diff options
Diffstat (limited to 'src/c/differential_calculus/ode/dodea.c')
-rw-r--r-- | src/c/differential_calculus/ode/dodea.c | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/src/c/differential_calculus/ode/dodea.c b/src/c/differential_calculus/ode/dodea.c new file mode 100644 index 00000000..ff3cbdec --- /dev/null +++ b/src/c/differential_calculus/ode/dodea.c @@ -0,0 +1,49 @@ +/* Copyright (C) 2016 - IIT Bombay - FOSSEE + + This file must be used under the terms of the CeCILL. + This source file is licensed as described in the file COPYING, which + you should have received as part of this distribution. The terms + are also available at + http://www.cecill.info/licences/Licence_CeCILL_V2-en.txt + Author: Siddhesh Wani + Organization: FOSSEE, IIT Bombay + Email: toolbox@scilab.in +*/ + +//Function for solving ODEs using GSL library + +#include "ode.h" +#include "types.h" +#include <gsl/gsl_errno.h> +#include <gsl/gsl_matrix.h> +#include <gsl/gsl_odeiv2.h> + + +void dodea(double *initial_value, double start_time, double end_time, \ + char *ode_function, double nequs, double eps_abs, double eps_rel, \ + double step_size, int *params, double *out) +{ + double t = start_time; + //Initialise output to initial state + int counter = 0; + for (counter = 0; counter<nequs;counter++) + { + out[counter] = initial_value[counter]; + } + + //Setup ODE related parameters + gsl_odeiv2_system sys = {ode_function, NULL, 2, params}; + + gsl_odeiv2_step *s = gsl_odeiv2_step_alloc (gsl_odeiv2_step_rkf45, nequs); + gsl_odeiv2_control *c = gsl_odeiv2_control_y_new (eps_abs, eps_rel); + gsl_odeiv2_evolve *e = gsl_odeiv2_evolve_alloc (nequs); + + while(t < end_time) + { + gsl_odeiv2_evolve_apply_fixed_step (e, c, s, &sys, &t, step_size, out); + } + + gsl_odeiv2_evolve_free (e); + gsl_odeiv2_control_free (c); + gsl_odeiv2_step_free (s); +} |