petsc-3.7.1 2016-05-15
PCSetModifySubMatrices
Sets a user-defined routine for modifying the submatrices that arise within certain subdomain-based preconditioners. The basic submatrices are extracted from the preconditioner matrix as usual; the user can then alter these (for example, to set different boundary conditions for each submatrix) before they are used for the local solves.
Synopsis
#include "petscksp.h"
PetscErrorCode PCSetModifySubMatrices(PC pc,PetscErrorCode (*func)(PC,PetscInt,const IS[],const IS[],Mat[],void*),void *ctx)
Logically Collective on PC Many br
Input Parameters
| pc | - the preconditioner context Many br |
| func | - routine for modifying the submatrices Many br |
| ctx | - optional user-defined context (may be null) Many br |
Calling sequence of func
func (PC pc,PetscInt nsub,IS *row,IS *col,Mat *submat,void *ctx);
row -an array of index sets that contain the global row numbers Many brthat comprise each local submatrix Many br
col -an array of index sets that contain the global column numbers Many brthat comprise each local submatrix Many br
submat -array of local submatrices Many br
ctx -optional user-defined context for private data for the Many bruser-defined func routine (may be null) Many br
Notes
PCSetModifySubMatrices() MUST be called before KSPSetUp() and Many brKSPSolve(). Many br
A routine set by PCSetModifySubMatrices() is currently called within Many brthe block Jacobi (PCBJACOBI) and additive Schwarz (PCASM) Many brpreconditioners. All other preconditioners ignore this routine. Many br
Many br
Keywords
PC, set, modify, submatrices
See Also
PCModifySubMatrices(), PCASMGetSubMatrices()
Level:advanced
Location:src/ksp/pc/interface/precon.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages