Re: [Help-gsl] hi :-) \o/ I've some problem with eigensystem

[Giuseppe Marco Randazzo]

On Thursday 22 April 2010 10:20:39 tuc wrote:
> hi
> 
> > So the point of question is this: the
> > results that i get have the right values but the signs wrong.
> 
> let A be a square matrix. then a eigenvector v to the eigenvalue a is
> defined to have the property:
>      A*v=a*v.
> 
> therefor for any real number x (nonzero, zero is never an eigenvector)
> x*v is also a eigenvector of A:
>     A*(x*v)=x*(A*v)=x*(a*v)=a*(x*v)

ok!! i've read now the second example that say:

"Note that the eigenvectors can differ by a change of sign, since the sign of 
an eigenvector is arbitrary.

The following program illustrates the use of the nonsymmetric eigensolver,"

ok :) so with this example now the sings are ok! :-)


Thanks for support :-)