KSP_DIVERGED_INDEFINITE_PC#

It appears the preconditioner is indefinite (has both positive and negative eigenvalues) and this Krylov method (KSPCG) requires it to be positive definite

Note#

This can happen with the PCICC preconditioner, use the options database option -pc_factor_shift_positive_definite to force the PCICC preconditioner to generate a positive definite preconditioner

See Also#

KSP: Linear System Solvers, KSPSolve(), KSPGetConvergedReason(), KSPConvergedReason, KSPSetTolerances()

Level#

beginner

Location#

include/petscksp.h

Examples#

src/ksp/pc/tutorials/ex1.c
src/ksp/pc/tutorials/ex2.c


Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages