# Package org.apache.sysds.runtime.data

Class Summary
BasicTensorBlock
DataTensorBlock
DenseBlock: This DenseBlock is an abstraction for different dense, row-major matrix formats.
DenseBlockBool
DenseBlockDRB
DenseBlockFactory
DenseBlockFP32
DenseBlockFP64
DenseBlockInt32
DenseBlockInt64
DenseBlockLBool
DenseBlockLDRB: Dense Large Row Blocks have multiple 1D arrays (blocks), which contain complete rows.
DenseBlockLFP32
DenseBlockLFP64
DenseBlockLInt32
DenseBlockLInt64
DenseBlockLString
DenseBlockString
IndexedTensorBlock
LibTensorAgg
LibTensorBincell
LibTensorReorg
SparseBlock: This SparseBlock is an abstraction for different sparse matrix formats.
SparseBlockCOO: SparseBlock implementation that realizes a traditional 'coordinate matrix' representation, where the entire sparse block is stored as triples in three arrays: row indexes, column indexes, and values, where row indexes and colunm indexes are sorted in order to allow binary search.
SparseBlockCSR: SparseBlock implementation that realizes a traditional 'compressed sparse row' representation, where the entire sparse block is stored as three arrays: ptr of length rlen+1 to store offsets per row, and indexes/values of length nnz to store column indexes and values of non-zero entries.
SparseBlockFactory

SparseBlockMCSR

SparseBlock implementation that realizes a 'modified compressed sparse row' representation, where each compressed row is stored as a separate SparseRow object which provides flexibility for unsorted row appends without the need for global reshifting of values/indexes but it incurs additional memory overhead per row for object/array headers per row which also slows down memory-bound operations due to higher memory bandwidth requirements.

SparseRow: Base class for sparse row implementations such as sparse row vectors and sparse scalars (single value per row).
SparseRowScalar
SparseRowVector
TensorBlock: A `TensorBlock` is the most top level representation of a tensor.
TensorIndexes: This represent the indexes to the blocks of the tensor.

Enum Summary
DenseBlock.Type
SparseBlock.Type