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| From | Eric Sosman <esosman@ieee-dot-org.invalid> |
| Newsgroups | comp.lang.java.programmer |
| Subject | Re: RandomDirichlet? |
| Date | Tue, 01 Nov 2011 07:50:01 -0400 |
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On 11/1/2011 5:09 AM, Giovanni Azua wrote:
> Hello,
>
> I need to generate random TPCH workloads but I don't want a Uniform
> distribution where Q1, RF1, RF2 would be equally probable i.e. using new
> Random().nextInt(..)
>
> I instead would like to draw samples from a Dirichlet distribution which
> would give a very skewed PD depending on the input alphas (which specify how
> skewed I want the PD to be). The Matlab code would be exactly:
>
> function r = dirichlet_sample(a,n)
> p = length(a);
> r = gamrnd(repmat(a,n,1),1,n,p);
> r = r ./ repmat(sum(r,2),1,p);
> End
>
> But there is no "gamrnd" RandomGamma in Java nor RandomDirichlet. Before I
> spend time writing this, can anyone advice for a low-footprint library
> implementing those functions?
Google finds ~114,000 hits for "gamma distribution java".
As an aside, Google finds ~396,000 hits for "dirichlet
distribution java".
Finally, Google finds ~111,000,000 hits for "people who
never heard of google". I'm not sure just what that means ...
--
Eric Sosman
esosman@ieee-dot-org.invalid
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RandomDirichlet? Giovanni Azua <bravegag@hotmail.com> - 2011-11-01 10:09 +0100
Re: RandomDirichlet? Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-01 07:50 -0400
Re: RandomDirichlet? Giovanni Azua <bravegag@hotmail.com> - 2011-11-01 19:50 +0100
Re: RandomDirichlet? Wojtek <nowhere@a.com> - 2011-11-01 04:54 -0700
Re: RandomDirichlet? Roedy Green <see_website@mindprod.com.invalid> - 2011-11-01 06:11 -0700
Re: RandomDirichlet? Roedy Green <see_website@mindprod.com.invalid> - 2011-11-01 06:16 -0700
Re: RandomDirichlet? Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-01 20:23 -0400
Re: RandomDirichlet? Roedy Green <see_website@mindprod.com.invalid> - 2011-11-02 01:39 -0700
Re: RandomDirichlet? Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-02 08:17 -0400
Re: RandomDirichlet? Arne Vajhøj <arne@vajhoej.dk> - 2011-11-01 22:09 -0400
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