#include <implicit_midpoint_rule.h>

Inheritance diagram for oomph::IMR:

Public Member Functions
	IMR (const bool &adaptive=false)
	Constructor with initialisation. More...

virtual	~IMR ()
	Destructor, predictor_pt handled by base. More...

void	set_weights ()
	Setup weights for time derivative calculations. More...

unsigned	nprev_values_for_value_at_evaluation_time () const

Public Member Functions inherited from oomph::IMRBase
	IMRBase (const bool &adaptive=false)
	Constructor with initialisation. More...

virtual	~IMRBase ()
	Destructor. More...

unsigned	order () const
	Actual order (accuracy) of the scheme. More...

unsigned	ndt () const
	Number of timestep increments that are required by the scheme. More...

unsigned	nprev_values () const
	??ds More...

void	shift_time_values (Data *const &data_pt)

void	shift_time_positions (Node *const &node_pt)

void	set_error_weights ()

void	set_predictor_weights ()

void	assign_initial_values_impulsive (Data *const &data_pt)
	not implemented (??ds TODO) More...

void	assign_initial_positions_impulsive (Node *const &node_pt)

void	calculate_predicted_positions (Node *const &node_pt)

double	temporal_error_in_position (Node *const &node_pt, const unsigned &i)

void	calculate_predicted_values (Data *const &data_pt)

double	temporal_error_in_value (Data *const &data_pt, const unsigned &i)

Public Member Functions inherited from oomph::TimeStepper
	TimeStepper (const unsigned &tstorage, const unsigned &max_deriv)

	TimeStepper ()
	Broken empty constructor. More...

	TimeStepper (const TimeStepper &)=delete
	Broken copy constructor. More...

void	operator= (const TimeStepper &)=delete
	Broken assignment operator. More...

virtual	~TimeStepper ()
	virtual destructor More...

unsigned	highest_derivative () const
	Highest order derivative that the scheme can compute. More...

double &	time ()
	Return current value of continous time. More...

double	time () const
	Return current value of continous time. More...

void	make_steady ()

bool	is_steady () const

bool	predict_by_explicit_step () const

ExplicitTimeStepper *	explicit_predictor_pt ()

void	set_predictor_pt (ExplicitTimeStepper *_pred_pt)

void	update_predicted_time (const double &new_time)

void	check_predicted_values_up_to_date () const
	Check that the predicted values are the ones we want. More...

unsigned	predictor_storage_index () const

void	enable_warning_in_assign_initial_data_values ()

void	disable_warning_in_assign_initial_data_values ()

const DenseMatrix< double > *	weights_pt () const
	Get a (const) pointer to the weights. More...

virtual void	undo_make_steady ()

std::string	type () const

void	time_derivative (const unsigned &i, Data *const &data_pt, Vector< double > &deriv)

double	time_derivative (const unsigned &i, Data *const &data_pt, const unsigned &j)
	Evaluate i-th derivative of j-th value in Data. More...

void	time_derivative (const unsigned &i, Node *const &node_pt, Vector< double > &deriv)

double	time_derivative (const unsigned &i, Node *const &node_pt, const unsigned &j)

Time *const &	time_pt () const
	Access function for the pointer to time (const version) More...

Time *&	time_pt ()

virtual double	weight (const unsigned &i, const unsigned &j) const
	Access function for j-th weight for the i-th derivative. More...

unsigned	ntstorage () const

bool	adaptive_flag () const
	Function to indicate whether the scheme is adaptive (false by default) More...

virtual void	actions_before_timestep (Problem *problem_pt)

virtual void	actions_after_timestep (Problem *problem_pt)

Private Member Functions
	IMR (const IMR &dummy)
	Inaccessible copy constructor. More...

void	operator= (const IMR &dummy)
	Inaccessible assignment operator. More...

Additional Inherited Members
Protected Attributes inherited from oomph::TimeStepper
Time *	Time_pt
	Pointer to discrete time storage scheme. More...

DenseMatrix< double >	Weight
	Storage for the weights associated with the timestepper. More...

std::string	Type

bool	Adaptive_Flag

bool	Is_steady

bool	Shut_up_in_assign_initial_data_values

bool	Predict_by_explicit_step

ExplicitTimeStepper *	Explicit_predictor_pt

double	Predicted_time

int	Predictor_storage_index

Detailed Description

The "real" implementation of the implicit midpoint rule. Implemented by calculation of residuals etc. at half step. This requires non-trivial modifications to the element's residual and Jacobian calculation functions to interpolate values to the midpoint. As such IMRByBDF should be preferred.

However this class must be used when multiple different time steppers are being used simultaneously for different parts of the problem.

Constructor & Destructor Documentation

◆ IMR() [1/2]

oomph::IMR::IMR ( const bool & adaptive = false )

inline

Constructor with initialisation.

Common mistakes when using this implementation of midpoint:

Didn't include the d_u_evaltime_by_du_np1 term in the Jacobian.
Didn't properly interpolate time/values/x/derivatives in jacobian/residual (all of these MUST be evaluated at the midpoint).

176 : IMRBase(adaptive) {}

oomph::IMRBase::IMRBase

IMRBase(const bool &adaptive=false)

Constructor with initialisation.

Definition: implicit_midpoint_rule.h:47

Global_Physical_Variables::adaptive

int adaptive

Definition: jeffery_hamel.cc:106

◆ ~IMR()

virtual oomph::IMR::~IMR ( )

inlinevirtual

Destructor, predictor_pt handled by base.

179 {}

◆ IMR() [2/2]

oomph::IMR::IMR ( const IMR & dummy )

inlineprivate

Inaccessible copy constructor.

205 {}

Member Function Documentation

◆ nprev_values_for_value_at_evaluation_time()

unsigned oomph::IMR::nprev_values_for_value_at_evaluation_time ( ) const

inlinevirtual

Number of history values to interpolate over to get the "current" value.

Implements oomph::IMRBase.

     {
       return 2;
     }

◆ operator=()

void oomph::IMR::operator= ( const IMR & dummy )

inlineprivate

Inaccessible assignment operator.

208 {}

◆ set_weights()

void oomph::IMR::set_weights ( )

inlinevirtual

Setup weights for time derivative calculations.

Implements oomph::IMRBase.

     {
       // Set the weights for zero-th derivative (i.e. the value to use in
       // newton solver calculations, implicit midpoint method uses the
       // average of previous and current values).
       Weight(0, 0) = 0.5;
       Weight(0, 1) = 0.5;
  
       // Set the weights for 1st time derivative
       double dt = Time_pt->dt(0);
       Weight(1, 0) = 1.0 / dt;
       Weight(1, 1) = -1.0 / dt;
     }

References oomph::Time::dt(), oomph::TimeStepper::Time_pt, and oomph::TimeStepper::Weight.

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

implicit_midpoint_rule.h

Public Member Functions

Private Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ IMR() [1/2]

◆ ~IMR()

◆ IMR() [2/2]

Member Function Documentation

◆ nprev_values_for_value_at_evaluation_time()

◆ operator=()

◆ set_weights()