PCFieldSplitGetSubKSP#
Gets the KSP contexts for all splits
Synopsis#
#include "petscpc.h"
PetscErrorCode PCFieldSplitGetSubKSP(PC pc, PetscInt *n, KSP *subksp[])
Collective
Input Parameter#
pc - the preconditioner context
Output Parameters#
n - the number of splits
subksp - the array of
KSPcontexts
Notes#
After PCFieldSplitGetSubKSP() the array of KSPs is to be freed by the user with PetscFree()
(not the KSP, just the array that contains them).
You must call PCSetUp() before calling PCFieldSplitGetSubKSP().
If the fieldsplit is of type PC_COMPOSITE_SCHUR, it returns the KSP object used inside the
Schur complement and the KSP object used to iterate over the Schur complement.
To access all the KSP objects used in PC_COMPOSITE_SCHUR, use PCFieldSplitSchurGetSubKSP().
If the fieldsplit is of type PC_COMPOSITE_GKB, it returns the KSP object used to solve the
inner linear system defined by the matrix H in each loop.
Fortran Notes#
You must pass in a KSP array that is large enough to contain all the KSPs.
You can call PCFieldSplitGetSubKSP(pc,n,PETSC_NULL_KSP,ierr) to determine how large the
KSP array must be.
Developer Notes#
There should be a PCFieldSplitRestoreSubKSP() instead of requiring the user to call PetscFree()
The Fortran interface could be modernized to return directly the array of values.
See Also#
Solving Block Matrices with PCFIELDSPLIT, PC, PCFIELDSPLIT, PCFieldSplitSetFields(), PCFieldSplitSetIS(), PCFieldSplitSchurGetSubKSP()
Level#
advanced
Location#
Examples#
src/ksp/ksp/tutorials/ex27.c
src/ksp/ksp/tutorials/ex70.c
src/ksp/ksp/tutorials/ex87.c
src/snes/tutorials/ex70.c
src/ksp/ksp/tutorials/ex43.c
Implementations#
PCFieldSplitGetSubKSP_FieldSplit() in src/ksp/pc/impls/fieldsplit/fieldsplit.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages