1 /* 2 * Library: lmfit (Levenberg-Marquardt least squares fitting) 3 * 4 * File: lmcurve.c 5 * 6 * Contents: Implements lmcurve_tyd(), a variant of lmcurve() that weighs 7 * data points y(t) with the inverse of the standard deviations dy. 8 * 9 * Copyright: Joachim Wuttke, Forschungszentrum Juelich GmbH (2004-2013) 10 * 11 * License: see ../COPYING (FreeBSD) 12 * 13 * Homepage: apps.jcns.fz-juelich.de/lmfit 14 */ 15 16 #include "lmmin.h" 17 18 typedef struct { 19 const double* t; 20 const double* y; 21 const double* dy; 22 double (*f)(const double t, const double* par); 23 } lmcurve_tyd_data_struct; 24 25 void lmcurve_tyd_evaluate( 26 const double* par, const int m_dat, const void* data, double* fvec, 27 int* info) 28 { 29 lmcurve_tyd_data_struct* D = (lmcurve_tyd_data_struct*)data; 30 int i; 31 for (i = 0; i < m_dat; i++) 32 fvec[i] = ( D->y[i] - D->f(D->t[i], par) ) / D->dy[i]; 33 } 34 35 void lmcurve_tyd( 36 const int n_par, double* par, const int m_dat, 37 const double* t, const double* y, const double* dy, 38 double (*f)(const double t, const double* par), 39 const lm_control_struct* control, lm_status_struct* status) 40 { 41 lmcurve_tyd_data_struct data = { t, y, dy, f }; 42 43 lmmin(n_par, par, m_dat, (const void*)&data, lmcurve_tyd_evaluate, 44 control, status); 45 } 46
