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https://issues.apache.org/jira/browse/MAHOUT-687?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13030289#comment-13030289
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Ted Dunning commented on MAHOUT-687:
------------------------------------

{quote}
Why should the default creator of a random number generator include a system 
call to the random seed operating system device driver?
{quote}
Because it provides good seeds from real physical processes?


> Random generator objects- slight refactor
> -----------------------------------------
>
>                 Key: MAHOUT-687
>                 URL: https://issues.apache.org/jira/browse/MAHOUT-687
>             Project: Mahout
>          Issue Type: Improvement
>            Reporter: Lance Norskog
>            Priority: Minor
>         Attachments: MAHOUT-687.patch
>
>
> Problems:
> * Uncommons MersenneTwisterRNG, the default RandomUtils.getRandom(), ignores 
> setSeed without throwing an error.
> * The project wants to move off Uncommons anyway.
> This patch uses the org.apache.commons.math.random.RandomGenerator classes 
> instead of org.apache.uncommons.maths.RepeatableRNG classes.
> Testcases: All math test cases pass except for 
> org.apache.mahout.math.stats.LogLikelihoodTest. 
> Other package tests fail that are mostly about testing random-oriented 
> classes; not a surprise.
> Almost all tests that use random numbers in algorithms still pass; this is a 
> good sign of their stability.
> .
> Still, a lot of tests have to be fiddled to make this commit.

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