I think switching the sort order would probably
break a fair amount of code, and it wouldn't
necessarily be obvious that it had been broken.
For example, I suspect that there is a fair amount
of code that tests if all eigenvalues are positive by
just looking at the last one.  

Anyway, consistency is the hobgoblin of small minds.


Patrick Burns

Burns Statistics
[EMAIL PROTECTED]
+44 (0)20 8525 0696
http://www.burns-stat.com
(home of S Poetry and "A Guide for the Unwilling S User")

Peter Dalgaard wrote:

>Prof Brian Ripley <[EMAIL PROTECTED]> writes:
>
>  
>
>>That is not a symmetric matrix so the eigenvalues are potentially complex 
>>and are sorted by modulus.  There's an ambiguity in the description for 
>>that case.
>>    
>>
>
>Ah-ha! Thanks, Brian. 
>
>I wonder if we should switch to sorting by absolute value in the real
>case too, for consistency, and maybe also to avoid silly mistakes
>caused by people expecting that the first/last eigenvalues are the
>important ones.
>
>  
>


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