PCCOMPOSITE#
Build a preconditioner by composing together several preconditioners
Options Database Keys#
-pc_composite_type <type: one of multiplicative, additive, symmetric_multiplicative, special> - Sets composite preconditioner type
-pc_use_amat - activates
PCSetUseAmat()-pc_composite_pcs - <pc0,pc1,…> list of PCs to compose
Notes#
To use a Krylov method inside the composite preconditioner, set the PCType of one or more
inner PCs to be PCKSP. Using a Krylov method inside another Krylov method can be dangerous (you get divergence or
the incorrect answer) unless you use KSPFGMRES as the outer Krylov method
To use a different operator to construct one of the inner preconditioners first call PCCompositeGetPC(), then
call PCSetOperators() on that PC.
See Also#
KSP: Linear System Solvers, PCCreate(), PCSetType(), PCType, PC,
PCSHELL, PCKSP, PCCompositeSetType(), PCCompositeSpecialSetAlpha(), PCCompositeAddPCType(),
PCCompositeGetPC(), PCSetUseAmat(), PCCompositeAddPC(), PCCompositeGetNumberPC()
Level#
intermediate
Location#
Examples#
src/ksp/pc/tutorials/ex4.c
src/ksp/ksp/tutorials/ex71.c
src/ksp/ksp/tutorials/ex60.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages