Larger part of mahout-math is linear algebra, which is currently broken for sparse part of the equation and which we don't use at all.
One part of the problem is that our use for that library is always a fringe case, and as far as i can tell, will always continue to be such. Another part of the problem is that keeping dependency will invite bypassing Mahout's solvers and, as a result, architecture inconsistency. That said, I guess Ted's argument (which is mainly cost, as i gathered), trumps the two above. On Mon, Aug 12, 2013 at 3:20 PM, Peng Cheng <[email protected]> wrote: > seriously, I would prefer the dependency as a good architectural pattern. > It encourages other people to use/contribute to it to avoid repetitive work. > > > On 13-08-12 06:16 PM, Ted Dunning wrote: > >> I am fine with it staying. >> >> >> On Mon, Aug 12, 2013 at 3:14 PM, Dmitriy Lyubimov <[email protected]> >> wrote: >> >> So you are ok with apache-math dependency to stay? >>> >>> >>> On Mon, Aug 12, 2013 at 3:09 PM, Ted Dunning <[email protected]> >>> wrote: >>> >>> So I checked on these. The non-trivial issues with replacing Commons >>>> >>> Math >>> >>>> include: >>>> >>>> - Poisson and negative binomial distributions. This would be several >>>> >>> hours >>> >>>> work to write and test (we have Colt-inherited negative binomial >>>> distribution, but it takes no longer to write a new one than to test an >>>> >>> old >>> >>>> one). >>>> >>>> - random number generators. This is about and hour or two of work to >>>> >>> pull >>> >>>> the MersenneTwister implementation into our code. >>>> >>>> - next prime number finder. Not a big deal to replicate, but it would >>>> >>> take >>> >>>> a few hours to do. >>>> >>>> - quadrature. We use an adaptive integration routine to check >>>> >>> distribution >>> >>>> properties. This, again, would take a few hours to replace. >>>> >>>> I really don't see the benefit to this work. >>>> >>>> On Mon, Aug 12, 2013 at 2:53 PM, Ted Dunning <[email protected]> >>>> wrote: >>>> >>>> 2 distribution.**PoissonDistribution; >>>>> 2 distribution.**PascalDistribution; >>>>> 2 distribution.**NormalDistribution; >>>>> 1 util.FastMath; >>>>> 1 random.RandomGenerator; >>>>> 1 random.MersenneTwister; >>>>> 1 primes.Primes; >>>>> 1 linear.RealMatrix; >>>>> 1 linear.EigenDecomposition; >>>>> 1 linear.Array2DRowRealMatrix; >>>>> 1 distribution.RealDistribution; >>>>> 1 distribution.**IntegerDistribution; >>>>> 1 analysis.integration.**UnivariateIntegrator; >>>>> 1 analysis.integration.**RombergIntegrator; >>>>> 1 analysis.UnivariateFunction; >>>>> >>>>> > >
