[petsc-users] How to get the eigenvectors in Slepc

[Jose E. Roman]

El 14/04/2013, a las 08:04, Sonya Blade escribió:

> Dear All,
> 
> If I have all eigenvalues as real numbers is it possible mathematically that 
> I get the complex eigenvectors? Because nowhere in my solution I obtain the 
> complex eigenvalues but Slepc returns the complex for eigenvectors.
> 
> Your enlightenment will be appreciated.
> 
> Regards, 		 	   		  

If the eigenvector is complex then of course the eigenvalue is complex as well (I assume your matrix is real non-symmetric). You have to get both the real and imaginary parts of the eigenvalue.
http://www.grycap.upv.es/slepc/documentation/current/docs/manualpages/EPS/EPSGetEigenpair.html

An alternative is to do all the computation in complex arithmetic (configure --with-scalar-type=complex).

Jose