File indexing completed on 2024-05-12 15:27:06
0001 /*************************************************************************** 0002 File : nsl_corr.h 0003 Project : LabPlot 0004 Description : NSL discrete correlation functions 0005 -------------------------------------------------------------------- 0006 Copyright : (C) 2018 by Stefan Gerlach (stefan.gerlach@uni.kn) 0007 0008 ***************************************************************************/ 0009 0010 /*************************************************************************** 0011 * * 0012 * This program is free software; you can redistribute it and/or modify * 0013 * it under the terms of the GNU General Public License as published by * 0014 * the Free Software Foundation; either version 2 of the License, or * 0015 * (at your option) any later version. * 0016 * * 0017 * This program is distributed in the hope that it will be useful, * 0018 * but WITHOUT ANY WARRANTY; without even the implied warranty of * 0019 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * 0020 * GNU General Public License for more details. * 0021 * * 0022 * You should have received a copy of the GNU General Public License * 0023 * along with this program; if not, write to the Free Software * 0024 * Foundation, Inc., 51 Franklin Street, Fifth Floor, * 0025 * Boston, MA 02110-1301 USA * 0026 * * 0027 ***************************************************************************/ 0028 0029 #ifndef NSL_CORR_H 0030 #define NSL_CORR_H 0031 0032 #include <stdlib.h> 0033 0034 #define NSL_CORR_TYPE_COUNT 2 0035 /* linear (zero-padded), circular */ 0036 typedef enum {nsl_corr_type_linear, nsl_corr_type_circular} nsl_corr_type_type; 0037 extern const char* nsl_corr_type_name[]; 0038 0039 #define NSL_CORR_NORM_COUNT 4 0040 /* how to normalize (see octave) 0041 * biased - 1/N 0042 * unbiased - 1/(N-|m|) 0043 * coeff - 1/sqrt(R_xx(0) R_yy(0)) = 1/sqrt(sum x_i^2 sum y_i^2) [used in Origin] 0044 * */ 0045 typedef enum {nsl_corr_norm_none, nsl_corr_norm_biased, nsl_corr_norm_unbiased, nsl_corr_norm_coeff} nsl_corr_norm_type; 0046 extern const char* nsl_corr_norm_name[]; 0047 0048 0049 int nsl_corr_correlation(double s[], size_t n, double r[], size_t m, nsl_corr_type_type, nsl_corr_norm_type normalize, double out[]); 0050 0051 /* linear/circular correlation using FFT method 0052 * s and r are untouched 0053 */ 0054 int nsl_corr_fft_type(double s[], size_t n, double r[], size_t m, nsl_corr_type_type, nsl_corr_norm_type normalize, double out[]); 0055 /* actual FFT method calculation using zero-padded arrays 0056 * uses FFTW if available and GSL otherwise 0057 * s and r are overwritten 0058 */ 0059 #ifdef HAVE_FFTW3 0060 int nsl_corr_fft_FFTW(double s[], double r[], size_t n, double out[]); 0061 #endif 0062 int nsl_corr_fft_GSL(double s[], double r[], size_t n, double out[]); 0063 0064 #endif /* NSL_CORR_H */