Linear system solver using GMRES. More...

#include <ptems/solvers/gmres.hpp>

Inheritance diagram for ptems::GMRESSolver< T >:

Collaboration diagram for ptems::GMRESSolver< T >:

Public Types
typedef remove_complex_t< T >	real_type
	The real valued type the solver is for (either T, or R for T=std:complex<R>) More...

typedef T	value_type
	Defines the type of a matrix entry in the linear system. More...

typedef Ref	reference
	Defines the type of a reference to a matrix entry in the linear system. More...

typedef ConstRef	const_reference
	Defines the type of a const reference to a matrix entry in the linear system. More...

typedef std::optional< typename detail::ReferenceWrapper< reference >::type >	optional_reference
	Defines the type of a reference to a matrix entry in the linear system. More...

typedef std::optional< typename detail::ReferenceWrapper< const_reference >::type >	optional_const_reference
	Defines the type of a const reference to a matrix entry in the linear system. More...

Public Member Functions
	GMRESSolver (const ParallelComm &comm, const SparsityPattern &mat, std::size_t size, real_type tolerance, std::size_t maxItns, bool updateInitialGuess=false)
	Constructs a GMRES solver, without preconditioner, for a sparse matrix. More...

	GMRESSolver (const ParallelComm &comm, const SparsityPattern &mat, std::size_t size, const PPreconditioner< T > &preconditioner, real_type tolerance, std::size_t maxItns, bool updateInitialGuess=false)
	Constructs a GMRES solver for a sparse matrix. More...

const T &	InitialGuess (std::size_t i) const
	Returns a const reference to the specified entry of the initial guess. More...

T &	InitialGuess (std::size_t i)
	Returns a mutable reference to the specified entry of the initial guess. More...

void	FillInitialGuess (T value)
	Fills the initial guess vector with a constant. More...

template<typename It >
void	FillInitialGuess (It begin, It end)
	Fills the initial guess vector with the values from the specified iterator range. More...

virtual bool	DistributedConstruction () const override
	Gets if the matrix and right hand side should be constructed distributed (for MPI) More...

virtual LinearSolver< T >::optional_reference	Entry (std::size_t i, std::size_t j) override
	Gets a reference to the specified matrix entry. More...

virtual LinearSolver< T >::optional_const_reference	Entry (std::size_t i, std::size_t j) const override
	Gets a const reference to the specified matrix entry. More...

virtual void	Clear () override
	Clear the matrix of the linear system. More...

std::size_t	size () const override
	Gets the size of the linear system. More...

virtual std::vector< T >	Solve (const std::vector< T > &rhs, std::size_t offsetRHS=0, std::size_t lenRHS=-1) override
	Solves the linear system with the specified right-hand side. More...

virtual reference	operator() (std::size_t i, std::size_t j)
	Gets a reference to the specified matrix entry. More...

virtual const_reference	operator() (std::size_t i, std::size_t j) const
	Gets a const reference to the specified matrix entry. More...

virtual std::vector< T >	operator() (const std::vector< T > &rhs, std::size_t offsetRHS=0, std::size_t lenRHS=-1)
	Solves the linear system with the specified right-hand side. More...

Detailed Description

template<typename T>
class ptems::GMRESSolver< T >

Linear system solver using GMRES.

Todo:: Add restart?

Template Parameters

T	The type of the matrix entries

Member Typedef Documentation

◆ const_reference

template<typename T , typename Ref = T&, typename ConstRef = const T&>

typedef ConstRef ptems::LinearSolver< T, Ref, ConstRef >::const_reference

inherited

Defines the type of a const reference to a matrix entry in the linear system.

Can be a proxy object in some cases.

◆ optional_const_reference

template<typename T , typename Ref = T&, typename ConstRef = const T&>

typedef std::optional<typename detail::ReferenceWrapper<const_reference>::type> ptems::LinearSolver< T, Ref, ConstRef >::optional_const_reference

inherited

Defines the type of a const reference to a matrix entry in the linear system.

Can be a proxy object in some cases.

◆ optional_reference

template<typename T , typename Ref = T&, typename ConstRef = const T&>

typedef std::optional<typename detail::ReferenceWrapper<reference>::type> ptems::LinearSolver< T, Ref, ConstRef >::optional_reference

inherited

Defines the type of a reference to a matrix entry in the linear system.

Can be a proxy object in some cases.

◆ real_type

template<typename T >

typedef remove_complex_t<T> ptems::GMRESSolver< T >::real_type

The real valued type the solver is for (either T, or R for T=std:complex<R>)

◆ reference

template<typename T , typename Ref = T&, typename ConstRef = const T&>

typedef Ref ptems::LinearSolver< T, Ref, ConstRef >::reference

inherited

Defines the type of a reference to a matrix entry in the linear system.

Can be a proxy object in some cases.

◆ value_type

template<typename T , typename Ref = T&, typename ConstRef = const T&>

typedef T ptems::LinearSolver< T, Ref, ConstRef >::value_type

inherited

Defines the type of a matrix entry in the linear system.

Constructor & Destructor Documentation

◆ GMRESSolver() [1/2]

template<typename T >

ptems::GMRESSolver< T >::GMRESSolver	(	const ParallelComm &	comm,
		const SparsityPattern &	mat,
		std::size_t	size,
		real_type	tolerance,
		std::size_t	maxItns,
		bool	updateInitialGuess = `false`
	)

inline

Constructs a GMRES solver, without preconditioner, for a sparse matrix.

Parameters

comm	MPI communicator to use for construction and solving
mat	The sparsity pattern of the sparse matrix
size	The size of the linear system
tolerance	The desired tolerance for the GMRES iteration
maxItns	The maximum number of GMRES iterations to perform
updateInitialGuess	Specifies whether the initial guess should be updated with the solution of Solve. This is useful, for example, with nonlinear solvers as the initial guess for a linear solver at a nonlibnear iteration step will be the solution from the previous iteration of the nonlinear solver.

◆ GMRESSolver() [2/2]

template<typename T >

ptems::GMRESSolver< T >::GMRESSolver	(	const ParallelComm &	comm,
		const SparsityPattern &	mat,
		std::size_t	size,
		const PPreconditioner< T > &	preconditioner,
		real_type	tolerance,
		std::size_t	maxItns,
		bool	updateInitialGuess = `false`
	)

inline

Constructs a GMRES solver for a sparse matrix.

Parameters

comm	MPI communicator to use for construction and solving
mat	The sparsity pattern of the sparse matrix
size	The size of the linear system
preconditioner	The preconditioner to use at each step of the GMRES iteration. Can be null to use without preconditioner
tolerance	The desired tolerance for the GMRES iteration
maxItns	The maximum number of GMRES iterations to perform
updateInitialGuess	Specifies whether the initial guess should be updated with the solution of Solve. This is useful, for example, with nonlinear solvers as the initial guess for a linear solver at a nonlibnear iteration step will be the solution from the previous iteration of the nonlinear solver.

Member Function Documentation

◆ Clear()

template<typename T >

virtual void ptems::GMRESSolver< T >::Clear ( )

inlineoverridevirtual

Clear the matrix of the linear system.

Implements ptems::LinearSolver< T, Ref, ConstRef >.

◆ DistributedConstruction()

template<typename T >

virtual bool ptems::GMRESSolver< T >::DistributedConstruction ( ) const

inlineoverridevirtual

Gets if the matrix and right hand side should be constructed distributed (for MPI)

Returns: true yo distribute construction across processes, false otherwise

Implements ptems::LinearSolver< T, Ref, ConstRef >.

◆ Entry() [1/2]

template<typename T >

virtual LinearSolver<T>::optional_const_reference ptems::GMRESSolver< T >::Entry	(	std::size_t	i,
		std::size_t	j
	)		const

inlineoverridevirtual

Gets a const reference to the specified matrix entry.

Exceptions

std::out_of_range If the row or column index are not less than the linear system size

Parameters

i	The row index
j	The column index

Returns: A const reference to the element if its a non-zero entry, or an empty optional if the entry is a zero entry in the sparse matrix

Implements ptems::LinearSolver< T, Ref, ConstRef >.

◆ Entry() [2/2]

template<typename T >

virtual LinearSolver<T>::optional_reference ptems::GMRESSolver< T >::Entry	(	std::size_t	i,
		std::size_t	j
	)

inlineoverridevirtual

Gets a reference to the specified matrix entry.

Exceptions

std::out_of_range If the row or column index are not less than the linear system size

Parameters

i	The row index
j	The column index

Returns: A reference to the element if its a non-zero entry, or an empty optional if the entry is a zero entry in the sparse matrix

Implements ptems::LinearSolver< T, Ref, ConstRef >.

◆ FillInitialGuess() [1/2]

template<typename T >

template<typename It >

void ptems::GMRESSolver< T >::FillInitialGuess	(	It	begin,
		It	end
	)

inline

Fills the initial guess vector with the values from the specified iterator range.

Exceptions

std::invalid_argument If the size of the specified range is different to the size of the initial guess vector. If this exception is thrown some values WILL have been copied to the initial guess vector.

Template Parameters

It	Type of the iterators over the range

Parameters

begin	The begin iterator of the range
end	The first-past-the-end iterator of the range

◆ FillInitialGuess() [2/2]

template<typename T >

void ptems::GMRESSolver< T >::FillInitialGuess ( T value )

inline

Fills the initial guess vector with a constant.

Parameters

value Value to fill initial guess vector with

◆ InitialGuess() [1/2]

template<typename T >

T& ptems::GMRESSolver< T >::InitialGuess ( std::size_t i )

inline

Returns a mutable reference to the specified entry of the initial guess.

Can be used to populate the initial guess

Exceptions

std::out_of_range If i is not in the range [0, size())

Parameters

i	Index of entry in initial guess

Returns: Mutable reference to entry in initial guess

◆ InitialGuess() [2/2]

template<typename T >

const T& ptems::GMRESSolver< T >::InitialGuess ( std::size_t i ) const

inline

Returns a const reference to the specified entry of the initial guess.

Can be used to populate the initial guess

Exceptions

std::out_of_range If i is not in the range [0, size())

Parameters

i	Index of entry in initial guess

Returns: Const reference to entry in initial guess

◆ operator()() [1/3]

template<typename T , typename Ref = T&, typename ConstRef = const T&>

virtual std::vector<T> ptems::LinearSolver< T, Ref, ConstRef >::operator()	(	const std::vector< T > &	rhs,
		std::size_t	offsetRHS = `0`,
		std::size_t	lenRHS = `-1`
	)

inlinevirtualinherited

Solves the linear system with the specified right-hand side.

Parameters

rhs	The right hand side vector
offsetRHS	If using distributed matrix/rhs construction specifies the offset to the start of the right hand side vector populated by this process
lenRHS	If using distributed matrix/rhs construction specifies the length of the right hand side vector populated by this process (or greater than size() for all)

Returns: std::vector<T>

◆ operator()() [2/3]

template<typename T , typename Ref = T&, typename ConstRef = const T&>

virtual reference ptems::LinearSolver< T, Ref, ConstRef >::operator()	(	std::size_t	i,
		std::size_t	j
	)

inlinevirtualinherited

Gets a reference to the specified matrix entry.

Exceptions

std::out_of_range	If the row or column index are not less than the linear system size
std::invalid_argument	If the entry is not a non-zero entry of the sparse matrix

Parameters

i	The row index
j	The column index

Returns: A reference to the element if its a non-zero entry

◆ operator()() [3/3]

template<typename T , typename Ref = T&, typename ConstRef = const T&>

virtual const_reference ptems::LinearSolver< T, Ref, ConstRef >::operator()	(	std::size_t	i,
		std::size_t	j
	)		const

inlinevirtualinherited

Gets a const reference to the specified matrix entry.

Exceptions

std::out_of_range	If the row or column index are not less than the linear system size
std::invalid_argument	If the entry is not a non-zero entry of the sparse matrix

Parameters

i	The row index
j	The column index

Returns: A const reference to the element if its a non-zero entry

◆ size()

template<typename T >

std::size_t ptems::GMRESSolver< T >::size ( ) const

inlineoverridevirtual

Gets the size of the linear system.

Returns: The number of rows and columns in the sparse matrix

Implements ptems::LinearSolver< T, Ref, ConstRef >.

◆ Solve()

template<typename T >

virtual std::vector<T> ptems::GMRESSolver< T >::Solve	(	const std::vector< T > &	rhs,
		std::size_t	offsetRHS = `0`,
		std::size_t	lenRHS = `-1`
	)

inlineoverridevirtual

Solves the linear system with the specified right-hand side.

Parameters

rhs	The right hand side vector
offsetRHS	If using distributed matrix/rhs construction specifies the offset to the start of the right hand side vector populated by this process
lenRHS	If using distributed matrix/rhs construction specifies the length of the right hand side vector populated by this process (or greater than size() for all)

Returns: std::vector<T>

Implements ptems::LinearSolver< T, Ref, ConstRef >.

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

ptems/solvers/gmres.hpp

Public Types

Public Member Functions

Detailed Description

template<typename T> class ptems::GMRESSolver< T >

Member Typedef Documentation

◆ const_reference

◆ optional_const_reference

◆ optional_reference

◆ real_type

◆ reference

◆ value_type

Constructor & Destructor Documentation

◆ GMRESSolver() [1/2]

◆ GMRESSolver() [2/2]

Member Function Documentation

◆ Clear()

◆ DistributedConstruction()

◆ Entry() [1/2]

◆ Entry() [2/2]

◆ FillInitialGuess() [1/2]

◆ FillInitialGuess() [2/2]

◆ InitialGuess() [1/2]

◆ InitialGuess() [2/2]

◆ operator()() [1/3]

◆ operator()() [2/3]

◆ operator()() [3/3]

◆ size()

◆ Solve()

template<typename T>
class ptems::GMRESSolver< T >