File indexing completed on 2024-05-12 15:27:06
0001 /*************************************************************************** 0002 File : nsl_diff.h 0003 Project : LabPlot 0004 Description : NSL numerical differentiation functions 0005 -------------------------------------------------------------------- 0006 Copyright : (C) 2016 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_DIFF_H 0030 #define NSL_DIFF_H 0031 0032 #include <stdlib.h> 0033 0034 #define NSL_DIFF_DERIV_ORDER_COUNT 6 0035 typedef enum {nsl_diff_deriv_order_first, nsl_diff_deriv_order_second, nsl_diff_deriv_order_third, 0036 nsl_diff_deriv_order_fourth, nsl_diff_deriv_order_fifth, nsl_diff_deriv_order_sixth} nsl_diff_deriv_order_type; 0037 extern const char* nsl_diff_deriv_order_name[]; 0038 0039 /************ finite differences *********/ 0040 0041 /* first derivative, central 0042 remark: do we need this? 0043 */ 0044 double nsl_diff_first_central(double xm, double fm, double xp, double fp); 0045 0046 /************ first derivatives *********/ 0047 0048 /* calculates derivative of n points of xy-data. 0049 for equal/unequal spaced data. 0050 result in y 0051 */ 0052 int nsl_diff_first_deriv_equal(const double *x, double *y, const size_t n); 0053 int nsl_diff_first_deriv(const double *x, double *y, const size_t n, int order); 0054 int nsl_diff_first_deriv_second_order(const double *x, double *y, const size_t n); 0055 int nsl_diff_first_deriv_fourth_order(const double *x, double *y, const size_t n); 0056 /* using average between left and right diff (like in other programs) */ 0057 int nsl_diff_first_deriv_avg(const double *x, double *y, const size_t n); 0058 0059 /************ second derivatives *********/ 0060 0061 /* calculates second derivative of n points of xy-data 0062 for unequal spaced data. 0063 result in y 0064 */ 0065 int nsl_diff_second_deriv(const double *x, double *y, const size_t n, int order); 0066 int nsl_diff_second_deriv_first_order(const double *x, double *y, const size_t n); 0067 int nsl_diff_second_deriv_second_order(const double *x, double *y, const size_t n); 0068 int nsl_diff_second_deriv_third_order(const double *x, double *y, const size_t n); 0069 0070 /************ third derivatives *********/ 0071 0072 /* calculates third derivative of n points of xy-data 0073 for unequal spaced data. 0074 result in y 0075 */ 0076 int nsl_diff_third_deriv(const double *x, double *y, const size_t n, int order); 0077 int nsl_diff_third_deriv_second_order(const double *x, double *y, const size_t n); 0078 0079 /************ fourth derivatives *********/ 0080 0081 /* calculates fourth derivative of n points of xy-data 0082 for unequal spaced data. 0083 result in y 0084 */ 0085 int nsl_diff_fourth_deriv(const double *x, double *y, const size_t n, int order); 0086 int nsl_diff_fourth_deriv_first_order(const double *x, double *y, const size_t n); 0087 int nsl_diff_fourth_deriv_third_order(const double *x, double *y, const size_t n); 0088 0089 /************ fifth derivatives *********/ 0090 0091 /* calculates fifth derivative of n points of xy-data 0092 for unequal spaced data. 0093 result in y 0094 */ 0095 int nsl_diff_fifth_deriv(const double *x, double *y, const size_t n, int order); 0096 int nsl_diff_fifth_deriv_second_order(const double *x, double *y, const size_t n); 0097 0098 /************ sixth derivatives *********/ 0099 0100 /* calculates sixth derivative of n points of xy-data 0101 for unequal spaced data. 0102 result in y 0103 */ 0104 int nsl_diff_sixth_deriv(const double *x, double *y, const size_t n, int order); 0105 int nsl_diff_sixth_deriv_first_order(const double *x, double *y, const size_t n); 0106 0107 #endif /* NSL_DIFF_H */