xref: /petsc/include/petscsnes.h (revision 1147fc2a6bf7922defbbca15fc6c33f234803ff0)
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 <petscdmda.h>
8 
9 /*S
10      SNES - Abstract PETSc object that manages all nonlinear solves
11 
12    Level: beginner
13 
14   Concepts: nonlinear solvers
15 
16 .seealso:  SNESCreate(), SNESSetType(), SNESType, TS, KSP, KSP, PC
17 S*/
18 typedef struct _p_SNES* SNES;
19 
20 /*J
21     SNESType - String with the name of a PETSc SNES method or the creation function
22        with an optional dynamic library name, for example
23        http://www.mcs.anl.gov/petsc/lib.a:mysnescreate()
24 
25    Level: beginner
26 
27 .seealso: SNESSetType(), SNES
28 J*/
29 typedef const char* SNESType;
30 #define SNESNEWTONLS     "newtonls"
31 #define SNESNEWTONTR     "newtontr"
32 #define SNESPYTHON       "python"
33 #define SNESTEST         "test"
34 #define SNESNRICHARDSON  "nrichardson"
35 #define SNESKSPONLY      "ksponly"
36 #define SNESVINEWTONRSLS "vinewtonrsls"
37 #define SNESVINEWTONSSLS "vinewtonssls"
38 #define SNESNGMRES       "ngmres"
39 #define SNESQN           "qn"
40 #define SNESSHELL        "shell"
41 #define SNESGS           "gs"
42 #define SNESNCG          "ncg"
43 #define SNESFAS          "fas"
44 #define SNESMS           "ms"
45 #define SNESNASM         "nasm"
46 
47 /* Logging support */
48 PETSC_EXTERN PetscClassId SNES_CLASSID;
49 PETSC_EXTERN PetscClassId DMSNES_CLASSID;
50 
51 PETSC_EXTERN PetscErrorCode SNESInitializePackage(const char[]);
52 
53 PETSC_EXTERN PetscErrorCode SNESCreate(MPI_Comm,SNES*);
54 PETSC_EXTERN PetscErrorCode SNESReset(SNES);
55 PETSC_EXTERN PetscErrorCode SNESDestroy(SNES*);
56 PETSC_EXTERN PetscErrorCode SNESSetType(SNES,SNESType);
57 PETSC_EXTERN PetscErrorCode SNESMonitor(SNES,PetscInt,PetscReal);
58 PETSC_EXTERN PetscErrorCode SNESMonitorSet(SNES,PetscErrorCode(*)(SNES,PetscInt,PetscReal,void*),void *,PetscErrorCode (*)(void**));
59 PETSC_EXTERN PetscErrorCode SNESMonitorCancel(SNES);
60 PETSC_EXTERN PetscErrorCode SNESSetConvergenceHistory(SNES,PetscReal[],PetscInt[],PetscInt,PetscBool );
61 PETSC_EXTERN PetscErrorCode SNESGetConvergenceHistory(SNES,PetscReal*[],PetscInt *[],PetscInt *);
62 PETSC_EXTERN PetscErrorCode SNESSetUp(SNES);
63 PETSC_EXTERN PetscErrorCode SNESSolve(SNES,Vec,Vec);
64 PETSC_EXTERN PetscErrorCode SNESSetErrorIfNotConverged(SNES,PetscBool );
65 PETSC_EXTERN PetscErrorCode SNESGetErrorIfNotConverged(SNES,PetscBool  *);
66 
67 
68 PETSC_EXTERN PetscErrorCode SNESAddOptionsChecker(PetscErrorCode (*)(SNES));
69 
70 PETSC_EXTERN PetscErrorCode SNESSetUpdate(SNES, PetscErrorCode (*)(SNES, PetscInt));
71 PETSC_EXTERN PetscErrorCode SNESDefaultUpdate(SNES, PetscInt);
72 
73 PETSC_EXTERN PetscErrorCode SNESRegisterDestroy(void);
74 PETSC_EXTERN PetscErrorCode SNESRegisterAll(const char[]);
75 
76 PETSC_EXTERN PetscErrorCode SNESRegister(const char[],const char[],const char[],PetscErrorCode (*)(SNES));
77 
78 /*MC
79    SNESRegisterDynamic - Adds a method to the nonlinear solver package.
80 
81    Synopsis:
82     #include "petscsnes.h"
83    PetscErrorCode SNESRegisterDynamic(const char *name_solver,const char *path,const char *name_create,PetscErrorCode (*routine_create)(SNES))
84 
85    Not collective
86 
87    Input Parameters:
88 +  name_solver - name of a new user-defined solver
89 .  path - path (either absolute or relative) the library containing this solver
90 .  name_create - name of routine to create method context
91 -  routine_create - routine to create method context
92 
93    Notes:
94    SNESRegisterDynamic() may be called multiple times to add several user-defined solvers.
95 
96    If dynamic libraries are used, then the fourth input argument (routine_create)
97    is ignored.
98 
99    Environmental variables such as ${PETSC_ARCH}, ${PETSC_DIR}, ${PETSC_LIB_DIR},
100    and others of the form ${any_environmental_variable} occuring in pathname will be
101    replaced with appropriate values.
102 
103    Sample usage:
104 .vb
105    SNESRegisterDynamic("my_solver",/home/username/my_lib/lib/libg/solaris/mylib.a,
106                 "MySolverCreate",MySolverCreate);
107 .ve
108 
109    Then, your solver can be chosen with the procedural interface via
110 $     SNESSetType(snes,"my_solver")
111    or at runtime via the option
112 $     -snes_type my_solver
113 
114    Level: advanced
115 
116     Note: If your function is not being put into a shared library then use SNESRegister() instead
117 
118 .keywords: SNES, nonlinear, register
119 
120 .seealso: SNESRegisterAll(), SNESRegisterDestroy()
121 M*/
122 #if defined(PETSC_USE_DYNAMIC_LIBRARIES)
123 #define SNESRegisterDynamic(a,b,c,d) SNESRegister(a,b,c,0)
124 #else
125 #define SNESRegisterDynamic(a,b,c,d) SNESRegister(a,b,c,d)
126 #endif
127 
128 PETSC_EXTERN PetscErrorCode SNESGetKSP(SNES,KSP*);
129 PETSC_EXTERN PetscErrorCode SNESSetKSP(SNES,KSP);
130 PETSC_EXTERN PetscErrorCode SNESGetSolution(SNES,Vec*);
131 PETSC_EXTERN PetscErrorCode SNESGetSolutionUpdate(SNES,Vec*);
132 PETSC_EXTERN PetscErrorCode SNESGetRhs(SNES,Vec*);
133 PETSC_EXTERN PetscErrorCode SNESView(SNES,PetscViewer);
134 PETSC_EXTERN PetscErrorCode SNESLoad(SNES,PetscViewer);
135 
136 #define SNES_FILE_CLASSID 1211224
137 
138 PETSC_EXTERN PetscErrorCode SNESSetOptionsPrefix(SNES,const char[]);
139 PETSC_EXTERN PetscErrorCode SNESAppendOptionsPrefix(SNES,const char[]);
140 PETSC_EXTERN PetscErrorCode SNESGetOptionsPrefix(SNES,const char*[]);
141 PETSC_EXTERN PetscErrorCode SNESSetFromOptions(SNES);
142 PETSC_EXTERN PetscErrorCode SNESDefaultGetWork(SNES,PetscInt);
143 
144 PETSC_EXTERN PetscErrorCode MatCreateSNESMF(SNES,Mat*);
145 PETSC_EXTERN PetscErrorCode MatMFFDComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
146 
147 PETSC_EXTERN PetscErrorCode MatDAADSetSNES(Mat,SNES);
148 
149 PETSC_EXTERN PetscErrorCode SNESGetType(SNES,SNESType*);
150 PETSC_EXTERN PetscErrorCode SNESMonitorDefault(SNES,PetscInt,PetscReal,void *);
151 PETSC_EXTERN PetscErrorCode SNESMonitorRange(SNES,PetscInt,PetscReal,void *);
152 PETSC_EXTERN PetscErrorCode SNESMonitorRatio(SNES,PetscInt,PetscReal,void *);
153 PETSC_EXTERN PetscErrorCode SNESMonitorSetRatio(SNES,PetscViewer);
154 PETSC_EXTERN PetscErrorCode SNESMonitorSolution(SNES,PetscInt,PetscReal,void *);
155 PETSC_EXTERN PetscErrorCode SNESMonitorResidual(SNES,PetscInt,PetscReal,void *);
156 PETSC_EXTERN PetscErrorCode SNESMonitorSolutionUpdate(SNES,PetscInt,PetscReal,void *);
157 PETSC_EXTERN PetscErrorCode SNESMonitorDefaultShort(SNES,PetscInt,PetscReal,void *);
158 PETSC_EXTERN PetscErrorCode SNESMonitorJacUpdateSpectrum(SNES,PetscInt,PetscReal,void *);
159 PETSC_EXTERN PetscErrorCode SNESSetTolerances(SNES,PetscReal,PetscReal,PetscReal,PetscInt,PetscInt);
160 PETSC_EXTERN PetscErrorCode SNESGetTolerances(SNES,PetscReal*,PetscReal*,PetscReal*,PetscInt*,PetscInt*);
161 PETSC_EXTERN PetscErrorCode SNESSetTrustRegionTolerance(SNES,PetscReal);
162 PETSC_EXTERN PetscErrorCode SNESGetFunctionNorm(SNES,PetscReal*);
163 PETSC_EXTERN PetscErrorCode SNESSetFunctionNorm(SNES,PetscReal);
164 PETSC_EXTERN PetscErrorCode SNESGetIterationNumber(SNES,PetscInt*);
165 PETSC_EXTERN PetscErrorCode SNESSetIterationNumber(SNES,PetscInt);
166 
167 PETSC_EXTERN PetscErrorCode SNESGetNonlinearStepFailures(SNES,PetscInt*);
168 PETSC_EXTERN PetscErrorCode SNESSetMaxNonlinearStepFailures(SNES,PetscInt);
169 PETSC_EXTERN PetscErrorCode SNESGetMaxNonlinearStepFailures(SNES,PetscInt*);
170 PETSC_EXTERN PetscErrorCode SNESGetNumberFunctionEvals(SNES,PetscInt*);
171 
172 PETSC_EXTERN PetscErrorCode SNESSetLagPreconditioner(SNES,PetscInt);
173 PETSC_EXTERN PetscErrorCode SNESGetLagPreconditioner(SNES,PetscInt*);
174 PETSC_EXTERN PetscErrorCode SNESSetLagJacobian(SNES,PetscInt);
175 PETSC_EXTERN PetscErrorCode SNESGetLagJacobian(SNES,PetscInt*);
176 PETSC_EXTERN PetscErrorCode SNESSetGridSequence(SNES,PetscInt);
177 
178 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveIterations(SNES,PetscInt*);
179 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveFailures(SNES,PetscInt*);
180 PETSC_EXTERN PetscErrorCode SNESSetMaxLinearSolveFailures(SNES,PetscInt);
181 PETSC_EXTERN PetscErrorCode SNESGetMaxLinearSolveFailures(SNES,PetscInt*);
182 
183 PETSC_EXTERN PetscErrorCode SNESKSPSetUseEW(SNES,PetscBool );
184 PETSC_EXTERN PetscErrorCode SNESKSPGetUseEW(SNES,PetscBool *);
185 PETSC_EXTERN PetscErrorCode SNESKSPSetParametersEW(SNES,PetscInt,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal);
186 PETSC_EXTERN PetscErrorCode SNESKSPGetParametersEW(SNES,PetscInt*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*);
187 
188 PETSC_EXTERN PetscErrorCode SNESMonitorLGCreate(const char[],const char[],int,int,int,int,PetscDrawLG*);
189 PETSC_EXTERN PetscErrorCode SNESMonitorLGResidualNorm(SNES,PetscInt,PetscReal,void*);
190 PETSC_EXTERN PetscErrorCode SNESMonitorLGDestroy(PetscDrawLG*);
191 PETSC_EXTERN PetscErrorCode SNESMonitorLGRange(SNES,PetscInt,PetscReal,void*);
192 
193 PETSC_EXTERN PetscErrorCode SNESSetApplicationContext(SNES,void *);
194 PETSC_EXTERN PetscErrorCode SNESGetApplicationContext(SNES,void *);
195 PETSC_EXTERN PetscErrorCode SNESSetComputeApplicationContext(SNES,PetscErrorCode (*)(SNES,void**),PetscErrorCode (*)(void**));
196 
197 PETSC_EXTERN PetscErrorCode SNESPythonSetType(SNES,const char[]);
198 
199 PETSC_EXTERN PetscErrorCode SNESSetFunctionDomainError(SNES);
200 PETSC_EXTERN PetscErrorCode SNESGetFunctionDomainError(SNES, PetscBool *);
201 
202 /*E
203     SNESConvergedReason - reason a SNES method was said to
204          have converged or diverged
205 
206    Level: beginner
207 
208    The two most common reasons for divergence are
209 $   1) an incorrectly coded or computed Jacobian or
210 $   2) failure or lack of convergence in the linear system (in this case we recommend
211 $      testing with -pc_type lu to eliminate the linear solver as the cause of the problem).
212 
213    Diverged Reasons:
214 .    SNES_DIVERGED_LOCAL_MIN - this can only occur when using the line-search variant of SNES.
215        The line search wants to minimize Q(alpha) = 1/2 || F(x + alpha s) ||^2_2  this occurs
216        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
217        you get Q'(alpha) = -F(x)^T F'(x)^(-1)^T F'(x+alpha s)F(x+alpha s); when alpha = 0
218        Q'(0) = - ||F(x)||^2_2 which is always NEGATIVE if F'(x) is invertible. This means the Newton
219        direction is a descent direction and the line search should succeed if alpha is small enough.
220 
221        If F'(x) is NOT invertible AND F'(x)^T F(x) = 0 then Q'(0) = 0 and the Newton direction
222        is NOT a descent direction so the line search will fail. All one can do at this point
223        is change the initial guess and try again.
224 
225        An alternative explanation: Newton's method can be regarded as replacing the function with
226        its linear approximation and minimizing the 2-norm of that. That is F(x+s) approx F(x) + F'(x)s
227        so we minimize || F(x) + F'(x) s ||^2_2; do this using Least Squares. If F'(x) is invertible then
228        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
229        exists a nontrival (that is F'(x)s != 0) solution to the equation and this direction is
230        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)
231        = - (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
232        and F'(x)^T F'(x) has no negative eigenvalues Q'(0) < 0 so s is a descent direction and the line
233        search should succeed for small enough alpha.
234 
235        Note that this RARELY happens in practice. Far more likely the linear system is not being solved
236        (well enough?) or the Jacobian is wrong.
237 
238    SNES_DIVERGED_MAX_IT means that the solver reached the maximum number of iterations without satisfying any
239    convergence criteria. SNES_CONVERGED_ITS means that SNESSkipConverged() was chosen as the convergence test;
240    thus the usual convergence criteria have not been checked and may or may not be satisfied.
241 
242    Developer Notes: this must match finclude/petscsnes.h
243 
244        The string versions of these are in SNESConvergedReason, if you change any value here you must
245      also adjust that array.
246 
247    Each reason has its own manual page.
248 
249 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPConvergedReason, SNESSetConvergenceTest()
250 E*/
251 typedef enum {/* converged */
252               SNES_CONVERGED_FNORM_ABS         =  2, /* ||F|| < atol */
253               SNES_CONVERGED_FNORM_RELATIVE    =  3, /* ||F|| < rtol*||F_initial|| */
254               SNES_CONVERGED_SNORM_RELATIVE    =  4, /* Newton computed step size small; || delta x || < stol || x ||*/
255               SNES_CONVERGED_ITS               =  5, /* maximum iterations reached */
256               SNES_CONVERGED_TR_DELTA          =  7,
257               /* diverged */
258               SNES_DIVERGED_FUNCTION_DOMAIN     = -1, /* the new x location passed the function is not in the domain of F */
259               SNES_DIVERGED_FUNCTION_COUNT      = -2,
260               SNES_DIVERGED_LINEAR_SOLVE        = -3, /* the linear solve failed */
261               SNES_DIVERGED_FNORM_NAN           = -4,
262               SNES_DIVERGED_MAX_IT              = -5,
263               SNES_DIVERGED_LINE_SEARCH         = -6, /* the line search failed */
264               SNES_DIVERGED_INNER               = -7, /* inner solve failed */
265               SNES_DIVERGED_LOCAL_MIN           = -8, /* || J^T b || is small, implies converged to local minimum of F() */
266               SNES_CONVERGED_ITERATING          =  0} SNESConvergedReason;
267 PETSC_EXTERN const char *const*SNESConvergedReasons;
268 
269 /*MC
270      SNES_CONVERGED_FNORM_ABS - 2-norm(F) <= abstol
271 
272    Level: beginner
273 
274 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
275 
276 M*/
277 
278 /*MC
279      SNES_CONVERGED_FNORM_RELATIVE - 2-norm(F) <= rtol*2-norm(F(x_0)) where x_0 is the initial guess
280 
281    Level: beginner
282 
283 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
284 
285 M*/
286 
287 /*MC
288      SNES_CONVERGED_SNORM_RELATIVE - The 2-norm of the last step <= stol * 2-norm(x) where x is the current
289           solution and stol is the 4th argument to SNESSetTolerances()
290 
291      Options Database Keys:
292       -snes_stol <stol> - the step tolerance
293 
294    Level: beginner
295 
296 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
297 
298 M*/
299 
300 /*MC
301      SNES_DIVERGED_FUNCTION_COUNT - The user provided function has been called more times then the final
302          argument to SNESSetTolerances()
303 
304    Level: beginner
305 
306 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
307 
308 M*/
309 
310 /*MC
311      SNES_DIVERGED_FNORM_NAN - the 2-norm of the current function evaluation is not-a-number (NaN), this
312       is usually caused by a division of 0 by 0.
313 
314    Level: beginner
315 
316 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
317 
318 M*/
319 
320 /*MC
321      SNES_DIVERGED_MAX_IT - SNESSolve() has reached the maximum number of iterations requested
322 
323    Level: beginner
324 
325 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
326 
327 M*/
328 
329 /*MC
330      SNES_DIVERGED_LINE_SEARCH - The line search has failed. This only occurs for a SNES solvers that use a line search
331 
332    Level: beginner
333 
334 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances(), SNESLineSearch
335 
336 M*/
337 
338 /*MC
339      SNES_DIVERGED_LOCAL_MIN - the algorithm seems to have stagnated at a local minimum that is not zero.
340         See the manual page for SNESConvergedReason for more details
341 
342    Level: beginner
343 
344 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
345 
346 M*/
347 
348 /*MC
349      SNES_CONERGED_ITERATING - this only occurs if SNESGetConvergedReason() is called during the SNESSolve()
350 
351    Level: beginner
352 
353 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
354 
355 M*/
356 
357 PETSC_EXTERN PetscErrorCode SNESSetConvergenceTest(SNES,PetscErrorCode (*)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*),void*,PetscErrorCode (*)(void*));
358 PETSC_EXTERN PetscErrorCode SNESDefaultConverged(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
359 PETSC_EXTERN PetscErrorCode SNESSkipConverged(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
360 PETSC_EXTERN PetscErrorCode SNESGetConvergedReason(SNES,SNESConvergedReason*);
361 
362 PETSC_EXTERN PetscErrorCode SNESDMMeshComputeFunction(SNES,Vec,Vec,void*);
363 PETSC_EXTERN PetscErrorCode SNESDMMeshComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
364 
365 /* --------- Solving systems of nonlinear equations --------------- */
366 PETSC_EXTERN PetscErrorCode SNESSetFunction(SNES,Vec,PetscErrorCode (*SNESFunction)(SNES,Vec,Vec,void*),void*);
367 PETSC_EXTERN PetscErrorCode SNESGetFunction(SNES,Vec*,PetscErrorCode (**SNESFunction)(SNES,Vec,Vec,void*),void**);
368 PETSC_EXTERN PetscErrorCode SNESComputeFunction(SNES,Vec,Vec);
369 PETSC_EXTERN PetscErrorCode SNESSetJacobian(SNES,Mat,Mat,PetscErrorCode (*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
370 PETSC_EXTERN PetscErrorCode SNESGetJacobian(SNES,Mat*,Mat*,PetscErrorCode (**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
371 PETSC_EXTERN PetscErrorCode SNESDefaultObjectiveComputeFunctionFD(SNES,Vec,Vec,void*);
372 PETSC_EXTERN PetscErrorCode SNESDefaultComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
373 PETSC_EXTERN PetscErrorCode SNESDefaultComputeJacobianColor(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
374 PETSC_EXTERN PetscErrorCode SNESSetComputeInitialGuess(SNES,PetscErrorCode (*)(SNES,Vec,void*),void*);
375 PETSC_EXTERN PetscErrorCode SNESSetPicard(SNES,Vec,PetscErrorCode (*SNESFunction)(SNES,Vec,Vec,void*),Mat,Mat,PetscErrorCode (*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
376 PETSC_EXTERN PetscErrorCode SNESGetPicard(SNES,Vec*,PetscErrorCode (**SNESFunction)(SNES,Vec,Vec,void*),Mat*,Mat*,PetscErrorCode (**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
377 PETSC_EXTERN PetscErrorCode SNESSetInitialFunction(SNES,Vec);
378 PETSC_EXTERN PetscErrorCode SNESSetInitialFunctionNorm(SNES,PetscReal);
379 
380 PETSC_EXTERN PetscErrorCode SNESSetObjective(SNES,PetscErrorCode (*SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void*);
381 PETSC_EXTERN PetscErrorCode SNESGetObjective(SNES,PetscErrorCode (**SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void**);
382 PETSC_EXTERN PetscErrorCode SNESComputeObjective(SNES,Vec,PetscReal *);
383 
384 /*E
385     SNESNormType - Norm that is passed in the Krylov convergence
386        test routines.
387 
388    Level: advanced
389 
390    Support for these is highly dependent on the solver.
391 
392    Notes:
393    This is primarily used to turn off extra norm and function computation
394    when the solvers are composed.
395 
396 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPSetNormType(),
397           KSPSetConvergenceTest(), KSPSetPCSide()
398 E*/
399 
400 typedef enum {SNES_NORM_DEFAULT            = -1,
401               SNES_NORM_NONE               =  0,
402               SNES_NORM_FUNCTION           =  1,
403               SNES_NORM_INITIAL_ONLY       =  2,
404               SNES_NORM_FINAL_ONLY         =  3,
405               SNES_NORM_INITIAL_FINAL_ONLY =  4} SNESNormType;
406 PETSC_EXTERN const char *const*const SNESNormTypes;
407 /*MC
408     SNES_NORM_NONE - Don't compute function and its L2 norm.
409 
410    Level: advanced
411 
412     Notes:
413     This is most useful for stationary solvers with a fixed number of iterations used as smoothers.
414 
415 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_DEFAULT
416 M*/
417 
418 /*MC
419     SNES_NORM_FUNCTION - Compute the function and its L2 norm at each iteration.
420 
421    Level: advanced
422 
423     Notes:
424     Most solvers will use this no matter what norm type is passed to them.
425 
426 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_NONE
427 M*/
428 
429 /*MC
430     SNES_NORM_INITIAL_ONLY - Compute the function and its L2 at iteration 0, but do not update it.
431 
432    Level: advanced
433 
434    Notes:
435    This method is useful in composed methods, when a true solution might actually be found before SNESSolve() is called.
436    This option enables the solve to abort on the zeroth iteration if this is the case.
437 
438    For solvers that require the computation of the L2 norm of the function as part of the method, this merely cancels
439    the norm computation at the last iteration (if possible).
440 
441 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_FINAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
442 M*/
443 
444 /*MC
445     SNES_NORM_FINAL_ONLY - Compute the function and its L2 norm on only the final iteration.
446 
447    Level: advanced
448 
449    Notes:
450    For solvers that require the computation of the L2 norm of the function as part of the method, behaves
451    exactly as SNES_NORM_DEFAULT.  This method is useful when the function is gotten after SNESSolve and
452    used in subsequent computation for methods that do not need the norm computed during the rest of the
453    solution procedure.
454 
455 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_INITIAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
456 M*/
457 
458 /*MC
459     SNES_NORM_INITIAL_FINAL_ONLY - Compute the function and its L2 norm on only the initial and final iterations.
460 
461    Level: advanced
462 
463    Notes:
464    This method combines the benefits of SNES_NORM_INITIAL_ONLY and SNES_NORM_FINAL_ONLY.
465 
466 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_SNES_NORM_INITIAL_ONLY, SNES_NORM_FINAL_ONLY
467 M*/
468 
469 
470 PETSC_EXTERN PetscErrorCode SNESSetNormType(SNES,SNESNormType);
471 PETSC_EXTERN PetscErrorCode SNESGetNormType(SNES,SNESNormType*);
472 
473 PETSC_EXTERN PetscErrorCode SNESSetGS(SNES,PetscErrorCode (*SNESGSFunction)(SNES,Vec,Vec,void*),void*);
474 PETSC_EXTERN PetscErrorCode SNESGetGS(SNES,PetscErrorCode (**SNESGSFunction)(SNES,Vec,Vec,void*),void**);
475 PETSC_EXTERN PetscErrorCode SNESSetUseGS(SNES,PetscBool);
476 PETSC_EXTERN PetscErrorCode SNESGetUseGS(SNES,PetscBool *);
477 PETSC_EXTERN PetscErrorCode SNESComputeGS(SNES,Vec,Vec);
478 
479 PETSC_EXTERN PetscErrorCode SNESGSSetSweeps(SNES,PetscInt);
480 PETSC_EXTERN PetscErrorCode SNESGSGetSweeps(SNES,PetscInt *);
481 PETSC_EXTERN PetscErrorCode SNESGSSetTolerances(SNES,PetscReal,PetscReal,PetscReal,PetscInt);
482 PETSC_EXTERN PetscErrorCode SNESGSGetTolerances(SNES,PetscReal*,PetscReal*,PetscReal*,PetscInt*);
483 
484 PETSC_EXTERN PetscErrorCode SNESUpdateCheckJacobian(SNES,PetscInt);
485 
486 PETSC_EXTERN PetscErrorCode SNESShellGetContext(SNES,void**);
487 PETSC_EXTERN PetscErrorCode SNESShellSetContext(SNES,void*);
488 PETSC_EXTERN PetscErrorCode SNESShellSetSolve(SNES,PetscErrorCode (*)(SNES,Vec));
489 
490 /* --------- Routines specifically for line search methods --------------- */
491 
492 typedef struct _p_LineSearch* SNESLineSearch;
493 
494 /*S
495      SNESLineSearch - Abstract PETSc object that manages line-search operations
496 
497    Level: beginner
498 
499   Concepts: nonlinear solvers, line search
500 
501 .seealso:  SNESLineSearchCreate(), SNESLineSearchSetType(), SNES
502 S*/
503 
504 /*J
505     SNESLineSearchType - String with the name of a PETSc line search method
506 
507    Level: beginner
508 
509 .seealso: SNESLineSearchSetType(), SNES
510 J*/
511 
512 typedef const char* SNESLineSearchType;
513 #define SNESLINESEARCHBT                 "bt"
514 #define SNESLINESEARCHBASIC              "basic"
515 #define SNESLINESEARCHL2                 "l2"
516 #define SNESLINESEARCHCP                 "cp"
517 #define SNESLINESEARCHSHELL              "shell"
518 
519 PETSC_EXTERN PetscBool         SNESRegisterAllCalled;
520 PETSC_EXTERN PetscFunctionList SNESList;
521 PETSC_EXTERN PetscClassId      SNESLINESEARCH_CLASSID;
522 PETSC_EXTERN PetscBool         SNESLineSearchRegisterAllCalled;
523 PETSC_EXTERN PetscFunctionList SNESLineSearchList;
524 PETSC_EXTERN PetscLogEvent     SNESLineSearch_Apply;
525 
526 #define SNES_LINESEARCH_ORDER_LINEAR    1
527 #define SNES_LINESEARCH_ORDER_QUADRATIC 2
528 #define SNES_LINESEARCH_ORDER_CUBIC     3
529 
530 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVIProjectFunc)(SNES,Vec);
531 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVINormFunc)(SNES,Vec,Vec,PetscReal *);
532 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchApplyFunc)(SNESLineSearch);
533 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchUserFunc)(SNESLineSearch, void *);
534 
535 PETSC_EXTERN PetscErrorCode SNESLineSearchCreate(MPI_Comm, SNESLineSearch*);
536 PETSC_EXTERN PetscErrorCode SNESLineSearchReset(SNESLineSearch);
537 PETSC_EXTERN PetscErrorCode SNESLineSearchView(SNESLineSearch,PetscViewer);
538 PETSC_EXTERN PetscErrorCode SNESLineSearchDestroy(SNESLineSearch *);
539 PETSC_EXTERN PetscErrorCode SNESLineSearchSetType(SNESLineSearch, SNESLineSearchType);
540 PETSC_EXTERN PetscErrorCode SNESLineSearchSetFromOptions(SNESLineSearch);
541 PETSC_EXTERN PetscErrorCode SNESLineSearchSetUp(SNESLineSearch);
542 PETSC_EXTERN PetscErrorCode SNESLineSearchApply(SNESLineSearch, Vec, Vec, PetscReal *, Vec);
543 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheck(SNESLineSearch,Vec,Vec,PetscBool *);
544 PETSC_EXTERN PetscErrorCode SNESLineSearchPostCheck(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *);
545 PETSC_EXTERN PetscErrorCode SNESLineSearchGetWork(SNESLineSearch, PetscInt);
546 
547 /* set the functions for precheck and postcheck */
548 
549 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPreCheck(SNESLineSearch, PetscErrorCode (*SNESLineSearchPreCheckFunction)(SNESLineSearch,Vec,Vec,PetscBool*,void*), void *ctx);
550 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPostCheck(SNESLineSearch, PetscErrorCode (*SNESLineSearchPostCheckFunction)(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *,void*), void *ctx);
551 
552 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPreCheck(SNESLineSearch, PetscErrorCode (**SNESLineSearchPreCheckFunction)(SNESLineSearch,Vec,Vec,PetscBool*,void*), void **ctx);
553 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPostCheck(SNESLineSearch, PetscErrorCode (**SNESLineSearchPostCheckFunction)(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *,void*), void **ctx);
554 
555 /* set the functions for VI-specific line search operations */
556 
557 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc, SNESLineSearchVINormFunc);
558 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc*, SNESLineSearchVINormFunc*);
559 
560 /* pointers to the associated SNES in order to be able to get the function evaluation out */
561 PETSC_EXTERN PetscErrorCode SNESLineSearchSetSNES(SNESLineSearch,SNES);
562 PETSC_EXTERN PetscErrorCode SNESLineSearchGetSNES(SNESLineSearch,SNES*);
563 
564 /* set and get the parameters and vectors */
565 PETSC_EXTERN PetscErrorCode SNESLineSearchGetTolerances(SNESLineSearch,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscInt*);
566 PETSC_EXTERN PetscErrorCode SNESLineSearchSetTolerances(SNESLineSearch,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscInt);
567 
568 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheckPicard(SNESLineSearch,Vec,Vec,PetscBool*,void*);
569 
570 PETSC_EXTERN PetscErrorCode SNESLineSearchGetLambda(SNESLineSearch,PetscReal*);
571 PETSC_EXTERN PetscErrorCode SNESLineSearchSetLambda(SNESLineSearch,PetscReal);
572 
573 PETSC_EXTERN PetscErrorCode SNESLineSearchGetDamping(SNESLineSearch,PetscReal*);
574 PETSC_EXTERN PetscErrorCode SNESLineSearchSetDamping(SNESLineSearch,PetscReal);
575 
576 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOrder(SNESLineSearch,PetscInt *order);
577 PETSC_EXTERN PetscErrorCode SNESLineSearchSetOrder(SNESLineSearch,PetscInt order);
578 
579 PETSC_EXTERN PetscErrorCode SNESLineSearchGetSuccess(SNESLineSearch, PetscBool*);
580 PETSC_EXTERN PetscErrorCode SNESLineSearchSetSuccess(SNESLineSearch, PetscBool);
581 
582 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVecs(SNESLineSearch,Vec*,Vec*,Vec*,Vec*,Vec*);
583 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVecs(SNESLineSearch,Vec,Vec,Vec,Vec,Vec);
584 
585 PETSC_EXTERN PetscErrorCode SNESLineSearchGetNorms(SNESLineSearch, PetscReal *, PetscReal *, PetscReal *);
586 PETSC_EXTERN PetscErrorCode SNESLineSearchSetNorms(SNESLineSearch, PetscReal, PetscReal, PetscReal);
587 PETSC_EXTERN PetscErrorCode SNESLineSearchComputeNorms(SNESLineSearch);
588 PETSC_EXTERN PetscErrorCode SNESLineSearchSetComputeNorms(SNESLineSearch, PetscBool);
589 
590 PETSC_EXTERN PetscErrorCode SNESLineSearchSetMonitor(SNESLineSearch, PetscBool);
591 PETSC_EXTERN PetscErrorCode SNESLineSearchGetMonitor(SNESLineSearch, PetscViewer*);
592 
593 PETSC_EXTERN PetscErrorCode SNESLineSearchAppendOptionsPrefix(SNESLineSearch, const char prefix[]);
594 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOptionsPrefix(SNESLineSearch, const char *prefix[]);
595 
596 
597 /* Shell interface functions */
598 PETSC_EXTERN PetscErrorCode SNESLineSearchShellSetUserFunc(SNESLineSearch,SNESLineSearchUserFunc,void*);
599 PETSC_EXTERN PetscErrorCode SNESLineSearchShellGetUserFunc(SNESLineSearch,SNESLineSearchUserFunc*,void**);
600 
601 /* BT interface functions */
602 PETSC_EXTERN PetscErrorCode SNESLineSearchBTSetAlpha(SNESLineSearch, PetscReal);
603 PETSC_EXTERN PetscErrorCode SNESLineSearchBTGetAlpha(SNESLineSearch, PetscReal*);
604 
605 /*register line search types */
606 PETSC_EXTERN PetscErrorCode SNESLineSearchRegister(const char[],const char[],const char[],PetscErrorCode(*)(SNESLineSearch));
607 PETSC_EXTERN PetscErrorCode SNESLineSearchRegisterAll(const char path[]);
608 PETSC_EXTERN PetscErrorCode SNESLineSearchRegisterDestroy(void);
609 
610 #if defined(PETSC_USE_DYNAMIC_LIBRARIES)
611 #define SNESLineSearchRegisterDynamic(a,b,c,d) SNESLineSearchRegister(a,b,c,0)
612 #else
613 #define SNESLineSearchRegisterDynamic(a,b,c,d) SNESLineSearchRegister(a,b,c,d)
614 #endif
615 
616 /* Routines for VI solver */
617 PETSC_EXTERN PetscErrorCode SNESVISetVariableBounds(SNES,Vec,Vec);
618 PETSC_EXTERN PetscErrorCode SNESVISetComputeVariableBounds(SNES, PetscErrorCode (*)(SNES,Vec,Vec));
619 PETSC_EXTERN PetscErrorCode SNESVIGetInactiveSet(SNES,IS*);
620 PETSC_EXTERN PetscErrorCode SNESVIGetActiveSetIS(SNES,Vec,Vec,IS*);
621 PETSC_EXTERN PetscErrorCode SNESVIComputeInactiveSetFnorm(SNES,Vec,Vec,PetscReal*);
622 PETSC_EXTERN PetscErrorCode SNESVISetRedundancyCheck(SNES,PetscErrorCode(*)(SNES,IS,IS*,void*),void*);
623 #define SNES_VI_INF   1.0e20
624 #define SNES_VI_NINF -1.0e20
625 
626 PETSC_EXTERN PetscErrorCode SNESTestLocalMin(SNES);
627 
628 /* Should this routine be private? */
629 PETSC_EXTERN PetscErrorCode SNESComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*);
630 
631 PETSC_EXTERN PetscErrorCode SNESSetDM(SNES,DM);
632 PETSC_EXTERN PetscErrorCode SNESGetDM(SNES,DM*);
633 PETSC_EXTERN PetscErrorCode SNESSetPC(SNES,SNES);
634 PETSC_EXTERN PetscErrorCode SNESGetPC(SNES,SNES*);
635 PETSC_EXTERN PetscErrorCode SNESSetPCSide(SNES,PCSide);
636 PETSC_EXTERN PetscErrorCode SNESGetPCSide(SNES,PCSide*);
637 PETSC_EXTERN PetscErrorCode SNESSetSNESLineSearch(SNES,SNESLineSearch);
638 PETSC_EXTERN PetscErrorCode SNESGetSNESLineSearch(SNES,SNESLineSearch*);
639 PETSC_EXTERN PetscErrorCode SNESRestrictHookAdd(SNES,PetscErrorCode (*)(SNES,SNES,void*),void*);
640 PETSC_EXTERN PetscErrorCode SNESRestrictHooksRun(SNES,SNES);
641 
642 PETSC_EXTERN PetscErrorCode SNESSetUpMatrices(SNES);
643 PETSC_EXTERN PetscErrorCode DMSNESSetFunction(DM,PetscErrorCode(*SNESFunction)(SNES,Vec,Vec,void*),void*);
644 PETSC_EXTERN PetscErrorCode DMSNESGetFunction(DM,PetscErrorCode(**SNESSetFunction)(SNES,Vec,Vec,void*),void**);
645 PETSC_EXTERN PetscErrorCode DMSNESSetGS(DM,PetscErrorCode(*SNESGSFunction)(SNES,Vec,Vec,void*),void*);
646 PETSC_EXTERN PetscErrorCode DMSNESGetGS(DM,PetscErrorCode(**SNESGSFunction)(SNES,Vec,Vec,void*),void**);
647 PETSC_EXTERN PetscErrorCode DMSNESSetJacobian(DM,PetscErrorCode(*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
648 PETSC_EXTERN PetscErrorCode DMSNESGetJacobian(DM,PetscErrorCode(**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
649 PETSC_EXTERN PetscErrorCode DMSNESSetPicard(DM,PetscErrorCode(*SNESFunction)(SNES,Vec,Vec,void*),PetscErrorCode(*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
650 PETSC_EXTERN PetscErrorCode DMSNESGetPicard(DM,PetscErrorCode(**SNESFunction)(SNES,Vec,Vec,void*),PetscErrorCode(**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
651 PETSC_EXTERN PetscErrorCode DMSNESSetObjective(DM,PetscErrorCode (*SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void*);
652 PETSC_EXTERN PetscErrorCode DMSNESGetObjective(DM,PetscErrorCode (**SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void**);
653 
654 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESFunction)(DMDALocalInfo*,void*,void*,void*);
655 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESJacobian)(DMDALocalInfo*,void*,Mat,Mat,MatStructure*,void*);
656 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESObjective)(DMDALocalInfo*,void*,PetscReal*,void*);
657 
658 PETSC_EXTERN PetscErrorCode DMDASNESSetFunctionLocal(DM,InsertMode,DMDASNESFunction,void*);
659 PETSC_EXTERN PetscErrorCode DMDASNESSetJacobianLocal(DM,DMDASNESJacobian,void*);
660 PETSC_EXTERN PetscErrorCode DMDASNESSetObjectiveLocal(DM,DMDASNESObjective,void*);
661 PETSC_EXTERN PetscErrorCode DMDASNESSetPicardLocal(DM,InsertMode,PetscErrorCode (*)(DMDALocalInfo*,void*,void*,void*),PetscErrorCode (*)(DMDALocalInfo*,void*,Mat,Mat,MatStructure*,void*),void*);
662 
663 PETSC_EXTERN PetscErrorCode DMSNESSetFunctionLocal(DM,PetscErrorCode (*)(DM,Vec,Vec,void*),void*);
664 PETSC_EXTERN PetscErrorCode DMSNESSetJacobianLocal(DM,PetscErrorCode (*)(DM,Vec,Mat,Mat,MatStructure*,void*),void*);
665 
666 /* Routines for Multiblock solver */
667 PETSC_EXTERN PetscErrorCode SNESMultiblockSetFields(SNES, const char [], PetscInt, const PetscInt *);
668 PETSC_EXTERN PetscErrorCode SNESMultiblockSetIS(SNES, const char [], IS);
669 PETSC_EXTERN PetscErrorCode SNESMultiblockSetBlockSize(SNES, PetscInt);
670 PETSC_EXTERN PetscErrorCode SNESMultiblockSetType(SNES, PCCompositeType);
671 
672 /*J
673     SNESMSType - String with the name of a PETSc SNESMS method.
674 
675    Level: intermediate
676 
677 .seealso: SNESMSSetType(), SNES
678 J*/
679 typedef const char* SNESMSType;
680 #define SNESMSM62       "m62"
681 #define SNESMSEULER     "euler"
682 #define SNESMSJAMESON83 "jameson83"
683 #define SNESMSVLTP21    "vltp21"
684 #define SNESMSVLTP31    "vltp31"
685 #define SNESMSVLTP41    "vltp41"
686 #define SNESMSVLTP51    "vltp51"
687 #define SNESMSVLTP61    "vltp61"
688 
689 PETSC_EXTERN PetscErrorCode SNESMSRegister(SNESMSType,PetscInt,PetscInt,PetscReal,const PetscReal[],const PetscReal[],const PetscReal[]);
690 PETSC_EXTERN PetscErrorCode SNESMSSetType(SNES,SNESMSType);
691 PETSC_EXTERN PetscErrorCode SNESMSFinalizePackage(void);
692 PETSC_EXTERN PetscErrorCode SNESMSInitializePackage(const char path[]);
693 PETSC_EXTERN PetscErrorCode SNESMSRegisterDestroy(void);
694 PETSC_EXTERN PetscErrorCode SNESMSRegisterAll(void);
695 
696 /* routines for NGMRES solver */
697 
698 typedef enum {
699   SNES_NGMRES_RESTART_NONE       = 0,
700   SNES_NGMRES_RESTART_PERIODIC   = 1,
701   SNES_NGMRES_RESTART_DIFFERENCE = 2} SNESNGMRESRestartType;
702 PETSC_EXTERN const char *const SNESNGMRESRestartTypes[];
703 
704 typedef enum {
705   SNES_NGMRES_SELECT_NONE       = 0,
706   SNES_NGMRES_SELECT_DIFFERENCE = 1,
707   SNES_NGMRES_SELECT_LINESEARCH = 2} SNESNGMRESSelectType;
708 PETSC_EXTERN const char *const SNESNGMRESSelectTypes[];
709 
710 PETSC_EXTERN PetscErrorCode SNESNGMRESSetRestartType(SNES, SNESNGMRESRestartType);
711 PETSC_EXTERN PetscErrorCode SNESNGMRESSetSelectType(SNES, SNESNGMRESSelectType);
712 
713 /* routines for NCG solver */
714 
715 typedef enum {
716   SNES_NCG_FR    = 0,
717   SNES_NCG_PRP   = 1,
718   SNES_NCG_HS    = 2,
719   SNES_NCG_DY    = 3,
720   SNES_NCG_CD    = 4} SNESNCGType;
721 PETSC_EXTERN const char *const SNESNCGTypes[];
722 
723 PETSC_EXTERN PetscErrorCode SNESNCGSetType(SNES, SNESNCGType);
724 
725 typedef enum {SNES_QN_SCALE_NONE       = 0,
726               SNES_QN_SCALE_SHANNO     = 1,
727               SNES_QN_SCALE_LINESEARCH = 2,
728               SNES_QN_SCALE_JACOBIAN   = 3} SNESQNScaleType;
729 PETSC_EXTERN const char *const SNESQNScaleTypes[];
730 typedef enum {SNES_QN_RESTART_NONE     = 0,
731               SNES_QN_RESTART_POWELL   = 1,
732               SNES_QN_RESTART_PERIODIC = 2} SNESQNRestartType;
733 PETSC_EXTERN const char *const SNESQNRestartTypes[];
734 
735 PETSC_EXTERN PetscErrorCode SNESQNSetScaleType(SNES, SNESQNScaleType);
736 PETSC_EXTERN PetscErrorCode SNESQNSetRestartType(SNES, SNESQNRestartType);
737 
738 
739 #endif
740