This class represents the distribution index arrays across processes. An index array is a contiguous collection of N+1 block indices [0, 1, . . ., N] that are distributed across processes M processes. On a given process, the IndexMap stores a portion of the index set using local indices [0, 1, . . . , n], and a map from the local block indices to a unique global block index. More...

#include <IndexMap.h>

Public Types
enum	Mode { insert, add }
	Mode for reverse scatter operation.

enum	Direction { reverse, forward, symmetric }
	Edge directions of neighborhood communicator.

Public Member Functions
	IndexMap (MPI_Comm comm, std::int32_t local_size, int block_size)
	Create an non-overlapping index map with local_size owned blocks on this process. More...

	IndexMap (MPI_Comm mpi_comm, std::int32_t local_size, const std::vector< int > &dest_ranks, const std::vector< std::int64_t > &ghosts, const std::vector< int > &src_ranks, int block_size)
	Create an index map with local_size owned blocks on this process, and blocks have size block_size. More...

	IndexMap (MPI_Comm mpi_comm, std::int32_t local_size, const std::vector< int > &dest_ranks, const Eigen::Ref< const Eigen::Array< std::int64_t, Eigen::Dynamic, 1 >> &ghosts, const std::vector< int > &src_ranks, int block_size)
	Create an index map. More...

	IndexMap (const IndexMap &map)=delete
	Copy constructor.

	IndexMap (IndexMap &&map)=default
	Move constructor.

	~IndexMap ()=default
	Destructor.

std::array< std::int64_t, 2 >	local_range () const noexcept
	Range of indices (global) owned by this process.

int	block_size () const noexcept
	Block size.

std::int32_t	num_ghosts () const
	Number of ghost indices on this process.

std::int32_t	size_local () const
	Number of indices owned by on this process.

std::int64_t	size_global () const
	Number indices across communicator.

const Eigen::Array< std::int64_t, Eigen::Dynamic, 1 > &	ghosts () const
	Local-to-global map for ghosts (local indexing beyond end of local range)

MPI_Comm	comm (Direction dir=Direction::symmetric) const
	Return a MPI communicator with attached distributed graph topology information. More...

Eigen::Array< std::int64_t, Eigen::Dynamic, 1 >	local_to_global (const Eigen::Ref< const Eigen::Array< std::int32_t, Eigen::Dynamic, 1 >> &indices, bool blocked=true) const
	Compute global indices for array of local indices. More...

std::vector< std::int64_t >	local_to_global (const std::vector< std::int32_t > &indices, bool blocked=true) const

std::vector< std::int32_t >	global_to_local (const std::vector< std::int64_t > &indices, bool blocked=true) const
	Compute local indices for array of global indices. More...

std::vector< std::int32_t >	global_to_local (const Eigen::Ref< const Eigen::Array< std::int64_t, Eigen::Dynamic, 1 >> &indices, bool blocked=true) const
	Compute local indices for array of global indices. More...

std::vector< std::int64_t >	global_indices (bool blocked=true) const
	Global indices. More...

const std::vector< std::int32_t > &	shared_indices () const

Eigen::Array< int, Eigen::Dynamic, 1 >	ghost_owner_rank () const
	Owner rank (on global communicator) of each ghost entry.

Eigen::Array< std::int64_t, Eigen::Dynamic, 1 >	indices (bool unroll_block) const
	Return array of global indices for all indices on this process, including ghosts.

std::map< std::int32_t, std::set< int > >	compute_shared_indices () const

void	scatter_fwd (const std::vector< std::int64_t > &local_data, std::vector< std::int64_t > &remote_data, int n) const
	Send n values for each index that is owned to processes that have the index as a ghost. The size of the input array local_data must be the same as n * size_local(). More...

void	scatter_fwd (const std::vector< std::int32_t > &local_data, std::vector< std::int32_t > &remote_data, int n) const
	Send n values for each index that is owned to processes that have the index as a ghost. The size of the input array local_data must be the same as n * size_local(). More...

std::vector< std::int64_t >	scatter_fwd (const std::vector< std::int64_t > &local_data, int n) const
	Send n values for each index that is owned to processes that have the index as a ghost. The size of the input array local_data must be the same as n * size_local(). More...

std::vector< std::int32_t >	scatter_fwd (const std::vector< std::int32_t > &local_data, int n) const
	Send n values for each index that is owned to processes that have the index as a ghost. More...

void	scatter_rev (std::vector< std::int64_t > &local_data, const std::vector< std::int64_t > &remote_data, int n, IndexMap::Mode op) const
	Send n values for each ghost index to owning to the process. More...

void	scatter_rev (std::vector< std::int32_t > &local_data, const std::vector< std::int32_t > &remote_data, int n, IndexMap::Mode op) const
	Send n values for each ghost index to owning to the process. More...

Detailed Description

This class represents the distribution index arrays across processes. An index array is a contiguous collection of N+1 block indices [0, 1, . . ., N] that are distributed across processes M processes. On a given process, the IndexMap stores a portion of the index set using local indices [0, 1, . . . , n], and a map from the local block indices to a unique global block index.

Constructor & Destructor Documentation

◆ IndexMap() [1/3]

IndexMap::IndexMap	(	MPI_Comm	comm,
		std::int32_t	local_size,
		int	block_size
	)

Create an non-overlapping index map with local_size owned blocks on this process.

Note: Collective

Parameters

[in]	comm	The MPI communicator
[in]	local_size	Local size of the IndexMap, i.e. the number of owned entries
[in]	block_size	The block size of the IndexMap

◆ IndexMap() [2/3]

IndexMap::IndexMap	(	MPI_Comm	mpi_comm,
		std::int32_t	local_size,
		const std::vector< int > &	dest_ranks,
		const std::vector< std::int64_t > &	ghosts,
		const std::vector< int > &	src_ranks,
		int	block_size
	)

Create an index map with local_size owned blocks on this process, and blocks have size block_size.

Note: Collective

Parameters

[in]	mpi_comm	The MPI communicator
[in]	local_size	Local size of the IndexMap, i.e. the number of owned entries
[in]	dest_ranks	Ranks that 'ghost' indices that are owned by the calling rank. I.e., ranks that the caller will send data to when updating ghost values.
[in]	ghosts	The global indices of ghost entries
[in]	src_ranks	Owner rank (on global communicator) of each entry in `ghosts`
[in]	block_size	The block size of the IndexMap

◆ IndexMap() [3/3]

IndexMap::IndexMap	(	MPI_Comm	mpi_comm,
		std::int32_t	local_size,
		const std::vector< int > &	dest_ranks,
		const Eigen::Ref< const Eigen::Array< std::int64_t, Eigen::Dynamic, 1 >> &	ghosts,
		const std::vector< int > &	src_ranks,
		int	block_size
	)

Create an index map.

Note: Collective

Parameters

[in]	mpi_comm	The MPI communicator
[in]	local_size	Local size of the IndexMap, i.e. the number of owned entries
[in]	dest_ranks	Ranks that ghost indices owned by the calling rank
[in]	ghosts	The global indices of ghost entries
[in]	src_ranks	Owner rank (on global communicator) of each ghost entry
[in]	block_size	The block size of the IndexMap

Member Function Documentation

◆ comm()

MPI_Comm IndexMap::comm ( Direction dir = Direction::symmetric ) const

Return a MPI communicator with attached distributed graph topology information.

Parameters

[in] dir Edge direction of communicator (forward, reverse, symmetric)

Returns: A neighborhood communicator for the specified edge direction

◆ compute_shared_indices()

std::map< std::int32_t, std::set< int > > IndexMap::compute_shared_indices ( ) const

Todo:: Aim to remove this function? If it's kept, should it work with neighborhood ranks?

Compute map from each local (owned) index to the set of ranks that have the index as a ghost

Returns: shared indices

◆ global_indices()

std::vector< std::int64_t > IndexMap::global_indices ( bool blocked = true ) const

Global indices.

Returns: The global index for all local indices (0, 1, 2, ...) on this process, including ghosts

◆ global_to_local() [1/2]

std::vector< std::int32_t > IndexMap::global_to_local	(	const Eigen::Ref< const Eigen::Array< std::int64_t, Eigen::Dynamic, 1 >> &	indices,
		bool	blocked = `true`
	)		const

Compute local indices for array of global indices.

Parameters

[in]	indices	Global indices
[in]	blocked	If true work with blocked indices. If false the input indices are not block-wise.

Returns: The local of the corresponding global index in indices. Return -1 if the local index does not exist on this process.

◆ global_to_local() [2/2]

std::vector< std::int32_t > IndexMap::global_to_local	(	const std::vector< std::int64_t > &	indices,
		bool	blocked = `true`
	)		const

Compute local indices for array of global indices.

Parameters

[in]	indices	Global indices
[in]	blocked	If true work with blocked indices. If false the input indices are not block-wise.

Returns: The local of the corresponding global index in indices. Returns -1 if the local index does not exist on this process.

◆ local_to_global() [1/2]

Eigen::Array< std::int64_t, Eigen::Dynamic, 1 > IndexMap::local_to_global	(	const Eigen::Ref< const Eigen::Array< std::int32_t, Eigen::Dynamic, 1 >> &	indices,
		bool	blocked = `true`
	)		const

Compute global indices for array of local indices.

Parameters

[in]	indices	Local indices
[in]	blocked	If true work with blocked indices. If false the input indices are not block-wise.

Returns: The global index of the corresponding local index in indices.

◆ local_to_global() [2/2]

std::vector< std::int64_t > IndexMap::local_to_global	(	const std::vector< std::int32_t > &	indices,
		bool	blocked = `true`
	)		const

Todo:: Consider removing this function in favour of the version that accepts an Eigen array.

Compute global indices for array of local indices

Parameters

[in]	indices	Local indices
[in]	blocked	If true work with blocked indices. If false the input indices are not block-wise.

Returns: The global index of the corresponding local index in indices.

◆ scatter_fwd() [1/4]

std::vector< std::int32_t > IndexMap::scatter_fwd	(	const std::vector< std::int32_t > &	local_data,
		int	n
	)		const

Send n values for each index that is owned to processes that have the index as a ghost.

Parameters

[in]	local_data	Local data associated with each owned local index to be sent to process where the data is ghosted. Size must be n * size_local().
[in]	n	Number of data items per index

Returns: Ghost data on this process received from the owning process. Size will be n * num_ghosts().

◆ scatter_fwd() [2/4]

void IndexMap::scatter_fwd	(	const std::vector< std::int32_t > &	local_data,
		std::vector< std::int32_t > &	remote_data,
		int	n
	)		const

Send n values for each index that is owned to processes that have the index as a ghost. The size of the input array local_data must be the same as n * size_local().

Parameters

[in]	local_data	Local data associated with each owned local index to be sent to process where the data is ghosted. Size must be n * size_local().
[in,out]	remote_data	Ghost data on this process received from the owning process. Size will be n * num_ghosts().
[in]	n	Number of data items per index

◆ scatter_fwd() [3/4]

std::vector< std::int64_t > IndexMap::scatter_fwd	(	const std::vector< std::int64_t > &	local_data,
		int	n
	)		const

Send n values for each index that is owned to processes that have the index as a ghost. The size of the input array local_data must be the same as n * size_local().

Parameters

[in]	local_data	Local data associated with each owned local index to be sent to process where the data is ghosted. Size must be n * size_local().
[in]	n	Number of data items per index

Returns: Ghost data on this process received from the owning process. Size will be n * num_ghosts().

◆ scatter_fwd() [4/4]

void IndexMap::scatter_fwd	(	const std::vector< std::int64_t > &	local_data,
		std::vector< std::int64_t > &	remote_data,
		int	n
	)		const

Send n values for each index that is owned to processes that have the index as a ghost. The size of the input array local_data must be the same as n * size_local().

Parameters

[in]	local_data	Local data associated with each owned local index to be sent to process where the data is ghosted. Size must be n * size_local().
[in,out]	remote_data	Ghost data on this process received from the owning process. Size will be n * num_ghosts().
[in]	n	Number of data items per index

◆ scatter_rev() [1/2]

void IndexMap::scatter_rev	(	std::vector< std::int32_t > &	local_data,
		const std::vector< std::int32_t > &	remote_data,
		int	n,
		IndexMap::Mode	op
	)		const

Send n values for each ghost index to owning to the process.

Parameters

[in,out]	local_data	Local data associated with each owned local index to be sent to process where the data is ghosted. Size must be n * size_local().
[in]	remote_data	Ghost data on this process received from the owning process. Size will be n * num_ghosts().
[in]	n	Number of data items per index
[in]	op	Sum or set received values in local_data

◆ scatter_rev() [2/2]

void IndexMap::scatter_rev	(	std::vector< std::int64_t > &	local_data,
		const std::vector< std::int64_t > &	remote_data,
		int	n,
		IndexMap::Mode	op
	)		const

Send n values for each ghost index to owning to the process.

Parameters

[in,out]	local_data	Local data associated with each owned local index to be sent to process where the data is ghosted. Size must be n * size_local().
[in]	remote_data	Ghost data on this process received from the owning process. Size will be n * num_ghosts().
[in]	n	Number of data items per index
[in]	op	Sum or set received values in local_data

◆ shared_indices()

const std::vector< std::int32_t > & IndexMap::shared_indices ( ) const

Todo:: Reconsider name Local (owned) indices shared with neighbor processes, i.e. are ghosts on other processes

Returns: List of indices that are ghosted on other processes

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

/build/dolfinx-EGDDvI/dolfinx-2019.2.0~git20200723.696fbc0/cpp/dolfinx/common/IndexMap.h
/build/dolfinx-EGDDvI/dolfinx-2019.2.0~git20200723.696fbc0/cpp/dolfinx/common/IndexMap.cpp

Public Types

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ IndexMap() [1/3]

◆ IndexMap() [2/3]

◆ IndexMap() [3/3]

Member Function Documentation

◆ comm()

◆ compute_shared_indices()

◆ global_indices()

◆ global_to_local() [1/2]

◆ global_to_local() [2/2]

◆ local_to_global() [1/2]

◆ local_to_global() [2/2]

◆ scatter_fwd() [1/4]

◆ scatter_fwd() [2/4]

◆ scatter_fwd() [3/4]

◆ scatter_fwd() [4/4]

◆ scatter_rev() [1/2]

◆ scatter_rev() [2/2]

◆ shared_indices()