Mahout
  1. Mahout
  2. MAHOUT-310

LanczosSolver and DistributedLanczosSolver always assume rectangular input, but should also handle symmetric eigensystems.

    Details

    • Type: Improvement Improvement
    • Status: Closed
    • Priority: Major Major
    • Resolution: Fixed
    • Affects Version/s: 0.3
    • Fix Version/s: 0.3
    • Component/s: None
    • Labels:
      None

      Description

      LanczosSolver calls inputMatrix.timesSquared(Vector) as it's Krylov iteration, but for symmetric inputMatrix, it should chose to instead call inputMatrix.times(Vector).

      Similarly for DistributedLanczosSolver, except in this case, DistributedSparseRowMatrix actually needs to properly MapReduce implement times(Vector) for this to work (which it should do anyways, instead of throw UnsupportedOperationException as it does currently).

      1. MAHOUT-lots.diff
        56 kB
        Jake Mannix
      2. MAHOUT-310.patch
        21 kB
        Jake Mannix

        Activity

        Hide
        Jake Mannix added a comment -

        Patch has newly modified unit tests to test the symmetric case, and they pass (both for LanczosSolver and DistributedLanczosSolver). This has not been tested on large sparse symmetric matrices for performance yet, as I don't have any such data sets to try it out on right now.

        Show
        Jake Mannix added a comment - Patch has newly modified unit tests to test the symmetric case, and they pass (both for LanczosSolver and DistributedLanczosSolver). This has not been tested on large sparse symmetric matrices for performance yet, as I don't have any such data sets to try it out on right now.
        Hide
        Jake Mannix added a comment -

        I hope we get this release out soon, I've got a giant pile of code burning a hole in my laptop.

        Current patch fixes this ticket as well as MAHOUT-312, MAHOUT-313, and MAHOUT-314 (unit tests included)

        Show
        Jake Mannix added a comment - I hope we get this release out soon, I've got a giant pile of code burning a hole in my laptop. Current patch fixes this ticket as well as MAHOUT-312 , MAHOUT-313 , and MAHOUT-314 (unit tests included)
        Hide
        Jake Mannix added a comment -

        committed

        Show
        Jake Mannix added a comment - committed

          People

          • Assignee:
            Jake Mannix
            Reporter:
            Jake Mannix
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            Dates

            • Created:
              Updated:
              Resolved:

              Development