#include <deal.II/multigrid/mg_transfer_matrix_free.h>

Inheritance diagram for MGTransferMatrixFree< dim, Number >:

Public Member Functions
	MGTransferMatrixFree ()

	MGTransferMatrixFree (const MGConstrainedDoFs &mg_constrained_dofs)

virtual	~MGTransferMatrixFree ()

void	initialize_constraints (const MGConstrainedDoFs &mg_constrained_dofs)

void	clear ()

void	build (const DoFHandler< dim, dim > &mg_dof)

virtual void	prolongate (const unsigned int to_level, LinearAlgebra::distributed::Vector< Number > &dst, const LinearAlgebra::distributed::Vector< Number > &src) const

virtual void	restrict_and_add (const unsigned int from_level, LinearAlgebra::distributed::Vector< Number > &dst, const LinearAlgebra::distributed::Vector< Number > &src) const

std::size_t	memory_consumption () const

Public Member Functions inherited from MGLevelGlobalTransfer< LinearAlgebra::distributed::Vector< Number > >
void	clear ()

template<int dim, typename Number2 , int spacedim>
void	copy_to_mg (const DoFHandler< dim, spacedim > &mg_dof, MGLevelObject< LinearAlgebra::distributed::Vector< Number > > &dst, const LinearAlgebra::distributed::Vector< Number2 > &src) const

template<int dim, typename Number2 , int spacedim>
void	copy_from_mg (const DoFHandler< dim, spacedim > &mg_dof, LinearAlgebra::distributed::Vector< Number2 > &dst, const MGLevelObject< LinearAlgebra::distributed::Vector< Number > > &src) const

template<int dim, typename Number2 , int spacedim>
void	copy_from_mg_add (const DoFHandler< dim, spacedim > &mg_dof, LinearAlgebra::distributed::Vector< Number2 > &dst, const MGLevelObject< LinearAlgebra::distributed::Vector< Number > > &src) const

void	set_component_to_block_map (const std::vector< unsigned int > &map)

std::size_t	memory_consumption () const

void	print_indices (std::ostream &os) const

Public Member Functions inherited from MGTransferBase< LinearAlgebra::distributed::Vector< Number > >
virtual	~MGTransferBase ()

Public Member Functions inherited from Subscriptor
	Subscriptor ()

	Subscriptor (const Subscriptor &)

	Subscriptor (Subscriptor &&)

virtual	~Subscriptor ()

Subscriptor &	operator= (const Subscriptor &)

Subscriptor &	operator= (Subscriptor &&)

void	subscribe (const char *identifier=0) const

void	unsubscribe (const char *identifier=0) const

unsigned int	n_subscriptions () const

void	list_subscribers () const

template<class Archive >
void	serialize (Archive &ar, const unsigned int version)

Static Public Member Functions
static ::ExceptionBase &	ExcNoProlongation ()

Static Public Member Functions inherited from Subscriptor
static ::ExceptionBase &	ExcInUse (int arg1, char *arg2, std::string &arg3)

static ::ExceptionBase &	ExcNoSubscriber (char arg1, char arg2)

Private Member Functions
template<int degree>
void	do_prolongate_add (const unsigned int to_level, LinearAlgebra::distributed::Vector< Number > &dst, const LinearAlgebra::distributed::Vector< Number > &src) const

template<int degree>
void	do_restrict_add (const unsigned int from_level, LinearAlgebra::distributed::Vector< Number > &dst, const LinearAlgebra::distributed::Vector< Number > &src) const

Private Attributes
unsigned int	fe_degree

bool	element_is_continuous

unsigned int	n_components

unsigned int	n_child_cell_dofs

std::vector< std::vector< unsigned int > >	level_dof_indices

std::vector< std::vector< std::pair< unsigned int, unsigned int > > >	parent_child_connect

std::vector< unsigned int >	n_owned_level_cells

AlignedVector< VectorizedArray< Number > >	prolongation_matrix_1d

AlignedVector< VectorizedArray< Number > >	evaluation_data

std::vector< AlignedVector< VectorizedArray< Number > > >	weights_on_refined

std::vector< std::vector< std::vector< unsigned short > > >	dirichlet_indices

Additional Inherited Members
Protected Member Functions inherited from MGLevelGlobalTransfer< LinearAlgebra::distributed::Vector< Number > >
template<int dim, int spacedim>
void	fill_and_communicate_copy_indices (const DoFHandler< dim, spacedim > &mg_dof)

Protected Attributes inherited from MGLevelGlobalTransfer< LinearAlgebra::distributed::Vector< Number > >
std::vector< types::global_dof_index >	sizes

std::vector< std::vector< std::pair< unsigned int, unsigned int > > >	copy_indices

std::vector< std::vector< std::pair< unsigned int, unsigned int > > >	copy_indices_global_mine

std::vector< std::vector< std::pair< unsigned int, unsigned int > > >	copy_indices_level_mine

bool	perform_plain_copy

std::vector< unsigned int >	component_to_block_map

SmartPointer< const MGConstrainedDoFs, MGLevelGlobalTransfer< LinearAlgebra::distributed::Vector< Number > > >	mg_constrained_dofs

LinearAlgebra::distributed::Vector< Number >	ghosted_global_vector

MGLevelObject< LinearAlgebra::distributed::Vector< Number > >	ghosted_level_vector

Detailed Description

template<int dim, typename Number>
class MGTransferMatrixFree< dim, Number >

Implementation of the MGTransferBase interface for which the transfer operations is implemented in a matrix-free way based on the interpolation matrices of the underlying finite element. This requires considerably less memory than MGTransferPrebuilt and can also be considerably faster than that variant.

This class currently only works for tensor-product finite elements based on FE_Q and FE_DGQ elements, including systems involving multiple components of one of these elements. Systems with different elements or other elements are currently not implemented.

Author: Martin Kronbichler

Date: 2016

Definition at line 52 of file mg_transfer_matrix_free.h.

Constructor & Destructor Documentation

◆ MGTransferMatrixFree() [1/2]

template<int dim, typename Number >

MGTransferMatrixFree< dim, Number >::MGTransferMatrixFree ( )

Constructor without constraint matrices. Use this constructor only with discontinuous finite elements or with no local refinement.

Definition at line 38 of file mg_transfer_matrix_free.cc.

◆ MGTransferMatrixFree() [2/2]

template<int dim, typename Number >

MGTransferMatrixFree< dim, Number >::MGTransferMatrixFree ( const MGConstrainedDoFs & mg_constrained_dofs )

Constructor with constraints. Equivalent to the default constructor followed by initialize_constraints().

Definition at line 49 of file mg_transfer_matrix_free.cc.

◆ ~MGTransferMatrixFree()

template<int dim, typename Number >

MGTransferMatrixFree< dim, Number >::~MGTransferMatrixFree ( )

virtual

Destructor.

Definition at line 62 of file mg_transfer_matrix_free.cc.

Member Function Documentation

◆ initialize_constraints()

template<int dim, typename Number >

void MGTransferMatrixFree< dim, Number >::initialize_constraints ( const MGConstrainedDoFs & mg_constrained_dofs )

Initialize the constraints to be used in build().

Definition at line 69 of file mg_transfer_matrix_free.cc.

◆ clear()

template<int dim, typename Number >

void MGTransferMatrixFree< dim, Number >::clear ( )

Reset the object to the state it had right after the default constructor.

Definition at line 77 of file mg_transfer_matrix_free.cc.

◆ build()

template<int dim, typename Number >

void MGTransferMatrixFree< dim, Number >::build ( const DoFHandler< dim, dim > & mg_dof )

Actually build the information for the prolongation for each level.

Definition at line 96 of file mg_transfer_matrix_free.cc.

◆ prolongate()

template<int dim, typename Number >

void MGTransferMatrixFree< dim, Number >::prolongate	(	const unsigned int	to_level,
		LinearAlgebra::distributed::Vector< Number > &	dst,
		const LinearAlgebra::distributed::Vector< Number > &	src
	)		const

virtual

Prolongate a vector from level to_level-1 to level to_level using the embedding matrices of the underlying finite element. The previous content of dst is overwritten.

Parameters

to_level	The index of the level to prolongate to, which is the level of `dst`.
src	is a vector with as many elements as there are degrees of freedom on the coarser level involved.
dst	has as many elements as there are degrees of freedom on the finer level.

Implements MGTransferBase< LinearAlgebra::distributed::Vector< Number > >.

Definition at line 154 of file mg_transfer_matrix_free.cc.

◆ restrict_and_add()

template<int dim, typename Number >

void MGTransferMatrixFree< dim, Number >::restrict_and_add	(	const unsigned int	from_level,
		LinearAlgebra::distributed::Vector< Number > &	dst,
		const LinearAlgebra::distributed::Vector< Number > &	src
	)		const

virtual

Restrict a vector from level from_level to level from_level-1 using the transpose operation of the prolongate() method. If the region covered by cells on level from_level is smaller than that of level from_level-1 (local refinement), then some degrees of freedom in dst are active and will not be altered. For the other degrees of freedom, the result of the restriction is added.

Parameters

from_level	The index of the level to restrict from, which is the level of `src`.
src	is a vector with as many elements as there are degrees of freedom on the finer level involved.
dst	has as many elements as there are degrees of freedom on the coarser level.

Implements MGTransferBase< LinearAlgebra::distributed::Vector< Number > >.

Definition at line 218 of file mg_transfer_matrix_free.cc.

◆ memory_consumption()

template<int dim, typename Number >

std::size_t MGTransferMatrixFree< dim, Number >::memory_consumption ( ) const

Memory used by this object.

Definition at line 542 of file mg_transfer_matrix_free.cc.

◆ do_prolongate_add()

template<int dim, typename Number >

template<int degree>

void MGTransferMatrixFree< dim, Number >::do_prolongate_add	(	const unsigned int	to_level,
		LinearAlgebra::distributed::Vector< Number > &	dst,
		const LinearAlgebra::distributed::Vector< Number > &	src
	)		const

private

Performs templated prolongation operation

Definition at line 360 of file mg_transfer_matrix_free.cc.

◆ do_restrict_add()

template<int dim, typename Number >

template<int degree>

void MGTransferMatrixFree< dim, Number >::do_restrict_add	(	const unsigned int	from_level,
		LinearAlgebra::distributed::Vector< Number > &	dst,
		const LinearAlgebra::distributed::Vector< Number > &	src
	)		const

private

Performs templated restriction operation

Definition at line 449 of file mg_transfer_matrix_free.cc.

Member Data Documentation

◆ fe_degree

template<int dim, typename Number>

unsigned int MGTransferMatrixFree< dim, Number >::fe_degree

private

Stores the degree of the finite element contained in the DoFHandler passed to build(). The selection of the computational kernel is based on this number.

Definition at line 144 of file mg_transfer_matrix_free.h.

◆ element_is_continuous

template<int dim, typename Number>

bool MGTransferMatrixFree< dim, Number >::element_is_continuous

private

Stores whether the element is continuous and there is a joint degree of freedom in the center of the 1D line.

Definition at line 150 of file mg_transfer_matrix_free.h.

◆ n_components

template<int dim, typename Number>

unsigned int MGTransferMatrixFree< dim, Number >::n_components

private

Stores the number of components in the finite element contained in the DoFHandler passed to build().

Definition at line 156 of file mg_transfer_matrix_free.h.

◆ n_child_cell_dofs

template<int dim, typename Number>

unsigned int MGTransferMatrixFree< dim, Number >::n_child_cell_dofs

private

Stores the number of degrees of freedom on all child cells. It is 2^dim*fe.dofs_per_cell for DG elements and somewhat less for continuous elements.

Definition at line 163 of file mg_transfer_matrix_free.h.

◆ level_dof_indices

template<int dim, typename Number>

std::vector<std::vector<unsigned int> > MGTransferMatrixFree< dim, Number >::level_dof_indices

private

Holds the indices for cells on a given level, extracted from DoFHandler for fast access. All DoF indices on a given level are stored as a plain array (since this class assumes constant DoFs per cell). To index into this array, use the cell number times dofs_per_cell.

This array first is arranged such that all locally owned level cells come first (found in the variable n_owned_level_cells) and then other cells necessary for the transfer to the next level.

Definition at line 175 of file mg_transfer_matrix_free.h.

◆ parent_child_connect

template<int dim, typename Number>

std::vector<std::vector<std::pair<unsigned int,unsigned int> > > MGTransferMatrixFree< dim, Number >::parent_child_connect

private

Stores the connectivity from parent to child cell numbers for each level.

Definition at line 180 of file mg_transfer_matrix_free.h.

◆ n_owned_level_cells

template<int dim, typename Number>

std::vector<unsigned int> MGTransferMatrixFree< dim, Number >::n_owned_level_cells

private

Stores the number of cells owned on a given process (sets the bounds for the worker loops) for each level.

Definition at line 186 of file mg_transfer_matrix_free.h.

◆ prolongation_matrix_1d

template<int dim, typename Number>

AlignedVector<VectorizedArray<Number> > MGTransferMatrixFree< dim, Number >::prolongation_matrix_1d

private

Holds the one-dimensional embedding (prolongation) matrix from mother element to all the children.

Definition at line 192 of file mg_transfer_matrix_free.h.

◆ evaluation_data

template<int dim, typename Number>

AlignedVector<VectorizedArray<Number> > MGTransferMatrixFree< dim, Number >::evaluation_data

mutableprivate

Holds the temporary values for the tensor evaluation

Definition at line 197 of file mg_transfer_matrix_free.h.

◆ weights_on_refined

template<int dim, typename Number>

std::vector<AlignedVector<VectorizedArray<Number> > > MGTransferMatrixFree< dim, Number >::weights_on_refined

private

For continuous elements, restriction is not additive and we need to weight the result at the end of prolongation (and at the start of restriction) by the valence of the degrees of freedom, i.e., on how many elements they appear. We store the data in vectorized form to allow for cheap access. Moreover, we utilize the fact that we only need to store 3^dim indices.

Data is organized in terms of each level (outer vector) and the cells on each level (inner vector).

Definition at line 210 of file mg_transfer_matrix_free.h.

◆ dirichlet_indices

template<int dim, typename Number>

std::vector<std::vector<std::vector<unsigned short> > > MGTransferMatrixFree< dim, Number >::dirichlet_indices

private

Stores the local indices of Dirichlet boundary conditions on cells for all levels (outer index), the cells within the levels (second index), and the indices on the cell (inner index).

Definition at line 217 of file mg_transfer_matrix_free.h.

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

deal.II/multigrid/mg_transfer_matrix_free.h
source/multigrid/mg_transfer_matrix_free.cc

Public Member Functions

Static Public Member Functions

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

template<int dim, typename Number> class MGTransferMatrixFree< dim, Number >

Constructor & Destructor Documentation

◆ MGTransferMatrixFree() [1/2]

◆ MGTransferMatrixFree() [2/2]

◆ ~MGTransferMatrixFree()

Member Function Documentation

◆ initialize_constraints()

◆ clear()

◆ build()

◆ prolongate()

◆ restrict_and_add()

◆ memory_consumption()

◆ do_prolongate_add()

◆ do_restrict_add()

Member Data Documentation

◆ fe_degree

◆ element_is_continuous

◆ n_components

◆ n_child_cell_dofs

◆ level_dof_indices

◆ parent_child_connect

◆ n_owned_level_cells

◆ prolongation_matrix_1d

◆ evaluation_data

◆ weights_on_refined

◆ dirichlet_indices

template<int dim, typename Number>
class MGTransferMatrixFree< dim, Number >