num_collect::ode::pi_step_size_controller< Formula > Class Template Reference

Class to control step sizes using PI controller [8]. More...

#include <num_collect/ode/pi_step_size_controller.h>

Inheritance diagram for num_collect::ode::pi_step_size_controller< Formula >:

Collaboration diagram for num_collect::ode::pi_step_size_controller< Formula >:

Public Types
using	base_type
	Base class.
Public Types inherited from num_collect::ode::step_size_controller_base< pi_step_size_controller< Formula >, Formula >
using	formula_type
	Type of formula.
using	problem_type
	Type of problem.
using	scalar_type
	Type of scalars.
using	variable_type
	Type of variables.

Public Member Functions
	pi_step_size_controller ()
	Constructor.
auto	check_and_calc_next (scalar_type &step_size, const variable_type &variable, const variable_type &error) -> bool
	Check the error estimate and calculate the next step size.
auto	current_step_error_exponent (const scalar_type &val) -> pi_step_size_controller &
	Set the exponent of the error of the current time step.
void	init ()
	Initialize.
auto	max_step_size_factor (const scalar_type &val) -> pi_step_size_controller &
	Set the maximum factor of step sizes.
auto	min_step_size_factor (const scalar_type &val) -> pi_step_size_controller &
	Set the minimum factor of step sizes.
auto	previous_step_error_exponent (const scalar_type &val) -> pi_step_size_controller &
	Set the exponent of the error of the previous time step.
auto	step_size_factor_safety_coeff (const scalar_type &val) -> pi_step_size_controller &
	Set the safety coefficient for factors of step sizes.
Public Member Functions inherited from num_collect::ode::step_size_controller_base< pi_step_size_controller< Formula >, Formula >
auto	limits () const -> const step_size_limits< scalar_type > &
	Get the limits of step sizes.
auto	limits (const step_size_limits< scalar_type > &val) -> pi_step_size_controller< Formula > &
	Set the limits of step sizes.
auto	reduction_rate (const scalar_type &val) -> pi_step_size_controller< Formula > &
	Set the rate to reduce step sizes when error is large.
auto	tolerances () const -> const error_tolerances< variable_type > &
	Get the error tolerances.
auto	tolerances (const error_tolerances< variable_type > &val) -> pi_step_size_controller< Formula > &
	Set the error tolerances.
Public Member Functions inherited from num_collect::logging::logging_mixin
	logging_mixin (log_tag_view tag)
	Constructor.
template<typename Child >
void	configure_child_algorithm_logger_if_exists (Child &child)
	Configure a logger of a child algorithm if exists.
auto	logger () const noexcept -> const num_collect::logging::logger &
	Access to the logger.
auto	logger () noexcept -> num_collect::logging::logger &
	Access to the logger.

Static Public Attributes
static constexpr scalar_type	default_current_step_error_exponent
	Default exponent of the error of the current time step.
static constexpr scalar_type	default_previous_step_error_exponent
	Default exponent of the error of the previous time step.
static constexpr index_type	formula_order_for_exponent
	Order of the formula used in exponents.

Private Member Functions
void	calc_next (scalar_type &step_size, const variable_type &variable, const variable_type &error)
	Calculate the next step size.

Private Attributes
scalar_type	current_step_error_exponent_
	Exponent of the error of the current time step.
scalar_type	max_step_size_factor_ {default_max_step_size_factor}
	Maximum factor of step sizes.
scalar_type	min_step_size_factor_ {default_min_step_size_factor}
	Minimum factor of step sizes.
scalar_type	previous_step_error_ {static_cast<scalar_type>(1)}
	Error of the previous time step.
scalar_type	previous_step_error_exponent_
	Exponent of the error of the previous time step.
scalar_type	step_size_factor_safety_coeff_
	Safety coefficient for factors of step sizes.

Static Private Attributes
static constexpr auto	default_max_step_size_factor
	Default maximum factor of step sizes.
static constexpr auto	default_min_step_size_factor
	Default minimum factor of step sizes.
static constexpr auto	default_step_size_factor_safety_coeff
	Default safety coefficient for factors of step sizes.

Additional Inherited Members
Protected Member Functions inherited from num_collect::ode::step_size_controller_base< pi_step_size_controller< Formula >, Formula >
	step_size_controller_base (logging::log_tag_view tag)
	Constructor.
auto	derived () const noexcept -> const pi_step_size_controller< Formula > &
	Access derived object.
auto	derived () noexcept -> pi_step_size_controller< Formula > &
	Access derived object.
auto	reduce_if_needed (scalar_type &step_size, const variable_type &variable, const variable_type &error) -> bool
	Reduce step size if needed.

Detailed Description

template<concepts::formula Formula>
class num_collect::ode::pi_step_size_controller< Formula >

Class to control step sizes using PI controller [8].

Template Parameters

Formula

Type of the formula.

Definition at line 47 of file pi_step_size_controller.h.

Member Typedef Documentation

base_type

template<concepts::formula Formula>

using num_collect::ode::pi_step_size_controller< Formula >::base_type

Initial value:

 
        step_size_controller_base<pi_step_size_controller<Formula>, Formula>

Base class.

Definition at line 52 of file pi_step_size_controller.h.

Constructor & Destructor Documentation

pi_step_size_controller()

template<concepts::formula Formula>

num_collect::ode::pi_step_size_controller< Formula >::pi_step_size_controller ( )

inline

Constructor.

Definition at line 85 of file pi_step_size_controller.h.

Member Function Documentation

calc_next()

template<concepts::formula Formula>

void num_collect::ode::pi_step_size_controller< Formula >::calc_next ( scalar_type & step_size, const variable_type & variable, const variable_type & error )

inlineprivate

Calculate the next step size.

Parameters

[in,out]	step_size	Step size.
[in]	variable	Variable.
[in]	error	Error estimate.

Definition at line 197 of file pi_step_size_controller.h.

check_and_calc_next()

template<concepts::formula Formula>

auto num_collect::ode::pi_step_size_controller< Formula >::check_and_calc_next ( scalar_type & step_size, const variable_type & variable, const variable_type & error ) -> bool

inlinenodiscard

Check the error estimate and calculate the next step size.

Parameters

[in,out]	step_size	Step size.
[in]	variable	Variable.
[in]	error	Error estimate.

Return values

true	Given error satisfies tolerances.
false	Given error doesn't satisfy tolerances.

Definition at line 103 of file pi_step_size_controller.h.

current_step_error_exponent()

template<concepts::formula Formula>

auto num_collect::ode::pi_step_size_controller< Formula >::current_step_error_exponent ( const scalar_type & val ) -> pi_step_size_controller&

inline

Set the exponent of the error of the current time step.

Parameters

[in]

val

Value.

Returns

This.

Definition at line 118 of file pi_step_size_controller.h.

init()

template<concepts::formula Formula>

void num_collect::ode::pi_step_size_controller< Formula >::init ( )

inline

Initialize.

Definition at line 90 of file pi_step_size_controller.h.

max_step_size_factor()

template<concepts::formula Formula>

auto num_collect::ode::pi_step_size_controller< Formula >::max_step_size_factor ( const scalar_type & val ) -> pi_step_size_controller&

inline

Set the maximum factor of step sizes.

Parameters

[in]

val

Value.

Returns

This.

Definition at line 164 of file pi_step_size_controller.h.

min_step_size_factor()

template<concepts::formula Formula>

auto num_collect::ode::pi_step_size_controller< Formula >::min_step_size_factor ( const scalar_type & val ) -> pi_step_size_controller&

inline

Set the minimum factor of step sizes.

Parameters

[in]

val

Value.

Returns

This.

Definition at line 179 of file pi_step_size_controller.h.

previous_step_error_exponent()

template<concepts::formula Formula>

auto num_collect::ode::pi_step_size_controller< Formula >::previous_step_error_exponent ( const scalar_type & val ) -> pi_step_size_controller&

inline

Set the exponent of the error of the previous time step.

Parameters

[in]

val

Value.

Returns

This.

Definition at line 133 of file pi_step_size_controller.h.

step_size_factor_safety_coeff()

template<concepts::formula Formula>

auto num_collect::ode::pi_step_size_controller< Formula >::step_size_factor_safety_coeff ( const scalar_type & val ) -> pi_step_size_controller&

inline

Set the safety coefficient for factors of step sizes.

Parameters

[in]

val

Value.

Returns

This.

Definition at line 149 of file pi_step_size_controller.h.

Member Data Documentation

current_step_error_exponent_

template<concepts::formula Formula>

scalar_type num_collect::ode::pi_step_size_controller< Formula >::current_step_error_exponent_

private

Initial value:

{
        default_current_step_error_exponent}

Exponent of the error of the current time step.

Definition at line 230 of file pi_step_size_controller.h.

default_current_step_error_exponent

template<concepts::formula Formula>

scalar_type num_collect::ode::pi_step_size_controller< Formula >::default_current_step_error_exponent

staticconstexpr

Initial value:

=
        static_cast<scalar_type>(0.7) /
        static_cast<scalar_type>(formula_order_for_exponent + 1)

Default exponent of the error of the current time step.

This is a value proposed by [8].

Definition at line 69 of file pi_step_size_controller.h.

default_max_step_size_factor

template<concepts::formula Formula>

auto num_collect::ode::pi_step_size_controller< Formula >::default_max_step_size_factor

staticconstexprprivate

Initial value:

=
        static_cast<scalar_type>(2)

Default maximum factor of step sizes.

Definition at line 246 of file pi_step_size_controller.h.

default_min_step_size_factor

template<concepts::formula Formula>

auto num_collect::ode::pi_step_size_controller< Formula >::default_min_step_size_factor

staticconstexprprivate

Initial value:

=
        static_cast<scalar_type>(0.1)

Default minimum factor of step sizes.

Definition at line 253 of file pi_step_size_controller.h.

default_previous_step_error_exponent

template<concepts::formula Formula>

scalar_type num_collect::ode::pi_step_size_controller< Formula >::default_previous_step_error_exponent

staticconstexpr

Initial value:

=
        static_cast<scalar_type>(0.4) /
        static_cast<scalar_type>(formula_order_for_exponent + 1)

Default exponent of the error of the previous time step.

This is a value proposed by [8].

Definition at line 78 of file pi_step_size_controller.h.

default_step_size_factor_safety_coeff

template<concepts::formula Formula>

auto num_collect::ode::pi_step_size_controller< Formula >::default_step_size_factor_safety_coeff

staticconstexprprivate

Initial value:

=
        static_cast<scalar_type>(0.9)

Default safety coefficient for factors of step sizes.

Definition at line 238 of file pi_step_size_controller.h.

formula_order_for_exponent

template<concepts::formula Formula>

index_type num_collect::ode::pi_step_size_controller< Formula >::formula_order_for_exponent

staticconstexpr

Initial value:

=
        impl::get_least_known_order<formula_type>()

Order of the formula used in exponents.

Definition at line 61 of file pi_step_size_controller.h.

max_step_size_factor_

template<concepts::formula Formula>

scalar_type num_collect::ode::pi_step_size_controller< Formula >::max_step_size_factor_ {default_max_step_size_factor}

private

Maximum factor of step sizes.

Definition at line 250 of file pi_step_size_controller.h.

min_step_size_factor_

template<concepts::formula Formula>

scalar_type num_collect::ode::pi_step_size_controller< Formula >::min_step_size_factor_ {default_min_step_size_factor}

private

Minimum factor of step sizes.

Definition at line 257 of file pi_step_size_controller.h.

previous_step_error_

template<concepts::formula Formula>

scalar_type num_collect::ode::pi_step_size_controller< Formula >::previous_step_error_ {static_cast<scalar_type>(1)}

private

Error of the previous time step.

Definition at line 227 of file pi_step_size_controller.h.

previous_step_error_exponent_

template<concepts::formula Formula>

scalar_type num_collect::ode::pi_step_size_controller< Formula >::previous_step_error_exponent_

private

Initial value:

{
        default_previous_step_error_exponent}

Exponent of the error of the previous time step.

Definition at line 234 of file pi_step_size_controller.h.

step_size_factor_safety_coeff_

template<concepts::formula Formula>

scalar_type num_collect::ode::pi_step_size_controller< Formula >::step_size_factor_safety_coeff_

private

Initial value:

{
        default_step_size_factor_safety_coeff}

Safety coefficient for factors of step sizes.

Definition at line 242 of file pi_step_size_controller.h.

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The documentation for this class was generated from the following file:

• include/num_collect/ode/pi_step_size_controller.h