# Package org.apache.sysds.runtime.data

- Class Summary
  Class | Description
  --- | ---
  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
  Enum | Description
  --- | ---
  DenseBlock.Type |
  SparseBlock.Type |