PCSPAISetEpsilon#
Set the tolerance for the PCSPAI preconditioner
Synopsis#
#include "petscpc.h"
PetscErrorCode PCSPAISetEpsilon(PC pc, PetscReal epsilon1)
Input Parameters#
pc - the preconditioner
epsilon1 - the tolerance (default .4)
Note#
espilon1 must be between 0 and 1. It controls the
quality of the approximation of M to the inverse of
A. Higher values of epsilon1 lead to more work, more
fill, and usually better preconditioners. In many
cases the best choice of epsilon1 is the one that
divides the total solution time equally between the
preconditioner and the solver.
See Also#
Level#
intermediate
Location#
Implementations#
PCSPAISetEpsilon_SPAI() in src/ksp/pc/impls/spai/ispai.c
Index of all PC routines
Table of Contents for all manual pages
Index of all manual pages