gko::batch::preconditioner::Jacobi< ValueType, IndexType > Class Template Reference

A block-Jacobi preconditioner is a block-diagonal linear operator, obtained by inverting the diagonal blocks (stored in a dense row major fashion) of the source operator. More...

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

Inheritance diagram for gko::batch::preconditioner::Jacobi< ValueType, IndexType >:

Collaboration diagram for gko::batch::preconditioner::Jacobi< ValueType, IndexType >:

Classes
class	Factory
struct	parameters_type

Public Types
using	value_type = ValueType
using	index_type = IndexType
using	matrix_type = batch::matrix::Csr< ValueType, IndexType >
Public Types inherited from gko::EnablePolymorphicAssignment< Jacobi< ValueType, IndexType > >
using	result_type = Jacobi< ValueType, IndexType >
Public Types inherited from gko::ConvertibleTo< Jacobi< ValueType, IndexType > >
using	result_type = Jacobi< ValueType, IndexType >

Public Member Functions
const index_type *	get_const_block_pointers () const noexcept
	Returns the block pointers. More...
const index_type *	get_const_map_block_to_row () const noexcept
	Returns the mapping between the blocks and the row id. More...
const index_type *	get_const_blocks_cumulative_offsets () const noexcept
	Returns the cumulative blocks storage array. More...
uint32	get_max_block_size () const noexcept
	Returns the max block size. More...
size_type	get_num_blocks () const noexcept
	Returns the number of blocks in an individual batch entry. More...
const value_type *	get_const_blocks () const noexcept
	Returns the pointer to the memory used for storing the block data. More...
size_type	get_num_stored_elements () const noexcept
	Returns the number of elements explicitly stored in the dense blocks. More...
const parameters_type &	get_parameters () const
Public Member Functions inherited from gko::EnableAbstractPolymorphicObject< Jacobi< ValueType, IndexType >, BatchLinOp >
std::unique_ptr< Jacobi< ValueType, IndexType > >	create_default (std::shared_ptr< const Executor > exec) const
std::unique_ptr< Jacobi< ValueType, IndexType > >	create_default () const
std::unique_ptr< Jacobi< ValueType, IndexType > >	clone (std::shared_ptr< const Executor > exec) const
std::unique_ptr< Jacobi< ValueType, IndexType > >	clone () const
Jacobi< ValueType, IndexType > *	copy_from (const PolymorphicObject *other)
std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, Jacobi< ValueType, IndexType > > *	copy_from (std::unique_ptr< Derived > &&other)
std::enable_if_t< std::is_base_of< PolymorphicObject, std::decay_t< Derived > >::value, Jacobi< ValueType, IndexType > > *	copy_from (const std::unique_ptr< Derived > &other)
Jacobi< ValueType, IndexType > *	copy_from (const std::shared_ptr< const PolymorphicObject > &other)
Jacobi< ValueType, IndexType > *	move_from (ptr_param< PolymorphicObject > other)
Jacobi< ValueType, IndexType > *	clear ()
Public Member Functions inherited from gko::EnablePolymorphicAssignment< Jacobi< ValueType, 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< Jacobi< ValueType, 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())

Friends
class	EnableBatchLinOp< Jacobi >
class	EnablePolymorphicObject< Jacobi, BatchLinOp >

Detailed Description

template<typename ValueType = default_precision, typename IndexType = int32>
class gko::batch::preconditioner::Jacobi< ValueType, IndexType >

A block-Jacobi preconditioner is a block-diagonal linear operator, obtained by inverting the diagonal blocks (stored in a dense row major fashion) of the source operator.

With the batched preconditioners, it is required that all items in the batch have the same sparsity pattern. The detection of the blocks and the block pointers require that the sparsity pattern of all the items be the same. Other cases is undefined behaviour. The input batch matrix must be in batch::Csr matrix format or must be convertible to batch::Csr matrix format. The block detection algorithm and the conversion to dense blocks kernels require this assumption.

Note

In a fashion similar to the non-batched Jacobi preconditioner, the maximum possible size of the diagonal blocks is equal to the maximum warp size on the device (32 for NVIDIA GPUs, 64 for AMD GPUs).

Template Parameters

ValueType	value precision of matrix elements
IndexType	index precision of matrix elements

Member Function Documentation

get_const_block_pointers()

template<typename ValueType = default_precision, typename IndexType = int32>

const index_type* gko::batch::preconditioner::Jacobi< ValueType, IndexType >::get_const_block_pointers ( ) const

inlinenoexcept

Returns the block pointers.

Note

Returns nullptr in case of a scalar jacobi preconditioner (max_block_size = 1).

Returns

the block pointers

References gko::array< ValueType >::get_const_data().

get_const_blocks()

template<typename ValueType = default_precision, typename IndexType = int32>

const value_type* gko::batch::preconditioner::Jacobi< ValueType, IndexType >::get_const_blocks ( ) const

inlinenoexcept

Returns the pointer to the memory used for storing the block data.

Element (i, j) of the block, which belongs to the batch entry with index = "batch_id" and has local id = "block_id" within its batch entry is stored at the address = get_const_blocks() + detail::get_global_block_offset(batch_id, num_blocks, block_id, cumulative_blocks_storage) + i * detail::get_stride(block_id, block_pointers) + j

Note

Returns nullptr in case of a scalar jacobi preconditioner (max_block_size = 1). The blocks array is empty in case of scalar jacobi preconditioner as the preconditioner is generated inside the batched solver kernel.

Returns

the pointer to the memory used for storing the block data

References gko::array< ValueType >::get_const_data().

get_const_blocks_cumulative_offsets()

template<typename ValueType = default_precision, typename IndexType = int32>

const index_type* gko::batch::preconditioner::Jacobi< ValueType, IndexType >::get_const_blocks_cumulative_offsets ( ) const

inlinenoexcept

Returns the cumulative blocks storage array.

Note

Returns nullptr in case of a scalar jacobi preconditioner (max_block_size = 1).

References gko::array< ValueType >::get_const_data().

get_const_map_block_to_row()

template<typename ValueType = default_precision, typename IndexType = int32>

const index_type* gko::batch::preconditioner::Jacobi< ValueType, IndexType >::get_const_map_block_to_row ( ) const

inlinenoexcept

Returns the mapping between the blocks and the row id.

Note

Returns nullptr in case of a scalar jacobi preconditioner (max_block_size = 1).

References gko::array< ValueType >::get_const_data().

get_max_block_size()

template<typename ValueType = default_precision, typename IndexType = int32>

uint32 gko::batch::preconditioner::Jacobi< ValueType, IndexType >::get_max_block_size ( ) const

inlinenoexcept

Returns the max block size.

Returns

the max block size

References gko::batch::preconditioner::Jacobi< ValueType, IndexType >::parameters_type::max_block_size.

get_num_blocks()

template<typename ValueType = default_precision, typename IndexType = int32>

size_type gko::batch::preconditioner::Jacobi< ValueType, IndexType >::get_num_blocks ( ) const

inlinenoexcept

Returns the number of blocks in an individual batch entry.

Returns

the number of blocks in an individual batch entry.

get_num_stored_elements()

template<typename ValueType = default_precision, typename IndexType = int32>

size_type gko::batch::preconditioner::Jacobi< ValueType, IndexType >::get_num_stored_elements ( ) const

inlinenoexcept

Returns the number of elements explicitly stored in the dense blocks.

Note

Returns 0 in case of scalar jacobi preconditioner as the preconditioner is generated inside the batched solver kernels, hence, blocks array storage is not required.

Returns

the number of elements explicitly stored in the dense blocks.

References gko::array< ValueType >::get_size().

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

• ginkgo/core/preconditioner/batch_jacobi.hpp