[MAHOUT-1717] allreduceBlock operator api and Spark implementation

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.10.2
• Assignee: Dmitriy Lyubimov
• Reporter: Dmitriy Lyubimov
• Created: 02/Jun/15 23:05
• Updated: 07/Aug/15 15:56
• Resolved: 17/Jun/15 19:00

Description

need it surprisingly often.

allreduceMap ( map: (keys, Matrix) => Matrix, reduce: (Matrix, Matrix) => Matrix) : Matrix

again since we cannot guarantee we'd ask engines to serialize any type, we operate on types we do know will work (I.e. matrix blocks).

PR: https://github.com/apache/mahout/pull/135