xref: /petsc/include/petscsnes.h (revision 6c2ad439436f13bf1feaaeb1f0f1d84516847a4e) 
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
18 S*/
19 typedef struct _p_SNES* SNES;
20 
21 /*J
22     SNESType - String with the name of a PETSc SNES method or the creation function
23        with an optional dynamic library name, for example
24        http://www.mcs.anl.gov/petsc/lib.a:mysnescreate()
25 
26    Level: beginner
27 
28 .seealso: SNESSetType(), SNES
29 J*/
30 typedef const char* SNESType;
31 #define SNESNEWTONLS     "newtonls"
32 #define SNESNEWTONTR     "newtontr"
33 #define SNESPYTHON       "python"
34 #define SNESTEST         "test"
35 #define SNESNRICHARDSON  "nrichardson"
36 #define SNESKSPONLY      "ksponly"
37 #define SNESVINEWTONRSLS "vinewtonrsls"
38 #define SNESVINEWTONSSLS "vinewtonssls"
39 #define SNESNGMRES       "ngmres"
40 #define SNESQN           "qn"
41 #define SNESSHELL        "shell"
42 #define SNESGS           "gs"
43 #define SNESNCG          "ncg"
44 #define SNESFAS          "fas"
45 #define SNESMS           "ms"
46 #define SNESNASM         "nasm"
47 #define SNESANDERSON     "anderson"
48 #define SNESASPIN        "aspin"
49 
50 /* Logging support */
51 PETSC_EXTERN PetscClassId SNES_CLASSID;
52 PETSC_EXTERN PetscClassId DMSNES_CLASSID;
53 
54 PETSC_EXTERN PetscErrorCode SNESInitializePackage(void);
55 
56 PETSC_EXTERN PetscErrorCode SNESCreate(MPI_Comm,SNES*);
57 PETSC_EXTERN PetscErrorCode SNESReset(SNES);
58 PETSC_EXTERN PetscErrorCode SNESDestroy(SNES*);
59 PETSC_EXTERN PetscErrorCode SNESSetType(SNES,SNESType);
60 PETSC_EXTERN PetscErrorCode SNESMonitor(SNES,PetscInt,PetscReal);
61 PETSC_EXTERN PetscErrorCode SNESMonitorSet(SNES,PetscErrorCode(*)(SNES,PetscInt,PetscReal,void*),void *,PetscErrorCode (*)(void**));
62 PETSC_EXTERN PetscErrorCode SNESMonitorCancel(SNES);
63 PETSC_EXTERN PetscErrorCode SNESSetConvergenceHistory(SNES,PetscReal[],PetscInt[],PetscInt,PetscBool );
64 PETSC_EXTERN PetscErrorCode SNESGetConvergenceHistory(SNES,PetscReal*[],PetscInt *[],PetscInt *);
65 PETSC_EXTERN PetscErrorCode SNESSetUp(SNES);
66 PETSC_EXTERN PetscErrorCode SNESSolve(SNES,Vec,Vec);
67 PETSC_EXTERN PetscErrorCode SNESSetErrorIfNotConverged(SNES,PetscBool );
68 PETSC_EXTERN PetscErrorCode SNESGetErrorIfNotConverged(SNES,PetscBool  *);
69 
70 PETSC_EXTERN PetscErrorCode SNESSetWorkVecs(SNES,PetscInt);
71 
72 PETSC_EXTERN PetscErrorCode SNESAddOptionsChecker(PetscErrorCode (*)(SNES));
73 
74 PETSC_EXTERN PetscErrorCode SNESSetUpdate(SNES, PetscErrorCode (*)(SNES, PetscInt));
75 
76 PETSC_EXTERN PetscErrorCode SNESRegisterAll(void);
77 
78 PETSC_EXTERN PetscErrorCode SNESRegister(const char[],PetscErrorCode (*)(SNES));
79 
80 PETSC_EXTERN PetscErrorCode SNESGetKSP(SNES,KSP*);
81 PETSC_EXTERN PetscErrorCode SNESSetKSP(SNES,KSP);
82 PETSC_EXTERN PetscErrorCode SNESGetSolution(SNES,Vec*);
83 PETSC_EXTERN PetscErrorCode SNESGetSolutionUpdate(SNES,Vec*);
84 PETSC_EXTERN PetscErrorCode SNESGetRhs(SNES,Vec*);
85 PETSC_EXTERN PetscErrorCode SNESView(SNES,PetscViewer);
86 PETSC_EXTERN PetscErrorCode SNESLoad(SNES,PetscViewer);
87 
88 #define SNES_FILE_CLASSID 1211224
89 
90 PETSC_EXTERN PetscErrorCode SNESSetOptionsPrefix(SNES,const char[]);
91 PETSC_EXTERN PetscErrorCode SNESAppendOptionsPrefix(SNES,const char[]);
92 PETSC_EXTERN PetscErrorCode SNESGetOptionsPrefix(SNES,const char*[]);
93 PETSC_EXTERN PetscErrorCode SNESSetFromOptions(SNES);
94 
95 PETSC_EXTERN PetscErrorCode MatCreateSNESMF(SNES,Mat*);
96 PETSC_EXTERN PetscErrorCode MatMFFDComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
97 
98 PETSC_EXTERN PetscErrorCode MatDAADSetSNES(Mat,SNES);
99 
100 PETSC_EXTERN PetscErrorCode SNESGetType(SNES,SNESType*);
101 PETSC_EXTERN PetscErrorCode SNESMonitorDefault(SNES,PetscInt,PetscReal,void *);
102 PETSC_EXTERN PetscErrorCode SNESMonitorRange(SNES,PetscInt,PetscReal,void *);
103 PETSC_EXTERN PetscErrorCode SNESMonitorRatio(SNES,PetscInt,PetscReal,void *);
104 PETSC_EXTERN PetscErrorCode SNESMonitorSetRatio(SNES,PetscViewer);
105 PETSC_EXTERN PetscErrorCode SNESMonitorSolution(SNES,PetscInt,PetscReal,void *);
106 PETSC_EXTERN PetscErrorCode SNESMonitorResidual(SNES,PetscInt,PetscReal,void *);
107 PETSC_EXTERN PetscErrorCode SNESMonitorSolutionUpdate(SNES,PetscInt,PetscReal,void *);
108 PETSC_EXTERN PetscErrorCode SNESMonitorDefaultShort(SNES,PetscInt,PetscReal,void *);
109 PETSC_EXTERN PetscErrorCode SNESMonitorJacUpdateSpectrum(SNES,PetscInt,PetscReal,void *);
110 PETSC_EXTERN PetscErrorCode SNESSetTolerances(SNES,PetscReal,PetscReal,PetscReal,PetscInt,PetscInt);
111 PETSC_EXTERN PetscErrorCode SNESGetTolerances(SNES,PetscReal*,PetscReal*,PetscReal*,PetscInt*,PetscInt*);
112 PETSC_EXTERN PetscErrorCode SNESSetTrustRegionTolerance(SNES,PetscReal);
113 PETSC_EXTERN PetscErrorCode SNESGetFunctionNorm(SNES,PetscReal*);
114 PETSC_EXTERN PetscErrorCode SNESSetFunctionNorm(SNES,PetscReal);
115 PETSC_EXTERN PetscErrorCode SNESGetIterationNumber(SNES,PetscInt*);
116 PETSC_EXTERN PetscErrorCode SNESSetIterationNumber(SNES,PetscInt);
117 
118 PETSC_EXTERN PetscErrorCode SNESGetNonlinearStepFailures(SNES,PetscInt*);
119 PETSC_EXTERN PetscErrorCode SNESSetMaxNonlinearStepFailures(SNES,PetscInt);
120 PETSC_EXTERN PetscErrorCode SNESGetMaxNonlinearStepFailures(SNES,PetscInt*);
121 PETSC_EXTERN PetscErrorCode SNESGetNumberFunctionEvals(SNES,PetscInt*);
122 
123 PETSC_EXTERN PetscErrorCode SNESSetLagPreconditioner(SNES,PetscInt);
124 PETSC_EXTERN PetscErrorCode SNESGetLagPreconditioner(SNES,PetscInt*);
125 PETSC_EXTERN PetscErrorCode SNESSetLagJacobian(SNES,PetscInt);
126 PETSC_EXTERN PetscErrorCode SNESGetLagJacobian(SNES,PetscInt*);
127 PETSC_EXTERN PetscErrorCode SNESSetLagPreconditionerPersists(SNES,PetscBool);
128 PETSC_EXTERN PetscErrorCode SNESSetLagJacobianPersists(SNES,PetscBool);
129 PETSC_EXTERN PetscErrorCode SNESSetGridSequence(SNES,PetscInt);
130 
131 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveIterations(SNES,PetscInt*);
132 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveFailures(SNES,PetscInt*);
133 PETSC_EXTERN PetscErrorCode SNESSetMaxLinearSolveFailures(SNES,PetscInt);
134 PETSC_EXTERN PetscErrorCode SNESGetMaxLinearSolveFailures(SNES,PetscInt*);
135 PETSC_EXTERN PetscErrorCode SNESSetCountersReset(SNES,PetscBool);
136 
137 PETSC_EXTERN PetscErrorCode SNESKSPSetUseEW(SNES,PetscBool );
138 PETSC_EXTERN PetscErrorCode SNESKSPGetUseEW(SNES,PetscBool *);
139 PETSC_EXTERN PetscErrorCode SNESKSPSetParametersEW(SNES,PetscInt,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal);
140 PETSC_EXTERN PetscErrorCode SNESKSPGetParametersEW(SNES,PetscInt*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*);
141 
142 #include <petscdrawtypes.h>
143 PETSC_EXTERN PetscErrorCode SNESMonitorLGCreate(const char[],const char[],int,int,int,int,PetscDrawLG*);
144 PETSC_EXTERN PetscErrorCode SNESMonitorLGResidualNorm(SNES,PetscInt,PetscReal,void*);
145 PETSC_EXTERN PetscErrorCode SNESMonitorLGDestroy(PetscDrawLG*);
146 PETSC_EXTERN PetscErrorCode SNESMonitorLGRange(SNES,PetscInt,PetscReal,void*);
147 
148 PETSC_EXTERN PetscErrorCode SNESSetApplicationContext(SNES,void *);
149 PETSC_EXTERN PetscErrorCode SNESGetApplicationContext(SNES,void *);
150 PETSC_EXTERN PetscErrorCode SNESSetComputeApplicationContext(SNES,PetscErrorCode (*)(SNES,void**),PetscErrorCode (*)(void**));
151 
152 PETSC_EXTERN PetscErrorCode SNESPythonSetType(SNES,const char[]);
153 
154 PETSC_EXTERN PetscErrorCode SNESSetFunctionDomainError(SNES);
155 PETSC_EXTERN PetscErrorCode SNESGetFunctionDomainError(SNES, PetscBool *);
156 
157 /*E
158     SNESConvergedReason - reason a SNES method was said to
159          have converged or diverged
160 
161    Level: beginner
162 
163    The two most common reasons for divergence are
164 $   1) an incorrectly coded or computed Jacobian or
165 $   2) failure or lack of convergence in the linear system (in this case we recommend
166 $      testing with -pc_type lu to eliminate the linear solver as the cause of the problem).
167 
168    Diverged Reasons:
169 .    SNES_DIVERGED_LOCAL_MIN - this can only occur when using the line-search variant of SNES.
170        The line search wants to minimize Q(alpha) = 1/2 || F(x + alpha s) ||^2_2  this occurs
171        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
172        you get Q'(alpha) = -F(x)^T F'(x)^(-1)^T F'(x+alpha s)F(x+alpha s); when alpha = 0
173        Q'(0) = - ||F(x)||^2_2 which is always NEGATIVE if F'(x) is invertible. This means the Newton
174        direction is a descent direction and the line search should succeed if alpha is small enough.
175 
176        If F'(x) is NOT invertible AND F'(x)^T F(x) = 0 then Q'(0) = 0 and the Newton direction
177        is NOT a descent direction so the line search will fail. All one can do at this point
178        is change the initial guess and try again.
179 
180        An alternative explanation: Newton's method can be regarded as replacing the function with
181        its linear approximation and minimizing the 2-norm of that. That is F(x+s) approx F(x) + F'(x)s
182        so we minimize || F(x) + F'(x) s ||^2_2; do this using Least Squares. If F'(x) is invertible then
183        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
184        exists a nontrival (that is F'(x)s != 0) solution to the equation and this direction is
185        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)
186        = - (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
187        and F'(x)^T F'(x) has no negative eigenvalues Q'(0) < 0 so s is a descent direction and the line
188        search should succeed for small enough alpha.
189 
190        Note that this RARELY happens in practice. Far more likely the linear system is not being solved
191        (well enough?) or the Jacobian is wrong.
192 
193    SNES_DIVERGED_MAX_IT means that the solver reached the maximum number of iterations without satisfying any
194    convergence criteria. SNES_CONVERGED_ITS means that SNESSkipConverged() was chosen as the convergence test;
195    thus the usual convergence criteria have not been checked and may or may not be satisfied.
196 
197    Developer Notes: this must match finclude/petscsnes.h
198 
199        The string versions of these are in SNESConvergedReason, if you change any value here you must
200      also adjust that array.
201 
202    Each reason has its own manual page.
203 
204 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPConvergedReason, SNESSetConvergenceTest()
205 E*/
206 typedef enum {/* converged */
207               SNES_CONVERGED_FNORM_ABS         =  2, /* ||F|| < atol */
208               SNES_CONVERGED_FNORM_RELATIVE    =  3, /* ||F|| < rtol*||F_initial|| */
209               SNES_CONVERGED_SNORM_RELATIVE    =  4, /* Newton computed step size small; || delta x || < stol || x ||*/
210               SNES_CONVERGED_ITS               =  5, /* maximum iterations reached */
211               SNES_CONVERGED_TR_DELTA          =  7,
212               /* diverged */
213               SNES_DIVERGED_FUNCTION_DOMAIN     = -1, /* the new x location passed the function is not in the domain of F */
214               SNES_DIVERGED_FUNCTION_COUNT      = -2,
215               SNES_DIVERGED_LINEAR_SOLVE        = -3, /* the linear solve failed */
216               SNES_DIVERGED_FNORM_NAN           = -4,
217               SNES_DIVERGED_MAX_IT              = -5,
218               SNES_DIVERGED_LINE_SEARCH         = -6, /* the line search failed */
219               SNES_DIVERGED_INNER               = -7, /* inner solve failed */
220               SNES_DIVERGED_LOCAL_MIN           = -8, /* || J^T b || is small, implies converged to local minimum of F() */
221               SNES_CONVERGED_ITERATING          =  0} SNESConvergedReason;
222 PETSC_EXTERN const char *const*SNESConvergedReasons;
223 
224 /*MC
225      SNES_CONVERGED_FNORM_ABS - 2-norm(F) <= abstol
226 
227    Level: beginner
228 
229 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
230 
231 M*/
232 
233 /*MC
234      SNES_CONVERGED_FNORM_RELATIVE - 2-norm(F) <= rtol*2-norm(F(x_0)) where x_0 is the initial guess
235 
236    Level: beginner
237 
238 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
239 
240 M*/
241 
242 /*MC
243      SNES_CONVERGED_SNORM_RELATIVE - The 2-norm of the last step <= stol * 2-norm(x) where x is the current
244           solution and stol is the 4th argument to SNESSetTolerances()
245 
246      Options Database Keys:
247       -snes_stol <stol> - the step tolerance
248 
249    Level: beginner
250 
251 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
252 
253 M*/
254 
255 /*MC
256      SNES_DIVERGED_FUNCTION_COUNT - The user provided function has been called more times then the final
257          argument to SNESSetTolerances()
258 
259    Level: beginner
260 
261 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
262 
263 M*/
264 
265 /*MC
266      SNES_DIVERGED_FNORM_NAN - the 2-norm of the current function evaluation is not-a-number (NaN), this
267       is usually caused by a division of 0 by 0.
268 
269    Level: beginner
270 
271 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
272 
273 M*/
274 
275 /*MC
276      SNES_DIVERGED_MAX_IT - SNESSolve() has reached the maximum number of iterations requested
277 
278    Level: beginner
279 
280 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
281 
282 M*/
283 
284 /*MC
285      SNES_DIVERGED_LINE_SEARCH - The line search has failed. This only occurs for a SNES solvers that use a line search
286 
287    Level: beginner
288 
289 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances(), SNESLineSearch
290 
291 M*/
292 
293 /*MC
294      SNES_DIVERGED_LOCAL_MIN - the algorithm seems to have stagnated at a local minimum that is not zero.
295         See the manual page for SNESConvergedReason for more details
296 
297    Level: beginner
298 
299 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
300 
301 M*/
302 
303 /*MC
304      SNES_CONERGED_ITERATING - this only occurs if SNESGetConvergedReason() is called during the SNESSolve()
305 
306    Level: beginner
307 
308 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
309 
310 M*/
311 
312 PETSC_EXTERN PetscErrorCode SNESSetConvergenceTest(SNES,PetscErrorCode (*)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*),void*,PetscErrorCode (*)(void*));
313 PETSC_EXTERN PetscErrorCode SNESConvergedDefault(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
314 PETSC_EXTERN PetscErrorCode SNESSkipConverged(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
315 PETSC_EXTERN PetscErrorCode SNESGetConvergedReason(SNES,SNESConvergedReason*);
316 
317 PETSC_EXTERN PetscErrorCode SNESDMMeshComputeFunction(SNES,Vec,Vec,void*);
318 PETSC_EXTERN PetscErrorCode SNESDMMeshComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
319 
320 /* --------- Solving systems of nonlinear equations --------------- */
321 PETSC_EXTERN PetscErrorCode SNESSetFunction(SNES,Vec,PetscErrorCode (*SNESFunction)(SNES,Vec,Vec,void*),void*);
322 PETSC_EXTERN PetscErrorCode SNESGetFunction(SNES,Vec*,PetscErrorCode (**SNESFunction)(SNES,Vec,Vec,void*),void**);
323 PETSC_EXTERN PetscErrorCode SNESComputeFunction(SNES,Vec,Vec);
324 
325 PETSC_EXTERN PetscErrorCode SNESSetJacobian(SNES,Mat,Mat,PetscErrorCode (*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
326 PETSC_EXTERN PetscErrorCode SNESGetJacobian(SNES,Mat*,Mat*,PetscErrorCode (**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
327 PETSC_EXTERN PetscErrorCode SNESObjectiveComputeFunctionDefaultFD(SNES,Vec,Vec,void*);
328 PETSC_EXTERN PetscErrorCode SNESComputeJacobianDefault(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
329 PETSC_EXTERN PetscErrorCode SNESComputeJacobianDefaultColor(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
330 PETSC_EXTERN PetscErrorCode SNESSetComputeInitialGuess(SNES,PetscErrorCode (*)(SNES,Vec,void*),void*);
331 PETSC_EXTERN PetscErrorCode SNESSetPicard(SNES,Vec,PetscErrorCode (*SNESFunction)(SNES,Vec,Vec,void*),Mat,Mat,PetscErrorCode (*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
332 PETSC_EXTERN PetscErrorCode SNESGetPicard(SNES,Vec*,PetscErrorCode (**SNESFunction)(SNES,Vec,Vec,void*),Mat*,Mat*,PetscErrorCode (**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
333 PETSC_EXTERN PetscErrorCode SNESSetInitialFunction(SNES,Vec);
334 PETSC_EXTERN PetscErrorCode SNESSetInitialFunctionNorm(SNES,PetscReal);
335 
336 PETSC_EXTERN PetscErrorCode SNESSetObjective(SNES,PetscErrorCode (*SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void*);
337 PETSC_EXTERN PetscErrorCode SNESGetObjective(SNES,PetscErrorCode (**SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void**);
338 PETSC_EXTERN PetscErrorCode SNESComputeObjective(SNES,Vec,PetscReal *);
339 
340 /*E
341     SNESNormSchedule - Frequency with which the norm is computed
342 
343    Level: advanced
344 
345    Support for these is highly dependent on the solver.
346 
347    Notes:
348    This is primarily used to turn off extra norm and function computation
349    when the solvers are composed.
350 
351 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPSetNormType(),
352           KSPSetConvergenceTest(), KSPSetPCSide()
353 E*/
354 
355 typedef enum {SNES_NORM_DEFAULT            = -1,
356               SNES_NORM_NONE               =  0,
357               SNES_NORM_ALWAYS             =  1,
358               SNES_NORM_INITIAL_ONLY       =  2,
359               SNES_NORM_FINAL_ONLY         =  3,
360               SNES_NORM_INITIAL_FINAL_ONLY =  4} SNESNormSchedule;
361 PETSC_EXTERN const char *const*const SNESNormSchedules;
362 /*MC
363     SNES_NORM_NONE - Don't compute function and its L2 norm.
364 
365    Level: advanced
366 
367     Notes:
368     This is most useful for stationary solvers with a fixed number of iterations used as smoothers.
369 
370 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_DEFAULT
371 M*/
372 
373 /*MC
374     SNES_NORM_ALWAYS - Compute the function and its L2 norm at each iteration.
375 
376    Level: advanced
377 
378     Notes:
379     Most solvers will use this no matter what norm type is passed to them.
380 
381 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_NONE
382 M*/
383 
384 /*MC
385     SNES_NORM_INITIAL_ONLY - Compute the function and its L2 at iteration 0, but do not update it.
386 
387    Level: advanced
388 
389    Notes:
390    This method is useful in composed methods, when a true solution might actually be found before SNESSolve() is called.
391    This option enables the solve to abort on the zeroth iteration if this is the case.
392 
393    For solvers that require the computation of the L2 norm of the function as part of the method, this merely cancels
394    the norm computation at the last iteration (if possible).
395 
396 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_FINAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
397 M*/
398 
399 /*MC
400     SNES_NORM_FINAL_ONLY - Compute the function and its L2 norm on only the final iteration.
401 
402    Level: advanced
403 
404    Notes:
405    For solvers that require the computation of the L2 norm of the function as part of the method, behaves
406    exactly as SNES_NORM_DEFAULT.  This method is useful when the function is gotten after SNESSolve and
407    used in subsequent computation for methods that do not need the norm computed during the rest of the
408    solution procedure.
409 
410 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_INITIAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
411 M*/
412 
413 /*MC
414     SNES_NORM_INITIAL_FINAL_ONLY - Compute the function and its L2 norm on only the initial and final iterations.
415 
416    Level: advanced
417 
418    Notes:
419    This method combines the benefits of SNES_NORM_INITIAL_ONLY and SNES_NORM_FINAL_ONLY.
420 
421 .seealso: SNESNormSchedule, SNESSetNormSchedule(), SNES_NORM_SNES_NORM_INITIAL_ONLY, SNES_NORM_FINAL_ONLY
422 M*/
423 
424 
425 PETSC_EXTERN PetscErrorCode SNESSetNormSchedule(SNES,SNESNormSchedule);
426 PETSC_EXTERN PetscErrorCode SNESGetNormSchedule(SNES,SNESNormSchedule*);
427 
428 /*E
429     SNESFunctionType - Type of function computed
430 
431    Level: advanced
432 
433    Support for these is highly dependent on the solver.
434 
435 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPSetNormType(),
436           KSPSetConvergenceTest(), KSPSetPCSide()
437 E*/
438 typedef enum {SNES_FUNCTION_DEFAULT          = -1,
439               SNES_FUNCTION_UNPRECONDITIONED =  0,
440               SNES_FUNCTION_PRECONDITIONED   =  1} SNESFunctionType;
441 PETSC_EXTERN const char *const*const SNESFunctionTypes;
442 
443 PETSC_EXTERN PetscErrorCode SNESSetFunctionType(SNES,SNESFunctionType);
444 PETSC_EXTERN PetscErrorCode SNESGetFunctionType(SNES,SNESFunctionType*);
445 
446 PETSC_EXTERN PetscErrorCode SNESSetGS(SNES,PetscErrorCode (*SNESGSFunction)(SNES,Vec,Vec,void*),void*);
447 PETSC_EXTERN PetscErrorCode SNESGetGS(SNES,PetscErrorCode (**SNESGSFunction)(SNES,Vec,Vec,void*),void**);
448 PETSC_EXTERN PetscErrorCode SNESSetUseGS(SNES,PetscBool);
449 PETSC_EXTERN PetscErrorCode SNESGetUseGS(SNES,PetscBool *);
450 PETSC_EXTERN PetscErrorCode SNESComputeGS(SNES,Vec,Vec);
451 
452 PETSC_EXTERN PetscErrorCode SNESGSSetSweeps(SNES,PetscInt);
453 PETSC_EXTERN PetscErrorCode SNESGSGetSweeps(SNES,PetscInt *);
454 PETSC_EXTERN PetscErrorCode SNESGSSetTolerances(SNES,PetscReal,PetscReal,PetscReal,PetscInt);
455 PETSC_EXTERN PetscErrorCode SNESGSGetTolerances(SNES,PetscReal*,PetscReal*,PetscReal*,PetscInt*);
456 
457 PETSC_EXTERN PetscErrorCode SNESUpdateCheckJacobian(SNES,PetscInt);
458 
459 PETSC_EXTERN PetscErrorCode SNESShellGetContext(SNES,void**);
460 PETSC_EXTERN PetscErrorCode SNESShellSetContext(SNES,void*);
461 PETSC_EXTERN PetscErrorCode SNESShellSetSolve(SNES,PetscErrorCode (*)(SNES,Vec));
462 
463 /* --------- Routines specifically for line search methods --------------- */
464 
465 typedef struct _p_LineSearch* SNESLineSearch;
466 
467 /*S
468      SNESLineSearch - Abstract PETSc object that manages line-search operations
469 
470    Level: beginner
471 
472   Concepts: nonlinear solvers, line search
473 
474 .seealso:  SNESLineSearchCreate(), SNESLineSearchSetType(), SNES
475 S*/
476 
477 /*J
478     SNESLineSearchType - String with the name of a PETSc line search method
479 
480    Level: beginner
481 
482 .seealso: SNESLineSearchSetType(), SNES
483 J*/
484 
485 typedef const char* SNESLineSearchType;
486 #define SNESLINESEARCHBT                 "bt"
487 #define SNESLINESEARCHBASIC              "basic"
488 #define SNESLINESEARCHL2                 "l2"
489 #define SNESLINESEARCHCP                 "cp"
490 #define SNESLINESEARCHSHELL              "shell"
491 
492 PETSC_EXTERN PetscBool         SNESRegisterAllCalled;
493 PETSC_EXTERN PetscFunctionList SNESList;
494 PETSC_EXTERN PetscClassId      SNESLINESEARCH_CLASSID;
495 PETSC_EXTERN PetscBool         SNESLineSearchRegisterAllCalled;
496 PETSC_EXTERN PetscFunctionList SNESLineSearchList;
497 PETSC_EXTERN PetscLogEvent     SNESLineSearch_Apply;
498 
499 #define SNES_LINESEARCH_ORDER_LINEAR    1
500 #define SNES_LINESEARCH_ORDER_QUADRATIC 2
501 #define SNES_LINESEARCH_ORDER_CUBIC     3
502 
503 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVIProjectFunc)(SNES,Vec);
504 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVINormFunc)(SNES,Vec,Vec,PetscReal *);
505 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchApplyFunc)(SNESLineSearch);
506 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchUserFunc)(SNESLineSearch, void *);
507 
508 PETSC_EXTERN PetscErrorCode SNESLineSearchCreate(MPI_Comm, SNESLineSearch*);
509 PETSC_EXTERN PetscErrorCode SNESLineSearchReset(SNESLineSearch);
510 PETSC_EXTERN PetscErrorCode SNESLineSearchView(SNESLineSearch,PetscViewer);
511 PETSC_EXTERN PetscErrorCode SNESLineSearchDestroy(SNESLineSearch *);
512 PETSC_EXTERN PetscErrorCode SNESLineSearchSetType(SNESLineSearch, SNESLineSearchType);
513 PETSC_EXTERN PetscErrorCode SNESLineSearchSetFromOptions(SNESLineSearch);
514 PETSC_EXTERN PetscErrorCode SNESLineSearchSetFunction(SNESLineSearch,PetscErrorCode (*)(SNES,Vec,Vec));
515 PETSC_EXTERN PetscErrorCode SNESLineSearchSetUp(SNESLineSearch);
516 PETSC_EXTERN PetscErrorCode SNESLineSearchApply(SNESLineSearch, Vec, Vec, PetscReal *, Vec);
517 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheck(SNESLineSearch,Vec,Vec,PetscBool *);
518 PETSC_EXTERN PetscErrorCode SNESLineSearchPostCheck(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *);
519 PETSC_EXTERN PetscErrorCode SNESLineSearchSetWorkVecs(SNESLineSearch, PetscInt);
520 
521 /* set the functions for precheck and postcheck */
522 
523 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPreCheck(SNESLineSearch, PetscErrorCode (*SNESLineSearchPreCheckFunction)(SNESLineSearch,Vec,Vec,PetscBool*,void*), void *ctx);
524 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPostCheck(SNESLineSearch, PetscErrorCode (*SNESLineSearchPostCheckFunction)(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *,void*), void *ctx);
525 
526 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPreCheck(SNESLineSearch, PetscErrorCode (**SNESLineSearchPreCheckFunction)(SNESLineSearch,Vec,Vec,PetscBool*,void*), void **ctx);
527 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPostCheck(SNESLineSearch, PetscErrorCode (**SNESLineSearchPostCheckFunction)(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *,void*), void **ctx);
528 
529 /* set the functions for VI-specific line search operations */
530 
531 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc, SNESLineSearchVINormFunc);
532 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc*, SNESLineSearchVINormFunc*);
533 
534 /* pointers to the associated SNES in order to be able to get the function evaluation out */
535 PETSC_EXTERN PetscErrorCode SNESLineSearchSetSNES(SNESLineSearch,SNES);
536 PETSC_EXTERN PetscErrorCode SNESLineSearchGetSNES(SNESLineSearch,SNES*);
537 
538 /* set and get the parameters and vectors */
539 PETSC_EXTERN PetscErrorCode SNESLineSearchGetTolerances(SNESLineSearch,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscInt*);
540 PETSC_EXTERN PetscErrorCode SNESLineSearchSetTolerances(SNESLineSearch,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscInt);
541 
542 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheckPicard(SNESLineSearch,Vec,Vec,PetscBool*,void*);
543 
544 PETSC_EXTERN PetscErrorCode SNESLineSearchGetLambda(SNESLineSearch,PetscReal*);
545 PETSC_EXTERN PetscErrorCode SNESLineSearchSetLambda(SNESLineSearch,PetscReal);
546 
547 PETSC_EXTERN PetscErrorCode SNESLineSearchGetDamping(SNESLineSearch,PetscReal*);
548 PETSC_EXTERN PetscErrorCode SNESLineSearchSetDamping(SNESLineSearch,PetscReal);
549 
550 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOrder(SNESLineSearch,PetscInt *order);
551 PETSC_EXTERN PetscErrorCode SNESLineSearchSetOrder(SNESLineSearch,PetscInt order);
552 
553 PETSC_EXTERN PetscErrorCode SNESLineSearchGetSuccess(SNESLineSearch, PetscBool*);
554 PETSC_EXTERN PetscErrorCode SNESLineSearchSetSuccess(SNESLineSearch, PetscBool);
555 
556 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVecs(SNESLineSearch,Vec*,Vec*,Vec*,Vec*,Vec*);
557 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVecs(SNESLineSearch,Vec,Vec,Vec,Vec,Vec);
558 
559 PETSC_EXTERN PetscErrorCode SNESLineSearchGetNorms(SNESLineSearch, PetscReal *, PetscReal *, PetscReal *);
560 PETSC_EXTERN PetscErrorCode SNESLineSearchSetNorms(SNESLineSearch, PetscReal, PetscReal, PetscReal);
561 PETSC_EXTERN PetscErrorCode SNESLineSearchComputeNorms(SNESLineSearch);
562 PETSC_EXTERN PetscErrorCode SNESLineSearchSetComputeNorms(SNESLineSearch, PetscBool);
563 
564 PETSC_EXTERN PetscErrorCode SNESLineSearchSetMonitor(SNESLineSearch, PetscBool);
565 PETSC_EXTERN PetscErrorCode SNESLineSearchGetMonitor(SNESLineSearch, PetscViewer*);
566 
567 PETSC_EXTERN PetscErrorCode SNESLineSearchAppendOptionsPrefix(SNESLineSearch, const char prefix[]);
568 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOptionsPrefix(SNESLineSearch, const char *prefix[]);
569 
570 
571 /* Shell interface functions */
572 PETSC_EXTERN PetscErrorCode SNESLineSearchShellSetUserFunc(SNESLineSearch,SNESLineSearchUserFunc,void*);
573 PETSC_EXTERN PetscErrorCode SNESLineSearchShellGetUserFunc(SNESLineSearch,SNESLineSearchUserFunc*,void**);
574 
575 /* BT interface functions */
576 PETSC_EXTERN PetscErrorCode SNESLineSearchBTSetAlpha(SNESLineSearch, PetscReal);
577 PETSC_EXTERN PetscErrorCode SNESLineSearchBTGetAlpha(SNESLineSearch, PetscReal*);
578 
579 /*register line search types */
580 PETSC_EXTERN PetscErrorCode SNESLineSearchRegister(const char[],PetscErrorCode(*)(SNESLineSearch));
581 PETSC_EXTERN PetscErrorCode SNESLineSearchRegisterAll(void);
582 
583 /* Routines for VI solver */
584 PETSC_EXTERN PetscErrorCode SNESVISetVariableBounds(SNES,Vec,Vec);
585 PETSC_EXTERN PetscErrorCode SNESVISetComputeVariableBounds(SNES, PetscErrorCode (*)(SNES,Vec,Vec));
586 PETSC_EXTERN PetscErrorCode SNESVIGetInactiveSet(SNES,IS*);
587 PETSC_EXTERN PetscErrorCode SNESVIGetActiveSetIS(SNES,Vec,Vec,IS*);
588 PETSC_EXTERN PetscErrorCode SNESVIComputeInactiveSetFnorm(SNES,Vec,Vec,PetscReal*);
589 PETSC_EXTERN PetscErrorCode SNESVISetRedundancyCheck(SNES,PetscErrorCode(*)(SNES,IS,IS*,void*),void*);
590 #define SNES_VI_INF   1.0e20
591 #define SNES_VI_NINF -1.0e20
592 
593 PETSC_EXTERN PetscErrorCode SNESTestLocalMin(SNES);
594 
595 /* Should this routine be private? */
596 PETSC_EXTERN PetscErrorCode SNESComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*);
597 
598 PETSC_EXTERN PetscErrorCode SNESSetDM(SNES,DM);
599 PETSC_EXTERN PetscErrorCode SNESGetDM(SNES,DM*);
600 PETSC_EXTERN PetscErrorCode SNESSetPC(SNES,SNES);
601 PETSC_EXTERN PetscErrorCode SNESGetPC(SNES,SNES*);
602 PETSC_EXTERN PetscErrorCode SNESApplyPC(SNES,Vec,Vec,PetscReal*,Vec);
603 PETSC_EXTERN PetscErrorCode SNESGetPCFunction(SNES,Vec,PetscReal*);
604 PETSC_EXTERN PetscErrorCode SNESComputeFunctionDefaultPC(SNES,Vec,Vec);
605 PETSC_EXTERN PetscErrorCode SNESSetPCSide(SNES,PCSide);
606 PETSC_EXTERN PetscErrorCode SNESGetPCSide(SNES,PCSide*);
607 PETSC_EXTERN PetscErrorCode SNESSetLineSearch(SNES,SNESLineSearch);
608 PETSC_EXTERN PetscErrorCode SNESGetLineSearch(SNES,SNESLineSearch*);
609 PETSC_EXTERN PetscErrorCode SNESRestrictHookAdd(SNES,PetscErrorCode (*)(SNES,SNES,void*),void*);
610 PETSC_EXTERN PetscErrorCode SNESRestrictHooksRun(SNES,SNES);
611 
612 PETSC_DEPRECATED("Use SNESGetLineSearch()") PETSC_STATIC_INLINE PetscErrorCode SNESGetSNESLineSearch(SNES snes,SNESLineSearch *ls) {return SNESGetLineSearch(snes,ls);}
613 PETSC_DEPRECATED("Use SNESSetLineSearch()") PETSC_STATIC_INLINE PetscErrorCode SNESSetSNESLineSearch(SNES snes,SNESLineSearch ls) {return SNESSetLineSearch(snes,ls);}
614 
615 PETSC_EXTERN PetscErrorCode SNESSetUpMatrices(SNES);
616 PETSC_EXTERN PetscErrorCode DMSNESSetFunction(DM,PetscErrorCode(*SNESFunction)(SNES,Vec,Vec,void*),void*);
617 PETSC_EXTERN PetscErrorCode DMSNESGetFunction(DM,PetscErrorCode(**SNESSetFunction)(SNES,Vec,Vec,void*),void**);
618 PETSC_EXTERN PetscErrorCode DMSNESSetGS(DM,PetscErrorCode(*SNESGSFunction)(SNES,Vec,Vec,void*),void*);
619 PETSC_EXTERN PetscErrorCode DMSNESGetGS(DM,PetscErrorCode(**SNESGSFunction)(SNES,Vec,Vec,void*),void**);
620 PETSC_EXTERN PetscErrorCode DMSNESSetJacobian(DM,PetscErrorCode(*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
621 PETSC_EXTERN PetscErrorCode DMSNESGetJacobian(DM,PetscErrorCode(**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
622 PETSC_EXTERN PetscErrorCode DMSNESSetPicard(DM,PetscErrorCode(*SNESFunction)(SNES,Vec,Vec,void*),PetscErrorCode(*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
623 PETSC_EXTERN PetscErrorCode DMSNESGetPicard(DM,PetscErrorCode(**SNESFunction)(SNES,Vec,Vec,void*),PetscErrorCode(**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
624 PETSC_EXTERN PetscErrorCode DMSNESSetObjective(DM,PetscErrorCode (*SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void*);
625 PETSC_EXTERN PetscErrorCode DMSNESGetObjective(DM,PetscErrorCode (**SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void**);
626 
627 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESFunction)(DMDALocalInfo*,void*,void*,void*);
628 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESJacobian)(DMDALocalInfo*,void*,Mat,Mat,MatStructure*,void*);
629 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESObjective)(DMDALocalInfo*,void*,PetscReal*,void*);
630 
631 PETSC_EXTERN PetscErrorCode DMDASNESSetFunctionLocal(DM,InsertMode,DMDASNESFunction,void*);
632 PETSC_EXTERN PetscErrorCode DMDASNESSetJacobianLocal(DM,DMDASNESJacobian,void*);
633 PETSC_EXTERN PetscErrorCode DMDASNESSetObjectiveLocal(DM,DMDASNESObjective,void*);
634 PETSC_EXTERN PetscErrorCode DMDASNESSetPicardLocal(DM,InsertMode,PetscErrorCode (*)(DMDALocalInfo*,void*,void*,void*),PetscErrorCode (*)(DMDALocalInfo*,void*,Mat,Mat,MatStructure*,void*),void*);
635 
636 PETSC_EXTERN PetscErrorCode DMSNESSetFunctionLocal(DM,PetscErrorCode (*)(DM,Vec,Vec,void*),void*);
637 PETSC_EXTERN PetscErrorCode DMSNESSetJacobianLocal(DM,PetscErrorCode (*)(DM,Vec,Mat,Mat,MatStructure*,void*),void*);
638 
639 /* Routines for Multiblock solver */
640 PETSC_EXTERN PetscErrorCode SNESMultiblockSetFields(SNES, const char [], PetscInt, const PetscInt *);
641 PETSC_EXTERN PetscErrorCode SNESMultiblockSetIS(SNES, const char [], IS);
642 PETSC_EXTERN PetscErrorCode SNESMultiblockSetBlockSize(SNES, PetscInt);
643 PETSC_EXTERN PetscErrorCode SNESMultiblockSetType(SNES, PCCompositeType);
644 
645 /*J
646     SNESMSType - String with the name of a PETSc SNESMS method.
647 
648    Level: intermediate
649 
650 .seealso: SNESMSSetType(), SNES
651 J*/
652 typedef const char* SNESMSType;
653 #define SNESMSM62       "m62"
654 #define SNESMSEULER     "euler"
655 #define SNESMSJAMESON83 "jameson83"
656 #define SNESMSVLTP21    "vltp21"
657 #define SNESMSVLTP31    "vltp31"
658 #define SNESMSVLTP41    "vltp41"
659 #define SNESMSVLTP51    "vltp51"
660 #define SNESMSVLTP61    "vltp61"
661 
662 PETSC_EXTERN PetscErrorCode SNESMSRegister(SNESMSType,PetscInt,PetscInt,PetscReal,const PetscReal[],const PetscReal[],const PetscReal[]);
663 PETSC_EXTERN PetscErrorCode SNESMSSetType(SNES,SNESMSType);
664 PETSC_EXTERN PetscErrorCode SNESMSFinalizePackage(void);
665 PETSC_EXTERN PetscErrorCode SNESMSInitializePackage(void);
666 PETSC_EXTERN PetscErrorCode SNESMSRegisterDestroy(void);
667 PETSC_EXTERN PetscErrorCode SNESMSRegisterAll(void);
668 
669 /* routines for NGMRES solver */
670 
671 typedef enum {
672   SNES_NGMRES_RESTART_NONE       = 0,
673   SNES_NGMRES_RESTART_PERIODIC   = 1,
674   SNES_NGMRES_RESTART_DIFFERENCE = 2} SNESNGMRESRestartType;
675 PETSC_EXTERN const char *const SNESNGMRESRestartTypes[];
676 
677 typedef enum {
678   SNES_NGMRES_SELECT_NONE       = 0,
679   SNES_NGMRES_SELECT_DIFFERENCE = 1,
680   SNES_NGMRES_SELECT_LINESEARCH = 2} SNESNGMRESSelectType;
681 PETSC_EXTERN const char *const SNESNGMRESSelectTypes[];
682 
683 PETSC_EXTERN PetscErrorCode SNESNGMRESSetRestartType(SNES, SNESNGMRESRestartType);
684 PETSC_EXTERN PetscErrorCode SNESNGMRESSetSelectType(SNES, SNESNGMRESSelectType);
685 
686 /* routines for NCG solver */
687 
688 typedef enum {
689   SNES_NCG_FR    = 0,
690   SNES_NCG_PRP   = 1,
691   SNES_NCG_HS    = 2,
692   SNES_NCG_DY    = 3,
693   SNES_NCG_CD    = 4} SNESNCGType;
694 PETSC_EXTERN const char *const SNESNCGTypes[];
695 
696 PETSC_EXTERN PetscErrorCode SNESNCGSetType(SNES, SNESNCGType);
697 
698 typedef enum {SNES_QN_SCALE_NONE       = 0,
699               SNES_QN_SCALE_SHANNO     = 1,
700               SNES_QN_SCALE_LINESEARCH = 2,
701               SNES_QN_SCALE_JACOBIAN   = 3} SNESQNScaleType;
702 PETSC_EXTERN const char *const SNESQNScaleTypes[];
703 typedef enum {SNES_QN_RESTART_NONE     = 0,
704               SNES_QN_RESTART_POWELL   = 1,
705               SNES_QN_RESTART_PERIODIC = 2} SNESQNRestartType;
706 PETSC_EXTERN const char *const SNESQNRestartTypes[];
707 
708 PETSC_EXTERN PetscErrorCode SNESQNSetScaleType(SNES, SNESQNScaleType);
709 PETSC_EXTERN PetscErrorCode SNESQNSetRestartType(SNES, SNESQNRestartType);
710 
711 PETSC_EXTERN PetscErrorCode SNESNASMGetSubdomains(SNES,PetscInt*,SNES**,VecScatter**,VecScatter**,VecScatter**);
712 PETSC_EXTERN PetscErrorCode SNESNASMSetSubdomains(SNES,PetscInt,SNES*,VecScatter*,VecScatter*,VecScatter*);
713 PETSC_EXTERN PetscErrorCode SNESNASMSetDamping(SNES,PetscReal);
714 PETSC_EXTERN PetscErrorCode SNESNASMGetDamping(SNES,PetscReal*);
715 PETSC_EXTERN PetscErrorCode SNESNASMGetSubdomainVecs(SNES,PetscInt*,Vec**,Vec**,Vec**,Vec**);
716 PETSC_EXTERN PetscErrorCode SNESNASMSetComputeFinalJacobian(SNES,PetscBool);
717 
718 #endif
719