**reason ** -negative value indicates diverged, positive value converged, see KSPConvergedReason

Possible values for reason: See also manual page for each reason

KSP_CONVERGED_RTOL (residual 2-norm decreased by a factor of rtol, from 2-norm of right hand side)

KSP_CONVERGED_ATOL (residual 2-norm less than abstol)

KSP_CONVERGED_ITS (used by the preonly preconditioner that always uses ONE iteration, or when the KSPConvergedSkip() convergence test routine is set.

KSP_CONVERGED_CG_NEG_CURVE

KSP_CONVERGED_CG_CONSTRAINED

KSP_CONVERGED_STEP_LENGTH

KSP_DIVERGED_ITS (required more than its to reach convergence)

KSP_DIVERGED_DTOL (residual norm increased by a factor of divtol)

KSP_DIVERGED_NANORINF (residual norm became Not-a-number or Inf likely due to 0/0)

KSP_DIVERGED_BREAKDOWN (generic breakdown in method)

KSP_DIVERGED_BREAKDOWN_BICG (Initial residual is orthogonal to preconditioned initial residual. Try a different preconditioner, or a different initial Level.)

Notes: Can only be called after the call the KSPSolve() is complete.

### Keywords

KSP, nonlinear, set, convergence, test

### See Also

KSPSetConvergenceTest(), KSPConvergedDefault(), KSPSetTolerances(), KSPConvergedReason

**Level:**intermediate

Location:src/ksp/ksp/interface/iterativ.c

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

src/ksp/ksp/examples/tutorials/ex10.c.html