KSPFETIDPSetPressureOperator#

Sets the operator used to set up the pressure preconditioner for the saddle point KSPFETIDP solver,

Synopsis#

#include <petscksp.h> 
PetscErrorCode KSPFETIDPSetPressureOperator(KSP ksp, Mat P)

Collective

Input Parameters#

ksp - the KSPFETIDP solver
P - the linear operator to be preconditioned, usually the mass matrix.

Notes#

The operator can be either passed in a) monolithic global ordering, b) pressure-only global ordering or c) interface pressure ordering (if -ksp_fetidp_pressure_all false). In cases b) and c), the pressure ordering of dofs needs to satisfy pid_1 < pid_2 iff gid_1 < gid_2 where pid_1 and pid_2 are two different pressure dof numbers and gid_1 and gid_2 the corresponding id in the monolithic global ordering.