petsc-3.8.4 2018-03-24
Report Typos and Errors

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

Examples

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