HanaHalitim opened a new pull request, #2361: URL: https://github.com/apache/systemds/pull/2361
Implemented delta encoding compression for SystemDS. Added ColGroupDeltaDDC compression type that stores row differences instead of absolute values, improving compression for data with predictable patterns. Created delta readers that compute row differences on-the-fly during compression, avoiding delta matrix materialization. Wired CUMSUM and ROWCUMSUM operations to automatically use delta encoding for their results. Extended compression estimation with preferDeltaEncoding flag to evaluate delta encoding as a compression option. Fixed dictionary remapping bug where extractValues() reordered entries, breaking row-to-dictionary mappings. All tests pass including ColGroupDeltaDDCTest, CLALibUnaryDeltaTest, ReadersDeltaTest, and related compression tests. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
