Uploaded image for project: 'Commons Math'
  1. Commons Math
  2. MATH-585

Very slow generation of gamma random variates

    XMLWordPrintableJSON

Details

    • Improvement
    • Status: Closed
    • Major
    • Resolution: Fixed
    • 2.2, 3.0
    • 3.0
    • None
    • All

    Description

      The current implementation of gamma random variate generation works, but uses an inversion method. This is well-known to be a bad idea. Usually a carefully constructed rejection procedure is used. To give an idea of the magnitude of the problem, the Gamma variate generation in Parallel COLT is roughly 50 times faster than in Commons Math.

      Attachments

        1. MATH585-1.patch
          15 kB
          Mikkel Meyer Andersen
        2. MATH585-4-gamma.patch
          17 kB
          Mikkel Meyer Andersen
        3. MATH585-MT2001-1.patch
          5 kB
          Mikkel Meyer Andersen

        Activity

          People

            mikl Mikkel Meyer Andersen
            darrenjw Darren Wilkinson
            Votes:
            0 Vote for this issue
            Watchers:
            0 Start watching this issue

            Dates

              Created:
              Updated:
              Resolved:

              Time Tracking

                Estimated:
                Original Estimate - 6h
                6h
                Remaining:
                Remaining Estimate - 6h
                6h
                Logged:
                Time Spent - Not Specified
                Not Specified