The Incomplete Cholesky (IC) preconditioner solves the equation $LL^H*x = b$ for a given lower triangular matrix L and the right hand side b (can contain multiple right hand sides). More...

#include <ginkgo/core/preconditioner/ic.hpp>

Inheritance diagram for gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >:

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Collaboration diagram for gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >:

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Classes
class	Factory

struct	parameters_type

Public Types
using	l_solver_type = std::conditional_t< gko::detail::is_ginkgo_linop< LSolverTypeOrValueType >, LSolverTypeOrValueType, LinOp >

using	value_type = gko::detail::get_value_type< LSolverTypeOrValueType >

using	lh_solver_type = gko::detail::transposed_type< l_solver_type >

using	index_type = IndexType

using	transposed_type = Ic< LSolverTypeOrValueType, IndexType >

Public Types inherited from gko::EnablePolymorphicAssignment< Ic< LSolverTypeOrValueType, IndexType > >
using	result_type = Ic< LSolverTypeOrValueType, IndexType >

Public Types inherited from gko::ConvertibleTo< Ic< LSolverTypeOrValueType, IndexType > >
using	result_type = Ic< LSolverTypeOrValueType, IndexType >

Public Member Functions
const parameters_type &	get_parameters () const

std::shared_ptr< const l_solver_type >	get_l_solver () const
	Returns the solver which is used for the provided L matrix. More...

std::shared_ptr< const lh_solver_type >	get_lh_solver () const
	Returns the solver which is used for the L^H matrix. More...

std::unique_ptr< LinOp >	transpose () const override
	Returns a LinOp representing the transpose of the Transposable object. More...

std::unique_ptr< LinOp >	conj_transpose () const override
	Returns a LinOp representing the conjugate transpose of the Transposable object. More...

Ic &	operator= (const Ic &other)
	Copy-assigns an IC preconditioner. More...

Ic &	operator= (Ic &&other)
	Move-assigns an IC preconditioner. More...

	Ic (const Ic &other)
	Copy-constructs an IC preconditioner. More...

	Ic (Ic &&other)
	Move-constructs an IC preconditioner. More...

Public Member Functions inherited from gko::EnableLinOp< Ic< LSolverTypeOrValueType, IndexType > >
const Ic< LSolverTypeOrValueType, IndexType > *	apply (ptr_param< const LinOp > b, ptr_param< LinOp > x) const

Ic< LSolverTypeOrValueType, IndexType > *	apply (ptr_param< const LinOp > b, ptr_param< LinOp > x)

const Ic< LSolverTypeOrValueType, IndexType > *	apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x) const

Ic< LSolverTypeOrValueType, IndexType > *	apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x)

Public Member Functions inherited from gko::EnableAbstractPolymorphicObject< Ic< LSolverTypeOrValueType, IndexType >, LinOp >
std::unique_ptr< Ic< LSolverTypeOrValueType, IndexType > >	create_default (std::shared_ptr< const Executor > exec) const

std::unique_ptr< Ic< LSolverTypeOrValueType, IndexType > >	create_default () const

std::unique_ptr< Ic< LSolverTypeOrValueType, IndexType > >	clone (std::shared_ptr< const Executor > exec) const

std::unique_ptr< Ic< LSolverTypeOrValueType, IndexType > >	clone () const

Ic< LSolverTypeOrValueType, IndexType > *	copy_from (const PolymorphicObject *other)

std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, Ic< LSolverTypeOrValueType, IndexType > > *	copy_from (std::unique_ptr< Derived > &&other)

std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, Ic< LSolverTypeOrValueType, IndexType > > *	copy_from (const std::unique_ptr< Derived > &other)

Ic< LSolverTypeOrValueType, IndexType > *	copy_from (const std::shared_ptr< const PolymorphicObject > &other)

Ic< LSolverTypeOrValueType, IndexType > *	move_from (ptr_param< PolymorphicObject > other)

Ic< LSolverTypeOrValueType, IndexType > *	clear ()

Public Member Functions inherited from gko::LinOp
LinOp *	apply (ptr_param< const LinOp > b, ptr_param< LinOp > x)
	Applies a linear operator to a vector (or a sequence of vectors). More...

const LinOp *	apply (ptr_param< const LinOp > b, ptr_param< LinOp > x) const

LinOp *	apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x)
	Performs the operation x = alpha * op(b) + beta * x. More...

const LinOp *	apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x) const

const dim< 2 > &	get_size () const noexcept
	Returns the size of the operator. More...

virtual bool	apply_uses_initial_guess () const
	Returns true if the linear operator uses the data given in x as an initial guess. More...

LinOp &	operator= (const LinOp &)=default
	Copy-assigns a LinOp. More...

LinOp &	operator= (LinOp &&other)
	Move-assigns a LinOp. More...

	LinOp (const LinOp &)=default
	Copy-constructs a LinOp. More...

	LinOp (LinOp &&other)
	Move-constructs a LinOp. More...

Public Member Functions inherited from gko::EnableAbstractPolymorphicObject< LinOp >
std::unique_ptr< LinOp >	create_default (std::shared_ptr< const Executor > exec) const

std::unique_ptr< LinOp >	create_default () const

std::unique_ptr< LinOp >	clone (std::shared_ptr< const Executor > exec) const

std::unique_ptr< LinOp >	clone () const

LinOp *	copy_from (const PolymorphicObject *other)

std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, LinOp > *	copy_from (std::unique_ptr< Derived > &&other)

std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, LinOp > *	copy_from (const std::unique_ptr< Derived > &other)

LinOp *	copy_from (const std::shared_ptr< const PolymorphicObject > &other)

LinOp *	move_from (ptr_param< PolymorphicObject > other)

LinOp *	clear ()

Public Member Functions inherited from gko::PolymorphicObject
PolymorphicObject &	operator= (const PolymorphicObject &)

std::unique_ptr< PolymorphicObject >	create_default (std::shared_ptr< const Executor > exec) const
	Creates a new "default" object of the same dynamic type as this object. More...

std::unique_ptr< PolymorphicObject >	create_default () const
	Creates a new "default" object of the same dynamic type as this object. More...

std::unique_ptr< PolymorphicObject >	clone (std::shared_ptr< const Executor > exec) const
	Creates a clone of the object. More...

std::unique_ptr< PolymorphicObject >	clone () const
	Creates a clone of the object. More...

PolymorphicObject *	copy_from (const PolymorphicObject *other)
	Copies another object into this object. More...

template<typename Derived , typename Deleter >
std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, PolymorphicObject > *	copy_from (std::unique_ptr< Derived, Deleter > &&other)
	Moves another object into this object. More...

template<typename Derived , typename Deleter >
std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, PolymorphicObject > *	copy_from (const std::unique_ptr< Derived, Deleter > &other)
	Copies another object into this object. More...

PolymorphicObject *	copy_from (const std::shared_ptr< const PolymorphicObject > &other)
	Copies another object into this object. More...

PolymorphicObject *	move_from (ptr_param< PolymorphicObject > other)
	Moves another object into this object. More...

PolymorphicObject *	clear ()
	Transforms the object into its default state. More...

std::shared_ptr< const Executor >	get_executor () const noexcept
	Returns the Executor of the object. More...

Public Member Functions inherited from gko::log::EnableLogging< PolymorphicObject >
void	add_logger (std::shared_ptr< const Logger > logger) override

void	remove_logger (const Logger *logger) override

void	remove_logger (ptr_param< const Logger > logger)

const std::vector< std::shared_ptr< const Logger > > &	get_loggers () const override

void	clear_loggers () override

Public Member Functions inherited from gko::log::Loggable
void	remove_logger (ptr_param< const Logger > logger)

Public Member Functions inherited from gko::EnablePolymorphicAssignment< Ic< LSolverTypeOrValueType, IndexType > >
void	convert_to (result_type *result) const override
	Converts the implementer to an object of type result_type. More...

void	move_to (result_type *result) override
	Converts the implementer to an object of type result_type by moving data from this object. More...

Public Member Functions inherited from gko::ConvertibleTo< Ic< LSolverTypeOrValueType, IndexType > >
void	convert_to (ptr_param< result_type > result) const

void	move_to (ptr_param< result_type > result)

Static Public Member Functions
static auto	build () -> decltype(Factory ::create())

static parameters_type	parse (const config::pnode &config, const config::registry &context, const config::type_descriptor &td_for_child=config::make_type_descriptor< value_type, index_type >())
	Create the parameters from the property_tree. More...

Friends
class	EnableLinOp< Ic >

class	EnablePolymorphicObject< Ic, LinOp >

Detailed Description

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>
class gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >

The Incomplete Cholesky (IC) preconditioner solves the equation $LL^H*x = b$ for a given lower triangular matrix L and the right hand side b (can contain multiple right hand sides).

It allows to set both the solver for L defaulting to solver::LowerTrs, which is a direct triangular solvers. The solver for L^H is the conjugate-transposed solver for L, ensuring that the preconditioner is symmetric and positive-definite. For this L solver, a factory can be provided (using with_l_solver) to have more control over their behavior. In particular, it is possible to use an iterative method for solving the triangular systems. The default parameters for an iterative triangluar solver are:

reduction factor = 1e-4
max iteration = <number of="" rows="" of="" the="" matrix="" given="" to="" the="" solver>=""> Solvers without such criteria can also be used, in which case none are set.

An object of this class can be created with a matrix or a gko::Composition containing two matrices. If created with a matrix, it is factorized before creating the solver. If a gko::Composition (containing two matrices) is used, the first operand will be taken as the L matrix, the second will be considered the L^H matrix, which helps to avoid the otherwise necessary transposition of L inside the solver. ParIc can be directly used, since it orders the factors in the correct way.

Note: When providing a gko::Composition, the first matrix must be the lower matrix ( ), and the second matrix must be its conjugate-transpose ( ). If they are swapped, solving might crash or return the wrong result.; Do not use symmetric solvers (like CG) for the L solver since both matrices (L and L^H) are, by design, not symmetric.; This class is not thread safe (even a const object is not) because it uses an internal cache to accelerate multiple (sequential) applies. Using it in parallel can lead to segmentation faults, wrong results and other unwanted behavior.; The default template during parse is <ValueType, IndexType> not <LowerTrs, IndexType>. Only the variants with ValueType are supported in parse.

Template Parameters

LSolverTypeOrValueType	type of the solver or the value type used for the L matrix. Defaults to solver::LowerTrs
IndexType	type of the indices when ParIc is used to generate the L and L^H factors. Irrelevant otherwise.

Constructor & Destructor Documentation

◆ Ic() [1/2]

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>

gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::Ic ( const Ic< LSolverTypeOrValueType, IndexType > & other )

inline

Copy-constructs an IC preconditioner.

Inherits the executor, shallow-copies the solvers and parameters.

References gko::PolymorphicObject::get_executor().

◆ Ic() [2/2]

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>

gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::Ic ( Ic< LSolverTypeOrValueType, IndexType > && other )

inline

Move-constructs an IC preconditioner.

Inherits the executor, moves the solvers and parameters. The moved-from object is empty (0x0 with nullptr solvers and default parameters)

References gko::PolymorphicObject::get_executor().

Member Function Documentation

◆ conj_transpose()

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>

std::unique_ptr<LinOp> gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::conj_transpose ( ) const

inlineoverridevirtual

Returns a LinOp representing the conjugate transpose of the Transposable object.

Returns: a pointer to the new conjugate transposed object

Implements gko::Transposable.

References gko::as(), gko::PolymorphicObject::get_executor(), gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::get_l_solver(), gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::get_lh_solver(), gko::LinOp::get_size(), gko::share(), and gko::transpose().

◆ get_l_solver()

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>

std::shared_ptr<const l_solver_type> gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::get_l_solver ( ) const

inline

Returns the solver which is used for the provided L matrix.

Returns: the solver which is used for the provided L matrix

Referenced by gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::conj_transpose(), and gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::transpose().

◆ get_lh_solver()

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>

std::shared_ptr<const lh_solver_type> gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::get_lh_solver ( ) const

inline

Returns the solver which is used for the L^H matrix.

Returns: the solver which is used for the L^H matrix

Referenced by gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::conj_transpose(), and gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::transpose().

◆ operator=() [1/2]

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>

Ic& gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::operator= ( const Ic< LSolverTypeOrValueType, IndexType > & other )

inline

Copy-assigns an IC preconditioner.

Preserves the executor, shallow-copies the solvers and parameters. Creates a clone of the solvers if they are on the wrong executor.

References gko::clone(), and gko::PolymorphicObject::get_executor().

◆ operator=() [2/2]

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>

Ic& gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::operator= ( Ic< LSolverTypeOrValueType, IndexType > && other )

inline

Move-assigns an IC preconditioner.

Preserves the executor, moves the solvers and parameters. Creates a clone of the solvers if they are on the wrong executor. The moved-from object is empty (0x0 with nullptr solvers and default parameters)

References gko::clone(), and gko::PolymorphicObject::get_executor().

◆ parse()

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>

static parameters_type gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::parse	(	const config::pnode &	config,
		const config::registry &	context,
		const config::type_descriptor &	td_for_child = `config::make_type_descriptor<value_type, index_type>()`
	)

inlinestatic

Create the parameters from the property_tree.

Because this is directly tied to the specific type, the value/index type settings within config are ignored and type_descriptor is only used for children configs.

Parameters

config	the property tree for setting
context	the registry
td_for_child	the type descriptor for children configs. The default uses the value/index type of this class. When l_solver_type uses LinOp not concrete type, it will use the default_precision in ginkgo.

Returns: parameters

Note: only support the following when using <ValueType, IndexType> not <LSolverType, IndexType> variants

◆ transpose()

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>

std::unique_ptr<LinOp> gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::transpose ( ) const

inlineoverridevirtual

Returns a LinOp representing the transpose of the Transposable object.

Returns: a pointer to the new transposed object

Implements gko::Transposable.

References gko::as(), gko::PolymorphicObject::get_executor(), gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::get_l_solver(), gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >::get_lh_solver(), gko::LinOp::get_size(), gko::share(), and gko::transpose().

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

ginkgo/core/preconditioner/ic.hpp

Classes

Public Types

Public Member Functions

Static Public Member Functions

Friends

Detailed Description

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32> class gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >

Constructor & Destructor Documentation

◆ Ic() [1/2]

◆ Ic() [2/2]

Member Function Documentation

◆ conj_transpose()

◆ get_l_solver()

◆ get_lh_solver()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ parse()

◆ transpose()

template<typename LSolverTypeOrValueType = solver::LowerTrs<>, typename IndexType = int32>
class gko::preconditioner::Ic< LSolverTypeOrValueType, IndexType >