mfem::CVODESolver Class Reference

Interface to the CVODE library – linear multi-step methods. More...

#include <sundials.hpp>

Inheritance diagram for mfem::CVODESolver:

Collaboration diagram for mfem::CVODESolver:

Public Member Functions
	CVODESolver (int lmm)
	Construct a serial wrapper to SUNDIALS' CVODE integrator.
	CVODESolver (MPI_Comm comm, int lmm)
	Construct a parallel wrapper to SUNDIALS' CVODE integrator.
void	Init (TimeDependentOperator &f_) override
	Initialize CVODE: calls CVodeCreate() to create the CVODE memory and set some defaults.
void	Step (Vector &x, double &t, double &dt) override
	Integrate the ODE with CVODE using the specified step mode.
void	UseMFEMLinearSolver ()
	Attach the linear system setup and solve methods from the TimeDependentOperator i.e., SUNImplicitSetup() and SUNImplicitSolve() to CVODE.
void	UseSundialsLinearSolver ()
	Attach SUNDIALS GMRES linear solver to CVODE.
void	SetStepMode (int itask)
	Select the CVODE step mode: CV_NORMAL (default) or CV_ONE_STEP.
void	SetSStolerances (double reltol, double abstol)
	Set the scalar relative and scalar absolute tolerances.
void	SetSVtolerances (double reltol, Vector abstol)
	Set the scalar relative and vector of absolute tolerances.
void	SetRootFinder (int components, RootFunction func)
	Initialize Root Finder.
void	SetMaxStep (double dt_max)
	Set the maximum time step.
void	SetMaxNSteps (int steps)
	Set the maximum number of time steps.
long	GetNumSteps ()
	Get the number of internal steps taken so far.
void	SetMaxOrder (int max_order)
	Set the maximum method order.
void	PrintInfo () const
	Print various CVODE statistics.
virtual	~CVODESolver ()
	Destroy the associated CVODE memory and SUNDIALS objects.
Public Member Functions inherited from mfem::ODESolver
	ODESolver ()
virtual void	Step (Vector &x, real_t &t, real_t &dt)=0
	Perform a time step from time t [in] to time t [out] based on the requested step size dt [in].
virtual void	Run (Vector &x, real_t &t, real_t &dt, real_t tf)
	Perform time integration from time t [in] to time tf [in].
virtual int	GetStateSize ()
	Returns how many State vectors the ODE requires.
virtual	~ODESolver ()
Public Member Functions inherited from mfem::SundialsSolver
void *	GetMem () const
	Access the SUNDIALS memory structure.
int	GetFlag () const
	Returns the last flag returned by a call to a SUNDIALS function.

Protected Types
typedef std::function< int(sunrealtype t, Vector y, Vector gout, CVODESolver *)>	RootFunction
	Typedef for root finding functions.
typedef std::function< int(Vector y, Vector w, CVODESolver *)>	EWTFunction
	Typedef declaration for error weight functions.

Static Protected Member Functions
static int	RHS (sunrealtype t, const N_Vector y, N_Vector ydot, void *user_data)
	Number of components in gout.
static int	LinSysSetup (sunrealtype t, N_Vector y, N_Vector fy, SUNMatrix A, sunbooleantype jok, sunbooleantype *jcur, sunrealtype gamma, void *user_data, N_Vector tmp1, N_Vector tmp2, N_Vector tmp3)
	Setup the linear system \( A x = b \).
static int	LinSysSolve (SUNLinearSolver LS, SUNMatrix A, N_Vector x, N_Vector b, sunrealtype tol)
	Solve the linear system \( A x = b \).
static int	root (sunrealtype t, N_Vector y, sunrealtype *gout, void *user_data)
	Prototype to define root finding for CVODE.

Protected Attributes
int	lmm_type
	Linear multistep method type.
int	step_mode
	CVODE step mode (CV_NORMAL or CV_ONE_STEP).
int	root_components
RootFunction	root_func
	A class member to facilitate pointing to a user-specified root function.
EWTFunction	ewt_func
	A class member to facilitate pointing to a user-specified error weight function.
Protected Attributes inherited from mfem::ODESolver
TimeDependentOperator *	f
	Pointer to the associated TimeDependentOperator.
MemoryType	mem_type
Protected Attributes inherited from mfem::SundialsSolver
void *	sundials_mem
	SUNDIALS mem structure.
int	flag
	Last flag returned from a call to SUNDIALS.
bool	reinit
	Flag to signal memory reinitialization is need.
long	saved_global_size
	Global vector length on last initialization.
SundialsNVector *	Y
	State vector.
SUNMatrix	A
SUNMatrix	M
	Mass matrix M.
SUNLinearSolver	LSA
	Linear solver for A.
SUNLinearSolver	LSM
	Linear solver for M.
SUNNonlinearSolver	NLS
	Nonlinear solver.

Additional Inherited Members
Static Public Member Functions inherited from mfem::ODESolver
static MFEM_EXPORT std::unique_ptr< ODESolver >	Select (const int ode_solver_type)
static MFEM_EXPORT std::unique_ptr< ODESolver >	SelectExplicit (const int ode_solver_type)
static MFEM_EXPORT std::unique_ptr< ODESolver >	SelectImplicit (const int ode_solver_type)
Static Public Attributes inherited from mfem::ODESolver
static MFEM_EXPORT std::string	ExplicitTypes
static MFEM_EXPORT std::string	ImplicitTypes
static MFEM_EXPORT std::string	Types
Protected Member Functions inherited from mfem::SundialsSolver
bool	Parallel () const
bool	Parallel () const
	SundialsSolver ()
	Protected constructor: objects of this type should be constructed only as part of a derived class.
void	AllocateEmptyNVector (N_Vector &y)
void	AllocateEmptyNVector (N_Vector &y, MPI_Comm comm)
Static Protected Attributes inherited from mfem::SundialsSolver
static constexpr double	default_rel_tol = 1e-4
	Default scalar relative tolerance.
static constexpr double	default_abs_tol = 1e-9
	Default scalar absolute tolerance.

Detailed Description

Interface to the CVODE library – linear multi-step methods.

Definition at line 419 of file sundials.hpp.

Member Typedef Documentation

EWTFunction

typedef std::function<int(Vector y, Vector w, CVODESolver*)> mfem::CVODESolver::EWTFunction

protected

Typedef declaration for error weight functions.

Definition at line 452 of file sundials.hpp.

RootFunction

typedef std::function<int(sunrealtype t, Vector y, Vector gout, CVODESolver *)> mfem::CVODESolver::RootFunction

protected

Typedef for root finding functions.

Definition at line 446 of file sundials.hpp.

Constructor & Destructor Documentation

CVODESolver() [1/2]

mfem::CVODESolver::CVODESolver

(

int

lmm

)

Construct a serial wrapper to SUNDIALS' CVODE integrator.

Parameters

[in]

lmm

Specifies the linear multistep method, the options are: CV_ADAMS - implicit methods for non-stiff systems, CV_BDF - implicit methods for stiff systems.

Definition at line 721 of file sundials.cpp.

CVODESolver() [2/2]

mfem::CVODESolver::CVODESolver	(	MPI_Comm	comm,
		int	lmm )

Construct a parallel wrapper to SUNDIALS' CVODE integrator.

Parameters

[in]	comm	The MPI communicator used to partition the ODE system
[in]	lmm	Specifies the linear multistep method, the options are: CV_ADAMS - implicit methods for non-stiff systems, CV_BDF - implicit methods for stiff systems.

Definition at line 728 of file sundials.cpp.

~CVODESolver()

mfem::CVODESolver::~CVODESolver ( )

virtual

Destroy the associated CVODE memory and SUNDIALS objects.

Definition at line 990 of file sundials.cpp.

Member Function Documentation

GetNumSteps()

long mfem::CVODESolver::GetNumSteps

(

)

Get the number of internal steps taken so far.

Definition at line 931 of file sundials.cpp.

Init()

void mfem::CVODESolver::Init ( TimeDependentOperator & f_ )

overridevirtual

Initialize CVODE: calls CVodeCreate() to create the CVODE memory and set some defaults.

If the CVODE memory has already been created, it checks if the problem size has changed since the last call to Init(). If the problem is the same then CVodeReInit() will be called in the next call to Step(). If the problem size has changed, the CVODE memory is freed and realloced for the new problem size.

Parameters

[in]

f_

The TimeDependentOperator that defines the ODE system.

Note

All other methods must be called after Init().

If this method is called a second time with a different problem size, then any non-default user-set options will be lost and will need to be set again.

Reimplemented from mfem::ODESolver.

Definition at line 735 of file sundials.cpp.

LinSysSetup()

int mfem::CVODESolver::LinSysSetup ( sunrealtype t, N_Vector y, N_Vector fy, SUNMatrix A, sunbooleantype jok, sunbooleantype * jcur, sunrealtype gamma, void * user_data, N_Vector tmp1, N_Vector tmp2, N_Vector tmp3 )

staticprotected

Setup the linear system \( A x = b \).

Definition at line 696 of file sundials.cpp.

LinSysSolve()

int mfem::CVODESolver::LinSysSolve ( SUNLinearSolver LS, SUNMatrix A, N_Vector x, N_Vector b, sunrealtype tol )

staticprotected

Solve the linear system \( A x = b \).

Definition at line 711 of file sundials.cpp.

PrintInfo()

void mfem::CVODESolver::PrintInfo

(

)

const

Print various CVODE statistics.

Definition at line 945 of file sundials.cpp.

RHS()

int mfem::CVODESolver::RHS ( sunrealtype t, const N_Vector y, N_Vector ydot, void * user_data )

staticprotected

Number of components in gout.

Wrapper to compute the ODE rhs function.

Definition at line 658 of file sundials.cpp.

root()

int mfem::CVODESolver::root ( sunrealtype t, N_Vector y, sunrealtype * gout, void * user_data )

staticprotected

Prototype to define root finding for CVODE.

Definition at line 675 of file sundials.cpp.

SetMaxNSteps()

void mfem::CVODESolver::SetMaxNSteps

(

int

steps

)

Set the maximum number of time steps.

Definition at line 925 of file sundials.cpp.

SetMaxOrder()

void mfem::CVODESolver::SetMaxOrder

(

int

max_order

)

Set the maximum method order.

CVODE uses adaptive-order integration, based on the local truncation error. The default values for max_order are 12 for CV_ADAMS and 5 for CV_BDF. Use this if you know a priori that your system is such that higher order integration formulas are unstable.

Note

max_order can't be higher than the current maximum order.

Definition at line 939 of file sundials.cpp.

SetMaxStep()

void mfem::CVODESolver::SetMaxStep

(

double

dt_max

)

Set the maximum time step.

Definition at line 919 of file sundials.cpp.

SetRootFinder()

void mfem::CVODESolver::SetRootFinder	(	int	components,
		RootFunction	func )

Initialize Root Finder.

Definition at line 688 of file sundials.cpp.

SetSStolerances()

void mfem::CVODESolver::SetSStolerances	(	double	reltol,
		double	abstol )

Set the scalar relative and scalar absolute tolerances.

Definition at line 901 of file sundials.cpp.

SetStepMode()

void mfem::CVODESolver::SetStepMode

(

int

itask

)

Select the CVODE step mode: CV_NORMAL (default) or CV_ONE_STEP.

Parameters

[in]

itask

The desired step mode.

Definition at line 896 of file sundials.cpp.

SetSVtolerances()

void mfem::CVODESolver::SetSVtolerances	(	double	reltol,
		Vector	abstol )

Set the scalar relative and vector of absolute tolerances.

Definition at line 907 of file sundials.cpp.

Step()

void mfem::CVODESolver::Step ( Vector & x, double & t, double & dt )

override

Integrate the ODE with CVODE using the specified step mode.

Parameters

[in,out]	x	On output, the solution vector at the requested output time tout = t + dt.
[in,out]	t	On output, the output time reached.
[in,out]	dt	On output, the last time step taken.

Note

On input, the values of t and dt are used to compute desired output time for the integration, tout = t + dt.

Definition at line 823 of file sundials.cpp.

UseMFEMLinearSolver()

void mfem::CVODESolver::UseMFEMLinearSolver

(

)

Attach the linear system setup and solve methods from the TimeDependentOperator i.e., SUNImplicitSetup() and SUNImplicitSolve() to CVODE.

Definition at line 850 of file sundials.cpp.

UseSundialsLinearSolver()

void mfem::CVODESolver::UseSundialsLinearSolver

(

)

Attach SUNDIALS GMRES linear solver to CVODE.

Definition at line 881 of file sundials.cpp.

Member Data Documentation

ewt_func

EWTFunction mfem::CVODESolver::ewt_func

protected

A class member to facilitate pointing to a user-specified error weight function.

Definition at line 456 of file sundials.hpp.

lmm_type

int mfem::CVODESolver::lmm_type

protected

Linear multistep method type.

Definition at line 422 of file sundials.hpp.

root_components

int mfem::CVODESolver::root_components

protected

Definition at line 424 of file sundials.hpp.

root_func

RootFunction mfem::CVODESolver::root_func

protected

A class member to facilitate pointing to a user-specified root function.

Definition at line 449 of file sundials.hpp.

step_mode

int mfem::CVODESolver::step_mode

protected

CVODE step mode (CV_NORMAL or CV_ONE_STEP).

Definition at line 423 of file sundials.hpp.

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

• linalg/sundials.hpp
• linalg/sundials.cpp