[petsc-users] SLEPc - st_type cayley choice of shift and antishift

[Michael Werner]

Hello,

I'm looking for advice on how to set shift and antishift for the cayley
spectral transformation. So far I've been using sinvert to find the
eigenvalues with the smallest real part (but possibly large imaginary
part). For this, I use the following options:
-st_type sinvert
-eps_target -0.05
-eps_target_real

With sinvert, it is easy to understand how to chose the target, but for
Cayley I'm not sure how to set shift and antishift. What is the
mathematical meaning of the antishift?

Best regards,
Michael Werner