Your advice isn't so bad even so. No need to reimplement interesting capabilities.
On Mon, Aug 12, 2013 at 4:56 PM, Peng Cheng <[email protected]> wrote: > Apologies, I mistaken apache-math as mahout-math and didn't know what I'm > talking about :) > > > On 13-08-12 07:08 PM, Ted Dunning wrote: > >> Yes. Apache Math linear algebra is very difficult for us to use because >> their matrices are non-extensible. >> >> But there is actually quite a lot of code to do with random distributions, >> optimization and quadrature. Those are much more likely to be useful to >> us. >> >> >> On Mon, Aug 12, 2013 at 3:26 PM, Dmitriy Lyubimov <[email protected]> >> wrote: >> >> 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; >>>>>>>> >>>>>>>> >>>>>>>> >>>> > >
