fipy.solvers.petsc.petscConvergence

Classes

KSP_AbsoluteToleranceConvergence(solver, ...)	Residual 2-norm less than abstol
KSP_BreakdownBICGDivergence(solver, ...[, ...])	Initial residual is orthogonal to preconditioned initial residual.
KSP_BreakdownDivergence(solver, iterations, ...)	Generic breakdown in method.
KSP_HappyBreakdownConvergence(solver, ...[, ...])
KSP_IndefiniteMatrixDivergence(solver, ...)
KSP_IndefinitePreconditionerDivergence(...)	It appears the preconditioner is indefinite (has both positive and negative eigenvalues) and this Krylov method (KSPCG) requires it to be positive definite.
KSP_IteratingConvergence(solver, iterations, ...)	This flag is returned if you call KSPGetConvergedReason() while the KSPSolve() is still running.
KSP_IterationConvergence(solver, iterations, ...)	Used by the KSPPREONLY solver after the single iteration of the preconditioner is applied.
KSP_IterationDivergence(solver, iterations, ...)	Ran out of iterations before any convergence criteria was reached
KSP_NanOrInfDivergence(solver, iterations, ...)	Residual norm became Not-a-number or Inf likely due to 0/0.
KSP_NonSymmetricDivergence(solver, ...[, ...])	It appears the operator or preconditioner is not symmetric and this Krylov method (KSPCG, KSPMINRES, KSPCR) requires symmetry
KSP_NormalAbsoluteToleranceConvergence(...)
KSP_NormalRelativeToleranceConvergence(...)
KSP_NullDivergence(solver, iterations, ...)
KSP_PreconditioningDivergence(solver, ...[, ...])	It was not possible to build or use the requested preconditioner.
KSP_RelativeToleranceConvergence(solver, ...)	Residual 2-norm decreased by a factor of rtol, from 2-norm of right hand side.
KSP_ToleranceDivergence(solver, iterations, ...)	Residual norm increased by a factor of divtol.

class fipy.solvers.petsc.petscConvergence.KSP_AbsoluteToleranceConvergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: AbsoluteToleranceConvergence

Residual 2-norm less than abstol

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_BreakdownBICGDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: KSP_BreakdownDivergence

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

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_BreakdownDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: BreakdownDivergence

Generic breakdown in method.

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_HappyBreakdownConvergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: HappyBreakdownConvergence

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_IndefiniteMatrixDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: IllConditionedDivergence

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_IndefinitePreconditionerDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: IllConditionedPreconditionerDivergence

It appears the preconditioner is indefinite (has both positive and negative eigenvalues) and this Krylov method (KSPCG) requires it to be positive definite.

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_IteratingConvergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: IteratingConvergence

This flag is returned if you call KSPGetConvergedReason() while the KSPSolve() is still running.

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_IterationConvergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: IterationConvergence

Used by the KSPPREONLY solver after the single iteration of the preconditioner is applied. Also used when the KSPConvergedSkip() convergence test routine is set in KSP.

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_IterationDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: IterationDivergence

Ran out of iterations before any convergence criteria was reached

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_NanOrInfDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: OutOfRangeDivergence

Residual norm became Not-a-number or Inf likely due to 0/0.

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_NonSymmetricDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: IllConditionedDivergence

It appears the operator or preconditioner is not symmetric and this Krylov method (KSPCG, KSPMINRES, KSPCR) requires symmetry

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_NormalAbsoluteToleranceConvergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: KSP_AbsoluteToleranceConvergence

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_NormalRelativeToleranceConvergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: KSP_RelativeToleranceConvergence

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_NullDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: NullDivergence

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_PreconditioningDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: PreconditioningDivergence

It was not possible to build or use the requested preconditioner. This is usually due to a zero pivot in a factorization. It can also result from a failure in a subpreconditioner inside a nested preconditioner such as PCFIELDSPLIT.

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_RelativeToleranceConvergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: RelativeToleranceConvergence

Residual 2-norm decreased by a factor of rtol, from 2-norm of right hand side.

__str__()

Return str(self).

class fipy.solvers.petsc.petscConvergence.KSP_ToleranceDivergence(solver, iterations, residual, criterion, actual_code=None, **kwargs)

Bases: ToleranceDivergence

Residual norm increased by a factor of divtol.

__str__()

Return str(self).

Last updated on Sep 16, 2025. Created using Sphinx 7.1.2.