PETScWrappers::PreconditionLU Class Reference

#include <deal.II/lac/petsc_precondition.h>

Inheritance diagram for PETScWrappers::PreconditionLU:

Classes
struct	AdditionalData

Public Member Functions
	PreconditionLU ()
	PreconditionLU (const MatrixBase &matrix, const AdditionalData &additional_data=AdditionalData())
void	initialize (const MatrixBase &matrix, const AdditionalData &additional_data=AdditionalData())
void	clear ()
void	vmult (VectorBase &dst, const VectorBase &src) const
void	Tvmult (VectorBase &dst, const VectorBase &src) const
void	setup ()
const PC &	get_pc () const
MPI_Comm	get_mpi_communicator () const
template<class Archive >
void	serialize (Archive &ar, const unsigned int version)
EnableObserverPointer functionality
Classes derived from EnableObserverPointer provide a facility to subscribe to this object. This is mostly used by the ObserverPointer class.
void	subscribe (std::atomic< bool > *const validity, const std::string &identifier="") const
void	unsubscribe (std::atomic< bool > *const validity, const std::string &identifier="") const
unsigned int	n_subscriptions () const
template<typename StreamType >
void	list_subscribers (StreamType &stream) const
void	list_subscribers () const

Static Public Member Functions
static ::ExceptionBase &	ExcInUse (int arg1, std::string arg2, std::string arg3)
static ::ExceptionBase &	ExcNoSubscriber (std::string arg1, std::string arg2)

Protected Member Functions
void	create_pc_with_mat (const MatrixBase &)
void	create_pc_with_comm (const MPI_Comm)

Protected Attributes
AdditionalData	additional_data
PC	pc

Private Types
using	map_value_type = decltype(counter_map)::value_type
using	map_iterator = decltype(counter_map)::iterator

Private Member Functions
void	check_no_subscribers () const noexcept

Private Attributes
std::atomic< unsigned int >	counter
std::map< std::string, unsigned int >	counter_map
std::vector< std::atomic< bool > * >	validity_pointers
const std::type_info *	object_info

Static Private Attributes
static std::mutex	mutex

Detailed Description

A class that implements the interface to use the PETSc LU preconditioner (PCLU). Unlike classes like PreconditionILU, this class usually (depending on the settings) performs an exact factorization of the matrix, so it is not necessary to wrap it in an iterative solver. This class is typically used with SolverPreOnly to get a direct solver. Alternatively, you can use PreconditionBase::vmult() directly.

Note

This is not a parallel preconditioner so it only works in serial computations with a single processor.

Definition at line 541 of file petsc_precondition.h.

Member Typedef Documentation

map_value_type

using EnableObserverPointer::map_value_type = decltype(counter_map)::value_type

privateinherited

The data type used in counter_map.

Definition at line 238 of file enable_observer_pointer.h.

map_iterator

using EnableObserverPointer::map_iterator = decltype(counter_map)::iterator

privateinherited

The iterator type used in counter_map.

Definition at line 243 of file enable_observer_pointer.h.

Constructor & Destructor Documentation

PreconditionLU() [1/2]

PreconditionLU< number >::PreconditionLU

(

)

Empty Constructor. You need to call initialize() before using this object.

Definition at line 864 of file petsc_precondition.cc.

PreconditionLU() [2/2]

PreconditionLU< number >::PreconditionLU	(	const MatrixBase &	matrix,
		const AdditionalData &	additional_data = AdditionalData()
	)

Constructor. Take the matrix which is used to form the preconditioner, and additional flags if there are any.

Definition at line 870 of file petsc_precondition.cc.

Member Function Documentation

initialize()

void PreconditionLU< number >::initialize	(	const MatrixBase &	matrix,
		const AdditionalData &	additional_data = AdditionalData()
	)

Initialize the preconditioner object and calculate all data that is necessary for applying it in a solver. This function is automatically called when calling the constructor with the same arguments and is only used if you create the preconditioner without arguments.

Definition at line 879 of file petsc_precondition.cc.

clear()

void PETScWrappers::PreconditionBase::clear ( )

inherited

Destroys the preconditioner, leaving an object like just after having called the default constructor.

Definition at line 56 of file petsc_precondition.cc.

vmult()

void PETScWrappers::PreconditionBase::vmult ( VectorBase &  dst, const VectorBase &  src  ) const

inherited

Apply the preconditioner once to the given src vector.

Definition at line 66 of file petsc_precondition.cc.

Tvmult()

void PETScWrappers::PreconditionBase::Tvmult ( VectorBase &  dst, const VectorBase &  src  ) const

inherited

Apply the transpose preconditioner once to the given src vector.

Definition at line 75 of file petsc_precondition.cc.

setup()

void PETScWrappers::PreconditionBase::setup ( )

inherited

Explicitly call setup. This is usually not needed since PETSc will automatically call the setup function when needed.

Definition at line 84 of file petsc_precondition.cc.

get_pc()

const PC & PETScWrappers::PreconditionBase::get_pc ( ) const

inherited

Give access to the underlying PETSc object.

Definition at line 125 of file petsc_precondition.cc.

get_mpi_communicator()

MPI_Comm PETScWrappers::PreconditionBase::get_mpi_communicator ( ) const

inherited

Return the underlying MPI communicator.

Definition at line 93 of file petsc_precondition.cc.

create_pc_with_mat()

void PETScWrappers::PreconditionBase::create_pc_with_mat ( const MatrixBase &  matrix )

protectedinherited

Internal function to create the PETSc preconditioner object. Fails if called twice.

Definition at line 99 of file petsc_precondition.cc.

create_pc_with_comm()

void PETScWrappers::PreconditionBase::create_pc_with_comm ( const MPI_Comm  comm )

protectedinherited

Internal function to create the PETSc preconditioner object.

Definition at line 117 of file petsc_precondition.cc.

subscribe()

void EnableObserverPointer::subscribe ( std::atomic< bool > *const  validity, const std::string &  identifier = ""  ) const

inherited

Subscribes a user of the object by storing the pointer validity. The subscriber may be identified by text supplied as identifier.

Definition at line 131 of file enable_observer_pointer.cc.

unsubscribe()

void EnableObserverPointer::unsubscribe ( std::atomic< bool > *const  validity, const std::string &  identifier = ""  ) const

inherited

Unsubscribes a user from the object.

Note

The identifier and the validity pointer must be the same as the one supplied to subscribe().

Definition at line 151 of file enable_observer_pointer.cc.

n_subscriptions()

unsigned int EnableObserverPointer::n_subscriptions ( ) const

inlineinherited

Return the present number of subscriptions to this object. This allows to use this class for reference counted lifetime determination where the last one to unsubscribe also deletes the object.

Definition at line 322 of file enable_observer_pointer.h.

list_subscribers() [1/2]

template<typename StreamType >

void EnableObserverPointer::list_subscribers ( StreamType &  stream ) const

inlineinherited

List the subscribers to the input stream.

Definition at line 339 of file enable_observer_pointer.h.

list_subscribers() [2/2]

void EnableObserverPointer::list_subscribers ( ) const

inherited

List the subscribers to deallog.

Definition at line 199 of file enable_observer_pointer.cc.

serialize()

template<class Archive >

void EnableObserverPointer::serialize ( Archive &  ar, const unsigned int  version  )

inlineinherited

Read or write the data of this object to or from a stream for the purpose of serialization using the BOOST serialization library.

This function does not actually serialize any of the member variables of this class. The reason is that what this class stores is only who subscribes to this object, but who does so at the time of storing the contents of this object does not necessarily have anything to do with who subscribes to the object when it is restored. Consequently, we do not want to overwrite the subscribers at the time of restoring, and then there is no reason to write the subscribers out in the first place.

Definition at line 331 of file enable_observer_pointer.h.

check_no_subscribers()

void EnableObserverPointer::check_no_subscribers ( ) const

privatenoexceptinherited

Check that there are no objects subscribing to this object. If this check passes then it is safe to destroy the current object. It this check fails then this function will either abort or print an error message to deallog (by using the AssertNothrow mechanism), but will not throw an exception.

Note

Since this function is just a consistency check it does nothing in release mode.

If this function is called when there is an uncaught exception then, rather than aborting, this function prints an error message to the standard error stream and returns.

Definition at line 53 of file enable_observer_pointer.cc.

Member Data Documentation

additional_data

AdditionalData PETScWrappers::PreconditionLU::additional_data

protected

Store a copy of the flags for this particular preconditioner.

Definition at line 605 of file petsc_precondition.h.

pc

PC PETScWrappers::PreconditionBase::pc

protectedinherited

The PETSc preconditioner object

Definition at line 120 of file petsc_precondition.h.

counter

std::atomic<unsigned int> EnableObserverPointer::counter

mutableprivateinherited

Store the number of objects which subscribed to this object. Initially, this number is zero, and upon destruction it shall be zero again (i.e. all objects which subscribed should have unsubscribed again).

The creator (and owner) of an object is counted in the map below if HE manages to supply identification.

We use the mutable keyword in order to allow subscription to constant objects also.

This counter may be read from and written to concurrently in multithreaded code: hence we use the std::atomic class template.

Definition at line 227 of file enable_observer_pointer.h.

counter_map

std::map<std::string, unsigned int> EnableObserverPointer::counter_map

mutableprivateinherited

In this map, we count subscriptions for each different identification string supplied to subscribe().

Definition at line 233 of file enable_observer_pointer.h.

validity_pointers

std::vector<std::atomic<bool> *> EnableObserverPointer::validity_pointers

mutableprivateinherited

In this vector, we store pointers to the validity bool in the ObserverPointer objects that subscribe to this class.

Definition at line 249 of file enable_observer_pointer.h.

object_info

const std::type_info* EnableObserverPointer::object_info

mutableprivateinherited

Pointer to the typeinfo object of this object, from which we can later deduce the class name. Since this information on the derived class is neither available in the destructor, nor in the constructor, we obtain it in between and store it here.

Definition at line 257 of file enable_observer_pointer.h.

mutex

std::mutex EnableObserverPointer::mutex

staticprivateinherited

A mutex used to ensure data consistency when accessing the mutable members of this class. This lock is used in the subscribe() and unsubscribe() functions, as well as in list_subscribers().

Definition at line 280 of file enable_observer_pointer.h.

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

• include/deal.II/lac/petsc_precondition.h
• source/lac/petsc_precondition.cc