PCCHOLESKY#

Uses a direct solver, based on Cholesky factorization, as a preconditioner

Options Database Keys#

  • -pc_factor_reuse_ordering - Activate PCFactorSetReuseOrdering()

  • -pc_factor_mat_solver_type - Actives PCFactorSetMatSolverType() to choose the direct solver, like superlu

  • -pc_factor_reuse_fill - Activates PCFactorSetReuseFill()

  • -pc_factor_fill - Sets fill amount

  • -pc_factor_in_place - Activates in-place factorization

  • -pc_factor_mat_ordering_type <nd,rcm,…> - Sets ordering routine

Notes#

Not all options work for all matrix formats

Usually this will compute an “exact” solution in one iteration and does not need a Krylov method (i.e. you can use -ksp_type preonly, or KSPSetType(ksp,KSPPREONLY) for the Krylov method

See Also#

PCCreate(), PCSetType(), PCType, PC, PCILU, PCLU, PCICC, PCFactorSetReuseOrdering(), PCFactorSetReuseFill(), PCFactorGetMatrix(), PCFactorSetFill(), PCFactorSetShiftNonzero(), PCFactorSetShiftType(), PCFactorSetShiftAmount() PCFactorSetUseInPlace(), PCFactorGetUseInPlace(), PCFactorSetMatOrderingType(), PCFactorSetReuseOrdering()

Level#

beginner

Location#

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

Examples#

src/ksp/ksp/tutorials/ex52.c
src/ksp/ksp/tutorials/ex57f.F90
src/tao/constrained/tutorials/ex1.c

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