PCAIRSetALump

Sets whether PCAIR lumps to the diagonal rather than drops when forming the coarse matrix

Synopsis

PETSC_EXTERN PetscErrorCode PCAIRSetALump(PC pc, PetscBool input_bool)

Logically Collective

Input Parameters

• pc - the PCAIR preconditioner context

• input_bool - PETSC_TRUE to lump to the diagonal rather than drop when forming the coarse matrix

Options Database Key

• -pc_air_a_lump (true|false) - lump to the diagonal rather than drop for the coarse matrix; defaults to false

Note

When dropping entries from the coarse matrix (see PCAIRSetADrop()), enabling this adds each dropped entry onto the diagonal instead of discarding it, which preserves row sums and can improve convergence.

See Also

KSP: Linear System Solvers, PCAIR, PCAIRGetALump(), PCAIRSetADrop()

Level

advanced

Index of all PC routines
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Index of all manual pages