[Numpy-discussion] expm

[Nils Wagner]

On Fri, 20 Jul 2007 14:45:43 -0400
  "Kevin Jacobs <jacobs at bioinformed.com>" 
<bioinformed at gmail.com> wrote:
> On 7/20/07, Nils Wagner <nwagner at iam.uni-stuttgart.de> 
>wrote:
>>
>> Your sqrtm_eig(x) function won't work if x is defective.
>> See test_defective.py for details.
> 
> 
> I am aware, though at least on my system, the SVD-based 
>method is by far the
> fastest and robust (and can be made more robust by the 
>addition of a
> relative condition number threshold).  

Your sqrtm_svd(x) method also returns a wrong result,
if x is defective.

Cheers,

             Nils

The eig version
>was included mainly
> for comparison.
>