You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@commons.apache.org by "Luc Maisonobe (JIRA)" <ji...@apache.org> on 2016/01/01 12:29:39 UTC

[jira] [Updated] (MATH-1300) BitsStreamGenerator#nextBytes(byte[]) is wrong

     [ https://issues.apache.org/jira/browse/MATH-1300?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Luc Maisonobe updated MATH-1300:
--------------------------------
    Fix Version/s: 3.6

> 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
>             Fix For: 3.6
>
>         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.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)