Ikarus::PathFollowing< NLS, PF, ASS > Class Template Reference

The PathFollowing control routine for path-following analysis. More...

#include <ikarus/controlroutines/pathfollowing.hh>

Inheritance diagram for Ikarus::PathFollowing< NLS, PF, ASS >:

Public Types
using	State = PathFollowingStateType< NLS::DifferentiableFunction >
using	MessageType = ControlMessages
using	Callback = std::function< void(ControlMessages, const State &)>
using	Token = std::shared_ptr< Callback >

Public Member Functions
constexpr auto	name () const
	The name of the PathFollowing method. More...
	PathFollowing (const std::shared_ptr< NLS > &nls, int steps, double stepSize, PF pathFollowingType=ArcLength{}, ASS adaptiveStepSizing={})
	Constructor for PathFollowing. More...
ControlInformation	run (typename NLS::Domain &d)
	Executes the PathFollowing routine. More...
NLS &	nonLinearSolver ()
Token	registerListener (Callback callback)
	This method is used to register a Listener function. More...
void	unregisterListener (Token token)
	deregisters a specific function More...
void	notify (ControlMessages message, const State &data)
	This calls all the registered functions. More...

Detailed Description

template<typename NLS, typename PF = ArcLength, typename ASS = AdaptiveStepSizing::NoOp>
requires (Impl::checkPathFollowingTemplates<NLS, PF, ASS>())
class Ikarus::PathFollowing< NLS, PF, ASS >

This class represents the PathFollowing control routine, which utilizes a nonlinear solver, such as Newton's method with scalar subsidiary function, which has to be fulfilled for solving the system along a predefined path.

Consider a non-linear system of equations

\[\mathbf{R}: \require{cases}\begin{cases}\mathbb{R}^n \times \mathbb{R} &\rightarrow \mathbb{R}^n \\ (\mathbf{D},\lambda) &\mapsto \mathbf{R}(\mathbf{D},\lambda) \end{cases}.\]

Then in each step \(k+1\) of the path following algorithm, the following problem is solved

\[ \begin{align} \mathbf{R}(\mathbf{D}_k+ \mathrm{D}\mathbf{D}, \lambda_k+ \mathrm{D} \lambda) &= \mathbf{0} \\ f(\mathrm{D}\mathbf{D}, \mathrm{D} \lambda) &= 0 \end{align} \]

where \(\mathrm{D}\mathbf{D}\) is the increment of the solution vector and \(\mathrm{D} \lambda\) is the load factor increment. The subsidiary function \(f\) is provided by the user and needs to fulfill the concept Concepts::PathFollowingStrategy. This subsidiary function makes the given problem well-posed.

Currently the following subsidiary functions are implemented LoadControlSubsidiaryFunction, ArcLength and DisplacementControl

Template Parameters

NLS	Type of the nonlinear solver used in the control routine.
PF	Type of the path-following strategy.
ASS	Type of the adaptive step sizing strategy.

Member Typedef Documentation

Callback

using Ikarus::Broadcaster< ControlMessages , PathFollowingStateType< NLS::DifferentiableFunction > >::Callback = std::function<void(ControlMessages , const State&)>

inherited

MessageType

using Ikarus::Broadcaster< ControlMessages , PathFollowingStateType< NLS::DifferentiableFunction > >::MessageType = ControlMessages

inherited

State

using Ikarus::ControlRoutineBase< NLS::DifferentiableFunction , PathFollowingStateType< NLS::DifferentiableFunction > , Args >::State = PathFollowingStateType< NLS::DifferentiableFunction >

inherited

Token

using Ikarus::Broadcaster< ControlMessages , PathFollowingStateType< NLS::DifferentiableFunction > >::Token = std::shared_ptr<Callback>

inherited

Constructor & Destructor Documentation

PathFollowing()

template<typename NLS , typename PF = ArcLength, typename ASS = AdaptiveStepSizing::NoOp>

Ikarus::PathFollowing< NLS, PF, ASS >::PathFollowing ( const std::shared_ptr< NLS > &  nls, int  steps, double  stepSize, PF  pathFollowingType = ArcLength{}, ASS  adaptiveStepSizing = {}  )

inline

Parameters

nls	The non linear solver.
steps	Number of steps in the control routine.
stepSize	Size of each step.
pathFollowingType	Type of the path-following function.
adaptiveStepSizing	Type of the adaptive step sizing strategy.

Member Function Documentation

name()

template<typename NLS , typename PF = ArcLength, typename ASS = AdaptiveStepSizing::NoOp>

constexpr auto Ikarus::PathFollowing< NLS, PF, ASS >::name ( ) const

inlineconstexpr

nonLinearSolver()

template<typename NLS , typename PF = ArcLength, typename ASS = AdaptiveStepSizing::NoOp>

NLS & Ikarus::PathFollowing< NLS, PF, ASS >::nonLinearSolver ( )

inline

notify()

void Ikarus::Broadcaster< ControlMessages , PathFollowingStateType< NLS::DifferentiableFunction > >::notify ( ControlMessages  message, const State &  data  )

inlineinherited

registerListener()

Token Ikarus::Broadcaster< ControlMessages , PathFollowingStateType< NLS::DifferentiableFunction > >::registerListener ( Callback  callback )

inlineinherited

The function that is passed in is first stored in a shared_ptr. After this, the shared_ptr is added to the vector of listener functions, which leads to a implicit conversion to a weak_ptr. The shared_ptr is then returned to the Listener that has called this function to be stored in a vector of shared_ptr<void> listener.hh.

Parameters

callback

the callback function

Returns

Token

run()

template<typename NLS , typename PF , typename ASS >
requires (Impl::checkPathFollowingTemplates<NLS, PF, ASS>())

ControlInformation Ikarus::PathFollowing< NLS, PF, ASS >::run

(

typename NLS::Domain &

d

)

• Parameters

  d	The solution.

  Returns

  ControlInformation structure containing information about the control results.

Calculate predictor for a particular step

unregisterListener()

void Ikarus::Broadcaster< ControlMessages , PathFollowingStateType< NLS::DifferentiableFunction > >::unregisterListener ( Token  token )

inlineinherited

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

• pathfollowing.hh
• pathfollowing.inl