Time-derivative interface for BDF2. More...

#include <Tempus_StepperBDF2_decl.hpp>

Inheritance diagram for Tempus::StepperBDF2TimeDerivative< Scalar >:

Public Member Functions
	StepperBDF2TimeDerivative (Scalar dt, Scalar dtOld, Teuchos::RCP< const Thyra::VectorBase< Scalar > > xOld, Teuchos::RCP< const Thyra::VectorBase< Scalar > > xOldOld)
	Constructor.
virtual	~StepperBDF2TimeDerivative ()
	Destructor.
virtual void	compute (Teuchos::RCP< const Thyra::VectorBase< Scalar > > x, Teuchos::RCP< Thyra::VectorBase< Scalar > > xDot, Teuchos::RCP< Thyra::VectorBase< Scalar > > xDotDot=Teuchos::null)
	Compute the time derivative.
virtual void	initialize (Scalar dt, Scalar dtOld, Teuchos::RCP< const Thyra::VectorBase< Scalar > > xOld, Teuchos::RCP< const Thyra::VectorBase< Scalar > > xOldOld)

Private Attributes
Teuchos::RCP< const Thyra::VectorBase< Scalar > >	xOld_
Teuchos::RCP< const Thyra::VectorBase< Scalar > >	xOldOld_
Scalar	dt_
Scalar	dtOld_

Detailed Description

template<typename Scalar>
class Tempus::StepperBDF2TimeDerivative< Scalar >

Time-derivative interface for BDF2.

Given the state $x_n$ , compute the BDF2 time-derivative,

$\‍[ \dot{x}_{n} = \frac{2\tau_n + \tau_{n-1}}{\tau_n + \tau_{n-1}} \left[ \frac{x_n-x_{n-1}}{\tau_n}\right] - \frac{\tau_n}{\tau_n + \tau_{n-1}} \left[ \frac{x_{n-1}-x_{n-2}}{\tau_{n-1}}\right] \‍]$

where

$\‍[ \tau_n = t_n - t_{n-1}. \‍]$

$\ddot{x}$ is not used and set to null.

Definition at line 206 of file Tempus_StepperBDF2_decl.hpp.

Constructor & Destructor Documentation

◆ StepperBDF2TimeDerivative()

template<typename Scalar>

Tempus::StepperBDF2TimeDerivative< Scalar >::StepperBDF2TimeDerivative	(	Scalar	dt,
		Scalar	dtOld,
		Teuchos::RCP< const Thyra::VectorBase< Scalar > >	xOld,
		Teuchos::RCP< const Thyra::VectorBase< Scalar > >	xOldOld )

inline

Constructor.

Definition at line 212 of file Tempus_StepperBDF2_decl.hpp.

◆ ~StepperBDF2TimeDerivative()

template<typename Scalar>

virtual Tempus::StepperBDF2TimeDerivative< Scalar >::~StepperBDF2TimeDerivative ( )

inlinevirtual

Destructor.

Definition at line 218 of file Tempus_StepperBDF2_decl.hpp.

Member Function Documentation

◆ compute()

template<typename Scalar>

virtual void Tempus::StepperBDF2TimeDerivative< Scalar >::compute	(	Teuchos::RCP< const Thyra::VectorBase< Scalar > >	x,
		Teuchos::RCP< Thyra::VectorBase< Scalar > >	xDot,
		Teuchos::RCP< Thyra::VectorBase< Scalar > >	xDotDot = Teuchos::null )

inlinevirtual

Compute the time derivative.

Implements Tempus::TimeDerivative< Scalar >.

Definition at line 221 of file Tempus_StepperBDF2_decl.hpp.

◆ initialize()

template<typename Scalar>

virtual void Tempus::StepperBDF2TimeDerivative< Scalar >::initialize	(	Scalar	dt,
		Scalar	dtOld,
		Teuchos::RCP< const Thyra::VectorBase< Scalar > >	xOld,
		Teuchos::RCP< const Thyra::VectorBase< Scalar > >	xOldOld )