KSPConvergedReason

reason a Krylov method was determined to have converged or diverged

Synopsis

typedef enum { /* converged */
  KSP_CONVERGED_RTOL_NORMAL               = 1,
  KSP_CONVERGED_ATOL_NORMAL               = 9,
  KSP_CONVERGED_RTOL                      = 2,
  KSP_CONVERGED_ATOL                      = 3,
  KSP_CONVERGED_ITS                       = 4,
  KSP_CONVERGED_NEG_CURVE                 = 5,
  KSP_CONVERGED_CG_NEG_CURVE_DEPRECATED   = 5,
  KSP_CONVERGED_CG_CONSTRAINED_DEPRECATED = 6,
  KSP_CONVERGED_STEP_LENGTH               = 6,
  KSP_CONVERGED_HAPPY_BREAKDOWN           = 7,
  /* diverged */
  KSP_DIVERGED_NULL                      = -2,
  KSP_DIVERGED_ITS                       = -3,
  KSP_DIVERGED_DTOL                      = -4,
  KSP_DIVERGED_BREAKDOWN                 = -5,
  KSP_DIVERGED_BREAKDOWN_BICG            = -6,
  KSP_DIVERGED_NONSYMMETRIC              = -7,
  KSP_DIVERGED_INDEFINITE_PC             = -8,
  KSP_DIVERGED_NANORINF                  = -9,
  KSP_DIVERGED_INDEFINITE_MAT            = -10,
  KSP_DIVERGED_PC_FAILED                 = -11,
  KSP_DIVERGED_PCSETUP_FAILED_DEPRECATED = -11,

  KSP_CONVERGED_ITERATING = 0
} KSPConvergedReason;

Values

• KSP_CONVERGED_RTOL_NORMAL - requested decrease in the residual for the normal equations

• KSP_CONVERGED_ATOL_NORMAL - requested absolute value in the residual for the normal equations

• KSP_CONVERGED_RTOL - requested decrease in the residual

• KSP_CONVERGED_ATOL - requested absolute value in the residual

• KSP_CONVERGED_ITS - requested number of iterations

• KSP_CONVERGED_NEG_CURVE - see note below

• KSP_CONVERGED_STEP_LENGTH - see note below

• KSP_CONVERGED_HAPPY_BREAKDOWN - happy breakdown (meaning early convergence of the KSPType occurred).

• KSP_DIVERGED_NULL - breakdown when solving the Hessenberg system within GMRES

• KSP_DIVERGED_ITS - requested number of iterations

• KSP_DIVERGED_DTOL - large increase in the residual norm

• KSP_DIVERGED_BREAKDOWN - breakdown in the Krylov method

• KSP_DIVERGED_BREAKDOWN_BICG - breakdown in the KSPBGCS Krylov method

• KSP_DIVERGED_NONSYMMETRIC - the operator or preonditioner was not symmetric for a KSPType that requires symmetry

• KSP_DIVERGED_INDEFINITE_PC - the preconditioner was indefinite for a KSPType that requires it be definite

• KSP_DIVERGED_NANORINF - a not a number of infinity was detected in a vector during the computation

• KSP_DIVERGED_INDEFINITE_MAT - the operator was indefinite for a KSPType that requires it be definite

• KSP_DIVERGED_PC_FAILED - the action of the preconditioner failed for some reason

Note

The values KSP_CONVERGED_NEG_CURVE, and KSP_CONVERGED_STEP_LENGTH are returned only by KSPCG, KSPMINRES and by the special KSPNASH, KSPSTCG, and KSPGLTR solvers which are used by the SNESNEWTONTR (trust region) solver.

Developer Note

The string versions of these are KSPConvergedReasons; if you change any of the values here also change them that array of names.

See Also

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

Level

beginner

Location

include/petscksp.h

Examples

src/ksp/ksp/tutorials/ex87.c
src/dm/impls/stag/tutorials/ex4.c
src/snes/tutorials/ex6.c
src/ksp/ksp/tutorials/ex77.c
src/dm/impls/stag/tutorials/ex8.c
src/ksp/ksp/tutorials/ex72.c
src/ksp/ksp/tutorials/ex59.c
src/ksp/pc/tutorials/ex1.c
src/ksp/ksp/tutorials/ex76.c
src/ksp/pc/tutorials/ex2.c

---

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