# Package org.apache.sysds.runtime.compress.readers

- Class Summary
  Class | Description
  --- | ---
  ReaderColumnSelection | Base class for all column selection readers.
  ReaderColumnSelectionBitSet |
  ReaderColumnSelectionDenseMultiBlock |
  ReaderColumnSelectionDenseMultiBlockTransposed |
  ReaderColumnSelectionDenseSingleBlock |
  ReaderColumnSelectionDenseSingleBlockTransposed |
  ReaderColumnSelectionSparse | Used to extract the values at certain indexes from each row in a sparse matrix Keeps returning all-zeros arrays until reaching the last possible index.
  ReaderColumnSelectionSparseTransposed | Used to extract the values at certain indexes from each row in a sparse matrix Keeps returning all-zeros arrays until reaching the last possible index.
  ReaderCompressedSelection |

Copyright © 2021 The Apache Software Foundation. All rights reserved.