PETSc version 3.15.5

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.

Level

intermediate

Location

src/ksp/pc/impls/composite/composite.c

Examples