////////////////////////////////////////////////////////////////////// ////////////////////////////////////////////////////////////////////// More...

#include <timesteppers.h>

Inheritance diagram for oomph::NewmarkBDF< NSTEPS >:

Public Member Functions
	NewmarkBDF ()
	Constructor: Pass pointer to global time. We set up a timestepping scheme with NSTEPS+2 doubles to represent the history and the highest deriv is 2. More...

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

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

void	set_weights ()
	Set weights. More...

void	shift_time_values (Data *const &data_pt)
	This function updates the Data's time history so that we can advance to the next timestep. More...

void	shift_time_positions (Node *const &node_pt)
	This function updates a nodal time history so that we can advance to the next timestep. More...

void	enable_degrade_first_derivatives_to_bdf1 ()
	Degrade scheme to first order BDF (for first derivs/veloc); usually for start-up. More...

void	disable_degrade_first_derivatives_to_bdf1 ()
	Disable degradation to first order BDF. More...

void	set_weights ()
	Set weights. More...

void	set_weights ()
	Set weights. More...

void	set_weights ()
	Set weights. More...

Public Member Functions inherited from oomph::Newmark< NSTEPS >
	Newmark ()
	Constructor: Pass pointer to global time. We set up a timestepping scheme with NSTEPS+2 doubles to represent the history and the highest deriv is 2. More...

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

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

unsigned	order () const
	The actual order (accuracy of the scheme) More...

void	assign_initial_values_impulsive (Data *const &data_pt)
	Initialise the time-history for the values, corresponding to an impulsive start. More...

void	assign_initial_positions_impulsive (Node *const &node_pt)
	Initialise the time-history for the values, corresponding to an impulsive start. More...

void	assign_initial_data_values (Data *const &data_pt, Vector< InitialConditionFctPt > initial_value_fct, Vector< InitialConditionFctPt > initial_veloc_fct, Vector< InitialConditionFctPt > initial_accel_fct)
	Initialise the time-history for the Data values, so that the Newmark representations for current veloc and acceleration are exact. More...

void	assign_initial_data_values (Node *const &node_pt, Vector< NodeInitialConditionFctPt > initial_value_fct, Vector< NodeInitialConditionFctPt > initial_veloc_fct, Vector< NodeInitialConditionFctPt > initial_accel_fct)
	Initialise the time-history for the nodal values, so that the Newmark representations for current veloc and acceleration are exact. More...

void	assign_initial_data_values_stage1 (const unsigned t_deriv, Data *const &data_pt)
	First step in a two-stage procedure to assign the history values for the Newmark scheme so that the veloc and accel that are computed by the scheme are correct at the current time. More...

void	assign_initial_data_values_stage2 (Data *const &data_pt)
	Second step in a two-stage procedure to assign the history values for the Newmark scheme so that the veloc and accel that are computed by the scheme are correct at the current time. More...

unsigned	nprev_values () const
	Number of previous values available. More...

unsigned	ndt () const
	Number of timestep increments that need to be stored by the scheme. More...

Public Member Functions inherited from oomph::TimeStepper
	TimeStepper (const unsigned &tstorage, const unsigned &max_deriv)
	Constructor. Pass the amount of storage required by timestepper (present value + history values) and the order of highest time-derivative. More...

	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...

virtual unsigned	nprev_values_for_value_at_evaluation_time () const
	Number of previous values needed to calculate the value at the current time. i.e. how many previous values must we loop over to calculate the values at the evaluation time. For most methods this is 1, i.e. just use the value at t_{n+1}. See midpoint method for a counter-example. More...

void	make_steady ()
	Function to make the time stepper temporarily steady. This is trivially achieved by setting all the weights to zero. More...

bool	is_steady () const
	Flag to indicate if a timestepper has been made steady (possibly temporarily to switch off time-dependence) More...

bool	predict_by_explicit_step () const
	Flag: is adaptivity done by taking a separate step using an ExplicitTimeStepper object? More...

ExplicitTimeStepper *	explicit_predictor_pt ()
	Get the pointer to the explicit timestepper to use as a predictor in adaptivity if Predict_by_explicit_step is set. More...

void	set_predictor_pt (ExplicitTimeStepper *_pred_pt)
	Set the pointer to the explicit timestepper to use as a predictor in adaptivity if Predict_by_explicit_step is set. More...

void	update_predicted_time (const double &new_time)
	Set the time that the current predictions apply for, only needed for paranoid checks when doing Predict_by_explicit_step. More...

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

unsigned	predictor_storage_index () const
	Return the time-index in each Data where predicted values are stored if the timestepper is adaptive. More...

void	enable_warning_in_assign_initial_data_values ()
	Enable the output of warnings due to possible fct pointer vector size mismatch in assign_initial_data_values (Default) More...

void	disable_warning_in_assign_initial_data_values ()
	Disable the output of warnings due to possible fct pointer vector size mismatch in assign_initial_data_values. More...

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

virtual void	undo_make_steady ()
	Reset the is_steady status of a specific TimeStepper to its default and re-assign the weights. More...

std::string	type () const
	Return string that indicates the type of the timestepper (e.g. "BDF", "Newmark", etc.) More...

void	time_derivative (const unsigned &i, Data *const &data_pt, Vector< double > &deriv)
	Evaluate i-th derivative of all values in Data and return in Vector deriv[]. More...

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)
	Evaluate i-th derivative of all values in Node and return in Vector deriv[] (this can't be simply combined with time_derivative(.., Data, ...) because of differences with haning nodes). More...

double	time_derivative (const unsigned &i, Node *const &node_pt, const unsigned &j)
	Evaluate i-th derivative of j-th value in Node. Note the use of the node's value() function so that hanging nodes are taken into account (this is why the functions for Data and Node cannot be combined through simple polymorphism: value is not virtual). More...

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

Time *&	time_pt ()
	Access function for the pointer to time (can't have a paranoid test for null pointers because this is used as a set function). More...

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
	Return the number of doubles required to represent history (one for steady) More...

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

virtual void	set_predictor_weights ()
	Set the weights for the predictor previous timestep (currently empty – overwrite for specific scheme) More...

virtual void	calculate_predicted_values (Data *const &data_pt)
	Do the predictor step for data stored in a Data object (currently empty – overwrite for specific scheme) More...

virtual void	calculate_predicted_positions (Node *const &node_pt)
	Do the predictor step for the positions at a node (currently empty — overwrite for a specific scheme) More...

virtual void	set_error_weights ()
	Set the weights for the error computation, (currently empty – overwrite for specific scheme) More...

virtual double	temporal_error_in_position (Node *const &node_pt, const unsigned &i)
	Compute the error in the position i at a node zero here – overwrite for specific scheme. More...

virtual double	temporal_error_in_value (Data *const &data_pt, const unsigned &i)
	Compute the error in the value i in a Data structure zero here – overwrite for specific scheme. More...

virtual void	actions_before_timestep (Problem *problem_pt)
	Interface for any actions that need to be performed before a time step. More...

virtual void	actions_after_timestep (Problem *problem_pt)
	Interface for any actions that need to be performed after a time step. More...

Private Member Functions
void	set_newmark_veloc_weights (const double &dt)
	Set original Newmark weights for velocities (needed when shifting history values – they're used when updating the previous accelerations and doing this with bdf can make the scheme unstable... More...

Private Attributes
bool	Degrade_to_bdf1_for_first_derivs
	Boolean flag to indicate degradation of scheme to first order BDF (for first derivs/veloc); usually for start-up. More...

Vector< double >	Newmark_veloc_weight
	Original Newmark weights for velocities (needed when shifting history values – they're used when updating the previous accelerations and doing this with bdf can make the scheme unstable... More...

Additional Inherited Members
Public Types inherited from oomph::Newmark< NSTEPS >
typedef double(*	InitialConditionFctPt) (const double &t)
	Typedef for function that returns the (scalar) initial value at a given value of the continuous time t. More...

typedef double(*	NodeInitialConditionFctPt) (const double &t, const Vector< double > &x)
	Typedef for function that returns the (scalar) initial value at a given value of the continuous time t and the spatial coordinate – appropriate for assignement of initial conditions for nodes. More...

Protected Attributes inherited from oomph::Newmark< NSTEPS >
double	Beta1
	First Newmark parameter (usually 0.5) More...

double	Beta2
	Second Newmark parameter (usually 0.5) More...

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
	String that indicates the type of the timestepper (e.g. "BDF", "Newmark", etc.) More...

bool	Adaptive_Flag
	Boolean variable to indicate whether the timestepping scheme can be adaptive. More...

bool	Is_steady
	Bool to indicate if the timestepper is steady, i.e. its time-derivatives evaluate to zero. This status may be achieved temporarily by calling make_steady(). It can be reset to the appropriate default by the function undo_make_steady(). More...

bool	Shut_up_in_assign_initial_data_values
	Boolean to indicate if the timestepper will output warnings when setting possibly an incorrect number of initial data values from function pointers. More...

bool	Predict_by_explicit_step
	Flag: is adaptivity done by taking a separate step using an ExplicitTimeStepper object? More...

ExplicitTimeStepper *	Explicit_predictor_pt
	Pointer to explicit time stepper to use as predictor if Predict_by_explicit_step is set. ??ds merge the two? predict by explicit if pointer is set? More...

double	Predicted_time
	Store the time that the predicted values currently stored are at, to compare for paranoid checks. More...

int	Predictor_storage_index
	The time-index in each Data object where predicted values are stored. -1 if not set. More...

Detailed Description

template<unsigned NSTEPS>
class oomph::NewmarkBDF< NSTEPS >

////////////////////////////////////////////////////////////////////// //////////////////////////////////////////////////////////////////////

Newmark scheme for second time deriv with first derivatives calculated using BDF. . Stored data represents

t=0: value at at present time, Time_pt->time()
t=1: value at previous time, Time_pt->time()-dt
...
t=NSTEPS: value at previous time, Time_pt->time()-NSTEPS*dt
t=NSTEPS+1: 1st time deriv (= "velocity") at previous time, Time_pt->time()-dt
t=NSTEPS+2: 2nd time deriv (= "acceleration") at previous time, Time_pt->time()-dt

NSTEPS=1 gives normal Newmark.

Definition at line 1073 of file timesteppers.h.

Constructor & Destructor Documentation

◆ NewmarkBDF() [1/2]

template<unsigned NSTEPS>

oomph::NewmarkBDF< NSTEPS >::NewmarkBDF ( )

inline

Constructor: Pass pointer to global time. We set up a timestepping scheme with NSTEPS+2 doubles to represent the history and the highest deriv is 2.

Definition at line 1079 of file timesteppers.h.

◆ NewmarkBDF() [2/2]

template<unsigned NSTEPS>

oomph::NewmarkBDF< NSTEPS >::NewmarkBDF ( const NewmarkBDF< NSTEPS > & )

delete

Broken copy constructor.

Member Function Documentation

◆ disable_degrade_first_derivatives_to_bdf1()

template<unsigned NSTEPS>

void oomph::NewmarkBDF< NSTEPS >::disable_degrade_first_derivatives_to_bdf1 ( )

inline

Disable degradation to first order BDF.

Definition at line 1112 of file timesteppers.h.

◆ enable_degrade_first_derivatives_to_bdf1()

template<unsigned NSTEPS>

void oomph::NewmarkBDF< NSTEPS >::enable_degrade_first_derivatives_to_bdf1 ( )

inline

Degrade scheme to first order BDF (for first derivs/veloc); usually for start-up.

Definition at line 1105 of file timesteppers.h.

◆ operator=()

template<unsigned NSTEPS>

void oomph::NewmarkBDF< NSTEPS >::operator= ( const NewmarkBDF< NSTEPS > & )

delete

Broken assignment operator.

◆ set_newmark_veloc_weights()

template<unsigned NSTEPS>

void oomph::NewmarkBDF< NSTEPS >::set_newmark_veloc_weights ( const double & dt )

inlineprivate

Set original Newmark weights for velocities (needed when shifting history values – they're used when updating the previous accelerations and doing this with bdf can make the scheme unstable...

Definition at line 1122 of file timesteppers.h.

References oomph::Time::dt(), and t.

◆ set_weights() [1/4]

void oomph::NewmarkBDF< 1 >::set_weights ( )

virtual

Set weights.

Reimplemented from oomph::Newmark< NSTEPS >.

Definition at line 1185 of file timesteppers.cc.

◆ set_weights() [2/4]

void oomph::NewmarkBDF< 2 >::set_weights ( )

virtual

Set weights.

Reimplemented from oomph::Newmark< NSTEPS >.

Definition at line 1208 of file timesteppers.cc.

References i.

◆ set_weights() [3/4]

void oomph::NewmarkBDF< 4 >::set_weights ( )

virtual

Set weights.

Reimplemented from oomph::Newmark< NSTEPS >.

Definition at line 1247 of file timesteppers.cc.

References i.

◆ set_weights() [4/4]

template<unsigned NSTEPS>

void oomph::NewmarkBDF< NSTEPS >::set_weights ( )

virtual

Set weights.

Reimplemented from oomph::Newmark< NSTEPS >.

◆ shift_time_positions()

template<unsigned NSTEPS>

void oomph::NewmarkBDF< NSTEPS >::shift_time_positions ( Node *const & node_pt )

virtual

This function updates a nodal time history so that we can advance to the next timestep.

Reimplemented from oomph::Newmark< NSTEPS >.

Definition at line 1128 of file timesteppers.cc.

References i, oomph::Node::ndim(), oomph::Node::nposition_type(), oomph::Node::position_is_a_copy(), t, and oomph::Node::x_gen().

◆ shift_time_values()

template<unsigned NSTEPS>

void oomph::NewmarkBDF< NSTEPS >::shift_time_values ( Data *const & data_pt )

virtual

This function updates the Data's time history so that we can advance to the next timestep.

Reimplemented from oomph::Newmark< NSTEPS >.

Definition at line 1082 of file timesteppers.cc.

References i, oomph::Data::is_a_copy(), oomph::Data::nvalue(), oomph::Data::set_value(), t, and oomph::Data::value().

Member Data Documentation

◆ Degrade_to_bdf1_for_first_derivs

template<unsigned NSTEPS>

bool oomph::NewmarkBDF< NSTEPS >::Degrade_to_bdf1_for_first_derivs

private

Boolean flag to indicate degradation of scheme to first order BDF (for first derivs/veloc); usually for start-up.

Definition at line 1139 of file timesteppers.h.

◆ Newmark_veloc_weight

template<unsigned NSTEPS>

Vector<double> oomph::NewmarkBDF< NSTEPS >::Newmark_veloc_weight

private

Original Newmark weights for velocities (needed when shifting history values – they're used when updating the previous accelerations and doing this with bdf can make the scheme unstable...

Definition at line 1145 of file timesteppers.h.

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

Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

template<unsigned NSTEPS> class oomph::NewmarkBDF< NSTEPS >

Constructor & Destructor Documentation

◆ NewmarkBDF() [1/2]

◆ NewmarkBDF() [2/2]

Member Function Documentation

◆ disable_degrade_first_derivatives_to_bdf1()

◆ enable_degrade_first_derivatives_to_bdf1()

◆ operator=()

◆ set_newmark_veloc_weights()

◆ set_weights() [1/4]

◆ set_weights() [2/4]

◆ set_weights() [3/4]

◆ set_weights() [4/4]

◆ shift_time_positions()

◆ shift_time_values()

Member Data Documentation

◆ Degrade_to_bdf1_for_first_derivs

◆ Newmark_veloc_weight

template<unsigned NSTEPS>
class oomph::NewmarkBDF< NSTEPS >