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 or MATORDERINGRCM

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.

Level#

intermediate

Location#

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

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