Adaptive ODE stepper (GSL) More...
#include <astep_gsl.h>
Detailed Description
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 o2scl::astep_gsl< vec_y_t, vec_dydx_t, vec_yerr_t, func_t >
This class performs an adaptive step of a system of ODEs. To modify the ODE stepper which is used, use the function astep_base::set_step().
Note, this has been updated to correspond to the ode-initval2 functions in GSL.
There is an example for the usage of this class in examples/ex_ode.cpp documented in the Ordinary differential equations example section.
- Todo:
Document what happens when the stepper function returns a non-zero value, as it's different now with the ode-initval2 function.
Document count, failed_steps, etc.
- Idea for Future:
- Compare more directly to GSL
Default template arguments
func_t- ode_functvec_t- boost::numeric::ublas::vector < double >
Definition at line 268 of file astep_gsl.h.
Public Types | |
| typedef boost::numeric::ublas::vector< double > | ubvector |
Public Member Functions | |
| virtual int | astep (double &x, double xmax, double &h, size_t n, vec_y_t &y, vec_dydx_t &dydx_out, vec_yerr_t &yerr, func_t &derivs) |
Make an adaptive integration step of the system derivs. More... | |
| virtual int | astep_derivs (double &x, double xmax, double &h, size_t n, vec_y_t &y, vec_dydx_t &dydx, vec_yerr_t &yerr, func_t &derivs) |
Make an adaptive integration step of the system derivs with derivatives. More... | |
| virtual int | astep_full (double x, double xmax, double &x_out, double &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) |
Make an adaptive integration step of the system derivs. More... | |
 Public Member Functions inherited from o2scl::astep_base< vec_y_t, vec_dydx_t, vec_yerr_t, func_t > | |
| int | set_step (ode_step< vec_y_t, vec_dydx_t, vec_yerr_t, func_t > &step) |
| Set stepper. More... | |
Public Attributes | |
| ode_control_gsl< vec_y_t, vec_dydx_t, vec_yerr_t > | con |
| Control specification. | |
| Public Attributes inherited from o2scl::astep_base< vec_y_t, vec_dydx_t, vec_yerr_t, func_t > | |
| int | verbose |
| Set output level. | |
| ode_rkck_gsl< vec_y_t, vec_dydx_t, vec_yerr_t, func_t > | def_step |
| The default stepper. | |
Protected Member Functions | |
| int | evolve_apply (double t0, double t1, double &t, double &h, size_t nvar, vec_y_t &y, vec_dydx_t &dydx, vec_y_t &yout, vec_yerr_t &yerr, vec_dydx_t &dydx_out, func_t &derivs) |
| Apply the evolution for the next adaptive step. More... | |
Protected Attributes | |
| vec_y_t | yout_int |
| Temporary storage for yout. | |
| vec_dydx_t | dydx_int |
| Internal storage for dydx. | |
| double | last_step |
| The size of the last step. | |
| unsigned long int | count |
| The number of steps. | |
| unsigned long int | failed_steps |
| The number of failed steps. | |
| size_t | msize |
| The size of the allocated vectors. | |
| Protected Attributes inherited from o2scl::astep_base< vec_y_t, vec_dydx_t, vec_yerr_t, func_t > | |
| ode_step< vec_y_t, vec_dydx_t, vec_yerr_t, func_t > * | stepp |
| Pointer to the stepper being used. | |
Member Function Documentation
◆ astep()
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inlinevirtual |
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.
Implements o2scl::astep_base< vec_y_t, vec_dydx_t, vec_yerr_t, func_t >.
Definition at line 461 of file astep_gsl.h.
◆ astep_derivs()
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inlinevirtual |
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.
Implements o2scl::astep_base< vec_y_t, vec_dydx_t, vec_yerr_t, func_t >.
Definition at line 506 of file astep_gsl.h.
◆ astep_full()
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inlinevirtual |
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 xmax. 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.
This adaptive stepper function is faster than astep() or astep_derivs() because it does not require any copying of vectors.
Implements o2scl::astep_base< vec_y_t, vec_dydx_t, vec_yerr_t, func_t >.
Definition at line 557 of file astep_gsl.h.
◆ evolve_apply()
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inlineprotected |
This function is based on gsl_odeiv2_evolve_apply.
- Note
- This function requres that
y,yout,dydxanddydx_outare all distinct vectors.
Definition at line 304 of file astep_gsl.h.
The documentation for this class was generated from the following file:
- /home/awsteiner/wcs/o2scl/src/ode/astep_gsl.h