PCFactorSetMatOrderingType#
Sets the ordering routine (to reduce fill) to be used in the PCLU
, PCCHOLESKY
, PCILU
, or PCICC
preconditioners
Synopsis#
#include "petscpc.h"
PetscErrorCode PCFactorSetMatOrderingType(PC pc, MatOrderingType ordering)
Logically Collective
Input Parameters#
pc - the preconditioner context
ordering - the matrix ordering name, for example,
MATORDERINGND
orMATORDERINGRCM
Options Database Key#
-pc_factor_mat_ordering_type <nd,rcm,…,external> - Sets ordering routine
Notes#
Nested dissection is used by default for some of PETSc’s sparse matrix formats
For PCCHOLESKY
and PCICC
and the MATSBAIJ
format the only reordering available is natural since only the upper half of the matrix is stored
and reordering this matrix is very expensive.
You can use a MATSEQAIJ
matrix with Cholesky and ICC and use any ordering.
MATORDERINGEXTERNAL
means PETSc will not compute an ordering and the package will use its own ordering, usable with MATSOLVERCHOLMOD
, MATSOLVERUMFPACK
, and others.
See Also#
PCLU
, PCCHOLESKY
, PCILU
, PCICC
, MatOrderingType
, MATORDERINGEXTERNAL
, MATORDERINGND
, MATORDERINGRCM
Level#
intermediate
Location#
Implementations#
PCFactorSetMatOrderingType_Factor in src/ksp/pc/impls/factor/factimpl.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages