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 the special KSPNASH, KSPSTCG, and KSPGLTR solvers which are used by the SNESNEWTONTR (trust region) solver.