[petsc-users] Specifying different ksp_types for multiple linear systems

[Max Rudolph]

In my thermomechanical convection code, I set up and solve two linear systems, the first for the Stokes system and the second for an energy equation. Currently, these are separate matrices and during each timestep I first create a KSP object for each system, then solve, then destroy the KSP contexts. I would like to try out the -pc_type fieldsplit for the Stokes system, but is it possible to use -pc_type fieldsplit for the Stokes  system and different pc_type and ksp_type for the energy equation? Is there perhaps a way to name the KSP associated with the Stokes system and then refer to this label from the command line (e.g. -pc_type_0 fieldsplit -pc_type_1 lu) ? Thanks very much for your help.

Max Rudolph