Class astep_base (o2scl)

O2scl : Class List

template<class vec_y_t = boost::numeric::ublas::vector<double>, class vec_dydx_t = vec_y_t, class vec_yerr_t = vec_y_t, class func_t = ode_funct, class fp_t = double>
class astep_base

Adaptive stepper [abstract base].

The adaptive stepper routines are based on one or many applications of ordinary ODE steppers (implemented in ode_step). Each adaptive stepper (astep_gsl or astep_nonadapt) can be used with any of the ODE stepper classes (e.g. ode_rkck_gsl). By default, ode_rkck_gsl is used. To modify the ODE stepper which is used, use the member function set_step() documented below.

Subclassed by o2scl::astep_gsl< boost::numeric::ublas::vector< double >, boost::numeric::ublas::vector< double >, boost::numeric::ublas::vector< double >, ode_funct<>, double >, o2scl::astep_gsl< ubvector, ubvector, ubvector, ode_funct<>, double >, o2scl::astep_gsl< boost::numeric::ublas::vector< double >, boost::numeric::ublas::vector< double >, boost::numeric::ublas::vector< double >, ode_funct, double >, o2scl::astep_gsl< solve_grid_mat_row, solve_grid_mat_row, solve_grid_mat_row, ode_funct_solve_grid >, o2scl::astep_gsl< std::vector< double >, std::vector< double >, std::vector< double >, ode_funct2, double >, o2scl::astep_gsl< vector< double >, vector< double >, vector< double >, ode_funct >, o2scl::astep_boost< step_t, vec_y_t, vec_dydx_t, vec_yerr_t, func_t, fp_t >, o2scl::astep_gsl< vec_y_t, vec_dydx_t, vec_yerr_t, func_t, fp_t >, o2scl::astep_nonadapt< vec_y_t, vec_dydx_t, vec_yerr_t, func_t, fp_t >

Public Functions

inline astep_base()

inline virtual ~astep_base()

virtual int astep(fp_t &x, fp_t xlimit, fp_t &h, size_t n, vec_y_t &y, vec_dydx_t &dydx_out, vec_yerr_t &yerr, func_t &derivs) = 0

Make an adaptive integration step of the system derivs.

This attempts to take a step of size h from the point x of an n-dimensional system derivs starting with y. On exit, x and y contain the new values at the end of the step, h contains the size of the step, dydx_out contains the derivative at the end of the step, and yerr contains the estimated error at the end of the step.

virtual int astep_derivs(fp_t &x, fp_t xlimit, fp_t &h, size_t n, vec_y_t &y, vec_dydx_t &dydx, vec_yerr_t &yerr, func_t &derivs) = 0

Make an adaptive integration step of the system derivs with derivatives.

This attempts to take a step of size h from the point x of an n-dimensional system derivs starting with y and given the initial derivatives dydx. On exit, x, y and dydx contain the new values at the end of the step, h contains the size of the step, dydx contains the derivative at the end of the step, and yerr contains the estimated error at the end of the step.

virtual int astep_full(fp_t x, fp_t xlimit, fp_t &x_out, fp_t &h, size_t n, vec_y_t &y, vec_dydx_t &dydx, vec_y_t &yout, vec_yerr_t &yerr, vec_dydx_t &dydx_out, func_t &derivs) = 0

Make an adaptive integration step of the system derivs with derivatives.

This function performs an adaptive integration step with the n-dimensional system derivs and parameter pa. It Begins at x with initial stepsize h, ensuring that the step goes no farther than xlimit. At the end of the step, the size of the step taken is h and the new value of x is in x_out. Initially, the function values and derivatives should be specified in y and dydx. The function values, derivatives, and the error at the end of the step are given in yout, yerr, and dydx_out. Unlike in ode_step objects, the objects y, yout, dydx, and dydx_out must all be distinct.

inline int set_step(ode_step<vec_y_t, vec_dydx_t, vec_yerr_t, func_t, fp_t> &step)

Set stepper.

This sets the stepper for use in the adaptive step routine. If no stepper is specified, then the default (def_step of type ode_rkck_gsl) is used.

Public Members

int verbose

Set output level.

ode_rkck_gsl<vec_y_t, vec_dydx_t, vec_yerr_t, func_t, fp_t> def_step

The default stepper.

Protected Attributes

ode_step<vec_y_t, vec_dydx_t, vec_yerr_t, func_t, fp_t> *stepp

Pointer to the stepper being used.