PCFactorSetShiftAmount#

adds a quantity to the diagonal of the matrix during numerical factorization, thus the matrix has nonzero pivots

Synopsis#

#include "petscpc.h" 
PetscErrorCode PCFactorSetShiftAmount(PC pc, PetscReal shiftamount)

Logically Collective

Input Parameters#

  • pc - the preconditioner context

  • shiftamount - amount of shift or PETSC_DECIDE for the default

Options Database Key#

  • -pc_factor_shift_amount - Sets shift amount or -1 for the default

See Also#

PCCHOLESKY, PCLU, ``PCFactorSetZeroPivot(), PCFactorSetShiftType()`

Level#

intermediate

Location#

src/ksp/pc/impls/factor/factor.c

Implementations#

PCFactorSetShiftAmount_Factor in src/ksp/pc/impls/factor/factimpl.c


Edit on GitLab

Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages