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https://issues.apache.org/jira/browse/MATH-867?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13466319#comment-13466319
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Nikolaus Hansen commented on MATH-867:
--------------------------------------

{quote}
I would like to, but as I said, the identity transformation makes one of the 
tests fail.
It must be because something else in the code assumes that the parameters have 
been restricted into the [0, 1] interval, which is not true anymore.
{quote}
The reason is IMHO line 589, which does need to be changed according to the 
change in encode/decode. 

{quote}
I wonder whether the various matrices (around lines 380) are computed based on 
this assumption...
{quote}
I would not worry much, I am pretty sure they are not. 

                
> CMAESOptimizer with bounds fits finely near lower bound and coarsely near 
> upper bound. 
> ---------------------------------------------------------------------------------------
>
>                 Key: MATH-867
>                 URL: https://issues.apache.org/jira/browse/MATH-867
>             Project: Commons Math
>          Issue Type: Bug
>            Reporter: Frank Hess
>         Attachments: MATH867_patch, Math867Test.java
>
>
> When fitting with bounds, the CMAESOptimizer fits finely near the lower bound 
> and coarsely near the upper bound.  This is because it internally maps the 
> fitted parameter range into the interval [0,1].  The unit of least precision 
> (ulp) between floating point numbers is much smaller near zero than near one. 
>  Thus, fits have much better resolution near the lower bound (which is mapped 
> to zero) than the upper bound (which is mapped to one).  I will attach a 
> example program to demonstrate.

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