[Octopus-users] How to evaluate the exponential of a non-hermitian matrix

[Miguel Marques]

  Hi,

  The best reference is:

Nineteen dubious ways to compute the exponencial of a matrix, twenty-five
years later
Cleve Moler and Charles Van Loan
SIAM Review 45 No 1, pp 3-49

  If youbhave problems getting the article, please ask alberto
(alberto_dot_castro_at_tddft_dot_org).

  cheers,
  miguel

P.S. If you implement any of the methdos not included in opctopus, would
you mind sending the coed to us, so that we include it in the code?

On Mon, 30 Aug 2004, Nam A. Nguyen wrote:

> Hi octopus users,
>
> I want to calculate the exponential of a non-hermitian matrix.
> Unfortunately there's no way that I can decompose it into a sum of
> several hermitian matrices. I use matexp
> (method=scaleandsquare)subroutine but my calculation doesn't seem to
> converge.
>
> My questions are:
>
> How to test the reliability of matexp ?
> Is there any better method ?
>
> My martix is very small, just 2x2
>
> Best regards
> Nam
>
> _______________________________________________
> Octopus-users mailing list
> Octopus-users at tddft.org
> http://www.tddft.org/mailman/listinfo/octopus-users
>