Nonlinear Solvers (SNES)

The Scalable Nonlinear Equations Solvers (SNES) component provides an easy-to-use interface to Newton-type, quasi-Newton, full approximation scheme (FAS) multigrid, and other methods for solving systems of nonlinear equations. User guide chapter: SNES: Nonlinear Solvers.

SNES internally employs KSP for the solution of its linear systems. SNES users can also set KSP options directly in application codes by first extracting the KSP context from the SNES context via SNESGetKSP() and then directly calling various KSP (and PC) routines,

Examples

Beginner - Basic usage

DMDASNESSetFunctionLocal DMDASNESSetFunctionLocalVec DMDASNESSetJacobianLocal DMDASNESSetJacobianLocalVec DMDASNESSetObjectiveLocal DMDASNESSetObjectiveLocalVec DMDASNESSetPicardLocal DMSNESGetFunctionLocal DMSNESGetJacobianLocal DMSNESGetObjectiveLocal PetscConvEstCreate PetscConvEstDestroy PetscConvEstSetFromOptions PetscConvEstSetUp PetscConvEstView SNES SNESANDERSON SNESCompositeType SNESConvergedReason SNESConvergedReasonView SNESCreate

SNESDestroy SNESFASType SNESFunctionFn SNESGetConvergedReasonString SNESGetKSP SNESGetLineSearch SNESInitialGuessFn SNESJacobianFn SNESKSPONLY SNESKSPTRANSPOSEONLY SNESLineSearch SNESLineSearchType SNESMULTIBLOCK SNESNCG SNESNEWTONLS SNESNEWTONTR SNESNGMRES SNESNGSFn SNESNRICHARDSON SNESObjectiveFn

SNESQN SNESSetFromOptions SNESSetFunction SNESSetJacobian SNESSetSolution SNESSolve SNESType SNESVINEWTONRSLS SNESVINEWTONSSLS SNESView SNES_CONERGED_ITERATING SNES_CONVERGED_FNORM_ABS SNES_CONVERGED_FNORM_RELATIVE SNES_CONVERGED_SNORM_RELATIVE SNES_DIVERGED_DTOL SNES_DIVERGED_FNORM_NAN SNES_DIVERGED_FUNCTION_COUNT SNES_DIVERGED_LINE_SEARCH SNES_DIVERGED_LOCAL_MIN SNES_DIVERGED_MAX_IT

Intermediate - Setting options for algorithms and data structures

DMSNESGetBoundaryLocal DMSetVI KSPMonitorSNESResidual KSPMonitorSNESResidualDrawLG KSPMonitorSNESResidualDrawLGCreate PetscConvEstGetConvRate PetscConvEstGetSolver PetscConvEstMonitorDefault PetscConvEstSetSolver SNESASPIN SNESCOMPOSITE SNESCompositeSetDamping SNESComputeJacobianDefault SNESComputeJacobianDefaultColor SNESConvergedReasonViewCancel SNESConvergedReasonViewSet SNESConvergenceTestFunction SNESGetApplicationContext SNESGetConvergedReason SNESGetConvergenceHistory SNESGetDM SNESGetDivergenceTolerance SNESGetErrorIfNotConverged SNESGetForceIteration SNESGetGridSequence SNESGetIterationNumber SNESGetLagJacobian SNESGetLagPreconditioner SNESGetLinearSolveFailures SNESGetLinearSolveIterations SNESGetMaxLinearSolveFailures SNESGetMaxNonlinearStepFailures SNESGetNPCSide SNESGetNonlinearStepFailures SNESGetNumberFunctionEvals SNESGetRhs SNESGetSolution SNESGetTolerances SNESGetType SNESGetUseMatrixFree SNESLineSearchApply SNESLineSearchBTGetAlpha SNESLineSearchBTSetAlpha SNESLineSearchComputeNorms SNESLineSearchGetDefaultMonitor SNESLineSearchGetOrder SNESLineSearchGetPostCheck SNESLineSearchGetPreCheck SNESLineSearchGetTolerances SNESLineSearchGetType

SNESLineSearchMonitorSet SNESLineSearchReason SNESLineSearchSetComputeNorms SNESLineSearchSetDamping SNESLineSearchSetDefaultMonitor SNESLineSearchSetFromOptions SNESLineSearchSetOrder SNESLineSearchSetPostCheck SNESLineSearchSetPreCheck SNESLineSearchSetTolerances SNESLineSearchSetType SNESLineSearchView SNESLoad SNESMSType SNESMonitorCancel SNESMonitorDefault SNESMonitorDefaultField SNESMonitorFields SNESMonitorJacUpdateSpectrum SNESMonitorRange SNESMonitorRatio SNESMonitorRatioSetUp SNESMonitorResidual SNESMonitorScaling SNESMonitorSet SNESMonitorSolution SNESMonitorSolutionUpdate SNESMultiblockSetBlockSize SNESMultiblockSetFields SNESMultiblockSetIS SNESNASMGetDamping SNESNASMGetNumber SNESNASMGetSNES SNESNASMGetSubdomains SNESNASMGetType SNESNASMSetDamping SNESNASMSetSubdomains SNESNASMSetType SNESNASMSetWeight SNESNCGSetType SNESNCGType SNESNEWTONTRDC SNESNGMRESRestartType SNESNGMRESSelectType SNESNGMRESSetRestartFmRise SNESNGMRESSetRestartType SNESNGMRESSetSelectType SNESNGSGetSweeps SNESNGSGetTolerances SNESNGSSetSweeps

SNESNGSSetTolerances SNESNewtonTRDCGetPostCheck SNESNewtonTRDCGetPreCheck SNESNewtonTRDCSetPostCheck SNESNewtonTRDCSetPreCheck SNESNewtonTRFallbackType SNESNewtonTRGetPostCheck SNESNewtonTRGetPreCheck SNESNewtonTRPostCheck SNESNewtonTRPreCheck SNESNewtonTRQNType SNESNewtonTRSetFallbackType SNESNewtonTRSetNormType SNESNewtonTRSetPostCheck SNESNewtonTRSetPreCheck SNESNewtonTRSetQNType SNESPATCH SNESPruneJacobianColor SNESPythonGetType SNESPythonSetType SNESQNRestartType SNESQNScaleType SNESQNSetRestartType SNESQNSetScaleType SNESQNSetType SNESQNType SNESReset SNESSetApplicationContext SNESSetComputeApplicationContext SNESSetComputeInitialGuess SNESSetConvergenceHistory SNESSetDM SNESSetDivergenceTolerance SNESSetErrorIfNotConverged SNESSetForceIteration SNESSetGridSequence SNESSetLagJacobian SNESSetLagPreconditioner SNESSetMaxLinearSolveFailures SNESSetMaxNonlinearStepFailures SNESSetNGS SNESSetNPCSide SNESSetObjective SNESSetPicard SNESSetTolerances SNESSetTrustRegionTolerance SNESSetType SNESSetUseMatrixFree SNESViewFromOptions

Advanced - Setting more advanced options and customization

DMSNESCreateJacobianMF DMSNESSetBoundaryLocal DMSNESSetFunctionLocal DMSNESSetJacobianLocal DMSNESSetObjectiveLocal MatCreateSNESMF MatCreateSNESMFMore MatSNESMFGetReuseBase MatSNESMFGetSNES MatSNESMFMoreSetParameters MatSNESMFSetReuseBase SNESAppendOptionsPrefix SNESConvergedCorrectPressure SNESConvergedReasonViewFromOptions SNESConvergedSkip SNESFunctionType SNESGetAlwaysComputesFinalResidual SNESGetCheckJacobianDomainError SNESGetFunction SNESGetFunctionType SNESGetJacobian SNESGetJacobianDomainError SNESGetNGS SNESGetNormSchedule SNESGetObjective SNESGetOptionsPrefix SNESGetPicard SNESGetSolutionUpdate SNESKSPGetParametersEW SNESKSPGetUseEW SNESKSPSetParametersEW SNESKSPSetUseEW SNESLINESEARCHBASIC

SNESLINESEARCHBT SNESLINESEARCHCP SNESLINESEARCHL2 SNESLINESEARCHNCGLINEAR SNESLINESEARCHNLEQERR SNESLINESEARCHSHELL SNESLineSearchAppendOptionsPrefix SNESLineSearchGetDamping SNESLineSearchGetLambda SNESLineSearchGetOptionsPrefix SNESLineSearchGetVIFunctions SNESLineSearchGetVecs SNESLineSearchMonitorCancel SNESLineSearchMonitorSetFromOptions SNESLineSearchPreCheck SNESLineSearchPreCheckPicard SNESLineSearchRegister SNESLineSearchRegisterAll SNESLineSearchSetLambda SNESLineSearchSetUp SNESLineSearchSetVIFunctions SNESLineSearchShellGetApply SNESLineSearchShellSetApply SNESLineSearchVIProjectFn SNESMS SNESMSGetDamping SNESMSGetType SNESMSRegister SNESMSSetDamping SNESMSSetType SNESMonitorFunction SNESMonitorSAWs SNESMonitorSetFromOptions

SNESMultiblockGetSubSNES SNESMultiblockSetType SNESNASM SNESNGS SNESNormSchedule SNESObjectiveComputeFunctionDefaultFD SNESRegister SNESRegisterAll SNESResetFromOptions SNESSHELL SNESSetAlwaysComputesFinalResidual SNESSetCheckJacobianDomainError SNESSetConvergenceTest SNESSetFunctionDomainError SNESSetJacobianDomainError SNESSetLagJacobianPersists SNESSetNormSchedule SNESSetOptionsPrefix SNESSetUp SNESSetUpdate SNESShellGetContext SNESShellSetContext SNESShellSetSolve SNESVIGetInactiveSet SNESVIGetVariableBounds SNESVISetComputeVariableBounds SNESVISetRedundancyCheck SNESVISetVariableBounds SNES_NORM_ALWAYS SNES_NORM_FINAL_ONLY SNES_NORM_INITIAL_FINAL_ONLY SNES_NORM_INITIAL_ONLY SNES_NORM_NONE

Developer - Interfaces rarely needed by applications programmers

DMCopyDMSNES DMGetDMSNES DMGetDMSNESWrite DMPlexSNESComputeBoundaryFEM DMPlexSNESComputeJacobianFEM DMPlexSNESComputeObjectiveFEM DMPlexSNESComputeResidualDS DMPlexSNESComputeResidualFEM DMPlexSetSNESLocalFEM DMSNES DMSNESCheckDiscretization DMSNESCheckFromOptions DMSNESCheckJacobian DMSNESCheckResidual DMSNESComputeJacobianAction DMSNESGetFunction DMSNESGetJacobian DMSNESGetNGS DMSNESGetObjective DMSNESGetPicard DMSNESSetFunction DMSNESSetFunctionContextDestroy DMSNESSetJacobian DMSNESSetJacobianContextDestroy DMSNESSetMFFunction DMSNESSetNGS DMSNESSetObjective DMSNESSetPicard MatMFFDComputeJacobian PetscConvEst PetscConvEstRateView SNESAddOptionsChecker

SNESApplyNPC SNESCompositeAddSNES SNESCompositeGetNumber SNESCompositeGetSNES SNESCompositeSetType SNESComputeFunction SNESComputeJacobian SNESComputeMFFunction SNESComputeNGS SNESComputeObjective SNESConverged SNESConvergedDefault SNESFinalizePackage SNESGetFunctionDomainError SNESGetFunctionNorm SNESGetNPC SNESGetNPCFunction SNESGetSolutionNorm SNESGetUpdateNorm SNESHasNPC SNESInitializePackage SNESLineSearchCreate SNESLineSearchDestroy SNESLineSearchGetNorms SNESLineSearchGetReason SNESLineSearchGetSNES SNESLineSearchMonitor SNESLineSearchMonitorSolutionUpdate SNESLineSearchPostCheck SNESLineSearchReset SNESLineSearchSetFunction SNESLineSearchSetNorms

SNESLineSearchSetReason SNESLineSearchSetSNES SNESLineSearchSetVecs SNESLineSearchSetWorkVecs SNESMSFinalizePackage SNESMSInitializePackage SNESMSRegisterAll SNESMSRegisterDestroy SNESMonitor SNESMonitorSAWsCreate SNESMonitorSAWsDestroy SNESNASMGetSubdomainVecs SNESNASMSetComputeFinalJacobian SNESNewtonTRDCGetRhoFlag SNESNewtonTRDCPostCheck SNESNewtonTRDCPreCheck SNESSetConvergedReason SNESSetCountersReset SNESSetFunctionNorm SNESSetFunctionType SNESSetInitialFunction SNESSetIterationNumber SNESSetKSP SNESSetLagPreconditionerPersists SNESSetLineSearch SNESSetNPC SNESSetUpMatrices SNESSetWorkVecs SNESVIComputeFunction SNESVIComputeMeritFunction SNESVIGetActiveSetIS

Single list of manual pages

DMCopyDMSNES DMDASNESSetFunctionLocal DMDASNESSetFunctionLocalVec DMDASNESSetJacobianLocal DMDASNESSetJacobianLocalVec DMDASNESSetObjectiveLocal DMDASNESSetObjectiveLocalVec DMDASNESSetPicardLocal DMGetDMSNES DMGetDMSNESWrite DMPlexSNESComputeBoundaryFEM DMPlexSNESComputeJacobianFEM DMPlexSNESComputeObjectiveFEM DMPlexSNESComputeResidualDS DMPlexSNESComputeResidualFEM DMPlexSetSNESLocalFEM DMSNES DMSNESCheckDiscretization DMSNESCheckFromOptions DMSNESCheckJacobian DMSNESCheckResidual DMSNESComputeJacobianAction DMSNESCreateJacobianMF DMSNESGetBoundaryLocal DMSNESGetFunction DMSNESGetFunctionLocal DMSNESGetJacobian DMSNESGetJacobianLocal DMSNESGetNGS DMSNESGetObjective DMSNESGetObjectiveLocal DMSNESGetPicard DMSNESSetBoundaryLocal DMSNESSetFunction DMSNESSetFunctionContextDestroy DMSNESSetFunctionLocal DMSNESSetJacobian DMSNESSetJacobianContextDestroy DMSNESSetJacobianLocal DMSNESSetMFFunction DMSNESSetNGS DMSNESSetObjective DMSNESSetObjectiveLocal DMSNESSetPicard DMSetVI KSPMonitorSNESResidual KSPMonitorSNESResidualDrawLG KSPMonitorSNESResidualDrawLGCreate MatCreateSNESMF MatCreateSNESMFMore MatMFFDComputeJacobian MatSNESMFGetReuseBase MatSNESMFGetSNES MatSNESMFMoreSetParameters MatSNESMFSetReuseBase PetscConvEst PetscConvEstCreate PetscConvEstDestroy PetscConvEstGetConvRate PetscConvEstGetSolver PetscConvEstMonitorDefault PetscConvEstRateView PetscConvEstSetFromOptions PetscConvEstSetSolver PetscConvEstSetUp PetscConvEstView SNES SNESANDERSON SNESASPIN SNESAddOptionsChecker SNESAppendOptionsPrefix SNESApplyNPC SNESCOMPOSITE SNESCompositeAddSNES SNESCompositeGetNumber SNESCompositeGetSNES SNESCompositeSetDamping SNESCompositeSetType SNESCompositeType SNESComputeFunction SNESComputeJacobian SNESComputeJacobianDefault SNESComputeJacobianDefaultColor SNESComputeMFFunction SNESComputeNGS SNESComputeObjective SNESConverged SNESConvergedCorrectPressure SNESConvergedDefault SNESConvergedReason SNESConvergedReasonView SNESConvergedReasonViewCancel SNESConvergedReasonViewFromOptions SNESConvergedReasonViewSet SNESConvergedSkip SNESConvergenceTestFunction SNESCreate SNESDestroy SNESFASType SNESFinalizePackage SNESFunctionFn SNESFunctionType SNESGetAlwaysComputesFinalResidual SNESGetApplicationContext SNESGetCheckJacobianDomainError SNESGetConvergedReason SNESGetConvergedReasonString SNESGetConvergenceHistory SNESGetDM SNESGetDivergenceTolerance SNESGetErrorIfNotConverged SNESGetForceIteration SNESGetFunction SNESGetFunctionDomainError SNESGetFunctionNorm SNESGetFunctionType SNESGetGridSequence SNESGetIterationNumber SNESGetJacobian SNESGetJacobianDomainError SNESGetKSP SNESGetLagJacobian SNESGetLagPreconditioner SNESGetLineSearch SNESGetLinearSolveFailures SNESGetLinearSolveIterations SNESGetMaxLinearSolveFailures SNESGetMaxNonlinearStepFailures SNESGetNGS SNESGetNPC SNESGetNPCFunction SNESGetNPCSide SNESGetNonlinearStepFailures SNESGetNormSchedule SNESGetNumberFunctionEvals

SNESGetObjective SNESGetOptionsPrefix SNESGetPicard SNESGetRhs SNESGetSolution SNESGetSolutionNorm SNESGetSolutionUpdate SNESGetTolerances SNESGetType SNESGetUpdateNorm SNESGetUseMatrixFree SNESHasNPC SNESInitialGuessFn SNESInitializePackage SNESJacobianFn SNESKSPGetParametersEW SNESKSPGetUseEW SNESKSPONLY SNESKSPSetParametersEW SNESKSPSetUseEW SNESKSPTRANSPOSEONLY SNESLINESEARCHBASIC SNESLINESEARCHBT SNESLINESEARCHCP SNESLINESEARCHL2 SNESLINESEARCHNCGLINEAR SNESLINESEARCHNLEQERR SNESLINESEARCHSHELL SNESLineSearch SNESLineSearchAppendOptionsPrefix SNESLineSearchApply SNESLineSearchBTGetAlpha SNESLineSearchBTSetAlpha SNESLineSearchComputeNorms SNESLineSearchCreate SNESLineSearchDestroy SNESLineSearchGetDamping SNESLineSearchGetDefaultMonitor SNESLineSearchGetLambda SNESLineSearchGetNorms SNESLineSearchGetOptionsPrefix SNESLineSearchGetOrder SNESLineSearchGetPostCheck SNESLineSearchGetPreCheck SNESLineSearchGetReason SNESLineSearchGetSNES SNESLineSearchGetTolerances SNESLineSearchGetType SNESLineSearchGetVIFunctions SNESLineSearchGetVecs SNESLineSearchMonitor SNESLineSearchMonitorCancel SNESLineSearchMonitorSet SNESLineSearchMonitorSetFromOptions SNESLineSearchMonitorSolutionUpdate SNESLineSearchPostCheck SNESLineSearchPreCheck SNESLineSearchPreCheckPicard SNESLineSearchReason SNESLineSearchRegister SNESLineSearchRegisterAll SNESLineSearchReset SNESLineSearchSetComputeNorms SNESLineSearchSetDamping SNESLineSearchSetDefaultMonitor SNESLineSearchSetFromOptions SNESLineSearchSetFunction SNESLineSearchSetLambda SNESLineSearchSetNorms SNESLineSearchSetOrder SNESLineSearchSetPostCheck SNESLineSearchSetPreCheck SNESLineSearchSetReason SNESLineSearchSetSNES SNESLineSearchSetTolerances SNESLineSearchSetType SNESLineSearchSetUp SNESLineSearchSetVIFunctions SNESLineSearchSetVecs SNESLineSearchSetWorkVecs SNESLineSearchShellGetApply SNESLineSearchShellSetApply SNESLineSearchType SNESLineSearchVIProjectFn SNESLineSearchView SNESLoad SNESMS SNESMSFinalizePackage SNESMSGetDamping SNESMSGetType SNESMSInitializePackage SNESMSRegister SNESMSRegisterAll SNESMSRegisterDestroy SNESMSSetDamping SNESMSSetType SNESMSType SNESMULTIBLOCK SNESMonitor SNESMonitorCancel SNESMonitorDefault SNESMonitorDefaultField SNESMonitorFields SNESMonitorFunction SNESMonitorJacUpdateSpectrum SNESMonitorRange SNESMonitorRatio SNESMonitorRatioSetUp SNESMonitorResidual SNESMonitorSAWs SNESMonitorSAWsCreate SNESMonitorSAWsDestroy SNESMonitorScaling SNESMonitorSet SNESMonitorSetFromOptions SNESMonitorSolution SNESMonitorSolutionUpdate SNESMultiblockGetSubSNES SNESMultiblockSetBlockSize SNESMultiblockSetFields SNESMultiblockSetIS SNESMultiblockSetType SNESNASM SNESNASMGetDamping SNESNASMGetNumber SNESNASMGetSNES SNESNASMGetSubdomainVecs SNESNASMGetSubdomains SNESNASMGetType SNESNASMSetComputeFinalJacobian SNESNASMSetDamping SNESNASMSetSubdomains SNESNASMSetType SNESNASMSetWeight SNESNCG

SNESNCGSetType SNESNCGType SNESNEWTONLS SNESNEWTONTR SNESNEWTONTRDC SNESNGMRES SNESNGMRESRestartType SNESNGMRESSelectType SNESNGMRESSetRestartFmRise SNESNGMRESSetRestartType SNESNGMRESSetSelectType SNESNGS SNESNGSFn SNESNGSGetSweeps SNESNGSGetTolerances SNESNGSSetSweeps SNESNGSSetTolerances SNESNRICHARDSON SNESNewtonTRDCGetPostCheck SNESNewtonTRDCGetPreCheck SNESNewtonTRDCGetRhoFlag SNESNewtonTRDCPostCheck SNESNewtonTRDCPreCheck SNESNewtonTRDCSetPostCheck SNESNewtonTRDCSetPreCheck SNESNewtonTRFallbackType SNESNewtonTRGetPostCheck SNESNewtonTRGetPreCheck SNESNewtonTRPostCheck SNESNewtonTRPreCheck SNESNewtonTRQNType SNESNewtonTRSetFallbackType SNESNewtonTRSetNormType SNESNewtonTRSetPostCheck SNESNewtonTRSetPreCheck SNESNewtonTRSetQNType SNESNormSchedule SNESObjectiveComputeFunctionDefaultFD SNESObjectiveFn SNESPATCH SNESPruneJacobianColor SNESPythonGetType SNESPythonSetType SNESQN SNESQNRestartType SNESQNScaleType SNESQNSetRestartType SNESQNSetScaleType SNESQNSetType SNESQNType SNESRegister SNESRegisterAll SNESReset SNESResetFromOptions SNESSHELL SNESSetAlwaysComputesFinalResidual SNESSetApplicationContext SNESSetCheckJacobianDomainError SNESSetComputeApplicationContext SNESSetComputeInitialGuess SNESSetConvergedReason SNESSetConvergenceHistory SNESSetConvergenceTest SNESSetCountersReset SNESSetDM SNESSetDivergenceTolerance SNESSetErrorIfNotConverged SNESSetForceIteration SNESSetFromOptions SNESSetFunction SNESSetFunctionDomainError SNESSetFunctionNorm SNESSetFunctionType SNESSetGridSequence SNESSetInitialFunction SNESSetIterationNumber SNESSetJacobian SNESSetJacobianDomainError SNESSetKSP SNESSetLagJacobian SNESSetLagJacobianPersists SNESSetLagPreconditioner SNESSetLagPreconditionerPersists SNESSetLineSearch SNESSetMaxLinearSolveFailures SNESSetMaxNonlinearStepFailures SNESSetNGS SNESSetNPC SNESSetNPCSide SNESSetNormSchedule SNESSetObjective SNESSetOptionsPrefix SNESSetPicard SNESSetSolution SNESSetTolerances SNESSetTrustRegionTolerance SNESSetType SNESSetUp SNESSetUpMatrices SNESSetUpdate SNESSetUseMatrixFree SNESSetWorkVecs SNESShellGetContext SNESShellSetContext SNESShellSetSolve SNESSolve SNESType SNESVIComputeFunction SNESVIComputeMeritFunction SNESVIGetActiveSetIS SNESVIGetInactiveSet SNESVIGetVariableBounds SNESVINEWTONRSLS SNESVINEWTONSSLS SNESVISetComputeVariableBounds SNESVISetRedundancyCheck SNESVISetVariableBounds SNESView SNESViewFromOptions SNES_CONERGED_ITERATING SNES_CONVERGED_FNORM_ABS SNES_CONVERGED_FNORM_RELATIVE SNES_CONVERGED_SNORM_RELATIVE SNES_DIVERGED_DTOL SNES_DIVERGED_FNORM_NAN SNES_DIVERGED_FUNCTION_COUNT SNES_DIVERGED_LINE_SEARCH SNES_DIVERGED_LOCAL_MIN SNES_DIVERGED_MAX_IT SNES_NORM_ALWAYS SNES_NORM_FINAL_ONLY SNES_NORM_INITIAL_FINAL_ONLY SNES_NORM_INITIAL_ONLY SNES_NORM_NONE