xref: /petsc/include/petscsnes.h (revision b24fb147d2f783efb2f58813f80260c02fe8ea96)
1 /*
2     User interface for the nonlinear solvers package.
3 */
4 #ifndef PETSCSNES_H
5 #define PETSCSNES_H
6 
7 #include <petscksp.h>
8 #include <petscdmtypes.h>
9 #include <petscfvtypes.h>
10 #include <petscdmdatypes.h>
11 
12 /* SUBMANSEC = SNES */
13 
14 /*S
15      SNES - Abstract PETSc object that manages nonlinear solves
16 
17    Level: beginner
18 
19 .seealso: [](doc_nonlinsolve), [](chapter_snes), `SNESCreate()`, `SNESSetType()`, `SNESType`, `TS`, `SNES`, `KSP`, `PC`, `SNESDestroy()`
20 S*/
21 typedef struct _p_SNES *SNES;
22 
23 /*J
24     SNESType - String with the name of a PETSc `SNES` method.
25 
26    Level: beginner
27 
28 .seealso: [](doc_nonlinsolve), [](chapter_snes), `SNESSetType()`, `SNES`, `SNESCreate()`, `SNESDestroy()`, `SNESSetFromOptions()`
29 J*/
30 typedef const char *SNESType;
31 #define SNESNEWTONLS         "newtonls"
32 #define SNESNEWTONTR         "newtontr"
33 #define SNESNEWTONTRDC       "newtontrdc"
34 #define SNESPYTHON           "python"
35 #define SNESNRICHARDSON      "nrichardson"
36 #define SNESKSPONLY          "ksponly"
37 #define SNESKSPTRANSPOSEONLY "ksptransposeonly"
38 #define SNESVINEWTONRSLS     "vinewtonrsls"
39 #define SNESVINEWTONSSLS     "vinewtonssls"
40 #define SNESNGMRES           "ngmres"
41 #define SNESQN               "qn"
42 #define SNESSHELL            "shell"
43 #define SNESNGS              "ngs"
44 #define SNESNCG              "ncg"
45 #define SNESFAS              "fas"
46 #define SNESMS               "ms"
47 #define SNESNASM             "nasm"
48 #define SNESANDERSON         "anderson"
49 #define SNESASPIN            "aspin"
50 #define SNESCOMPOSITE        "composite"
51 #define SNESPATCH            "patch"
52 
53 /* Logging support */
54 PETSC_EXTERN PetscClassId SNES_CLASSID;
55 PETSC_EXTERN PetscClassId DMSNES_CLASSID;
56 
57 PETSC_EXTERN PetscErrorCode SNESInitializePackage(void);
58 
59 PETSC_EXTERN PetscErrorCode SNESCreate(MPI_Comm, SNES *);
60 PETSC_EXTERN PetscErrorCode SNESReset(SNES);
61 PETSC_EXTERN PetscErrorCode SNESDestroy(SNES *);
62 PETSC_EXTERN PetscErrorCode SNESSetType(SNES, SNESType);
63 PETSC_EXTERN PetscErrorCode SNESMonitor(SNES, PetscInt, PetscReal);
64 PETSC_EXTERN PetscErrorCode SNESMonitorSet(SNES, PetscErrorCode (*)(SNES, PetscInt, PetscReal, void *), void *, PetscErrorCode (*)(void **));
65 PETSC_EXTERN PetscErrorCode SNESMonitorSetFromOptions(SNES, const char[], const char[], const char[], PetscErrorCode (*)(SNES, PetscInt, PetscReal, PetscViewerAndFormat *), PetscErrorCode (*)(SNES, PetscViewerAndFormat *));
66 PETSC_EXTERN PetscErrorCode SNESMonitorCancel(SNES);
67 PETSC_EXTERN PetscErrorCode SNESMonitorSAWs(SNES, PetscInt, PetscReal, void *);
68 PETSC_EXTERN PetscErrorCode SNESMonitorSAWsCreate(SNES, void **);
69 PETSC_EXTERN PetscErrorCode SNESMonitorSAWsDestroy(void **);
70 PETSC_EXTERN PetscErrorCode SNESSetConvergenceHistory(SNES, PetscReal[], PetscInt[], PetscInt, PetscBool);
71 PETSC_EXTERN PetscErrorCode SNESGetConvergenceHistory(SNES, PetscReal *[], PetscInt *[], PetscInt *);
72 PETSC_EXTERN PetscErrorCode SNESSetUp(SNES);
73 PETSC_EXTERN PetscErrorCode SNESSolve(SNES, Vec, Vec);
74 PETSC_EXTERN PetscErrorCode SNESSetErrorIfNotConverged(SNES, PetscBool);
75 PETSC_EXTERN PetscErrorCode SNESGetErrorIfNotConverged(SNES, PetscBool *);
76 
77 PETSC_EXTERN PetscErrorCode SNESSetWorkVecs(SNES, PetscInt);
78 
79 PETSC_EXTERN PetscErrorCode SNESAddOptionsChecker(PetscErrorCode (*)(SNES));
80 
81 PETSC_EXTERN PetscErrorCode SNESSetUpdate(SNES, PetscErrorCode (*)(SNES, PetscInt));
82 
83 PETSC_EXTERN PetscErrorCode SNESRegister(const char[], PetscErrorCode (*)(SNES));
84 
85 PETSC_EXTERN PetscErrorCode SNESGetKSP(SNES, KSP *);
86 PETSC_EXTERN PetscErrorCode SNESSetKSP(SNES, KSP);
87 PETSC_EXTERN PetscErrorCode SNESSetSolution(SNES, Vec);
88 PETSC_EXTERN PetscErrorCode SNESGetSolution(SNES, Vec *);
89 PETSC_EXTERN PetscErrorCode SNESGetSolutionUpdate(SNES, Vec *);
90 PETSC_EXTERN PetscErrorCode SNESGetRhs(SNES, Vec *);
91 PETSC_EXTERN PetscErrorCode SNESView(SNES, PetscViewer);
92 PETSC_EXTERN PetscErrorCode SNESLoad(SNES, PetscViewer);
93 PETSC_EXTERN PetscErrorCode SNESConvergedReasonViewSet(SNES, PetscErrorCode (*)(SNES, void *), void *, PetscErrorCode (*)(void **));
94 PETSC_EXTERN PetscErrorCode SNESViewFromOptions(SNES, PetscObject, const char[]);
95 PETSC_EXTERN PetscErrorCode SNESConvergedReasonView(SNES, PetscViewer);
96 PETSC_EXTERN PetscErrorCode SNESConvergedReasonViewFromOptions(SNES);
97 PETSC_EXTERN PetscErrorCode SNESConvergedReasonViewCancel(SNES);
98 
99 PETSC_DEPRECATED_FUNCTION("Use SNESConvergedReasonView() (since version 3.14)") static inline PetscErrorCode SNESReasonView(SNES snes, PetscViewer v)
100 {
101   return SNESConvergedReasonView(snes, v);
102 }
103 PETSC_DEPRECATED_FUNCTION("Use SNESConvergedReasonViewFromOptions() (since version 3.14)") static inline PetscErrorCode SNESReasonViewFromOptions(SNES snes)
104 {
105   return SNESConvergedReasonViewFromOptions(snes);
106 }
107 
108 #define SNES_FILE_CLASSID 1211224
109 
110 PETSC_EXTERN PetscErrorCode SNESSetOptionsPrefix(SNES, const char[]);
111 PETSC_EXTERN PetscErrorCode SNESAppendOptionsPrefix(SNES, const char[]);
112 PETSC_EXTERN PetscErrorCode SNESGetOptionsPrefix(SNES, const char *[]);
113 PETSC_EXTERN PetscErrorCode SNESSetFromOptions(SNES);
114 PETSC_EXTERN PetscErrorCode SNESResetFromOptions(SNES);
115 
116 PETSC_EXTERN PetscErrorCode SNESSetUseMatrixFree(SNES, PetscBool, PetscBool);
117 PETSC_EXTERN PetscErrorCode SNESGetUseMatrixFree(SNES, PetscBool *, PetscBool *);
118 PETSC_EXTERN PetscErrorCode MatCreateSNESMF(SNES, Mat *);
119 PETSC_EXTERN PetscErrorCode MatSNESMFGetSNES(Mat, SNES *);
120 PETSC_EXTERN PetscErrorCode MatSNESMFSetReuseBase(Mat, PetscBool);
121 PETSC_EXTERN PetscErrorCode MatSNESMFGetReuseBase(Mat, PetscBool *);
122 PETSC_EXTERN PetscErrorCode MatMFFDComputeJacobian(SNES, Vec, Mat, Mat, void *);
123 PETSC_EXTERN PetscErrorCode MatCreateSNESMFMore(SNES, Vec, Mat *);
124 PETSC_EXTERN PetscErrorCode MatSNESMFMoreSetParameters(Mat, PetscReal, PetscReal, PetscReal);
125 
126 PETSC_EXTERN PetscErrorCode SNESGetType(SNES, SNESType *);
127 PETSC_EXTERN PetscErrorCode SNESMonitorDefaultSetUp(SNES, PetscViewerAndFormat *);
128 PETSC_EXTERN PetscErrorCode SNESMonitorDefault(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
129 PETSC_EXTERN PetscErrorCode SNESMonitorScaling(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
130 PETSC_EXTERN PetscErrorCode SNESMonitorRange(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
131 PETSC_EXTERN PetscErrorCode SNESMonitorRatio(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
132 PETSC_EXTERN PetscErrorCode SNESMonitorRatioSetUp(SNES, PetscViewerAndFormat *);
133 PETSC_EXTERN PetscErrorCode SNESMonitorSolution(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
134 PETSC_EXTERN PetscErrorCode SNESMonitorResidual(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
135 PETSC_EXTERN PetscErrorCode SNESMonitorSolutionUpdate(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
136 PETSC_EXTERN PetscErrorCode SNESMonitorDefaultShort(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
137 PETSC_EXTERN PetscErrorCode SNESMonitorDefaultField(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
138 PETSC_EXTERN PetscErrorCode SNESMonitorJacUpdateSpectrum(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
139 PETSC_EXTERN PetscErrorCode SNESMonitorFields(SNES, PetscInt, PetscReal, PetscViewerAndFormat *);
140 PETSC_EXTERN PetscErrorCode KSPMonitorSNESResidual(KSP, PetscInt, PetscReal, PetscViewerAndFormat *);
141 PETSC_EXTERN PetscErrorCode KSPMonitorSNESResidualDrawLG(KSP, PetscInt, PetscReal, PetscViewerAndFormat *);
142 PETSC_EXTERN PetscErrorCode KSPMonitorSNESResidualDrawLGCreate(PetscViewer, PetscViewerFormat, void *, PetscViewerAndFormat **);
143 
144 PETSC_EXTERN PetscErrorCode SNESSetTolerances(SNES, PetscReal, PetscReal, PetscReal, PetscInt, PetscInt);
145 PETSC_EXTERN PetscErrorCode SNESSetDivergenceTolerance(SNES, PetscReal);
146 PETSC_EXTERN PetscErrorCode SNESGetTolerances(SNES, PetscReal *, PetscReal *, PetscReal *, PetscInt *, PetscInt *);
147 PETSC_EXTERN PetscErrorCode SNESGetDivergenceTolerance(SNES, PetscReal *);
148 PETSC_EXTERN PetscErrorCode SNESSetTrustRegionTolerance(SNES, PetscReal);
149 PETSC_EXTERN PetscErrorCode SNESGetForceIteration(SNES, PetscBool *);
150 PETSC_EXTERN PetscErrorCode SNESSetForceIteration(SNES, PetscBool);
151 PETSC_EXTERN PetscErrorCode SNESGetIterationNumber(SNES, PetscInt *);
152 PETSC_EXTERN PetscErrorCode SNESSetIterationNumber(SNES, PetscInt);
153 
154 /*E
155     SNESNewtonTRFallbackType - type of fallback in case the solution of the trust-region subproblem is outside of the radius
156 
157    Values:
158 +  `SNES_TR_FALLBACK_NEWTON` - use scaled Newton step
159 .  `SNES_TR_FALLBACK_CAUCHY` - use Cauchy direction
160 -  `SNES_TR_FALLBACK_DOGLEG` - use dogleg method
161 
162    Level: intermediate
163 
164 .seealso: [](chapter_snes), `SNES`, `SNESNEWTONTR`, `SNESNEWTONTRDC`
165 E*/
166 typedef enum {
167   SNES_TR_FALLBACK_NEWTON,
168   SNES_TR_FALLBACK_CAUCHY,
169   SNES_TR_FALLBACK_DOGLEG,
170 } SNESNewtonTRFallbackType;
171 
172 PETSC_EXTERN const char *const SNESNewtonTRFallbackTypes[];
173 
174 PETSC_EXTERN PetscErrorCode SNESNewtonTRSetPreCheck(SNES, PetscErrorCode (*)(SNES, Vec, Vec, PetscBool *, void *), void *ctx);
175 PETSC_EXTERN PetscErrorCode SNESNewtonTRGetPreCheck(SNES, PetscErrorCode (**)(SNES, Vec, Vec, PetscBool *, void *), void **ctx);
176 PETSC_EXTERN PetscErrorCode SNESNewtonTRSetPostCheck(SNES, PetscErrorCode (*)(SNES, Vec, Vec, Vec, PetscBool *, PetscBool *, void *), void *ctx);
177 PETSC_EXTERN PetscErrorCode SNESNewtonTRGetPostCheck(SNES, PetscErrorCode (**)(SNES, Vec, Vec, Vec, PetscBool *, PetscBool *, void *), void **ctx);
178 PETSC_EXTERN PetscErrorCode SNESNewtonTRSetFallbackType(SNES, SNESNewtonTRFallbackType);
179 PETSC_EXTERN PetscErrorCode SNESNewtonTRPreCheck(SNES, Vec, Vec, PetscBool *);
180 PETSC_EXTERN PetscErrorCode SNESNewtonTRPostCheck(SNES, Vec, Vec, Vec, PetscBool *, PetscBool *);
181 
182 /* TRDC API, to be removed after 3.19 */
183 PETSC_EXTERN PetscErrorCode SNESNewtonTRDCGetRhoFlag(SNES, PetscBool *);
184 PETSC_EXTERN PetscErrorCode SNESNewtonTRDCSetPreCheck(SNES, PetscErrorCode (*)(SNES, Vec, Vec, PetscBool *, void *), void *ctx);
185 PETSC_EXTERN PetscErrorCode SNESNewtonTRDCGetPreCheck(SNES, PetscErrorCode (**)(SNES, Vec, Vec, PetscBool *, void *), void **ctx);
186 PETSC_EXTERN PetscErrorCode SNESNewtonTRDCSetPostCheck(SNES, PetscErrorCode (*)(SNES, Vec, Vec, Vec, PetscBool *, PetscBool *, void *), void *ctx);
187 PETSC_EXTERN PetscErrorCode SNESNewtonTRDCGetPostCheck(SNES, PetscErrorCode (**)(SNES, Vec, Vec, Vec, PetscBool *, PetscBool *, void *), void **ctx);
188 
189 PETSC_EXTERN PetscErrorCode SNESGetNonlinearStepFailures(SNES, PetscInt *);
190 PETSC_EXTERN PetscErrorCode SNESSetMaxNonlinearStepFailures(SNES, PetscInt);
191 PETSC_EXTERN PetscErrorCode SNESGetMaxNonlinearStepFailures(SNES, PetscInt *);
192 PETSC_EXTERN PetscErrorCode SNESGetNumberFunctionEvals(SNES, PetscInt *);
193 
194 PETSC_EXTERN PetscErrorCode SNESSetLagPreconditioner(SNES, PetscInt);
195 PETSC_EXTERN PetscErrorCode SNESGetLagPreconditioner(SNES, PetscInt *);
196 PETSC_EXTERN PetscErrorCode SNESSetLagJacobian(SNES, PetscInt);
197 PETSC_EXTERN PetscErrorCode SNESGetLagJacobian(SNES, PetscInt *);
198 PETSC_EXTERN PetscErrorCode SNESSetLagPreconditionerPersists(SNES, PetscBool);
199 PETSC_EXTERN PetscErrorCode SNESSetLagJacobianPersists(SNES, PetscBool);
200 PETSC_EXTERN PetscErrorCode SNESSetGridSequence(SNES, PetscInt);
201 PETSC_EXTERN PetscErrorCode SNESGetGridSequence(SNES, PetscInt *);
202 
203 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveIterations(SNES, PetscInt *);
204 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveFailures(SNES, PetscInt *);
205 PETSC_EXTERN PetscErrorCode SNESSetMaxLinearSolveFailures(SNES, PetscInt);
206 PETSC_EXTERN PetscErrorCode SNESGetMaxLinearSolveFailures(SNES, PetscInt *);
207 PETSC_EXTERN PetscErrorCode SNESSetCountersReset(SNES, PetscBool);
208 
209 PETSC_EXTERN PetscErrorCode SNESKSPSetUseEW(SNES, PetscBool);
210 PETSC_EXTERN PetscErrorCode SNESKSPGetUseEW(SNES, PetscBool *);
211 PETSC_EXTERN PetscErrorCode SNESKSPSetParametersEW(SNES, PetscInt, PetscReal, PetscReal, PetscReal, PetscReal, PetscReal, PetscReal);
212 PETSC_EXTERN PetscErrorCode SNESKSPGetParametersEW(SNES, PetscInt *, PetscReal *, PetscReal *, PetscReal *, PetscReal *, PetscReal *, PetscReal *);
213 
214 #include <petscdrawtypes.h>
215 PETSC_EXTERN PetscErrorCode SNESMonitorLGRange(SNES, PetscInt, PetscReal, void *);
216 
217 PETSC_EXTERN PetscErrorCode SNESSetApplicationContext(SNES, void *);
218 PETSC_EXTERN PetscErrorCode SNESGetApplicationContext(SNES, void *);
219 PETSC_EXTERN PetscErrorCode SNESSetComputeApplicationContext(SNES, PetscErrorCode (*)(SNES, void **), PetscErrorCode (*)(void **));
220 
221 PETSC_EXTERN PetscErrorCode SNESPythonSetType(SNES, const char[]);
222 PETSC_EXTERN PetscErrorCode SNESPythonGetType(SNES, const char *[]);
223 
224 PETSC_EXTERN PetscErrorCode SNESSetFunctionDomainError(SNES);
225 PETSC_EXTERN PetscErrorCode SNESGetFunctionDomainError(SNES, PetscBool *);
226 PETSC_EXTERN PetscErrorCode SNESGetJacobianDomainError(SNES, PetscBool *);
227 PETSC_EXTERN PetscErrorCode SNESSetJacobianDomainError(SNES);
228 PETSC_EXTERN PetscErrorCode SNESSetCheckJacobianDomainError(SNES, PetscBool);
229 PETSC_EXTERN PetscErrorCode SNESGetCheckJacobianDomainError(SNES, PetscBool *);
230 
231 #define SNES_CONVERGED_TR_DELTA_DEPRECATED SNES_CONVERGED_TR_DELTA PETSC_DEPRECATED_ENUM("Use SNES_DIVERGED_TR_DELTA (since version 3.12)")
232 /*E
233     SNESConvergedReason - reason a `SNESSolve()` was determined to have converged or diverged
234 
235    Values:
236 +  `SNES_CONVERGED_FNORM_ABS` - 2-norm(F) <= abstol
237 .  `SNES_CONVERGED_FNORM_RELATIVE` - 2-norm(F) <= rtol*2-norm(F(x_0)) where x_0 is the initial guess
238 .  `SNES_CONVERGED_SNORM_RELATIVE` - The 2-norm of the last step <= stol * 2-norm(x) where x is the current
239 .  `SNES_DIVERGED_FUNCTION_COUNT` - The user provided function has been called more times than the maximum set in `SNESSetTolerances()`
240 .  `SNES_DIVERGED_DTOL` - The norm of the function has increased by a factor of divtol set with `SNESSetDivergenceTolerance()`
241 .  `SNES_DIVERGED_FNORM_NAN` - the 2-norm of the current function evaluation is not-a-number (NaN), this
242       is usually caused by a division of 0 by 0.
243 .  `SNES_DIVERGED_MAX_IT` - `SNESSolve()` has reached the maximum number of iterations requested
244 .  `SNES_DIVERGED_LINE_SEARCH` - The line search has failed. This only occurs for `SNES` solvers that use a line search
245 .  `SNES_DIVERGED_LOCAL_MIN` - the algorithm seems to have stagnated at a local minimum that is not zero.
246 -  `SNES_CONERGED_ITERATING` - this only occurs if `SNESGetConvergedReason()` is called during the `SNESSolve()`
247 
248    Level: beginner
249 
250     Notes:
251    The two most common reasons for divergence are an incorrectly coded or computed Jacobian or failure or lack of convergence in the linear system (in this case we recommend
252    testing with `-pc_type lu` to eliminate the linear solver as the cause of the problem).
253 
254    `SNES_DIVERGED_LOCAL_MIN` can only occur when using the line-search variant of `SNES`.
255        The line search wants to minimize Q(alpha) = 1/2 || F(x + alpha s) ||^2_2  this occurs
256        at Q'(alpha) = s^T F'(x+alpha s)^T F(x+alpha s) = 0. If s is the Newton direction - F'(x)^(-1)F(x) then
257        you get Q'(alpha) = -F(x)^T F'(x)^(-1)^T F'(x+alpha s)F(x+alpha s); when alpha = 0
258        Q'(0) = - ||F(x)||^2_2 which is always NEGATIVE if F'(x) is invertible. This means the Newton
259        direction is a descent direction and the line search should succeed if alpha is small enough.
260 
261        If F'(x) is NOT invertible AND F'(x)^T F(x) = 0 then Q'(0) = 0 and the Newton direction
262        is NOT a descent direction so the line search will fail. All one can do at this point
263        is change the initial guess and try again.
264 
265        An alternative explanation: Newton's method can be regarded as replacing the function with
266        its linear approximation and minimizing the 2-norm of that. That is F(x+s) approx F(x) + F'(x)s
267        so we minimize || F(x) + F'(x) s ||^2_2; do this using Least Squares. If F'(x) is invertible then
268        s = - F'(x)^(-1)F(x) otherwise F'(x)^T F'(x) s = -F'(x)^T F(x). If F'(x)^T F(x) is NOT zero then there
269        exists a nontrivial (that is F'(x)s != 0) solution to the equation and this direction is
270        s = - [F'(x)^T F'(x)]^(-1) F'(x)^T F(x) so Q'(0) = - F(x)^T F'(x) [F'(x)^T F'(x)]^(-T) F'(x)^T F(x)
271        = - (F'(x)^T F(x)) [F'(x)^T F'(x)]^(-T) (F'(x)^T F(x)). Since we are assuming (F'(x)^T F(x)) != 0
272        and F'(x)^T F'(x) has no negative eigenvalues Q'(0) < 0 so s is a descent direction and the line
273        search should succeed for small enough alpha.
274 
275        Note that this RARELY happens in practice. Far more likely the linear system is not being solved
276        (well enough?) or the Jacobian is wrong.
277 
278    `SNES_DIVERGED_MAX_IT` means that the solver reached the maximum number of iterations without satisfying any
279    convergence criteria. `SNES_CONVERGED_ITS` means that `SNESConvergedSkip()` was chosen as the convergence test;
280    thus the usual convergence criteria have not been checked and may or may not be satisfied.
281 
282 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `KSPConvergedReason`, `SNESSetConvergenceTest()`, `SNESSetTolerances()`
283 E*/
284 typedef enum {                       /* converged */
285   SNES_CONVERGED_FNORM_ABS      = 2, /* ||F|| < atol */
286   SNES_CONVERGED_FNORM_RELATIVE = 3, /* ||F|| < rtol*||F_initial|| */
287   SNES_CONVERGED_SNORM_RELATIVE = 4, /* Newton computed step size small; || delta x || < stol || x ||*/
288   SNES_CONVERGED_ITS            = 5, /* maximum iterations reached */
289   SNES_BREAKOUT_INNER_ITER      = 6, /* Flag to break out of inner loop after checking custom convergence. */
290                                      /* it is used in multi-phase flow when state changes */
291   /* diverged */
292   SNES_DIVERGED_FUNCTION_DOMAIN      = -1, /* the new x location passed the function is not in the domain of F */
293   SNES_DIVERGED_FUNCTION_COUNT       = -2,
294   SNES_DIVERGED_LINEAR_SOLVE         = -3, /* the linear solve failed */
295   SNES_DIVERGED_FNORM_NAN            = -4,
296   SNES_DIVERGED_MAX_IT               = -5,
297   SNES_DIVERGED_LINE_SEARCH          = -6,  /* the line search failed */
298   SNES_DIVERGED_INNER                = -7,  /* inner solve failed */
299   SNES_DIVERGED_LOCAL_MIN            = -8,  /* || J^T b || is small, implies converged to local minimum of F() */
300   SNES_DIVERGED_DTOL                 = -9,  /* || F || > divtol*||F_initial|| */
301   SNES_DIVERGED_JACOBIAN_DOMAIN      = -10, /* Jacobian calculation does not make sense */
302   SNES_DIVERGED_TR_DELTA             = -11,
303   SNES_CONVERGED_TR_DELTA_DEPRECATED = -11,
304 
305   SNES_CONVERGED_ITERATING = 0
306 } SNESConvergedReason;
307 PETSC_EXTERN const char *const *SNESConvergedReasons;
308 
309 /*MC
310      SNES_CONVERGED_FNORM_ABS - 2-norm(F) <= abstol
311 
312    Level: beginner
313 
314 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`
315 M*/
316 
317 /*MC
318      SNES_CONVERGED_FNORM_RELATIVE - 2-norm(F) <= rtol*2-norm(F(x_0)) where x_0 is the initial guess
319 
320    Level: beginner
321 
322 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`
323 M*/
324 
325 /*MC
326      SNES_CONVERGED_SNORM_RELATIVE - The 2-norm of the last step <= stol * 2-norm(x) where x is the current
327           solution and stol is the 4th argument to `SNESSetTolerances()`
328 
329      Options Database Keys:
330       -snes_stol <stol> - the step tolerance
331 
332    Level: beginner
333 
334 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`
335 M*/
336 
337 /*MC
338      SNES_DIVERGED_FUNCTION_COUNT - The user provided function has been called more times then the final
339          argument to `SNESSetTolerances()`
340 
341    Level: beginner
342 
343 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`
344 M*/
345 
346 /*MC
347      SNES_DIVERGED_DTOL - The norm of the function has increased by a factor of divtol set with `SNESSetDivergenceTolerance()`
348 
349    Level: beginner
350 
351 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`, `SNESSetDivergenceTolerance()`
352 M*/
353 
354 /*MC
355      SNES_DIVERGED_FNORM_NAN - the 2-norm of the current function evaluation is not-a-number (NaN), this
356       is usually caused by a division of 0 by 0.
357 
358    Level: beginner
359 
360 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`
361 M*/
362 
363 /*MC
364      SNES_DIVERGED_MAX_IT - SNESSolve() has reached the maximum number of iterations requested
365 
366    Level: beginner
367 
368 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`
369 M*/
370 
371 /*MC
372      SNES_DIVERGED_LINE_SEARCH - The line search has failed. This only occurs for a `SNES` solvers that use a line search
373 
374    Level: beginner
375 
376 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`, `SNESLineSearch`
377 M*/
378 
379 /*MC
380      SNES_DIVERGED_LOCAL_MIN - the algorithm seems to have stagnated at a local minimum that is not zero.
381         See the manual page for `SNESConvergedReason` for more details
382 
383    Level: beginner
384 
385 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`
386 M*/
387 
388 /*MC
389      SNES_CONERGED_ITERATING - this only occurs if `SNESGetConvergedReason()` is called during the `SNESSolve()`
390 
391    Level: beginner
392 
393 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `SNESConvergedReason`, `SNESSetTolerances()`
394 M*/
395 
396 PETSC_EXTERN PetscErrorCode SNESSetConvergenceTest(SNES, PetscErrorCode (*)(SNES, PetscInt, PetscReal, PetscReal, PetscReal, SNESConvergedReason *, void *), void *, PetscErrorCode (*)(void *));
397 PETSC_EXTERN PetscErrorCode SNESConvergedDefault(SNES, PetscInt, PetscReal, PetscReal, PetscReal, SNESConvergedReason *, void *);
398 PETSC_EXTERN PetscErrorCode SNESConvergedSkip(SNES, PetscInt, PetscReal, PetscReal, PetscReal, SNESConvergedReason *, void *);
399 PETSC_EXTERN PetscErrorCode SNESConvergedCorrectPressure(SNES, PetscInt, PetscReal, PetscReal, PetscReal, SNESConvergedReason *, void *);
400 PETSC_EXTERN PetscErrorCode SNESGetConvergedReason(SNES, SNESConvergedReason *);
401 PETSC_EXTERN PetscErrorCode SNESGetConvergedReasonString(SNES, const char **);
402 PETSC_EXTERN PetscErrorCode SNESSetConvergedReason(SNES, SNESConvergedReason);
403 
404 PETSC_DEPRECATED_FUNCTION("Use SNESConvergedSkip() (since version 3.5)") static inline void SNESSkipConverged(void)
405 { /* never called */
406 }
407 #define SNESSkipConverged (SNESSkipConverged, SNESConvergedSkip)
408 
409 /* --------- Solving systems of nonlinear equations --------------- */
410 PETSC_EXTERN PetscErrorCode SNESSetFunction(SNES, Vec, PetscErrorCode (*)(SNES, Vec, Vec, void *), void *);
411 PETSC_EXTERN PetscErrorCode SNESGetFunction(SNES, Vec *, PetscErrorCode (**)(SNES, Vec, Vec, void *), void **);
412 PETSC_EXTERN PetscErrorCode SNESComputeFunction(SNES, Vec, Vec);
413 PETSC_EXTERN PetscErrorCode SNESComputeMFFunction(SNES, Vec, Vec);
414 PETSC_EXTERN PetscErrorCode SNESSetInitialFunction(SNES, Vec);
415 
416 PETSC_EXTERN PetscErrorCode SNESSetJacobian(SNES, Mat, Mat, PetscErrorCode (*)(SNES, Vec, Mat, Mat, void *), void *);
417 PETSC_EXTERN PetscErrorCode SNESGetJacobian(SNES, Mat *, Mat *, PetscErrorCode (**)(SNES, Vec, Mat, Mat, void *), void **);
418 PETSC_EXTERN PetscErrorCode SNESObjectiveComputeFunctionDefaultFD(SNES, Vec, Vec, void *);
419 PETSC_EXTERN PetscErrorCode SNESComputeJacobianDefault(SNES, Vec, Mat, Mat, void *);
420 PETSC_EXTERN PetscErrorCode SNESComputeJacobianDefaultColor(SNES, Vec, Mat, Mat, void *);
421 PETSC_EXTERN PetscErrorCode SNESPruneJacobianColor(SNES, Mat, Mat);
422 PETSC_EXTERN PetscErrorCode SNESSetComputeInitialGuess(SNES, PetscErrorCode (*)(SNES, Vec, void *), void *);
423 PETSC_EXTERN PetscErrorCode SNESSetPicard(SNES, Vec, PetscErrorCode (*)(SNES, Vec, Vec, void *), Mat, Mat, PetscErrorCode (*)(SNES, Vec, Mat, Mat, void *), void *);
424 PETSC_EXTERN PetscErrorCode SNESGetPicard(SNES, Vec *, PetscErrorCode (**)(SNES, Vec, Vec, void *), Mat *, Mat *, PetscErrorCode (**)(SNES, Vec, Mat, Mat, void *), void **);
425 PETSC_EXTERN PetscErrorCode SNESPicardComputeFunction(SNES, Vec, Vec, void *);
426 PETSC_EXTERN PetscErrorCode SNESPicardComputeMFFunction(SNES, Vec, Vec, void *);
427 PETSC_EXTERN PetscErrorCode SNESPicardComputeJacobian(SNES, Vec, Mat, Mat, void *);
428 
429 PETSC_EXTERN PetscErrorCode SNESSetObjective(SNES, PetscErrorCode (*)(SNES, Vec, PetscReal *, void *), void *);
430 PETSC_EXTERN PetscErrorCode SNESGetObjective(SNES, PetscErrorCode (**)(SNES, Vec, PetscReal *, void *), void **);
431 PETSC_EXTERN PetscErrorCode SNESComputeObjective(SNES, Vec, PetscReal *);
432 
433 /*E
434     SNESNormSchedule - Frequency with which the norm is computed during a nonliner solve
435 
436    Values:
437 +   `SNES_NORM_DEFAULT` - use the default behavior for the current `SNESType`
438 .   `SNES_NORM_NONE` - avoid all norm computations
439 .   `SNES_NORM_ALWAYS` - compute the norms whenever possible
440 .   `SNES_NORM_INITIAL_ONLY` - compute the norm only when the algorithm starts
441 .   `SNES_NORM_FINAL_ONLY` - compute the norm only when the algorithm finishes
442 -   `SNES_NORM_INITIAL_FINAL_ONLY` - compute the norm at the start and end of the algorithm
443 
444    Level: advanced
445 
446    Notes:
447    Support for these is highly dependent on the solver.
448 
449    Some options limit the convergence tests that can be used.
450 
451    The `SNES_NORM_NONE` option is most commonly used when the nonlinear solver is being used as a smoother, for example for `SNESFAS`
452 
453    This is primarily used to turn off extra norm and function computation
454    when the solvers are composed.
455 
456 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `KSPSetNormType()`,
457           `KSPSetConvergenceTest()`, `KSPSetPCSide()`
458 E*/
459 typedef enum {
460   SNES_NORM_DEFAULT            = -1,
461   SNES_NORM_NONE               = 0,
462   SNES_NORM_ALWAYS             = 1,
463   SNES_NORM_INITIAL_ONLY       = 2,
464   SNES_NORM_FINAL_ONLY         = 3,
465   SNES_NORM_INITIAL_FINAL_ONLY = 4
466 } SNESNormSchedule;
467 PETSC_EXTERN const char *const *const SNESNormSchedules;
468 
469 /*MC
470     SNES_NORM_NONE - Don't compute function and its L2 norm when possible
471 
472    Level: advanced
473 
474     Note:
475     This is most useful for stationary solvers with a fixed number of iterations used as smoothers.
476 
477 .seealso: [](chapter_snes), `SNESNormSchedule`, `SNES`, `SNESSetNormSchedule()`, `SNES_NORM_DEFAULT`
478 M*/
479 
480 /*MC
481     SNES_NORM_ALWAYS - Compute the function and its L2 norm at each iteration.
482 
483    Level: advanced
484 
485     Note:
486     Most solvers will use this no matter what norm type is passed to them.
487 
488 .seealso: [](chapter_snes), `SNESNormSchedule`, `SNES`, `SNESSetNormSchedule()`, `SNES_NORM_NONE`
489 M*/
490 
491 /*MC
492     SNES_NORM_INITIAL_ONLY - Compute the function and its L2 at iteration 0, but do not update it.
493 
494    Level: advanced
495 
496    Notes:
497    This method is useful in composed methods, when a true solution might actually be found before `SNESSolve()` is called.
498    This option enables the solve to abort on the zeroth iteration if this is the case.
499 
500    For solvers that require the computation of the L2 norm of the function as part of the method, this merely cancels
501    the norm computation at the last iteration (if possible).
502 
503 .seealso: [](chapter_snes), `SNESNormSchedule`, `SNES`, `SNESSetNormSchedule()`, `SNES_NORM_FINAL_ONLY`, `SNES_NORM_INITIAL_FINAL_ONLY`
504 M*/
505 
506 /*MC
507     SNES_NORM_FINAL_ONLY - Compute the function and its L2 norm on only the final iteration.
508 
509    Level: advanced
510 
511    Note:
512    For solvers that require the computation of the L2 norm of the function as part of the method, behaves
513    exactly as `SNES_NORM_DEFAULT`.  This method is useful when the function is gotten after `SNESSolve()` and
514    used in subsequent computation for methods that do not need the norm computed during the rest of the
515    solution procedure.
516 
517 .seealso: [](chapter_snes), `SNESNormSchedule`, `SNES`, `SNESSetNormSchedule()`, `SNES_NORM_INITIAL_ONLY`, `SNES_NORM_INITIAL_FINAL_ONLY`
518 M*/
519 
520 /*MC
521     SNES_NORM_INITIAL_FINAL_ONLY - Compute the function and its L2 norm on only the initial and final iterations.
522 
523    Level: advanced
524 
525    Note:
526    This method combines the benefits of `SNES_NORM_INITIAL_ONLY` and `SNES_NORM_FINAL_ONLY`.
527 
528 .seealso: [](chapter_snes), `SNESNormSchedule`, `SNES`, `SNESSetNormSchedule()`, `SNES_NORM_SNES_NORM_INITIAL_ONLY`, `SNES_NORM_FINAL_ONLY`
529 M*/
530 
531 PETSC_EXTERN PetscErrorCode SNESSetNormSchedule(SNES, SNESNormSchedule);
532 PETSC_EXTERN PetscErrorCode SNESGetNormSchedule(SNES, SNESNormSchedule *);
533 PETSC_EXTERN PetscErrorCode SNESSetFunctionNorm(SNES, PetscReal);
534 PETSC_EXTERN PetscErrorCode SNESGetFunctionNorm(SNES, PetscReal *);
535 PETSC_EXTERN PetscErrorCode SNESGetUpdateNorm(SNES, PetscReal *);
536 PETSC_EXTERN PetscErrorCode SNESGetSolutionNorm(SNES, PetscReal *);
537 
538 /*E
539     SNESFunctionType - Type of function computed
540 
541    Values:
542 +  `SNES_FUNCTION_DEFAULT` - the default behavior for the current `SNESType`
543 .  `SNES_FUNCTION_UNPRECONDITIONED` - the original function provided
544 -  `SNES_FUNCTION_PRECONDITIONED` - the modification of the function by the preconditioner
545 
546    Level: advanced
547 
548    Note:
549    Support for these is dependent on the solver.
550 
551 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `KSPSetNormType()`,
552           `KSPSetConvergenceTest()`, `KSPSetPCSide()`
553 E*/
554 typedef enum {
555   SNES_FUNCTION_DEFAULT          = -1,
556   SNES_FUNCTION_UNPRECONDITIONED = 0,
557   SNES_FUNCTION_PRECONDITIONED   = 1
558 } SNESFunctionType;
559 PETSC_EXTERN const char *const *const SNESFunctionTypes;
560 
561 PETSC_EXTERN PetscErrorCode SNESSetFunctionType(SNES, SNESFunctionType);
562 PETSC_EXTERN PetscErrorCode SNESGetFunctionType(SNES, SNESFunctionType *);
563 
564 PETSC_EXTERN PetscErrorCode SNESSetNGS(SNES, PetscErrorCode (*)(SNES, Vec, Vec, void *), void *);
565 PETSC_EXTERN PetscErrorCode SNESGetNGS(SNES, PetscErrorCode (**)(SNES, Vec, Vec, void *), void **);
566 PETSC_EXTERN PetscErrorCode SNESComputeNGS(SNES, Vec, Vec);
567 
568 PETSC_EXTERN PetscErrorCode SNESNGSSetSweeps(SNES, PetscInt);
569 PETSC_EXTERN PetscErrorCode SNESNGSGetSweeps(SNES, PetscInt *);
570 PETSC_EXTERN PetscErrorCode SNESNGSSetTolerances(SNES, PetscReal, PetscReal, PetscReal, PetscInt);
571 PETSC_EXTERN PetscErrorCode SNESNGSGetTolerances(SNES, PetscReal *, PetscReal *, PetscReal *, PetscInt *);
572 
573 PETSC_EXTERN PetscErrorCode SNESSetAlwaysComputesFinalResidual(SNES, PetscBool);
574 PETSC_EXTERN PetscErrorCode SNESGetAlwaysComputesFinalResidual(SNES, PetscBool *);
575 
576 PETSC_EXTERN PetscErrorCode SNESShellGetContext(SNES, void *);
577 PETSC_EXTERN PetscErrorCode SNESShellSetContext(SNES, void *);
578 PETSC_EXTERN PetscErrorCode SNESShellSetSolve(SNES, PetscErrorCode (*)(SNES, Vec));
579 
580 /* --------- Routines specifically for line search methods --------------- */
581 
582 /*S
583      SNESLineSearch - Abstract PETSc object that manages line-search operations for nonlinear solvers
584 
585    Level: beginner
586 
587 .seealso: [](chapter_snes), `SNESLineSearchType`, `SNESLineSearchCreate()`, `SNESLineSearchSetType()`, `SNES`
588 S*/
589 typedef struct _p_LineSearch *SNESLineSearch;
590 
591 /*J
592     SNESLineSearchType - String with the name of a PETSc line search method `SNESLineSearch`
593 
594    Level: beginner
595 
596 .seealso: [](chapter_snes), `SNESLineSearch`, `SNESLineSearchSetType()`, `SNES`
597 J*/
598 typedef const char *SNESLineSearchType;
599 #define SNESLINESEARCHBT        "bt"
600 #define SNESLINESEARCHNLEQERR   "nleqerr"
601 #define SNESLINESEARCHBASIC     "basic"
602 #define SNESLINESEARCHNONE      "none"
603 #define SNESLINESEARCHL2        "l2"
604 #define SNESLINESEARCHCP        "cp"
605 #define SNESLINESEARCHSHELL     "shell"
606 #define SNESLINESEARCHNCGLINEAR "ncglinear"
607 
608 PETSC_EXTERN PetscFunctionList SNESList;
609 PETSC_EXTERN PetscClassId      SNESLINESEARCH_CLASSID;
610 PETSC_EXTERN PetscFunctionList SNESLineSearchList;
611 
612 #define SNES_LINESEARCH_ORDER_LINEAR    1
613 #define SNES_LINESEARCH_ORDER_QUADRATIC 2
614 #define SNES_LINESEARCH_ORDER_CUBIC     3
615 
616 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVIProjectFunc)(SNES, Vec);
617 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVINormFunc)(SNES, Vec, Vec, PetscReal *);
618 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchApplyFunc)(SNESLineSearch);
619 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchUserFunc)(SNESLineSearch, void *);
620 
621 PETSC_EXTERN PetscErrorCode SNESLineSearchCreate(MPI_Comm, SNESLineSearch *);
622 PETSC_EXTERN PetscErrorCode SNESLineSearchReset(SNESLineSearch);
623 PETSC_EXTERN PetscErrorCode SNESLineSearchView(SNESLineSearch, PetscViewer);
624 PETSC_EXTERN PetscErrorCode SNESLineSearchDestroy(SNESLineSearch *);
625 PETSC_EXTERN PetscErrorCode SNESLineSearchGetType(SNESLineSearch, SNESLineSearchType *);
626 PETSC_EXTERN PetscErrorCode SNESLineSearchSetType(SNESLineSearch, SNESLineSearchType);
627 PETSC_EXTERN PetscErrorCode SNESLineSearchSetFromOptions(SNESLineSearch);
628 PETSC_EXTERN PetscErrorCode SNESLineSearchSetFunction(SNESLineSearch, PetscErrorCode (*)(SNES, Vec, Vec));
629 PETSC_EXTERN PetscErrorCode SNESLineSearchSetUp(SNESLineSearch);
630 PETSC_EXTERN PetscErrorCode SNESLineSearchApply(SNESLineSearch, Vec, Vec, PetscReal *, Vec);
631 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheck(SNESLineSearch, Vec, Vec, PetscBool *);
632 PETSC_EXTERN PetscErrorCode SNESLineSearchPostCheck(SNESLineSearch, Vec, Vec, Vec, PetscBool *, PetscBool *);
633 PETSC_EXTERN PetscErrorCode SNESLineSearchSetWorkVecs(SNESLineSearch, PetscInt);
634 
635 /* set the functions for precheck and postcheck */
636 
637 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPreCheck(SNESLineSearch, PetscErrorCode (*)(SNESLineSearch, Vec, Vec, PetscBool *, void *), void *ctx);
638 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPostCheck(SNESLineSearch, PetscErrorCode (*)(SNESLineSearch, Vec, Vec, Vec, PetscBool *, PetscBool *, void *), void *ctx);
639 
640 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPreCheck(SNESLineSearch, PetscErrorCode (**)(SNESLineSearch, Vec, Vec, PetscBool *, void *), void **ctx);
641 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPostCheck(SNESLineSearch, PetscErrorCode (**)(SNESLineSearch, Vec, Vec, Vec, PetscBool *, PetscBool *, void *), void **ctx);
642 
643 /* set the functions for VI-specific line search operations */
644 
645 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc, SNESLineSearchVINormFunc);
646 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc *, SNESLineSearchVINormFunc *);
647 
648 /* pointers to the associated SNES in order to be able to get the function evaluation out */
649 PETSC_EXTERN PetscErrorCode SNESLineSearchSetSNES(SNESLineSearch, SNES);
650 PETSC_EXTERN PetscErrorCode SNESLineSearchGetSNES(SNESLineSearch, SNES *);
651 
652 /* set and get the parameters and vectors */
653 PETSC_EXTERN PetscErrorCode SNESLineSearchGetTolerances(SNESLineSearch, PetscReal *, PetscReal *, PetscReal *, PetscReal *, PetscReal *, PetscInt *);
654 PETSC_EXTERN PetscErrorCode SNESLineSearchSetTolerances(SNESLineSearch, PetscReal, PetscReal, PetscReal, PetscReal, PetscReal, PetscInt);
655 
656 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheckPicard(SNESLineSearch, Vec, Vec, PetscBool *, void *);
657 
658 PETSC_EXTERN PetscErrorCode SNESLineSearchGetLambda(SNESLineSearch, PetscReal *);
659 PETSC_EXTERN PetscErrorCode SNESLineSearchSetLambda(SNESLineSearch, PetscReal);
660 
661 PETSC_EXTERN PetscErrorCode SNESLineSearchGetDamping(SNESLineSearch, PetscReal *);
662 PETSC_EXTERN PetscErrorCode SNESLineSearchSetDamping(SNESLineSearch, PetscReal);
663 
664 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOrder(SNESLineSearch, PetscInt *order);
665 PETSC_EXTERN PetscErrorCode SNESLineSearchSetOrder(SNESLineSearch, PetscInt order);
666 
667 /*E
668     SNESLineSearchReason - indication if the line search has succeeded or failed and why
669 
670   Values:
671 +  `SNES_LINESEARCH_SUCCEEDED` - the line search succeeded
672 .  `SNES_LINESEARCH_FAILED_NANORINF` - a not a number of infinity appeared in the computions
673 .  `SNES_LINESEARCH_FAILED_DOMAIN` - the function was evaluated outside of its domain, see `SNESSetFunctionDomainError()` and `SNESSetJacobianDomainError()`
674 .  `SNES_LINESEARCH_FAILED_REDUCT` - the linear search failed to get the requested decrease in its norm or objective
675 .  `SNES_LINESEARCH_FAILED_USER` - used by `SNESLINESEARCHNLEQERR` to indicate the user changed the search direction inappropriately
676 -  `SNES_LINESEARCH_FAILED_FUNCTION` - indicates the maximum number of function evaluations allowed has been surpassed, `SNESConvergedReason` is also
677                                      set to `SNES_DIVERGED_FUNCTION_COUNT`
678 
679    Level: intermediate
680 
681    Developer Note:
682    Some of these reasons overlap with values of `SNESConvergedReason`
683 
684 .seealso: [](chapter_snes), `SNES`, `SNESSolve()`, `SNESGetConvergedReason()`, `KSPConvergedReason`, `SNESSetConvergenceTest()`,
685           `SNESSetFunctionDomainError()` and `SNESSetJacobianDomainError()`
686 E*/
687 typedef enum {
688   SNES_LINESEARCH_SUCCEEDED,
689   SNES_LINESEARCH_FAILED_NANORINF,
690   SNES_LINESEARCH_FAILED_DOMAIN,
691   SNES_LINESEARCH_FAILED_REDUCT, /* INSUFFICIENT REDUCTION */
692   SNES_LINESEARCH_FAILED_USER,
693   SNES_LINESEARCH_FAILED_FUNCTION
694 } SNESLineSearchReason;
695 
696 PETSC_EXTERN PetscErrorCode SNESLineSearchGetReason(SNESLineSearch, SNESLineSearchReason *);
697 PETSC_EXTERN PetscErrorCode SNESLineSearchSetReason(SNESLineSearch, SNESLineSearchReason);
698 
699 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVecs(SNESLineSearch, Vec *, Vec *, Vec *, Vec *, Vec *);
700 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVecs(SNESLineSearch, Vec, Vec, Vec, Vec, Vec);
701 
702 PETSC_EXTERN PetscErrorCode SNESLineSearchGetNorms(SNESLineSearch, PetscReal *, PetscReal *, PetscReal *);
703 PETSC_EXTERN PetscErrorCode SNESLineSearchSetNorms(SNESLineSearch, PetscReal, PetscReal, PetscReal);
704 PETSC_EXTERN PetscErrorCode SNESLineSearchComputeNorms(SNESLineSearch);
705 PETSC_EXTERN PetscErrorCode SNESLineSearchSetComputeNorms(SNESLineSearch, PetscBool);
706 
707 PETSC_EXTERN PetscErrorCode SNESLineSearchMonitor(SNESLineSearch);
708 PETSC_EXTERN PetscErrorCode SNESLineSearchMonitorSet(SNESLineSearch, PetscErrorCode (*)(SNESLineSearch, void *), void *, PetscErrorCode (*)(void **));
709 PETSC_EXTERN PetscErrorCode SNESLineSearchMonitorSetFromOptions(SNESLineSearch, const char[], const char[], const char[], PetscErrorCode (*)(SNESLineSearch, PetscViewerAndFormat *), PetscErrorCode (*)(SNESLineSearch, PetscViewerAndFormat *));
710 PETSC_EXTERN PetscErrorCode SNESLineSearchMonitorCancel(SNESLineSearch);
711 PETSC_EXTERN PetscErrorCode SNESLineSearchMonitorUpdate(SNESLineSearch, PetscViewerAndFormat *);
712 PETSC_EXTERN PetscErrorCode SNESLineSearchSetDefaultMonitor(SNESLineSearch, PetscViewer);
713 PETSC_EXTERN PetscErrorCode SNESLineSearchGetDefaultMonitor(SNESLineSearch, PetscViewer *);
714 PETSC_EXTERN PetscErrorCode SNESLineSearchMonitorSolutionUpdate(SNESLineSearch, PetscViewerAndFormat *);
715 
716 PETSC_EXTERN PetscErrorCode SNESLineSearchAppendOptionsPrefix(SNESLineSearch, const char prefix[]);
717 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOptionsPrefix(SNESLineSearch, const char *prefix[]);
718 
719 /* Shell interface functions */
720 PETSC_EXTERN PetscErrorCode SNESLineSearchShellSetUserFunc(SNESLineSearch, SNESLineSearchUserFunc, void *);
721 PETSC_EXTERN PetscErrorCode SNESLineSearchShellGetUserFunc(SNESLineSearch, SNESLineSearchUserFunc *, void **);
722 
723 /* BT interface functions */
724 PETSC_EXTERN PetscErrorCode SNESLineSearchBTSetAlpha(SNESLineSearch, PetscReal);
725 PETSC_EXTERN PetscErrorCode SNESLineSearchBTGetAlpha(SNESLineSearch, PetscReal *);
726 
727 /*register line search types */
728 PETSC_EXTERN PetscErrorCode SNESLineSearchRegister(const char[], PetscErrorCode (*)(SNESLineSearch));
729 
730 /* Routines for VI solver */
731 PETSC_EXTERN PetscErrorCode SNESVISetVariableBounds(SNES, Vec, Vec);
732 PETSC_EXTERN PetscErrorCode SNESVIGetVariableBounds(SNES, Vec *, Vec *);
733 PETSC_EXTERN PetscErrorCode SNESVISetComputeVariableBounds(SNES, PetscErrorCode (*)(SNES, Vec, Vec));
734 PETSC_EXTERN PetscErrorCode SNESVIGetInactiveSet(SNES, IS *);
735 PETSC_EXTERN PetscErrorCode SNESVIGetActiveSetIS(SNES, Vec, Vec, IS *);
736 PETSC_EXTERN PetscErrorCode SNESVIComputeInactiveSetFnorm(SNES, Vec, Vec, PetscReal *);
737 PETSC_EXTERN PetscErrorCode SNESVISetRedundancyCheck(SNES, PetscErrorCode (*)(SNES, IS, IS *, void *), void *);
738 PETSC_EXTERN PetscErrorCode SNESVIComputeMeritFunction(Vec, PetscReal *, PetscReal *);
739 PETSC_EXTERN PetscErrorCode SNESVIComputeFunction(SNES, Vec, Vec, void *);
740 PETSC_EXTERN PetscErrorCode DMSetVI(DM, IS);
741 PETSC_EXTERN PetscErrorCode DMDestroyVI(DM);
742 
743 PETSC_EXTERN PetscErrorCode SNESTestLocalMin(SNES);
744 
745 /* Should this routine be private? */
746 PETSC_EXTERN PetscErrorCode SNESComputeJacobian(SNES, Vec, Mat, Mat);
747 PETSC_EXTERN PetscErrorCode SNESTestJacobian(SNES);
748 
749 PETSC_EXTERN PetscErrorCode SNESSetDM(SNES, DM);
750 PETSC_EXTERN PetscErrorCode SNESGetDM(SNES, DM *);
751 PETSC_EXTERN PetscErrorCode SNESSetNPC(SNES, SNES);
752 PETSC_EXTERN PetscErrorCode SNESGetNPC(SNES, SNES *);
753 PETSC_EXTERN PetscErrorCode SNESHasNPC(SNES, PetscBool *);
754 PETSC_EXTERN PetscErrorCode SNESApplyNPC(SNES, Vec, Vec, Vec);
755 PETSC_EXTERN PetscErrorCode SNESGetNPCFunction(SNES, Vec, PetscReal *);
756 PETSC_EXTERN PetscErrorCode SNESComputeFunctionDefaultNPC(SNES, Vec, Vec);
757 PETSC_EXTERN PetscErrorCode SNESSetNPCSide(SNES, PCSide);
758 PETSC_EXTERN PetscErrorCode SNESGetNPCSide(SNES, PCSide *);
759 PETSC_EXTERN PetscErrorCode SNESSetLineSearch(SNES, SNESLineSearch);
760 PETSC_EXTERN PetscErrorCode SNESGetLineSearch(SNES, SNESLineSearch *);
761 PETSC_EXTERN PetscErrorCode SNESRestrictHookAdd(SNES, PetscErrorCode (*)(SNES, SNES, void *), void *);
762 
763 PETSC_DEPRECATED_FUNCTION("Use SNESGetLineSearch() (since version 3.4)") static inline PetscErrorCode SNESGetSNESLineSearch(SNES snes, SNESLineSearch *ls)
764 {
765   return SNESGetLineSearch(snes, ls);
766 }
767 PETSC_DEPRECATED_FUNCTION("Use SNESSetLineSearch() (since version 3.4)") static inline PetscErrorCode SNESSetSNESLineSearch(SNES snes, SNESLineSearch ls)
768 {
769   return SNESSetLineSearch(snes, ls);
770 }
771 
772 PETSC_EXTERN PetscErrorCode SNESSetUpMatrices(SNES);
773 PETSC_EXTERN PetscErrorCode DMSNESSetFunction(DM, PetscErrorCode (*)(SNES, Vec, Vec, void *), void *);
774 PETSC_EXTERN PetscErrorCode DMSNESGetFunction(DM, PetscErrorCode (**)(SNES, Vec, Vec, void *), void **);
775 PETSC_EXTERN PetscErrorCode DMSNESSetFunctionContextDestroy(DM, PetscErrorCode (*)(void *));
776 PETSC_EXTERN PetscErrorCode DMSNESSetMFFunction(DM, PetscErrorCode (*)(SNES, Vec, Vec, void *), void *);
777 PETSC_EXTERN PetscErrorCode DMSNESSetNGS(DM, PetscErrorCode (*)(SNES, Vec, Vec, void *), void *);
778 PETSC_EXTERN PetscErrorCode DMSNESGetNGS(DM, PetscErrorCode (**)(SNES, Vec, Vec, void *), void **);
779 PETSC_EXTERN PetscErrorCode DMSNESSetJacobian(DM, PetscErrorCode (*)(SNES, Vec, Mat, Mat, void *), void *);
780 PETSC_EXTERN PetscErrorCode DMSNESGetJacobian(DM, PetscErrorCode (**)(SNES, Vec, Mat, Mat, void *), void **);
781 PETSC_EXTERN PetscErrorCode DMSNESSetJacobianContextDestroy(DM, PetscErrorCode (*)(void *));
782 PETSC_EXTERN PetscErrorCode DMSNESSetPicard(DM, PetscErrorCode (*)(SNES, Vec, Vec, void *), PetscErrorCode (*)(SNES, Vec, Mat, Mat, void *), void *);
783 PETSC_EXTERN PetscErrorCode DMSNESGetPicard(DM, PetscErrorCode (**)(SNES, Vec, Vec, void *), PetscErrorCode (**)(SNES, Vec, Mat, Mat, void *), void **);
784 PETSC_EXTERN PetscErrorCode DMSNESSetObjective(DM, PetscErrorCode (*)(SNES, Vec, PetscReal *, void *), void *);
785 PETSC_EXTERN PetscErrorCode DMSNESGetObjective(DM, PetscErrorCode (**)(SNES, Vec, PetscReal *, void *), void **);
786 PETSC_EXTERN PetscErrorCode DMCopyDMSNES(DM, DM);
787 
788 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESFunction)(DMDALocalInfo *, void *, void *, void *);
789 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESJacobian)(DMDALocalInfo *, void *, Mat, Mat, void *);
790 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESObjective)(DMDALocalInfo *, void *, PetscReal *, void *);
791 
792 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESFunctionVec)(DMDALocalInfo *, Vec, Vec, void *);
793 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESJacobianVec)(DMDALocalInfo *, Vec, Mat, Mat, void *);
794 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESObjectiveVec)(DMDALocalInfo *, Vec, PetscReal *, void *);
795 
796 PETSC_EXTERN PetscErrorCode DMDASNESSetFunctionLocal(DM, InsertMode, DMDASNESFunction, void *);
797 PETSC_EXTERN PetscErrorCode DMDASNESSetJacobianLocal(DM, DMDASNESJacobian, void *);
798 PETSC_EXTERN PetscErrorCode DMDASNESSetObjectiveLocal(DM, DMDASNESObjective, void *);
799 PETSC_EXTERN PetscErrorCode DMDASNESSetPicardLocal(DM, InsertMode, PetscErrorCode (*)(DMDALocalInfo *, void *, void *, void *), PetscErrorCode (*)(DMDALocalInfo *, void *, Mat, Mat, void *), void *);
800 
801 PETSC_EXTERN PetscErrorCode DMDASNESSetFunctionLocalVec(DM, InsertMode, DMDASNESFunctionVec, void *);
802 PETSC_EXTERN PetscErrorCode DMDASNESSetJacobianLocalVec(DM, DMDASNESJacobianVec, void *);
803 PETSC_EXTERN PetscErrorCode DMDASNESSetObjectiveLocalVec(DM, DMDASNESObjectiveVec, void *);
804 
805 PETSC_EXTERN PetscErrorCode DMSNESSetBoundaryLocal(DM, PetscErrorCode (*)(DM, Vec, void *), void *);
806 PETSC_EXTERN PetscErrorCode DMSNESSetFunctionLocal(DM, PetscErrorCode (*)(DM, Vec, Vec, void *), void *);
807 PETSC_EXTERN PetscErrorCode DMSNESSetJacobianLocal(DM, PetscErrorCode (*)(DM, Vec, Mat, Mat, void *), void *);
808 PETSC_EXTERN PetscErrorCode DMSNESGetBoundaryLocal(DM, PetscErrorCode (**)(DM, Vec, void *), void **);
809 PETSC_EXTERN PetscErrorCode DMSNESGetFunctionLocal(DM, PetscErrorCode (**)(DM, Vec, Vec, void *), void **);
810 PETSC_EXTERN PetscErrorCode DMSNESGetJacobianLocal(DM, PetscErrorCode (**)(DM, Vec, Mat, Mat, void *), void **);
811 
812 /* Routines for Multiblock solver */
813 PETSC_EXTERN PetscErrorCode SNESMultiblockSetFields(SNES, const char[], PetscInt, const PetscInt *);
814 PETSC_EXTERN PetscErrorCode SNESMultiblockSetIS(SNES, const char[], IS);
815 PETSC_EXTERN PetscErrorCode SNESMultiblockSetBlockSize(SNES, PetscInt);
816 PETSC_EXTERN PetscErrorCode SNESMultiblockSetType(SNES, PCCompositeType);
817 
818 /*J
819     SNESMSType - String with the name of a PETSc `SNESMS` method.
820 
821    Level: intermediate
822 
823 .seealso: [](chapter_snes), `SNESMS`, `SNESMSGetType()`, `SNESMSSetType()`, `SNES`
824 J*/
825 typedef const char *SNESMSType;
826 #define SNESMSM62       "m62"
827 #define SNESMSEULER     "euler"
828 #define SNESMSJAMESON83 "jameson83"
829 #define SNESMSVLTP11    "vltp11"
830 #define SNESMSVLTP21    "vltp21"
831 #define SNESMSVLTP31    "vltp31"
832 #define SNESMSVLTP41    "vltp41"
833 #define SNESMSVLTP51    "vltp51"
834 #define SNESMSVLTP61    "vltp61"
835 
836 PETSC_EXTERN PetscErrorCode SNESMSRegister(SNESMSType, PetscInt, PetscInt, PetscReal, const PetscReal[], const PetscReal[], const PetscReal[]);
837 PETSC_EXTERN PetscErrorCode SNESMSGetType(SNES, SNESMSType *);
838 PETSC_EXTERN PetscErrorCode SNESMSSetType(SNES, SNESMSType);
839 PETSC_EXTERN PetscErrorCode SNESMSGetDamping(SNES, PetscReal *);
840 PETSC_EXTERN PetscErrorCode SNESMSSetDamping(SNES, PetscReal);
841 PETSC_EXTERN PetscErrorCode SNESMSFinalizePackage(void);
842 PETSC_EXTERN PetscErrorCode SNESMSInitializePackage(void);
843 PETSC_EXTERN PetscErrorCode SNESMSRegisterDestroy(void);
844 
845 /* routines for NGMRES solver */
846 
847 typedef enum {
848   SNES_NGMRES_RESTART_NONE       = 0,
849   SNES_NGMRES_RESTART_PERIODIC   = 1,
850   SNES_NGMRES_RESTART_DIFFERENCE = 2
851 } SNESNGMRESRestartType;
852 PETSC_EXTERN const char *const SNESNGMRESRestartTypes[];
853 
854 typedef enum {
855   SNES_NGMRES_SELECT_NONE       = 0,
856   SNES_NGMRES_SELECT_DIFFERENCE = 1,
857   SNES_NGMRES_SELECT_LINESEARCH = 2
858 } SNESNGMRESSelectType;
859 PETSC_EXTERN const char *const SNESNGMRESSelectTypes[];
860 
861 PETSC_EXTERN PetscErrorCode SNESNGMRESSetRestartType(SNES, SNESNGMRESRestartType);
862 PETSC_EXTERN PetscErrorCode SNESNGMRESSetSelectType(SNES, SNESNGMRESSelectType);
863 PETSC_EXTERN PetscErrorCode SNESNGMRESSetRestartFmRise(SNES, PetscBool);
864 PETSC_EXTERN PetscErrorCode SNESNGMRESGetRestartFmRise(SNES, PetscBool *);
865 
866 /* routines for NCG solver */
867 
868 typedef enum {
869   SNES_NCG_FR  = 0,
870   SNES_NCG_PRP = 1,
871   SNES_NCG_HS  = 2,
872   SNES_NCG_DY  = 3,
873   SNES_NCG_CD  = 4
874 } SNESNCGType;
875 PETSC_EXTERN const char *const SNESNCGTypes[];
876 
877 PETSC_EXTERN PetscErrorCode SNESNCGSetType(SNES, SNESNCGType);
878 
879 typedef enum {
880   SNES_QN_SCALE_DEFAULT  = 0,
881   SNES_QN_SCALE_NONE     = 1,
882   SNES_QN_SCALE_SCALAR   = 2,
883   SNES_QN_SCALE_DIAGONAL = 3,
884   SNES_QN_SCALE_JACOBIAN = 4
885 } SNESQNScaleType;
886 PETSC_EXTERN const char *const SNESQNScaleTypes[];
887 typedef enum {
888   SNES_QN_RESTART_DEFAULT  = 0,
889   SNES_QN_RESTART_NONE     = 1,
890   SNES_QN_RESTART_POWELL   = 2,
891   SNES_QN_RESTART_PERIODIC = 3
892 } SNESQNRestartType;
893 PETSC_EXTERN const char *const SNESQNRestartTypes[];
894 typedef enum {
895   SNES_QN_LBFGS      = 0,
896   SNES_QN_BROYDEN    = 1,
897   SNES_QN_BADBROYDEN = 2
898 } SNESQNType;
899 PETSC_EXTERN const char *const SNESQNTypes[];
900 
901 PETSC_EXTERN PetscErrorCode SNESQNSetType(SNES, SNESQNType);
902 PETSC_EXTERN PetscErrorCode SNESQNSetScaleType(SNES, SNESQNScaleType);
903 PETSC_EXTERN PetscErrorCode SNESQNSetRestartType(SNES, SNESQNRestartType);
904 
905 PETSC_EXTERN PetscErrorCode SNESNASMGetType(SNES, PCASMType *);
906 PETSC_EXTERN PetscErrorCode SNESNASMSetType(SNES, PCASMType);
907 PETSC_EXTERN PetscErrorCode SNESNASMGetSubdomains(SNES, PetscInt *, SNES **, VecScatter **, VecScatter **, VecScatter **);
908 PETSC_EXTERN PetscErrorCode SNESNASMSetSubdomains(SNES, PetscInt, SNES *, VecScatter *, VecScatter *, VecScatter *);
909 PETSC_EXTERN PetscErrorCode SNESNASMSetDamping(SNES, PetscReal);
910 PETSC_EXTERN PetscErrorCode SNESNASMGetDamping(SNES, PetscReal *);
911 PETSC_EXTERN PetscErrorCode SNESNASMGetSubdomainVecs(SNES, PetscInt *, Vec **, Vec **, Vec **, Vec **);
912 PETSC_EXTERN PetscErrorCode SNESNASMSetComputeFinalJacobian(SNES, PetscBool);
913 PETSC_EXTERN PetscErrorCode SNESNASMGetSNES(SNES, PetscInt, SNES *);
914 PETSC_EXTERN PetscErrorCode SNESNASMGetNumber(SNES, PetscInt *);
915 PETSC_EXTERN PetscErrorCode SNESNASMSetWeight(SNES, Vec);
916 
917 typedef enum {
918   SNES_COMPOSITE_ADDITIVE,
919   SNES_COMPOSITE_MULTIPLICATIVE,
920   SNES_COMPOSITE_ADDITIVEOPTIMAL
921 } SNESCompositeType;
922 PETSC_EXTERN const char *const SNESCompositeTypes[];
923 
924 PETSC_EXTERN PetscErrorCode SNESCompositeSetType(SNES, SNESCompositeType);
925 PETSC_EXTERN PetscErrorCode SNESCompositeAddSNES(SNES, SNESType);
926 PETSC_EXTERN PetscErrorCode SNESCompositeGetSNES(SNES, PetscInt, SNES *);
927 PETSC_EXTERN PetscErrorCode SNESCompositeGetNumber(SNES, PetscInt *);
928 PETSC_EXTERN PetscErrorCode SNESCompositeSetDamping(SNES, PetscInt, PetscReal);
929 
930 PETSC_EXTERN PetscErrorCode SNESPatchSetDiscretisationInfo(SNES, PetscInt, DM *, PetscInt *, PetscInt *, const PetscInt **, const PetscInt *, PetscInt, const PetscInt *, PetscInt, const PetscInt *);
931 PETSC_EXTERN PetscErrorCode SNESPatchSetComputeOperator(SNES, PetscErrorCode (*func)(PC, PetscInt, Vec, Mat, IS, PetscInt, const PetscInt *, const PetscInt *, void *), void *);
932 PETSC_EXTERN PetscErrorCode SNESPatchSetComputeFunction(SNES, PetscErrorCode (*func)(PC, PetscInt, Vec, Vec, IS, PetscInt, const PetscInt *, const PetscInt *, void *), void *);
933 PETSC_EXTERN PetscErrorCode SNESPatchSetConstructType(SNES, PCPatchConstructType, PetscErrorCode (*func)(PC, PetscInt *, IS **, IS *, void *), void *);
934 PETSC_EXTERN PetscErrorCode SNESPatchSetCellNumbering(SNES, PetscSection);
935 
936 /*E
937     SNESFASType - Determines the type of nonlinear multigrid method that is run.
938 
939    Values:
940 +  `SNES_FAS_MULTIPLICATIVE` (default) - traditional V or W cycle as determined by `SNESFASSetCycles()`
941 .  `SNES_FAS_ADDITIVE`                 - additive FAS cycle
942 .  `SNES_FAS_FULL`                     - full FAS cycle
943 -  `SNES_FAS_KASKADE`                  - Kaskade FAS cycle
944 
945    Level: beginner
946 
947 .seealso: [](chapter_snes), `SNESFAS`, `PCMGSetType()`, `PCMGType`
948 E*/
949 typedef enum {
950   SNES_FAS_MULTIPLICATIVE,
951   SNES_FAS_ADDITIVE,
952   SNES_FAS_FULL,
953   SNES_FAS_KASKADE
954 } SNESFASType;
955 PETSC_EXTERN const char *const SNESFASTypes[];
956 
957 /* called on the finest level FAS instance*/
958 PETSC_EXTERN PetscErrorCode SNESFASSetType(SNES, SNESFASType);
959 PETSC_EXTERN PetscErrorCode SNESFASGetType(SNES, SNESFASType *);
960 PETSC_EXTERN PetscErrorCode SNESFASSetLevels(SNES, PetscInt, MPI_Comm *);
961 PETSC_EXTERN PetscErrorCode SNESFASGetLevels(SNES, PetscInt *);
962 PETSC_EXTERN PetscErrorCode SNESFASGetCycleSNES(SNES, PetscInt, SNES *);
963 PETSC_EXTERN PetscErrorCode SNESFASSetNumberSmoothUp(SNES, PetscInt);
964 PETSC_EXTERN PetscErrorCode SNESFASSetNumberSmoothDown(SNES, PetscInt);
965 PETSC_EXTERN PetscErrorCode SNESFASSetCycles(SNES, PetscInt);
966 PETSC_EXTERN PetscErrorCode SNESFASSetMonitor(SNES, PetscViewerAndFormat *, PetscBool);
967 PETSC_EXTERN PetscErrorCode SNESFASSetLog(SNES, PetscBool);
968 
969 PETSC_EXTERN PetscErrorCode SNESFASSetGalerkin(SNES, PetscBool);
970 PETSC_EXTERN PetscErrorCode SNESFASGetGalerkin(SNES, PetscBool *);
971 PETSC_EXTERN PetscErrorCode SNESFASGalerkinFunctionDefault(SNES, Vec, Vec, void *);
972 
973 /* called on any level -- "Cycle" FAS instance */
974 PETSC_EXTERN PetscErrorCode SNESFASCycleGetSmoother(SNES, SNES *);
975 PETSC_EXTERN PetscErrorCode SNESFASCycleGetSmootherUp(SNES, SNES *);
976 PETSC_EXTERN PetscErrorCode SNESFASCycleGetSmootherDown(SNES, SNES *);
977 PETSC_EXTERN PetscErrorCode SNESFASCycleGetCorrection(SNES, SNES *);
978 PETSC_EXTERN PetscErrorCode SNESFASCycleGetInterpolation(SNES, Mat *);
979 PETSC_EXTERN PetscErrorCode SNESFASCycleGetRestriction(SNES, Mat *);
980 PETSC_EXTERN PetscErrorCode SNESFASCycleGetInjection(SNES, Mat *);
981 PETSC_EXTERN PetscErrorCode SNESFASCycleGetRScale(SNES, Vec *);
982 PETSC_EXTERN PetscErrorCode SNESFASCycleSetCycles(SNES, PetscInt);
983 PETSC_EXTERN PetscErrorCode SNESFASCycleIsFine(SNES, PetscBool *);
984 
985 /* called on the (outer) finest level FAS to set/get parameters on any level instance */
986 PETSC_EXTERN PetscErrorCode SNESFASSetInterpolation(SNES, PetscInt, Mat);
987 PETSC_EXTERN PetscErrorCode SNESFASGetInterpolation(SNES, PetscInt, Mat *);
988 PETSC_EXTERN PetscErrorCode SNESFASSetRestriction(SNES, PetscInt, Mat);
989 PETSC_EXTERN PetscErrorCode SNESFASGetRestriction(SNES, PetscInt, Mat *);
990 PETSC_EXTERN PetscErrorCode SNESFASSetInjection(SNES, PetscInt, Mat);
991 PETSC_EXTERN PetscErrorCode SNESFASGetInjection(SNES, PetscInt, Mat *);
992 PETSC_EXTERN PetscErrorCode SNESFASSetRScale(SNES, PetscInt, Vec);
993 PETSC_EXTERN PetscErrorCode SNESFASGetRScale(SNES, PetscInt, Vec *);
994 PETSC_EXTERN PetscErrorCode SNESFASSetContinuation(SNES, PetscBool);
995 
996 PETSC_EXTERN PetscErrorCode SNESFASGetSmoother(SNES, PetscInt, SNES *);
997 PETSC_EXTERN PetscErrorCode SNESFASGetSmootherUp(SNES, PetscInt, SNES *);
998 PETSC_EXTERN PetscErrorCode SNESFASGetSmootherDown(SNES, PetscInt, SNES *);
999 PETSC_EXTERN PetscErrorCode SNESFASGetCoarseSolve(SNES, SNES *);
1000 
1001 /* parameters for full FAS */
1002 PETSC_EXTERN PetscErrorCode SNESFASFullSetDownSweep(SNES, PetscBool);
1003 PETSC_EXTERN PetscErrorCode SNESFASCreateCoarseVec(SNES, Vec *);
1004 PETSC_EXTERN PetscErrorCode SNESFASRestrict(SNES, Vec, Vec);
1005 PETSC_EXTERN PetscErrorCode SNESFASFullSetTotal(SNES, PetscBool);
1006 PETSC_EXTERN PetscErrorCode SNESFASFullGetTotal(SNES, PetscBool *);
1007 
1008 PETSC_EXTERN PetscErrorCode DMSNESCheckDiscretization(SNES, DM, PetscReal, Vec, PetscReal, PetscReal[]);
1009 PETSC_EXTERN PetscErrorCode DMSNESCheckResidual(SNES, DM, Vec, PetscReal, PetscReal *);
1010 PETSC_EXTERN PetscErrorCode DMSNESCheckJacobian(SNES, DM, Vec, PetscReal, PetscBool *, PetscReal *);
1011 PETSC_EXTERN PetscErrorCode DMSNESCheckFromOptions(SNES, Vec);
1012 PETSC_EXTERN PetscErrorCode DMSNESComputeJacobianAction(DM, Vec, Vec, Vec, void *);
1013 PETSC_EXTERN PetscErrorCode DMSNESCreateJacobianMF(DM, Vec, void *, Mat *);
1014 
1015 #endif
1016