Others will know better if it is implemented or not, but it shouldn't be too 
hard to implement if it isn't, since the sign of a permutation s is just 
(-1)**N(s), where N(s) is the number of inversions in s.  See 
http://mathworld.wolfram.com/PermutationInversion.html and 
http://mathworld.wolfram.com/InversionVector.html.  Alternately, you could 
compute a transposition decomposition of the permutation.  I am not sure which 
one of these is more efficient, or easier to implement.  And it's trivial to 
check if a given tuple of integers a1,…,,an is a permutation from S(n).  

Aaron Meurer

On Feb 11, 2011, at 11:01 AM, Dox wrote:

> Hi guys!
> 
> Short question! Is there any function equivalent to the Levi-Civita symbol?
> 
> I found Eijk... but seems to work only in 3-dimensions.
> 
> Thank you!
> 
> Dox

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