xref: /petsc/include/petscsnes.h (revision c02fb785c06e0fd264f23f73b6efa4eea02fd6ab) 
1 /*
2     User interface for the nonlinear solvers package.
3 */
4 #if !defined(__PETSCSNES_H)
5 #define __PETSCSNES_H
6 #include <petscksp.h>
7 #include <petscdmtypes.h>
8 #include <petscdmdatypes.h>
9 
10 /*S
11      SNES - Abstract PETSc object that manages all nonlinear solves
12 
13    Level: beginner
14 
15   Concepts: nonlinear solvers
16 
17 .seealso:  SNESCreate(), SNESSetType(), SNESType, TS, KSP, KSP, PC, SNESDestroy()
18 S*/
19 typedef struct _p_SNES* SNES;
20 
21 /*J
22     SNESType - String with the name of a PETSc SNES method.
23 
24    Level: beginner
25 
26 .seealso: SNESSetType(), SNES, SNESCreate(), SNESDestroy(), SNESSetFromOptions()
27 J*/
28 typedef const char* SNESType;
29 #define SNESNEWTONLS     "newtonls"
30 #define SNESNEWTONTR     "newtontr"
31 #define SNESPYTHON       "python"
32 #define SNESTEST         "test"
33 #define SNESNRICHARDSON  "nrichardson"
34 #define SNESKSPONLY      "ksponly"
35 #define SNESVINEWTONRSLS "vinewtonrsls"
36 #define SNESVINEWTONSSLS "vinewtonssls"
37 #define SNESNGMRES       "ngmres"
38 #define SNESQN           "qn"
39 #define SNESSHELL        "shell"
40 #define SNESGS           "gs"
41 #define SNESNCG          "ncg"
42 #define SNESFAS          "fas"
43 #define SNESMS           "ms"
44 #define SNESNASM         "nasm"
45 #define SNESANDERSON     "anderson"
46 #define SNESASPIN        "aspin"
47 #define SNESCOMPOSITE    "composite"
48 
49 /* Logging support */
50 PETSC_EXTERN PetscClassId SNES_CLASSID;
51 PETSC_EXTERN PetscClassId DMSNES_CLASSID;
52 
53 PETSC_EXTERN PetscErrorCode SNESInitializePackage(void);
54 
55 PETSC_EXTERN PetscErrorCode SNESCreate(MPI_Comm,SNES*);
56 PETSC_EXTERN PetscErrorCode SNESReset(SNES);
57 PETSC_EXTERN PetscErrorCode SNESDestroy(SNES*);
58 PETSC_EXTERN PetscErrorCode SNESSetType(SNES,SNESType);
59 PETSC_EXTERN PetscErrorCode SNESMonitor(SNES,PetscInt,PetscReal);
60 PETSC_EXTERN PetscErrorCode SNESMonitorSet(SNES,PetscErrorCode(*)(SNES,PetscInt,PetscReal,void*),void *,PetscErrorCode (*)(void**));
61 PETSC_EXTERN PetscErrorCode SNESMonitorCancel(SNES);
62 PETSC_EXTERN PetscErrorCode SNESSetConvergenceHistory(SNES,PetscReal[],PetscInt[],PetscInt,PetscBool );
63 PETSC_EXTERN PetscErrorCode SNESGetConvergenceHistory(SNES,PetscReal*[],PetscInt *[],PetscInt *);
64 PETSC_EXTERN PetscErrorCode SNESSetUp(SNES);
65 PETSC_EXTERN PetscErrorCode SNESSolve(SNES,Vec,Vec);
66 PETSC_EXTERN PetscErrorCode SNESSetErrorIfNotConverged(SNES,PetscBool );
67 PETSC_EXTERN PetscErrorCode SNESGetErrorIfNotConverged(SNES,PetscBool  *);
68 
69 PETSC_EXTERN PetscErrorCode SNESSetWorkVecs(SNES,PetscInt);
70 
71 PETSC_EXTERN PetscErrorCode SNESAddOptionsChecker(PetscErrorCode (*)(SNES));
72 
73 PETSC_EXTERN PetscErrorCode SNESSetUpdate(SNES, PetscErrorCode (*)(SNES, PetscInt));
74 
75 PETSC_EXTERN PetscErrorCode SNESRegisterAll(void);
76 
77 PETSC_EXTERN PetscErrorCode SNESRegister(const char[],PetscErrorCode (*)(SNES));
78 
79 PETSC_EXTERN PetscErrorCode SNESGetKSP(SNES,KSP*);
80 PETSC_EXTERN PetscErrorCode SNESSetKSP(SNES,KSP);
81 PETSC_EXTERN PetscErrorCode SNESGetSolution(SNES,Vec*);
82 PETSC_EXTERN PetscErrorCode SNESGetSolutionUpdate(SNES,Vec*);
83 PETSC_EXTERN PetscErrorCode SNESGetRhs(SNES,Vec*);
84 PETSC_EXTERN PetscErrorCode SNESView(SNES,PetscViewer);
85 PETSC_EXTERN PetscErrorCode SNESLoad(SNES,PetscViewer);
86 
87 #define SNES_FILE_CLASSID 1211224
88 
89 PETSC_EXTERN PetscErrorCode SNESSetOptionsPrefix(SNES,const char[]);
90 PETSC_EXTERN PetscErrorCode SNESAppendOptionsPrefix(SNES,const char[]);
91 PETSC_EXTERN PetscErrorCode SNESGetOptionsPrefix(SNES,const char*[]);
92 PETSC_EXTERN PetscErrorCode SNESSetFromOptions(SNES);
93 
94 PETSC_EXTERN PetscErrorCode MatCreateSNESMF(SNES,Mat*);
95 PETSC_EXTERN PetscErrorCode MatMFFDComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
96 
97 PETSC_EXTERN PetscErrorCode MatDAADSetSNES(Mat,SNES);
98 
99 PETSC_EXTERN PetscErrorCode SNESGetType(SNES,SNESType*);
100 PETSC_EXTERN PetscErrorCode SNESMonitorDefault(SNES,PetscInt,PetscReal,void *);
101 PETSC_EXTERN PetscErrorCode SNESMonitorRange(SNES,PetscInt,PetscReal,void *);
102 PETSC_EXTERN PetscErrorCode SNESMonitorRatio(SNES,PetscInt,PetscReal,void *);
103 PETSC_EXTERN PetscErrorCode SNESMonitorSetRatio(SNES,PetscViewer);
104 PETSC_EXTERN PetscErrorCode SNESMonitorSolution(SNES,PetscInt,PetscReal,void *);
105 PETSC_EXTERN PetscErrorCode SNESMonitorResidual(SNES,PetscInt,PetscReal,void *);
106 PETSC_EXTERN PetscErrorCode SNESMonitorSolutionUpdate(SNES,PetscInt,PetscReal,void *);
107 PETSC_EXTERN PetscErrorCode SNESMonitorDefaultShort(SNES,PetscInt,PetscReal,void *);
108 PETSC_EXTERN PetscErrorCode SNESMonitorJacUpdateSpectrum(SNES,PetscInt,PetscReal,void *);
109 PETSC_EXTERN PetscErrorCode SNESSetTolerances(SNES,PetscReal,PetscReal,PetscReal,PetscInt,PetscInt);
110 PETSC_EXTERN PetscErrorCode SNESGetTolerances(SNES,PetscReal*,PetscReal*,PetscReal*,PetscInt*,PetscInt*);
111 PETSC_EXTERN PetscErrorCode SNESSetTrustRegionTolerance(SNES,PetscReal);
112 PETSC_EXTERN PetscErrorCode SNESGetFunctionNorm(SNES,PetscReal*);
113 PETSC_EXTERN PetscErrorCode SNESSetFunctionNorm(SNES,PetscReal);
114 PETSC_EXTERN PetscErrorCode SNESGetIterationNumber(SNES,PetscInt*);
115 PETSC_EXTERN PetscErrorCode SNESSetIterationNumber(SNES,PetscInt);
116 
117 PETSC_EXTERN PetscErrorCode SNESGetNonlinearStepFailures(SNES,PetscInt*);
118 PETSC_EXTERN PetscErrorCode SNESSetMaxNonlinearStepFailures(SNES,PetscInt);
119 PETSC_EXTERN PetscErrorCode SNESGetMaxNonlinearStepFailures(SNES,PetscInt*);
120 PETSC_EXTERN PetscErrorCode SNESGetNumberFunctionEvals(SNES,PetscInt*);
121 
122 PETSC_EXTERN PetscErrorCode SNESSetLagPreconditioner(SNES,PetscInt);
123 PETSC_EXTERN PetscErrorCode SNESGetLagPreconditioner(SNES,PetscInt*);
124 PETSC_EXTERN PetscErrorCode SNESSetLagJacobian(SNES,PetscInt);
125 PETSC_EXTERN PetscErrorCode SNESGetLagJacobian(SNES,PetscInt*);
126 PETSC_EXTERN PetscErrorCode SNESSetLagPreconditionerPersists(SNES,PetscBool);
127 PETSC_EXTERN PetscErrorCode SNESSetLagJacobianPersists(SNES,PetscBool);
128 PETSC_EXTERN PetscErrorCode SNESSetGridSequence(SNES,PetscInt);
129 
130 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveIterations(SNES,PetscInt*);
131 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveFailures(SNES,PetscInt*);
132 PETSC_EXTERN PetscErrorCode SNESSetMaxLinearSolveFailures(SNES,PetscInt);
133 PETSC_EXTERN PetscErrorCode SNESGetMaxLinearSolveFailures(SNES,PetscInt*);
134 PETSC_EXTERN PetscErrorCode SNESSetCountersReset(SNES,PetscBool);
135 
136 PETSC_EXTERN PetscErrorCode SNESKSPSetUseEW(SNES,PetscBool );
137 PETSC_EXTERN PetscErrorCode SNESKSPGetUseEW(SNES,PetscBool *);
138 PETSC_EXTERN PetscErrorCode SNESKSPSetParametersEW(SNES,PetscInt,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal);
139 PETSC_EXTERN PetscErrorCode SNESKSPGetParametersEW(SNES,PetscInt*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*);
140 
141 #include <petscdrawtypes.h>
142 PETSC_EXTERN PetscErrorCode SNESMonitorLGCreate(const char[],const char[],int,int,int,int,PetscDrawLG*);
143 PETSC_EXTERN PetscErrorCode SNESMonitorLGResidualNorm(SNES,PetscInt,PetscReal,void*);
144 PETSC_EXTERN PetscErrorCode SNESMonitorLGDestroy(PetscDrawLG*);
145 PETSC_EXTERN PetscErrorCode SNESMonitorLGRange(SNES,PetscInt,PetscReal,void*);
146 
147 PETSC_EXTERN PetscErrorCode SNESSetApplicationContext(SNES,void *);
148 PETSC_EXTERN PetscErrorCode SNESGetApplicationContext(SNES,void *);
149 PETSC_EXTERN PetscErrorCode SNESSetComputeApplicationContext(SNES,PetscErrorCode (*)(SNES,void**),PetscErrorCode (*)(void**));
150 
151 PETSC_EXTERN PetscErrorCode SNESPythonSetType(SNES,const char[]);
152 
153 PETSC_EXTERN PetscErrorCode SNESSetFunctionDomainError(SNES);
154 PETSC_EXTERN PetscErrorCode SNESGetFunctionDomainError(SNES, PetscBool *);
155 
156 /*E
157     SNESConvergedReason - reason a SNES method was said to
158          have converged or diverged
159 
160    Level: beginner
161 
162    The two most common reasons for divergence are
163 $   1) an incorrectly coded or computed Jacobian or
164 $   2) failure or lack of convergence in the linear system (in this case we recommend
165 $      testing with -pc_type lu to eliminate the linear solver as the cause of the problem).
166 
167    Diverged Reasons:
168 .    SNES_DIVERGED_LOCAL_MIN - this can only occur when using the line-search variant of SNES.
169        The line search wants to minimize Q(alpha) = 1/2 || F(x + alpha s) ||^2_2  this occurs
170        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
171        you get Q'(alpha) = -F(x)^T F'(x)^(-1)^T F'(x+alpha s)F(x+alpha s); when alpha = 0
172        Q'(0) = - ||F(x)||^2_2 which is always NEGATIVE if F'(x) is invertible. This means the Newton
173        direction is a descent direction and the line search should succeed if alpha is small enough.
174 
175        If F'(x) is NOT invertible AND F'(x)^T F(x) = 0 then Q'(0) = 0 and the Newton direction
176        is NOT a descent direction so the line search will fail. All one can do at this point
177        is change the initial guess and try again.
178 
179        An alternative explanation: Newton's method can be regarded as replacing the function with
180        its linear approximation and minimizing the 2-norm of that. That is F(x+s) approx F(x) + F'(x)s
181        so we minimize || F(x) + F'(x) s ||^2_2; do this using Least Squares. If F'(x) is invertible then
182        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
183        exists a nontrival (that is F'(x)s != 0) solution to the equation and this direction is
184        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)
185        = - (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
186        and F'(x)^T F'(x) has no negative eigenvalues Q'(0) < 0 so s is a descent direction and the line
187        search should succeed for small enough alpha.
188 
189        Note that this RARELY happens in practice. Far more likely the linear system is not being solved
190        (well enough?) or the Jacobian is wrong.
191 
192    SNES_DIVERGED_MAX_IT means that the solver reached the maximum number of iterations without satisfying any
193    convergence criteria. SNES_CONVERGED_ITS means that SNESSkipConverged() was chosen as the convergence test;
194    thus the usual convergence criteria have not been checked and may or may not be satisfied.
195 
196    Developer Notes: this must match finclude/petscsnes.h
197 
198        The string versions of these are in SNESConvergedReason, if you change any value here you must
199      also adjust that array.
200 
201    Each reason has its own manual page.
202 
203 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPConvergedReason, SNESSetConvergenceTest()
204 E*/
205 typedef enum {/* converged */
206               SNES_CONVERGED_FNORM_ABS         =  2, /* ||F|| < atol */
207               SNES_CONVERGED_FNORM_RELATIVE    =  3, /* ||F|| < rtol*||F_initial|| */
208               SNES_CONVERGED_SNORM_RELATIVE    =  4, /* Newton computed step size small; || delta x || < stol || x ||*/
209               SNES_CONVERGED_ITS               =  5, /* maximum iterations reached */
210               SNES_CONVERGED_TR_DELTA          =  7,
211               /* diverged */
212               SNES_DIVERGED_FUNCTION_DOMAIN     = -1, /* the new x location passed the function is not in the domain of F */
213               SNES_DIVERGED_FUNCTION_COUNT      = -2,
214               SNES_DIVERGED_LINEAR_SOLVE        = -3, /* the linear solve failed */
215               SNES_DIVERGED_FNORM_NAN           = -4,
216               SNES_DIVERGED_MAX_IT              = -5,
217               SNES_DIVERGED_LINE_SEARCH         = -6, /* the line search failed */
218               SNES_DIVERGED_INNER               = -7, /* inner solve failed */
219               SNES_DIVERGED_LOCAL_MIN           = -8, /* || J^T b || is small, implies converged to local minimum of F() */
220               SNES_CONVERGED_ITERATING          =  0} SNESConvergedReason;
221 PETSC_EXTERN const char *const*SNESConvergedReasons;
222 
223 /*MC
224      SNES_CONVERGED_FNORM_ABS - 2-norm(F) <= abstol
225 
226    Level: beginner
227 
228 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
229 
230 M*/
231 
232 /*MC
233      SNES_CONVERGED_FNORM_RELATIVE - 2-norm(F) <= rtol*2-norm(F(x_0)) where x_0 is the initial guess
234 
235    Level: beginner
236 
237 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
238 
239 M*/
240 
241 /*MC
242      SNES_CONVERGED_SNORM_RELATIVE - The 2-norm of the last step <= stol * 2-norm(x) where x is the current
243           solution and stol is the 4th argument to SNESSetTolerances()
244 
245      Options Database Keys:
246       -snes_stol <stol> - the step tolerance
247 
248    Level: beginner
249 
250 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
251 
252 M*/
253 
254 /*MC
255      SNES_DIVERGED_FUNCTION_COUNT - The user provided function has been called more times then the final
256          argument to SNESSetTolerances()
257 
258    Level: beginner
259 
260 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
261 
262 M*/
263 
264 /*MC
265      SNES_DIVERGED_FNORM_NAN - the 2-norm of the current function evaluation is not-a-number (NaN), this
266       is usually caused by a division of 0 by 0.
267 
268    Level: beginner
269 
270 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
271 
272 M*/
273 
274 /*MC
275      SNES_DIVERGED_MAX_IT - SNESSolve() has reached the maximum number of iterations requested
276 
277    Level: beginner
278 
279 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
280 
281 M*/
282 
283 /*MC
284      SNES_DIVERGED_LINE_SEARCH - The line search has failed. This only occurs for a SNES solvers that use a line search
285 
286    Level: beginner
287 
288 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances(), SNESLineSearch
289 
290 M*/
291 
292 /*MC
293      SNES_DIVERGED_LOCAL_MIN - the algorithm seems to have stagnated at a local minimum that is not zero.
294         See the manual page for SNESConvergedReason for more details
295 
296    Level: beginner
297 
298 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
299 
300 M*/
301 
302 /*MC
303      SNES_CONERGED_ITERATING - this only occurs if SNESGetConvergedReason() is called during the SNESSolve()
304 
305    Level: beginner
306 
307 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
308 
309 M*/
310 
311 PETSC_EXTERN PetscErrorCode SNESSetConvergenceTest(SNES,PetscErrorCode (*)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*),void*,PetscErrorCode (*)(void*));
312 PETSC_EXTERN PetscErrorCode SNESConvergedDefault(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
313 PETSC_EXTERN PetscErrorCode SNESSkipConverged(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
314 PETSC_EXTERN PetscErrorCode SNESGetConvergedReason(SNES,SNESConvergedReason*);
315 
316 /* --------- Solving systems of nonlinear equations --------------- */
317 PETSC_EXTERN PetscErrorCode SNESSetFunction(SNES,Vec,PetscErrorCode (*SNESFunction)(SNES,Vec,Vec,void*),void*);
318 PETSC_EXTERN PetscErrorCode SNESGetFunction(SNES,Vec*,PetscErrorCode (**SNESFunction)(SNES,Vec,Vec,void*),void**);
319 PETSC_EXTERN PetscErrorCode SNESComputeFunction(SNES,Vec,Vec);
320 
321 PETSC_EXTERN PetscErrorCode SNESSetJacobian(SNES,Mat,Mat,PetscErrorCode (*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
322 PETSC_EXTERN PetscErrorCode SNESGetJacobian(SNES,Mat*,Mat*,PetscErrorCode (**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
323 PETSC_EXTERN PetscErrorCode SNESObjectiveComputeFunctionDefaultFD(SNES,Vec,Vec,void*);
324 PETSC_EXTERN PetscErrorCode SNESComputeJacobianDefault(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
325 PETSC_EXTERN PetscErrorCode SNESComputeJacobianDefaultColor(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
326 PETSC_EXTERN PetscErrorCode SNESSetComputeInitialGuess(SNES,PetscErrorCode (*)(SNES,Vec,void*),void*);
327 PETSC_EXTERN PetscErrorCode SNESSetPicard(SNES,Vec,PetscErrorCode (*SNESFunction)(SNES,Vec,Vec,void*),Mat,Mat,PetscErrorCode (*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
328 PETSC_EXTERN PetscErrorCode SNESGetPicard(SNES,Vec*,PetscErrorCode (**SNESFunction)(SNES,Vec,Vec,void*),Mat*,Mat*,PetscErrorCode (**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
329 PETSC_EXTERN PetscErrorCode SNESSetInitialFunction(SNES,Vec);
330 
331 PETSC_EXTERN PetscErrorCode SNESSetObjective(SNES,PetscErrorCode (*SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void*);
332 PETSC_EXTERN PetscErrorCode SNESGetObjective(SNES,PetscErrorCode (**SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void**);
333 PETSC_EXTERN PetscErrorCode SNESComputeObjective(SNES,Vec,PetscReal *);
334 
335 /*E
336     SNESNormSchedule - Frequency with which the norm is computed
337 
338    Level: advanced
339 
340    Support for these is highly dependent on the solver.
341 
342    Notes:
343    This is primarily used to turn off extra norm and function computation
344    when the solvers are composed.
345 
346 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPSetNormType(),
347           KSPSetConvergenceTest(), KSPSetPCSide()
348 E*/
349 
350 typedef enum {SNES_NORM_DEFAULT            = -1,
351               SNES_NORM_NONE               =  0,
352               SNES_NORM_ALWAYS             =  1,
353               SNES_NORM_INITIAL_ONLY       =  2,
354               SNES_NORM_FINAL_ONLY         =  3,
355               SNES_NORM_INITIAL_FINAL_ONLY =  4} SNESNormSchedule;
356 PETSC_EXTERN const char *const*const SNESNormSchedules;
357 /*MC
358     SNES_NORM_NONE - Don't compute function and its L2 norm.
359 
360    Level: advanced
361 
362     Notes:
363     This is most useful for stationary solvers with a fixed number of iterations used as smoothers.
364 
365 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_DEFAULT
366 M*/
367 
368 /*MC
369     SNES_NORM_ALWAYS - Compute the function and its L2 norm at each iteration.
370 
371    Level: advanced
372 
373     Notes:
374     Most solvers will use this no matter what norm type is passed to them.
375 
376 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_NONE
377 M*/
378 
379 /*MC
380     SNES_NORM_INITIAL_ONLY - Compute the function and its L2 at iteration 0, but do not update it.
381 
382    Level: advanced
383 
384    Notes:
385    This method is useful in composed methods, when a true solution might actually be found before SNESSolve() is called.
386    This option enables the solve to abort on the zeroth iteration if this is the case.
387 
388    For solvers that require the computation of the L2 norm of the function as part of the method, this merely cancels
389    the norm computation at the last iteration (if possible).
390 
391 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_FINAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
392 M*/
393 
394 /*MC
395     SNES_NORM_FINAL_ONLY - Compute the function and its L2 norm on only the final iteration.
396 
397    Level: advanced
398 
399    Notes:
400    For solvers that require the computation of the L2 norm of the function as part of the method, behaves
401    exactly as SNES_NORM_DEFAULT.  This method is useful when the function is gotten after SNESSolve and
402    used in subsequent computation for methods that do not need the norm computed during the rest of the
403    solution procedure.
404 
405 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_INITIAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
406 M*/
407 
408 /*MC
409     SNES_NORM_INITIAL_FINAL_ONLY - Compute the function and its L2 norm on only the initial and final iterations.
410 
411    Level: advanced
412 
413    Notes:
414    This method combines the benefits of SNES_NORM_INITIAL_ONLY and SNES_NORM_FINAL_ONLY.
415 
416 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_SNES_NORM_INITIAL_ONLY, SNES_NORM_FINAL_ONLY
417 M*/
418 
419 
420 PETSC_EXTERN PetscErrorCode SNESSetNormSchedule(SNES,SNESNormSchedule);
421 PETSC_EXTERN PetscErrorCode SNESGetNormSchedule(SNES,SNESNormSchedule*);
422 
423 /*E
424     SNESFunctionType - Type of function computed
425 
426    Level: advanced
427 
428    Support for these is highly dependent on the solver.
429 
430 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPSetNormType(),
431           KSPSetConvergenceTest(), KSPSetPCSide()
432 E*/
433 typedef enum {SNES_FUNCTION_DEFAULT          = -1,
434               SNES_FUNCTION_UNPRECONDITIONED =  0,
435               SNES_FUNCTION_PRECONDITIONED   =  1} SNESFunctionType;
436 PETSC_EXTERN const char *const*const SNESFunctionTypes;
437 
438 PETSC_EXTERN PetscErrorCode SNESSetFunctionType(SNES,SNESFunctionType);
439 PETSC_EXTERN PetscErrorCode SNESGetFunctionType(SNES,SNESFunctionType*);
440 
441 PETSC_EXTERN PetscErrorCode SNESSetGS(SNES,PetscErrorCode (*SNESGSFunction)(SNES,Vec,Vec,void*),void*);
442 PETSC_EXTERN PetscErrorCode SNESGetGS(SNES,PetscErrorCode (**SNESGSFunction)(SNES,Vec,Vec,void*),void**);
443 PETSC_EXTERN PetscErrorCode SNESSetUseGS(SNES,PetscBool);
444 PETSC_EXTERN PetscErrorCode SNESGetUseGS(SNES,PetscBool *);
445 PETSC_EXTERN PetscErrorCode SNESComputeGS(SNES,Vec,Vec);
446 
447 PETSC_EXTERN PetscErrorCode SNESGSSetSweeps(SNES,PetscInt);
448 PETSC_EXTERN PetscErrorCode SNESGSGetSweeps(SNES,PetscInt *);
449 PETSC_EXTERN PetscErrorCode SNESGSSetTolerances(SNES,PetscReal,PetscReal,PetscReal,PetscInt);
450 PETSC_EXTERN PetscErrorCode SNESGSGetTolerances(SNES,PetscReal*,PetscReal*,PetscReal*,PetscInt*);
451 
452 PETSC_EXTERN PetscErrorCode SNESUpdateCheckJacobian(SNES,PetscInt);
453 
454 PETSC_EXTERN PetscErrorCode SNESShellGetContext(SNES,void**);
455 PETSC_EXTERN PetscErrorCode SNESShellSetContext(SNES,void*);
456 PETSC_EXTERN PetscErrorCode SNESShellSetSolve(SNES,PetscErrorCode (*)(SNES,Vec));
457 
458 /* --------- Routines specifically for line search methods --------------- */
459 
460 typedef struct _p_LineSearch* SNESLineSearch;
461 
462 /*S
463      SNESLineSearch - Abstract PETSc object that manages line-search operations
464 
465    Level: beginner
466 
467   Concepts: nonlinear solvers, line search
468 
469 .seealso:  SNESLineSearchCreate(), SNESLineSearchSetType(), SNES
470 S*/
471 
472 /*J
473     SNESLineSearchType - String with the name of a PETSc line search method
474 
475    Level: beginner
476 
477 .seealso: SNESLineSearchSetType(), SNES
478 J*/
479 
480 typedef const char* SNESLineSearchType;
481 #define SNESLINESEARCHBT                 "bt"
482 #define SNESLINESEARCHBASIC              "basic"
483 #define SNESLINESEARCHL2                 "l2"
484 #define SNESLINESEARCHCP                 "cp"
485 #define SNESLINESEARCHSHELL              "shell"
486 
487 PETSC_EXTERN PetscBool         SNESRegisterAllCalled;
488 PETSC_EXTERN PetscFunctionList SNESList;
489 PETSC_EXTERN PetscClassId      SNESLINESEARCH_CLASSID;
490 PETSC_EXTERN PetscBool         SNESLineSearchRegisterAllCalled;
491 PETSC_EXTERN PetscFunctionList SNESLineSearchList;
492 PETSC_EXTERN PetscLogEvent     SNESLineSearch_Apply;
493 
494 #define SNES_LINESEARCH_ORDER_LINEAR    1
495 #define SNES_LINESEARCH_ORDER_QUADRATIC 2
496 #define SNES_LINESEARCH_ORDER_CUBIC     3
497 
498 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVIProjectFunc)(SNES,Vec);
499 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVINormFunc)(SNES,Vec,Vec,PetscReal *);
500 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchApplyFunc)(SNESLineSearch);
501 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchUserFunc)(SNESLineSearch, void *);
502 
503 PETSC_EXTERN PetscErrorCode SNESLineSearchCreate(MPI_Comm, SNESLineSearch*);
504 PETSC_EXTERN PetscErrorCode SNESLineSearchReset(SNESLineSearch);
505 PETSC_EXTERN PetscErrorCode SNESLineSearchView(SNESLineSearch,PetscViewer);
506 PETSC_EXTERN PetscErrorCode SNESLineSearchDestroy(SNESLineSearch *);
507 PETSC_EXTERN PetscErrorCode SNESLineSearchSetType(SNESLineSearch, SNESLineSearchType);
508 PETSC_EXTERN PetscErrorCode SNESLineSearchSetFromOptions(SNESLineSearch);
509 PETSC_EXTERN PetscErrorCode SNESLineSearchSetFunction(SNESLineSearch,PetscErrorCode (*)(SNES,Vec,Vec));
510 PETSC_EXTERN PetscErrorCode SNESLineSearchSetUp(SNESLineSearch);
511 PETSC_EXTERN PetscErrorCode SNESLineSearchApply(SNESLineSearch, Vec, Vec, PetscReal *, Vec);
512 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheck(SNESLineSearch,Vec,Vec,PetscBool *);
513 PETSC_EXTERN PetscErrorCode SNESLineSearchPostCheck(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *);
514 PETSC_EXTERN PetscErrorCode SNESLineSearchSetWorkVecs(SNESLineSearch, PetscInt);
515 
516 /* set the functions for precheck and postcheck */
517 
518 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPreCheck(SNESLineSearch, PetscErrorCode (*SNESLineSearchPreCheckFunction)(SNESLineSearch,Vec,Vec,PetscBool*,void*), void *ctx);
519 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPostCheck(SNESLineSearch, PetscErrorCode (*SNESLineSearchPostCheckFunction)(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *,void*), void *ctx);
520 
521 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPreCheck(SNESLineSearch, PetscErrorCode (**SNESLineSearchPreCheckFunction)(SNESLineSearch,Vec,Vec,PetscBool*,void*), void **ctx);
522 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPostCheck(SNESLineSearch, PetscErrorCode (**SNESLineSearchPostCheckFunction)(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *,void*), void **ctx);
523 
524 /* set the functions for VI-specific line search operations */
525 
526 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc, SNESLineSearchVINormFunc);
527 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc*, SNESLineSearchVINormFunc*);
528 
529 /* pointers to the associated SNES in order to be able to get the function evaluation out */
530 PETSC_EXTERN PetscErrorCode SNESLineSearchSetSNES(SNESLineSearch,SNES);
531 PETSC_EXTERN PetscErrorCode SNESLineSearchGetSNES(SNESLineSearch,SNES*);
532 
533 /* set and get the parameters and vectors */
534 PETSC_EXTERN PetscErrorCode SNESLineSearchGetTolerances(SNESLineSearch,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscInt*);
535 PETSC_EXTERN PetscErrorCode SNESLineSearchSetTolerances(SNESLineSearch,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscInt);
536 
537 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheckPicard(SNESLineSearch,Vec,Vec,PetscBool*,void*);
538 
539 PETSC_EXTERN PetscErrorCode SNESLineSearchGetLambda(SNESLineSearch,PetscReal*);
540 PETSC_EXTERN PetscErrorCode SNESLineSearchSetLambda(SNESLineSearch,PetscReal);
541 
542 PETSC_EXTERN PetscErrorCode SNESLineSearchGetDamping(SNESLineSearch,PetscReal*);
543 PETSC_EXTERN PetscErrorCode SNESLineSearchSetDamping(SNESLineSearch,PetscReal);
544 
545 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOrder(SNESLineSearch,PetscInt *order);
546 PETSC_EXTERN PetscErrorCode SNESLineSearchSetOrder(SNESLineSearch,PetscInt order);
547 
548 PETSC_EXTERN PetscErrorCode SNESLineSearchGetSuccess(SNESLineSearch, PetscBool*);
549 PETSC_EXTERN PetscErrorCode SNESLineSearchSetSuccess(SNESLineSearch, PetscBool);
550 
551 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVecs(SNESLineSearch,Vec*,Vec*,Vec*,Vec*,Vec*);
552 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVecs(SNESLineSearch,Vec,Vec,Vec,Vec,Vec);
553 
554 PETSC_EXTERN PetscErrorCode SNESLineSearchGetNorms(SNESLineSearch, PetscReal *, PetscReal *, PetscReal *);
555 PETSC_EXTERN PetscErrorCode SNESLineSearchSetNorms(SNESLineSearch, PetscReal, PetscReal, PetscReal);
556 PETSC_EXTERN PetscErrorCode SNESLineSearchComputeNorms(SNESLineSearch);
557 PETSC_EXTERN PetscErrorCode SNESLineSearchSetComputeNorms(SNESLineSearch, PetscBool);
558 
559 PETSC_EXTERN PetscErrorCode SNESLineSearchSetMonitor(SNESLineSearch, PetscBool);
560 PETSC_EXTERN PetscErrorCode SNESLineSearchGetMonitor(SNESLineSearch, PetscViewer*);
561 
562 PETSC_EXTERN PetscErrorCode SNESLineSearchAppendOptionsPrefix(SNESLineSearch, const char prefix[]);
563 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOptionsPrefix(SNESLineSearch, const char *prefix[]);
564 
565 
566 /* Shell interface functions */
567 PETSC_EXTERN PetscErrorCode SNESLineSearchShellSetUserFunc(SNESLineSearch,SNESLineSearchUserFunc,void*);
568 PETSC_EXTERN PetscErrorCode SNESLineSearchShellGetUserFunc(SNESLineSearch,SNESLineSearchUserFunc*,void**);
569 
570 /* BT interface functions */
571 PETSC_EXTERN PetscErrorCode SNESLineSearchBTSetAlpha(SNESLineSearch, PetscReal);
572 PETSC_EXTERN PetscErrorCode SNESLineSearchBTGetAlpha(SNESLineSearch, PetscReal*);
573 
574 /*register line search types */
575 PETSC_EXTERN PetscErrorCode SNESLineSearchRegister(const char[],PetscErrorCode(*)(SNESLineSearch));
576 PETSC_EXTERN PetscErrorCode SNESLineSearchRegisterAll(void);
577 
578 /* Routines for VI solver */
579 PETSC_EXTERN PetscErrorCode SNESVISetVariableBounds(SNES,Vec,Vec);
580 PETSC_EXTERN PetscErrorCode SNESVISetComputeVariableBounds(SNES, PetscErrorCode (*)(SNES,Vec,Vec));
581 PETSC_EXTERN PetscErrorCode SNESVIGetInactiveSet(SNES,IS*);
582 PETSC_EXTERN PetscErrorCode SNESVIGetActiveSetIS(SNES,Vec,Vec,IS*);
583 PETSC_EXTERN PetscErrorCode SNESVIComputeInactiveSetFnorm(SNES,Vec,Vec,PetscReal*);
584 PETSC_EXTERN PetscErrorCode SNESVISetRedundancyCheck(SNES,PetscErrorCode(*)(SNES,IS,IS*,void*),void*);
585 #define SNES_VI_INF   1.0e20
586 #define SNES_VI_NINF -1.0e20
587 
588 PETSC_EXTERN PetscErrorCode SNESTestLocalMin(SNES);
589 
590 /* Should this routine be private? */
591 PETSC_EXTERN PetscErrorCode SNESComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*);
592 
593 PETSC_EXTERN PetscErrorCode SNESSetDM(SNES,DM);
594 PETSC_EXTERN PetscErrorCode SNESGetDM(SNES,DM*);
595 PETSC_EXTERN PetscErrorCode SNESSetPC(SNES,SNES);
596 PETSC_EXTERN PetscErrorCode SNESGetPC(SNES,SNES*);
597 PETSC_EXTERN PetscErrorCode SNESApplyPC(SNES,Vec,Vec,PetscReal*,Vec);
598 PETSC_EXTERN PetscErrorCode SNESGetPCFunction(SNES,Vec,PetscReal*);
599 PETSC_EXTERN PetscErrorCode SNESComputeFunctionDefaultPC(SNES,Vec,Vec);
600 PETSC_EXTERN PetscErrorCode SNESSetPCSide(SNES,PCSide);
601 PETSC_EXTERN PetscErrorCode SNESGetPCSide(SNES,PCSide*);
602 PETSC_EXTERN PetscErrorCode SNESSetLineSearch(SNES,SNESLineSearch);
603 PETSC_EXTERN PetscErrorCode SNESGetLineSearch(SNES,SNESLineSearch*);
604 PETSC_EXTERN PetscErrorCode SNESRestrictHookAdd(SNES,PetscErrorCode (*)(SNES,SNES,void*),void*);
605 PETSC_EXTERN PetscErrorCode SNESRestrictHooksRun(SNES,SNES);
606 
607 PETSC_DEPRECATED("Use SNESGetLineSearch()") PETSC_STATIC_INLINE PetscErrorCode SNESGetSNESLineSearch(SNES snes,SNESLineSearch *ls) {return SNESGetLineSearch(snes,ls);}
608 PETSC_DEPRECATED("Use SNESSetLineSearch()") PETSC_STATIC_INLINE PetscErrorCode SNESSetSNESLineSearch(SNES snes,SNESLineSearch ls) {return SNESSetLineSearch(snes,ls);}
609 
610 PETSC_EXTERN PetscErrorCode SNESSetUpMatrices(SNES);
611 PETSC_EXTERN PetscErrorCode DMSNESSetFunction(DM,PetscErrorCode(*SNESFunction)(SNES,Vec,Vec,void*),void*);
612 PETSC_EXTERN PetscErrorCode DMSNESGetFunction(DM,PetscErrorCode(**SNESSetFunction)(SNES,Vec,Vec,void*),void**);
613 PETSC_EXTERN PetscErrorCode DMSNESSetGS(DM,PetscErrorCode(*SNESGSFunction)(SNES,Vec,Vec,void*),void*);
614 PETSC_EXTERN PetscErrorCode DMSNESGetGS(DM,PetscErrorCode(**SNESGSFunction)(SNES,Vec,Vec,void*),void**);
615 PETSC_EXTERN PetscErrorCode DMSNESSetJacobian(DM,PetscErrorCode(*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
616 PETSC_EXTERN PetscErrorCode DMSNESGetJacobian(DM,PetscErrorCode(**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
617 PETSC_EXTERN PetscErrorCode DMSNESSetPicard(DM,PetscErrorCode(*SNESFunction)(SNES,Vec,Vec,void*),PetscErrorCode(*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
618 PETSC_EXTERN PetscErrorCode DMSNESGetPicard(DM,PetscErrorCode(**SNESFunction)(SNES,Vec,Vec,void*),PetscErrorCode(**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
619 PETSC_EXTERN PetscErrorCode DMSNESSetObjective(DM,PetscErrorCode (*SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void*);
620 PETSC_EXTERN PetscErrorCode DMSNESGetObjective(DM,PetscErrorCode (**SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void**);
621 
622 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESFunction)(DMDALocalInfo*,void*,void*,void*);
623 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESJacobian)(DMDALocalInfo*,void*,Mat,Mat,MatStructure*,void*);
624 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESObjective)(DMDALocalInfo*,void*,PetscReal*,void*);
625 
626 PETSC_EXTERN PetscErrorCode DMDASNESSetFunctionLocal(DM,InsertMode,DMDASNESFunction,void*);
627 PETSC_EXTERN PetscErrorCode DMDASNESSetJacobianLocal(DM,DMDASNESJacobian,void*);
628 PETSC_EXTERN PetscErrorCode DMDASNESSetObjectiveLocal(DM,DMDASNESObjective,void*);
629 PETSC_EXTERN PetscErrorCode DMDASNESSetPicardLocal(DM,InsertMode,PetscErrorCode (*)(DMDALocalInfo*,void*,void*,void*),PetscErrorCode (*)(DMDALocalInfo*,void*,Mat,Mat,MatStructure*,void*),void*);
630 
631 PETSC_EXTERN PetscErrorCode DMSNESSetFunctionLocal(DM,PetscErrorCode (*)(DM,Vec,Vec,void*),void*);
632 PETSC_EXTERN PetscErrorCode DMSNESSetJacobianLocal(DM,PetscErrorCode (*)(DM,Vec,Mat,Mat,MatStructure*,void*),void*);
633 
634 /* Routines for Multiblock solver */
635 PETSC_EXTERN PetscErrorCode SNESMultiblockSetFields(SNES, const char [], PetscInt, const PetscInt *);
636 PETSC_EXTERN PetscErrorCode SNESMultiblockSetIS(SNES, const char [], IS);
637 PETSC_EXTERN PetscErrorCode SNESMultiblockSetBlockSize(SNES, PetscInt);
638 PETSC_EXTERN PetscErrorCode SNESMultiblockSetType(SNES, PCCompositeType);
639 
640 /*J
641     SNESMSType - String with the name of a PETSc SNESMS method.
642 
643    Level: intermediate
644 
645 .seealso: SNESMSSetType(), SNES
646 J*/
647 typedef const char* SNESMSType;
648 #define SNESMSM62       "m62"
649 #define SNESMSEULER     "euler"
650 #define SNESMSJAMESON83 "jameson83"
651 #define SNESMSVLTP21    "vltp21"
652 #define SNESMSVLTP31    "vltp31"
653 #define SNESMSVLTP41    "vltp41"
654 #define SNESMSVLTP51    "vltp51"
655 #define SNESMSVLTP61    "vltp61"
656 
657 PETSC_EXTERN PetscErrorCode SNESMSRegister(SNESMSType,PetscInt,PetscInt,PetscReal,const PetscReal[],const PetscReal[],const PetscReal[]);
658 PETSC_EXTERN PetscErrorCode SNESMSSetType(SNES,SNESMSType);
659 PETSC_EXTERN PetscErrorCode SNESMSFinalizePackage(void);
660 PETSC_EXTERN PetscErrorCode SNESMSInitializePackage(void);
661 PETSC_EXTERN PetscErrorCode SNESMSRegisterDestroy(void);
662 PETSC_EXTERN PetscErrorCode SNESMSRegisterAll(void);
663 
664 /* routines for NGMRES solver */
665 
666 typedef enum {
667   SNES_NGMRES_RESTART_NONE       = 0,
668   SNES_NGMRES_RESTART_PERIODIC   = 1,
669   SNES_NGMRES_RESTART_DIFFERENCE = 2} SNESNGMRESRestartType;
670 PETSC_EXTERN const char *const SNESNGMRESRestartTypes[];
671 
672 typedef enum {
673   SNES_NGMRES_SELECT_NONE       = 0,
674   SNES_NGMRES_SELECT_DIFFERENCE = 1,
675   SNES_NGMRES_SELECT_LINESEARCH = 2} SNESNGMRESSelectType;
676 PETSC_EXTERN const char *const SNESNGMRESSelectTypes[];
677 
678 PETSC_EXTERN PetscErrorCode SNESNGMRESSetRestartType(SNES, SNESNGMRESRestartType);
679 PETSC_EXTERN PetscErrorCode SNESNGMRESSetSelectType(SNES, SNESNGMRESSelectType);
680 
681 /* routines for NCG solver */
682 
683 typedef enum {
684   SNES_NCG_FR    = 0,
685   SNES_NCG_PRP   = 1,
686   SNES_NCG_HS    = 2,
687   SNES_NCG_DY    = 3,
688   SNES_NCG_CD    = 4} SNESNCGType;
689 PETSC_EXTERN const char *const SNESNCGTypes[];
690 
691 PETSC_EXTERN PetscErrorCode SNESNCGSetType(SNES, SNESNCGType);
692 
693 typedef enum {SNES_QN_SCALE_NONE       = 0,
694               SNES_QN_SCALE_SHANNO     = 1,
695               SNES_QN_SCALE_LINESEARCH = 2,
696               SNES_QN_SCALE_JACOBIAN   = 3} SNESQNScaleType;
697 PETSC_EXTERN const char *const SNESQNScaleTypes[];
698 typedef enum {SNES_QN_RESTART_NONE     = 0,
699               SNES_QN_RESTART_POWELL   = 1,
700               SNES_QN_RESTART_PERIODIC = 2} SNESQNRestartType;
701 PETSC_EXTERN const char *const SNESQNRestartTypes[];
702 
703 PETSC_EXTERN PetscErrorCode SNESQNSetScaleType(SNES, SNESQNScaleType);
704 PETSC_EXTERN PetscErrorCode SNESQNSetRestartType(SNES, SNESQNRestartType);
705 
706 PETSC_EXTERN PetscErrorCode SNESNASMGetSubdomains(SNES,PetscInt*,SNES**,VecScatter**,VecScatter**,VecScatter**);
707 PETSC_EXTERN PetscErrorCode SNESNASMSetSubdomains(SNES,PetscInt,SNES*,VecScatter*,VecScatter*,VecScatter*);
708 PETSC_EXTERN PetscErrorCode SNESNASMSetDamping(SNES,PetscReal);
709 PETSC_EXTERN PetscErrorCode SNESNASMGetDamping(SNES,PetscReal*);
710 PETSC_EXTERN PetscErrorCode SNESNASMGetSubdomainVecs(SNES,PetscInt*,Vec**,Vec**,Vec**,Vec**);
711 PETSC_EXTERN PetscErrorCode SNESNASMSetComputeFinalJacobian(SNES,PetscBool);
712 
713 typedef enum {SNES_COMPOSITE_ADDITIVE,SNES_COMPOSITE_MULTIPLICATIVE,SNES_COMPOSITE_ADDITIVEOPTIMAL} SNESCompositeType;
714 PETSC_EXTERN const char *const SNESCompositeTypes[];
715 
716 PETSC_EXTERN PetscErrorCode SNESCompositeSetType(SNES,SNESCompositeType);
717 PETSC_EXTERN PetscErrorCode SNESCompositeAddSNES(SNES,SNESType);
718 PETSC_EXTERN PetscErrorCode SNESCompositeGetSNES(SNES,PetscInt,SNES *);
719 PETSC_EXTERN PetscErrorCode SNESCompositeSetDamping(SNES,PetscInt,PetscReal);
720 
721 #endif
722