petsc-3.14.6 2021-03-30
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
Notes
This can happen with the PCICC preconditioner, use -pc_factor_shift_positive_definite to force
the PCICC preconditioner to generate a positive definite preconditioner
See Also
KSPSolve(), KSPGetConvergedReason(), KSPConvergedReason, KSPSetTolerances()
Level
beginner
Location
src/ksp/ksp/guess/../../../../include/petscksp.h
Examples
src/ksp/pc/tutorials/ex1.c.html
src/ksp/pc/tutorials/ex2.c.html
Index of all KSP routines
Table of Contents for all manual pages
Index of all manual pages