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https://issues.apache.org/jira/browse/MATH-1300?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15065729#comment-15065729
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Luc Maisonobe commented on MATH-1300:
-------------------------------------
My position would be that even if having values independent of chunk size is a
nice features,
it is not worth degrading either understandability or performances for it. So
just advertising
the fact this property does *not* hold would be fine to me.
I'm also not sure losing much time with Mersenne twister is worth it. This
generator was the
best one a few years ago but has been superseded with the WELL family of
generators
almost 10 years ago (see http://www.iro.umontreal.ca/~panneton/WELLRNG.html,
where
a mink to the reference paper can be found). According to the paper, the
Mersenne twister
suffers fro a lack of chaos at the start (i.e. the first few millions
generations) that the WELL
generators fix.
> BitsStreamGenerator#nextBytes(byte[]) is wrong
> ----------------------------------------------
>
> Key: MATH-1300
> URL: https://issues.apache.org/jira/browse/MATH-1300
> Project: Commons Math
> Issue Type: Bug
> Affects Versions: 3.5
> Reporter: Rostislav Krasny
> Attachments: MersenneTwister2.java, TestMersenneTwister.java
>
>
> Sequential calls to the BitsStreamGenerator#nextBytes(byte[]) must generate
> the same sequence of bytes, no matter by chunks of which size it was divided.
> This is also how java.util.Random#nextBytes(byte[]) works.
> When nextBytes(byte[]) is called with a bytes array of length multiple of 4
> it makes one unneeded call to next(int) method. This is wrong and produces an
> inconsistent behavior of classes like MersenneTwister.
> I made a new implementation of the BitsStreamGenerator#nextBytes(byte[]) see
> attached code.
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