gko::matrix::Identity< ValueType > Class Template Reference

This class is a utility which efficiently implements the identity matrix (a linear operator which maps each vector to itself). More...

#include <ginkgo/core/matrix/identity.hpp>

Inheritance diagram for gko::matrix::Identity< ValueType >:

Collaboration diagram for gko::matrix::Identity< ValueType >:

Public Types
using	value_type = ValueType
using	transposed_type = Identity< ValueType >
Public Types inherited from gko::EnableCloneable< Identity< ValueType > >
using	result_type = Identity< ValueType >
Public Types inherited from gko::ConvertibleTo< ResultType >
using	result_type = ResultType

Public Member Functions
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...
Public Member Functions inherited from gko::LinOp
void	apply (ptr_param< const LinOp > b, ptr_param< LinOp > x) const
	Applies a linear operator to a vector (or a sequence of vectors). More...
void	apply (ptr_param< const LinOp > alpha, ptr_param< const LinOp > b, ptr_param< const LinOp > beta, ptr_param< LinOp > x) const
	Performs the operation x = alpha * op(b) + beta * x. More...
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::PolymorphicObject
PolymorphicObject &	operator= (const PolymorphicObject &)
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::EnableCloneable< Identity< ValueType > >
std::unique_ptr< Identity< ValueType > >	clone (std::shared_ptr< const Executor > exec) const
	Creates a clone of the object. More...
std::unique_ptr< Identity< ValueType > >	clone () const
	Creates a clone of the object. More...
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...
std::unique_ptr< Identity< ValueType > >	create_default () const
std::unique_ptr< Identity< ValueType > >	create_default (std::shared_ptr< const Executor > exec) const
Public Member Functions inherited from gko::ConvertibleTo< ResultType >
void	convert_to (ptr_param< result_type > result) const
void	move_to (ptr_param< result_type > result)
Public Member Functions inherited from gko::Cloneable
std::unique_ptr< Cloneable >	clone (std::shared_ptr< const Executor > exec) const
std::unique_ptr< Cloneable >	clone () const
Cloneable *	copy_from (ptr_param< const Cloneable > other)
Cloneable *	move_from (ptr_param< Cloneable > other)
std::unique_ptr< Cloneable >	create_default (std::shared_ptr< const Executor > exec) const
std::unique_ptr< Cloneable >	create_default () const

Static Public Member Functions
static std::unique_ptr< Identity >	create (std::shared_ptr< const Executor > exec, dim< 2 > size)
	Creates an Identity matrix of the specified size. More...
static std::unique_ptr< Identity >	create (std::shared_ptr< const Executor > exec, size_type size=0)
	Creates an Identity matrix of the specified size. More...

Friends
class	EnableCloneable< Identity >

Detailed Description

template<typename ValueType = default_precision>
class gko::matrix::Identity< ValueType >

This class is a utility which efficiently implements the identity matrix (a linear operator which maps each vector to itself).

Thus, objects of the Identity class always represent a square matrix, and don't require any storage for their values. The apply method is implemented as a simple copy (or a linear combination).

Note

This class is useful when composing it with other operators. For example, it can be used instead of a preconditioner in Krylov solvers, if one wants to run a "plain" solver, without using a preconditioner.

Template Parameters

ValueType

precision of matrix elements

Member Function Documentation

conj_transpose()

template<typename ValueType = default_precision>

std::unique_ptr<LinOp> gko::matrix::Identity< ValueType >::conj_transpose ( ) const

overridevirtual

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

Returns

a pointer to the new conjugate transposed object

Implements gko::Transposable.

create() [1/2]

template<typename ValueType = default_precision>

static std::unique_ptr<Identity> gko::matrix::Identity< ValueType >::create ( std::shared_ptr< const Executor >  exec, dim< 2 >  size  )

static

Creates an Identity matrix of the specified size.

Parameters

size	size of the matrix (must be square)

create() [2/2]

template<typename ValueType = default_precision>

static std::unique_ptr<Identity> gko::matrix::Identity< ValueType >::create ( std::shared_ptr< const Executor >  exec, size_type  size = 0  )

static

Creates an Identity matrix of the specified size.

Parameters

size	size of the matrix

transpose()

template<typename ValueType = default_precision>

std::unique_ptr<LinOp> gko::matrix::Identity< ValueType >::transpose ( ) const

overridevirtual

Returns a LinOp representing the transpose of the Transposable object.

Returns

a pointer to the new transposed object

Implements gko::Transposable.

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

• ginkgo/core/matrix/identity.hpp