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https://issues.apache.org/jira/browse/MATH-1300?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15065584#comment-15065584
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Phil Steitz commented on MATH-1300:
-----------------------------------

I am not sure that I buy the fact that this is a bug.  We don't advertise this 
invariant and I don't see the need to constrain implementations to satisfy it.  
Unless I am misunderstanding, we *do* provide seed-consistency with constant 
output buffer size and that is what practical implementations should depend on. 
 Is there a practical use case that requires the invariant asked for in this 
issue?

> 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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