[petsc-users] EVP Solutions with Subspace

[Jose E. Roman]

El 05/04/2013, a las 18:43, Sonya Blade escribió:

>> http://www.grycap.upv.es/slepc/documentation/current/docs/manualpages/EPS/EPSSetDimensions.html
>> http://www.grycap.upv.es/slepc/documentation/current/docs/manualpages/EPS/EPSSetWhichEigenpairs.html
>> 
>> For these simple questions it is faster to look for the answer in the manual.
>> 
>> Jose
> 
> Sorry for that Jose,
> 
> The last message I received says that:
> [0]PETSC ERROR:   !
> [0]PETSC ERROR: KSP did not converge (reason=DIVERGED_ITS)!
> 
> What could be the reason of not convergence, due to the fact that B matrix has 
> some zero values on its diagonal? Is there any other methods which solves GEP 
> even if there is zeros on diagonals?
> 
> Regards, 		 	   		  

By default SLEPc uses a direct solver, so you would not get this message. Which options are you using for the KSP?

Jose