl_fft.h>
0028 #include <gsl/gsl_fft_real.h>
0029
0030 #undef __BEGIN_DECLS
0031 #undef __END_DECLS
0032 #ifdef __cplusplus
0033 # define __BEGIN_DECLS extern "C" {
0034 # define __END_DECLS }
0035 #else
0036 # define __BEGIN_DECLS /* empty */
0037 # define __END_DECLS /* empty */
0038 #endif
0039
0040 __BEGIN_DECLS
0041
0042 int gsl_fft_halfcomplex_radix2_backward (double data[], const size_t stride, const size_t n);
0043 int gsl_fft_halfcomplex_radix2_inverse (double data[], const size_t stride, const size_t n);
0044 int gsl_fft_halfcomplex_radix2_transform (double data[], const size_t stride, const size_t n);
0045
0046 typedef struct
0047   {
0048     size_t n;
0049     size_t nf;
0050     size_t factor[64];
0051     gsl_complex *twiddle[64];
0052     gsl_complex *trig;
0053   }
0054 gsl_fft_halfcomplex_wavetable;
0055
0056 gsl_fft_halfcomplex_wavetable * gsl_fft_halfcomplex_wavetable_alloc (size_t n);
0057
0058 void
0059 gsl_fft_halfcomplex_wavetable_free (gsl_fft_halfcomplex_wavetable * wavetable);
0060
0061
0062 int gsl_fft_halfcomplex_backward (double data[], const size_t stride, const size_t n,
0063                                   const gsl_fft_halfcomplex_wavetable * wavetable,
0064                                   gsl_fft_real_workspace * work);
0065
0066 int gsl_fft_halfcomplex_inverse (double data[], const size_t stride, const size_t n,
0067                                  const gsl_fft_halfcomplex_wavetable * wavetable,
0068                                  gsl_fft_real_workspace * work);
0069
0070 int gsl_fft_halfcomplex_transform (double data[], const size_t stride, const size_t n,
0071                                    const gsl_fft_halfcomplex_wavetable * wavetable,
0072                                    gsl_fft_real_workspace * work);
0073
0074 int
0075 gsl_fft_halfcomplex_unpack (const double halfcomplex_coefficient[],
0076                             double complex_coefficient[],
0077                             const size_t stride, const size_t n);
0078
0079 int
0080 gsl_fft_halfcomplex_radix2_unpack (const double halfcomplex_coefficient[],
0081                                    double complex_coefficient[],
0082                                    const size_t stride, const size_t n);
0083
0084 __END_DECLS
0085
0086 #endif /* __GSL_FFT_HALFCOMPLEX_H__ */