PCExoticSetType#
Sets the type of coarse grid interpolation to use
Synopsis#
#include "petscdmda.h"
#include "petscksp.h"
PetscErrorCode PCExoticSetType(PC pc, PCExoticType type)
Logically Collective
Input Parameters#
pc - the preconditioner context
type - either
PC_EXOTIC_FACE
orPC_EXOTIC_WIREBASKET
(defaults to face)
Options Database Keys#
-pc_exotic_type <face,wirebasket> - use a coarse grid point for each face, or edge and vertex
Notes#
The face based interpolation has 1 degree of freedom per face and ignores the edge and vertex values completely in the coarse problem. For any seven point stencil the interpolation of a constant on all faces into the interior is that constant.
The wirebasket interpolation has 1 degree of freedom per vertex, per edge and per face. A constant on the subdomain boundary is interpolated as that constant in the interior of the domain.
The coarse grid matrix is obtained via the Galerkin computation \(A_c = R A R^T\), hence if \(A\) is nonsingular \(A_c\) is also nonsingular.
Both interpolations are suitable for only scalar problems.
See Also#
Level#
intermediate
Location#
Implementations#
PCExoticSetType_Exotic() in src/ksp/pc/impls/wb/wb.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages