[petsc-users] SLEPc: Setting options for mass matrix KSP in generalised eigenvalue problem

[Jose E. Roman]

This case is treated in the same way as the (shift-and-invert) spectral transformation. There are nested objects EPS > ST > KSP > PC. By default ST=SHIFT, which is what you need. So you just have to get access to the KSP/PC objects to set options.

Basically you can use ex9.py in slepc4py but use F.setType(F.Type.SHIFT) instead of F.setType(F.Type.PRECOND).

Jose


> El 16 ene 2019, a las 10:32, Cotter, Colin J via petsc-users <petsc-users at mcs.anl.gov> escribió:
> 
> Dear PETSc mailing list,
>   A SLEPc question, sorry if this is obvious and I missed something.
> 
> How do I set the KSP for the mass matrix M in the generalised eigenvalue problem
> (I'm looking for the eigenvalue with largest magnitude)
> 
> Ax = lambda*Mx
> 
> ?
> 
> I can only find how to set the KSP for a spectral transform. 
> 
> (I'm actually using slepc4py)
> 
> all the best
> -_Colin