xref: /petsc/include/petscsnes.h (revision b6bfaf9a0a178e626c17e7b8aafd5e3bedcd9a6d)
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 #define SNESANDERSON     "anderson"
47 
48 /* Logging support */
49 PETSC_EXTERN PetscClassId SNES_CLASSID;
50 PETSC_EXTERN PetscClassId DMSNES_CLASSID;
51 
52 PETSC_EXTERN PetscErrorCode SNESInitializePackage(const char[]);
53 
54 PETSC_EXTERN PetscErrorCode SNESCreate(MPI_Comm,SNES*);
55 PETSC_EXTERN PetscErrorCode SNESReset(SNES);
56 PETSC_EXTERN PetscErrorCode SNESDestroy(SNES*);
57 PETSC_EXTERN PetscErrorCode SNESSetType(SNES,SNESType);
58 PETSC_EXTERN PetscErrorCode SNESMonitor(SNES,PetscInt,PetscReal);
59 PETSC_EXTERN PetscErrorCode SNESMonitorSet(SNES,PetscErrorCode(*)(SNES,PetscInt,PetscReal,void*),void *,PetscErrorCode (*)(void**));
60 PETSC_EXTERN PetscErrorCode SNESMonitorCancel(SNES);
61 PETSC_EXTERN PetscErrorCode SNESSetConvergenceHistory(SNES,PetscReal[],PetscInt[],PetscInt,PetscBool );
62 PETSC_EXTERN PetscErrorCode SNESGetConvergenceHistory(SNES,PetscReal*[],PetscInt *[],PetscInt *);
63 PETSC_EXTERN PetscErrorCode SNESSetUp(SNES);
64 PETSC_EXTERN PetscErrorCode SNESSolve(SNES,Vec,Vec);
65 PETSC_EXTERN PetscErrorCode SNESSetErrorIfNotConverged(SNES,PetscBool );
66 PETSC_EXTERN PetscErrorCode SNESGetErrorIfNotConverged(SNES,PetscBool  *);
67 
68 
69 PETSC_EXTERN PetscErrorCode SNESAddOptionsChecker(PetscErrorCode (*)(SNES));
70 
71 PETSC_EXTERN PetscErrorCode SNESSetUpdate(SNES, PetscErrorCode (*)(SNES, PetscInt));
72 PETSC_EXTERN PetscErrorCode SNESDefaultUpdate(SNES, PetscInt);
73 
74 PETSC_EXTERN PetscErrorCode SNESRegisterDestroy(void);
75 PETSC_EXTERN PetscErrorCode SNESRegisterAll(const char[]);
76 
77 PETSC_EXTERN PetscErrorCode SNESRegister(const char[],const char[],const char[],PetscErrorCode (*)(SNES));
78 
79 /*MC
80    SNESRegisterDynamic - Adds a method to the nonlinear solver package.
81 
82    Synopsis:
83     #include "petscsnes.h"
84    PetscErrorCode SNESRegisterDynamic(const char *name_solver,const char *path,const char *name_create,PetscErrorCode (*routine_create)(SNES))
85 
86    Not collective
87 
88    Input Parameters:
89 +  name_solver - name of a new user-defined solver
90 .  path - path (either absolute or relative) the library containing this solver
91 .  name_create - name of routine to create method context
92 -  routine_create - routine to create method context
93 
94    Notes:
95    SNESRegisterDynamic() may be called multiple times to add several user-defined solvers.
96 
97    If dynamic libraries are used, then the fourth input argument (routine_create)
98    is ignored.
99 
100    Environmental variables such as ${PETSC_ARCH}, ${PETSC_DIR}, ${PETSC_LIB_DIR},
101    and others of the form ${any_environmental_variable} occuring in pathname will be
102    replaced with appropriate values.
103 
104    Sample usage:
105 .vb
106    SNESRegisterDynamic("my_solver",/home/username/my_lib/lib/libg/solaris/mylib.a,
107                 "MySolverCreate",MySolverCreate);
108 .ve
109 
110    Then, your solver can be chosen with the procedural interface via
111 $     SNESSetType(snes,"my_solver")
112    or at runtime via the option
113 $     -snes_type my_solver
114 
115    Level: advanced
116 
117     Note: If your function is not being put into a shared library then use SNESRegister() instead
118 
119 .keywords: SNES, nonlinear, register
120 
121 .seealso: SNESRegisterAll(), SNESRegisterDestroy()
122 M*/
123 #if defined(PETSC_USE_DYNAMIC_LIBRARIES)
124 #define SNESRegisterDynamic(a,b,c,d) SNESRegister(a,b,c,0)
125 #else
126 #define SNESRegisterDynamic(a,b,c,d) SNESRegister(a,b,c,d)
127 #endif
128 
129 PETSC_EXTERN PetscErrorCode SNESGetKSP(SNES,KSP*);
130 PETSC_EXTERN PetscErrorCode SNESSetKSP(SNES,KSP);
131 PETSC_EXTERN PetscErrorCode SNESGetSolution(SNES,Vec*);
132 PETSC_EXTERN PetscErrorCode SNESGetSolutionUpdate(SNES,Vec*);
133 PETSC_EXTERN PetscErrorCode SNESGetRhs(SNES,Vec*);
134 PETSC_EXTERN PetscErrorCode SNESView(SNES,PetscViewer);
135 PETSC_EXTERN PetscErrorCode SNESLoad(SNES,PetscViewer);
136 
137 #define SNES_FILE_CLASSID 1211224
138 
139 PETSC_EXTERN PetscErrorCode SNESSetOptionsPrefix(SNES,const char[]);
140 PETSC_EXTERN PetscErrorCode SNESAppendOptionsPrefix(SNES,const char[]);
141 PETSC_EXTERN PetscErrorCode SNESGetOptionsPrefix(SNES,const char*[]);
142 PETSC_EXTERN PetscErrorCode SNESSetFromOptions(SNES);
143 PETSC_EXTERN PetscErrorCode SNESDefaultGetWork(SNES,PetscInt);
144 
145 PETSC_EXTERN PetscErrorCode MatCreateSNESMF(SNES,Mat*);
146 PETSC_EXTERN PetscErrorCode MatMFFDComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
147 
148 PETSC_EXTERN PetscErrorCode MatDAADSetSNES(Mat,SNES);
149 
150 PETSC_EXTERN PetscErrorCode SNESGetType(SNES,SNESType*);
151 PETSC_EXTERN PetscErrorCode SNESMonitorDefault(SNES,PetscInt,PetscReal,void *);
152 PETSC_EXTERN PetscErrorCode SNESMonitorRange(SNES,PetscInt,PetscReal,void *);
153 PETSC_EXTERN PetscErrorCode SNESMonitorRatio(SNES,PetscInt,PetscReal,void *);
154 PETSC_EXTERN PetscErrorCode SNESMonitorSetRatio(SNES,PetscViewer);
155 PETSC_EXTERN PetscErrorCode SNESMonitorSolution(SNES,PetscInt,PetscReal,void *);
156 PETSC_EXTERN PetscErrorCode SNESMonitorResidual(SNES,PetscInt,PetscReal,void *);
157 PETSC_EXTERN PetscErrorCode SNESMonitorSolutionUpdate(SNES,PetscInt,PetscReal,void *);
158 PETSC_EXTERN PetscErrorCode SNESMonitorDefaultShort(SNES,PetscInt,PetscReal,void *);
159 PETSC_EXTERN PetscErrorCode SNESMonitorJacUpdateSpectrum(SNES,PetscInt,PetscReal,void *);
160 PETSC_EXTERN PetscErrorCode SNESSetTolerances(SNES,PetscReal,PetscReal,PetscReal,PetscInt,PetscInt);
161 PETSC_EXTERN PetscErrorCode SNESGetTolerances(SNES,PetscReal*,PetscReal*,PetscReal*,PetscInt*,PetscInt*);
162 PETSC_EXTERN PetscErrorCode SNESSetTrustRegionTolerance(SNES,PetscReal);
163 PETSC_EXTERN PetscErrorCode SNESGetFunctionNorm(SNES,PetscReal*);
164 PETSC_EXTERN PetscErrorCode SNESSetFunctionNorm(SNES,PetscReal);
165 PETSC_EXTERN PetscErrorCode SNESGetIterationNumber(SNES,PetscInt*);
166 PETSC_EXTERN PetscErrorCode SNESSetIterationNumber(SNES,PetscInt);
167 
168 PETSC_EXTERN PetscErrorCode SNESGetNonlinearStepFailures(SNES,PetscInt*);
169 PETSC_EXTERN PetscErrorCode SNESSetMaxNonlinearStepFailures(SNES,PetscInt);
170 PETSC_EXTERN PetscErrorCode SNESGetMaxNonlinearStepFailures(SNES,PetscInt*);
171 PETSC_EXTERN PetscErrorCode SNESGetNumberFunctionEvals(SNES,PetscInt*);
172 
173 PETSC_EXTERN PetscErrorCode SNESSetLagPreconditioner(SNES,PetscInt);
174 PETSC_EXTERN PetscErrorCode SNESGetLagPreconditioner(SNES,PetscInt*);
175 PETSC_EXTERN PetscErrorCode SNESSetLagJacobian(SNES,PetscInt);
176 PETSC_EXTERN PetscErrorCode SNESGetLagJacobian(SNES,PetscInt*);
177 PETSC_EXTERN PetscErrorCode SNESSetGridSequence(SNES,PetscInt);
178 
179 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveIterations(SNES,PetscInt*);
180 PETSC_EXTERN PetscErrorCode SNESGetLinearSolveFailures(SNES,PetscInt*);
181 PETSC_EXTERN PetscErrorCode SNESSetMaxLinearSolveFailures(SNES,PetscInt);
182 PETSC_EXTERN PetscErrorCode SNESGetMaxLinearSolveFailures(SNES,PetscInt*);
183 
184 PETSC_EXTERN PetscErrorCode SNESKSPSetUseEW(SNES,PetscBool );
185 PETSC_EXTERN PetscErrorCode SNESKSPGetUseEW(SNES,PetscBool *);
186 PETSC_EXTERN PetscErrorCode SNESKSPSetParametersEW(SNES,PetscInt,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal);
187 PETSC_EXTERN PetscErrorCode SNESKSPGetParametersEW(SNES,PetscInt*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*);
188 
189 PETSC_EXTERN PetscErrorCode SNESMonitorLGCreate(const char[],const char[],int,int,int,int,PetscDrawLG*);
190 PETSC_EXTERN PetscErrorCode SNESMonitorLGResidualNorm(SNES,PetscInt,PetscReal,void*);
191 PETSC_EXTERN PetscErrorCode SNESMonitorLGDestroy(PetscDrawLG*);
192 PETSC_EXTERN PetscErrorCode SNESMonitorLGRange(SNES,PetscInt,PetscReal,void*);
193 
194 PETSC_EXTERN PetscErrorCode SNESSetApplicationContext(SNES,void *);
195 PETSC_EXTERN PetscErrorCode SNESGetApplicationContext(SNES,void *);
196 PETSC_EXTERN PetscErrorCode SNESSetComputeApplicationContext(SNES,PetscErrorCode (*)(SNES,void**),PetscErrorCode (*)(void**));
197 
198 PETSC_EXTERN PetscErrorCode SNESPythonSetType(SNES,const char[]);
199 
200 PETSC_EXTERN PetscErrorCode SNESSetFunctionDomainError(SNES);
201 PETSC_EXTERN PetscErrorCode SNESGetFunctionDomainError(SNES, PetscBool *);
202 
203 /*E
204     SNESConvergedReason - reason a SNES method was said to
205          have converged or diverged
206 
207    Level: beginner
208 
209    The two most common reasons for divergence are
210 $   1) an incorrectly coded or computed Jacobian or
211 $   2) failure or lack of convergence in the linear system (in this case we recommend
212 $      testing with -pc_type lu to eliminate the linear solver as the cause of the problem).
213 
214    Diverged Reasons:
215 .    SNES_DIVERGED_LOCAL_MIN - this can only occur when using the line-search variant of SNES.
216        The line search wants to minimize Q(alpha) = 1/2 || F(x + alpha s) ||^2_2  this occurs
217        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
218        you get Q'(alpha) = -F(x)^T F'(x)^(-1)^T F'(x+alpha s)F(x+alpha s); when alpha = 0
219        Q'(0) = - ||F(x)||^2_2 which is always NEGATIVE if F'(x) is invertible. This means the Newton
220        direction is a descent direction and the line search should succeed if alpha is small enough.
221 
222        If F'(x) is NOT invertible AND F'(x)^T F(x) = 0 then Q'(0) = 0 and the Newton direction
223        is NOT a descent direction so the line search will fail. All one can do at this point
224        is change the initial guess and try again.
225 
226        An alternative explanation: Newton's method can be regarded as replacing the function with
227        its linear approximation and minimizing the 2-norm of that. That is F(x+s) approx F(x) + F'(x)s
228        so we minimize || F(x) + F'(x) s ||^2_2; do this using Least Squares. If F'(x) is invertible then
229        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
230        exists a nontrival (that is F'(x)s != 0) solution to the equation and this direction is
231        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)
232        = - (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
233        and F'(x)^T F'(x) has no negative eigenvalues Q'(0) < 0 so s is a descent direction and the line
234        search should succeed for small enough alpha.
235 
236        Note that this RARELY happens in practice. Far more likely the linear system is not being solved
237        (well enough?) or the Jacobian is wrong.
238 
239    SNES_DIVERGED_MAX_IT means that the solver reached the maximum number of iterations without satisfying any
240    convergence criteria. SNES_CONVERGED_ITS means that SNESSkipConverged() was chosen as the convergence test;
241    thus the usual convergence criteria have not been checked and may or may not be satisfied.
242 
243    Developer Notes: this must match finclude/petscsnes.h
244 
245        The string versions of these are in SNESConvergedReason, if you change any value here you must
246      also adjust that array.
247 
248    Each reason has its own manual page.
249 
250 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPConvergedReason, SNESSetConvergenceTest()
251 E*/
252 typedef enum {/* converged */
253               SNES_CONVERGED_FNORM_ABS         =  2, /* ||F|| < atol */
254               SNES_CONVERGED_FNORM_RELATIVE    =  3, /* ||F|| < rtol*||F_initial|| */
255               SNES_CONVERGED_SNORM_RELATIVE    =  4, /* Newton computed step size small; || delta x || < stol || x ||*/
256               SNES_CONVERGED_ITS               =  5, /* maximum iterations reached */
257               SNES_CONVERGED_TR_DELTA          =  7,
258               /* diverged */
259               SNES_DIVERGED_FUNCTION_DOMAIN     = -1, /* the new x location passed the function is not in the domain of F */
260               SNES_DIVERGED_FUNCTION_COUNT      = -2,
261               SNES_DIVERGED_LINEAR_SOLVE        = -3, /* the linear solve failed */
262               SNES_DIVERGED_FNORM_NAN           = -4,
263               SNES_DIVERGED_MAX_IT              = -5,
264               SNES_DIVERGED_LINE_SEARCH         = -6, /* the line search failed */
265               SNES_DIVERGED_INNER               = -7, /* inner solve failed */
266               SNES_DIVERGED_LOCAL_MIN           = -8, /* || J^T b || is small, implies converged to local minimum of F() */
267               SNES_CONVERGED_ITERATING          =  0} SNESConvergedReason;
268 PETSC_EXTERN const char *const*SNESConvergedReasons;
269 
270 /*MC
271      SNES_CONVERGED_FNORM_ABS - 2-norm(F) <= abstol
272 
273    Level: beginner
274 
275 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
276 
277 M*/
278 
279 /*MC
280      SNES_CONVERGED_FNORM_RELATIVE - 2-norm(F) <= rtol*2-norm(F(x_0)) where x_0 is the initial guess
281 
282    Level: beginner
283 
284 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
285 
286 M*/
287 
288 /*MC
289      SNES_CONVERGED_SNORM_RELATIVE - The 2-norm of the last step <= stol * 2-norm(x) where x is the current
290           solution and stol is the 4th argument to SNESSetTolerances()
291 
292      Options Database Keys:
293       -snes_stol <stol> - the step tolerance
294 
295    Level: beginner
296 
297 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
298 
299 M*/
300 
301 /*MC
302      SNES_DIVERGED_FUNCTION_COUNT - The user provided function has been called more times then the final
303          argument to SNESSetTolerances()
304 
305    Level: beginner
306 
307 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
308 
309 M*/
310 
311 /*MC
312      SNES_DIVERGED_FNORM_NAN - the 2-norm of the current function evaluation is not-a-number (NaN), this
313       is usually caused by a division of 0 by 0.
314 
315    Level: beginner
316 
317 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
318 
319 M*/
320 
321 /*MC
322      SNES_DIVERGED_MAX_IT - SNESSolve() has reached the maximum number of iterations requested
323 
324    Level: beginner
325 
326 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
327 
328 M*/
329 
330 /*MC
331      SNES_DIVERGED_LINE_SEARCH - The line search has failed. This only occurs for a SNES solvers that use a line search
332 
333    Level: beginner
334 
335 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances(), SNESLineSearch
336 
337 M*/
338 
339 /*MC
340      SNES_DIVERGED_LOCAL_MIN - the algorithm seems to have stagnated at a local minimum that is not zero.
341         See the manual page for SNESConvergedReason for more details
342 
343    Level: beginner
344 
345 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
346 
347 M*/
348 
349 /*MC
350      SNES_CONERGED_ITERATING - this only occurs if SNESGetConvergedReason() is called during the SNESSolve()
351 
352    Level: beginner
353 
354 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
355 
356 M*/
357 
358 PETSC_EXTERN PetscErrorCode SNESSetConvergenceTest(SNES,PetscErrorCode (*)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*),void*,PetscErrorCode (*)(void*));
359 PETSC_EXTERN PetscErrorCode SNESDefaultConverged(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
360 PETSC_EXTERN PetscErrorCode SNESSkipConverged(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
361 PETSC_EXTERN PetscErrorCode SNESGetConvergedReason(SNES,SNESConvergedReason*);
362 
363 PETSC_EXTERN PetscErrorCode SNESDMMeshComputeFunction(SNES,Vec,Vec,void*);
364 PETSC_EXTERN PetscErrorCode SNESDMMeshComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
365 
366 /* --------- Solving systems of nonlinear equations --------------- */
367 PETSC_EXTERN PetscErrorCode SNESSetFunction(SNES,Vec,PetscErrorCode (*SNESFunction)(SNES,Vec,Vec,void*),void*);
368 PETSC_EXTERN PetscErrorCode SNESGetFunction(SNES,Vec*,PetscErrorCode (**SNESFunction)(SNES,Vec,Vec,void*),void**);
369 PETSC_EXTERN PetscErrorCode SNESComputeFunction(SNES,Vec,Vec);
370 PETSC_EXTERN PetscErrorCode SNESSetJacobian(SNES,Mat,Mat,PetscErrorCode (*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
371 PETSC_EXTERN PetscErrorCode SNESGetJacobian(SNES,Mat*,Mat*,PetscErrorCode (**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
372 PETSC_EXTERN PetscErrorCode SNESDefaultObjectiveComputeFunctionFD(SNES,Vec,Vec,void*);
373 PETSC_EXTERN PetscErrorCode SNESDefaultComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
374 PETSC_EXTERN PetscErrorCode SNESDefaultComputeJacobianColor(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
375 PETSC_EXTERN PetscErrorCode SNESSetComputeInitialGuess(SNES,PetscErrorCode (*)(SNES,Vec,void*),void*);
376 PETSC_EXTERN PetscErrorCode SNESSetPicard(SNES,Vec,PetscErrorCode (*SNESFunction)(SNES,Vec,Vec,void*),Mat,Mat,PetscErrorCode (*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
377 PETSC_EXTERN PetscErrorCode SNESGetPicard(SNES,Vec*,PetscErrorCode (**SNESFunction)(SNES,Vec,Vec,void*),Mat*,Mat*,PetscErrorCode (**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
378 PETSC_EXTERN PetscErrorCode SNESSetInitialFunction(SNES,Vec);
379 PETSC_EXTERN PetscErrorCode SNESSetInitialFunctionNorm(SNES,PetscReal);
380 
381 PETSC_EXTERN PetscErrorCode SNESSetObjective(SNES,PetscErrorCode (*SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void*);
382 PETSC_EXTERN PetscErrorCode SNESGetObjective(SNES,PetscErrorCode (**SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void**);
383 PETSC_EXTERN PetscErrorCode SNESComputeObjective(SNES,Vec,PetscReal *);
384 
385 /*E
386     SNESNormType - Norm that is passed in the Krylov convergence
387        test routines.
388 
389    Level: advanced
390 
391    Support for these is highly dependent on the solver.
392 
393    Notes:
394    This is primarily used to turn off extra norm and function computation
395    when the solvers are composed.
396 
397 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPSetNormType(),
398           KSPSetConvergenceTest(), KSPSetPCSide()
399 E*/
400 
401 typedef enum {SNES_NORM_DEFAULT            = -1,
402               SNES_NORM_NONE               =  0,
403               SNES_NORM_FUNCTION           =  1,
404               SNES_NORM_INITIAL_ONLY       =  2,
405               SNES_NORM_FINAL_ONLY         =  3,
406               SNES_NORM_INITIAL_FINAL_ONLY =  4} SNESNormType;
407 PETSC_EXTERN const char *const*const SNESNormTypes;
408 /*MC
409     SNES_NORM_NONE - Don't compute function and its L2 norm.
410 
411    Level: advanced
412 
413     Notes:
414     This is most useful for stationary solvers with a fixed number of iterations used as smoothers.
415 
416 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_DEFAULT
417 M*/
418 
419 /*MC
420     SNES_NORM_FUNCTION - Compute the function and its L2 norm at each iteration.
421 
422    Level: advanced
423 
424     Notes:
425     Most solvers will use this no matter what norm type is passed to them.
426 
427 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_NONE
428 M*/
429 
430 /*MC
431     SNES_NORM_INITIAL_ONLY - Compute the function and its L2 at iteration 0, but do not update it.
432 
433    Level: advanced
434 
435    Notes:
436    This method is useful in composed methods, when a true solution might actually be found before SNESSolve() is called.
437    This option enables the solve to abort on the zeroth iteration if this is the case.
438 
439    For solvers that require the computation of the L2 norm of the function as part of the method, this merely cancels
440    the norm computation at the last iteration (if possible).
441 
442 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_FINAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
443 M*/
444 
445 /*MC
446     SNES_NORM_FINAL_ONLY - Compute the function and its L2 norm on only the final iteration.
447 
448    Level: advanced
449 
450    Notes:
451    For solvers that require the computation of the L2 norm of the function as part of the method, behaves
452    exactly as SNES_NORM_DEFAULT.  This method is useful when the function is gotten after SNESSolve and
453    used in subsequent computation for methods that do not need the norm computed during the rest of the
454    solution procedure.
455 
456 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_INITIAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
457 M*/
458 
459 /*MC
460     SNES_NORM_INITIAL_FINAL_ONLY - Compute the function and its L2 norm on only the initial and final iterations.
461 
462    Level: advanced
463 
464    Notes:
465    This method combines the benefits of SNES_NORM_INITIAL_ONLY and SNES_NORM_FINAL_ONLY.
466 
467 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_SNES_NORM_INITIAL_ONLY, SNES_NORM_FINAL_ONLY
468 M*/
469 
470 
471 PETSC_EXTERN PetscErrorCode SNESSetNormType(SNES,SNESNormType);
472 PETSC_EXTERN PetscErrorCode SNESGetNormType(SNES,SNESNormType*);
473 
474 PETSC_EXTERN PetscErrorCode SNESSetGS(SNES,PetscErrorCode (*SNESGSFunction)(SNES,Vec,Vec,void*),void*);
475 PETSC_EXTERN PetscErrorCode SNESGetGS(SNES,PetscErrorCode (**SNESGSFunction)(SNES,Vec,Vec,void*),void**);
476 PETSC_EXTERN PetscErrorCode SNESSetUseGS(SNES,PetscBool);
477 PETSC_EXTERN PetscErrorCode SNESGetUseGS(SNES,PetscBool *);
478 PETSC_EXTERN PetscErrorCode SNESComputeGS(SNES,Vec,Vec);
479 
480 PETSC_EXTERN PetscErrorCode SNESGSSetSweeps(SNES,PetscInt);
481 PETSC_EXTERN PetscErrorCode SNESGSGetSweeps(SNES,PetscInt *);
482 PETSC_EXTERN PetscErrorCode SNESGSSetTolerances(SNES,PetscReal,PetscReal,PetscReal,PetscInt);
483 PETSC_EXTERN PetscErrorCode SNESGSGetTolerances(SNES,PetscReal*,PetscReal*,PetscReal*,PetscInt*);
484 
485 PETSC_EXTERN PetscErrorCode SNESUpdateCheckJacobian(SNES,PetscInt);
486 
487 PETSC_EXTERN PetscErrorCode SNESShellGetContext(SNES,void**);
488 PETSC_EXTERN PetscErrorCode SNESShellSetContext(SNES,void*);
489 PETSC_EXTERN PetscErrorCode SNESShellSetSolve(SNES,PetscErrorCode (*)(SNES,Vec));
490 
491 /* --------- Routines specifically for line search methods --------------- */
492 
493 typedef struct _p_LineSearch* SNESLineSearch;
494 
495 /*S
496      SNESLineSearch - Abstract PETSc object that manages line-search operations
497 
498    Level: beginner
499 
500   Concepts: nonlinear solvers, line search
501 
502 .seealso:  SNESLineSearchCreate(), SNESLineSearchSetType(), SNES
503 S*/
504 
505 /*J
506     SNESLineSearchType - String with the name of a PETSc line search method
507 
508    Level: beginner
509 
510 .seealso: SNESLineSearchSetType(), SNES
511 J*/
512 
513 typedef const char* SNESLineSearchType;
514 #define SNESLINESEARCHBT                 "bt"
515 #define SNESLINESEARCHBASIC              "basic"
516 #define SNESLINESEARCHL2                 "l2"
517 #define SNESLINESEARCHCP                 "cp"
518 #define SNESLINESEARCHSHELL              "shell"
519 
520 PETSC_EXTERN PetscBool         SNESRegisterAllCalled;
521 PETSC_EXTERN PetscFunctionList SNESList;
522 PETSC_EXTERN PetscClassId      SNESLINESEARCH_CLASSID;
523 PETSC_EXTERN PetscBool         SNESLineSearchRegisterAllCalled;
524 PETSC_EXTERN PetscFunctionList SNESLineSearchList;
525 PETSC_EXTERN PetscLogEvent     SNESLineSearch_Apply;
526 
527 #define SNES_LINESEARCH_ORDER_LINEAR    1
528 #define SNES_LINESEARCH_ORDER_QUADRATIC 2
529 #define SNES_LINESEARCH_ORDER_CUBIC     3
530 
531 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVIProjectFunc)(SNES,Vec);
532 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchVINormFunc)(SNES,Vec,Vec,PetscReal *);
533 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchApplyFunc)(SNESLineSearch);
534 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*SNESLineSearchUserFunc)(SNESLineSearch, void *);
535 
536 PETSC_EXTERN PetscErrorCode SNESLineSearchCreate(MPI_Comm, SNESLineSearch*);
537 PETSC_EXTERN PetscErrorCode SNESLineSearchReset(SNESLineSearch);
538 PETSC_EXTERN PetscErrorCode SNESLineSearchView(SNESLineSearch,PetscViewer);
539 PETSC_EXTERN PetscErrorCode SNESLineSearchDestroy(SNESLineSearch *);
540 PETSC_EXTERN PetscErrorCode SNESLineSearchSetType(SNESLineSearch, SNESLineSearchType);
541 PETSC_EXTERN PetscErrorCode SNESLineSearchSetFromOptions(SNESLineSearch);
542 PETSC_EXTERN PetscErrorCode SNESLineSearchSetUp(SNESLineSearch);
543 PETSC_EXTERN PetscErrorCode SNESLineSearchApply(SNESLineSearch, Vec, Vec, PetscReal *, Vec);
544 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheck(SNESLineSearch,Vec,Vec,PetscBool *);
545 PETSC_EXTERN PetscErrorCode SNESLineSearchPostCheck(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *);
546 PETSC_EXTERN PetscErrorCode SNESLineSearchGetWork(SNESLineSearch, PetscInt);
547 
548 /* set the functions for precheck and postcheck */
549 
550 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPreCheck(SNESLineSearch, PetscErrorCode (*SNESLineSearchPreCheckFunction)(SNESLineSearch,Vec,Vec,PetscBool*,void*), void *ctx);
551 PETSC_EXTERN PetscErrorCode SNESLineSearchSetPostCheck(SNESLineSearch, PetscErrorCode (*SNESLineSearchPostCheckFunction)(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *,void*), void *ctx);
552 
553 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPreCheck(SNESLineSearch, PetscErrorCode (**SNESLineSearchPreCheckFunction)(SNESLineSearch,Vec,Vec,PetscBool*,void*), void **ctx);
554 PETSC_EXTERN PetscErrorCode SNESLineSearchGetPostCheck(SNESLineSearch, PetscErrorCode (**SNESLineSearchPostCheckFunction)(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *,void*), void **ctx);
555 
556 /* set the functions for VI-specific line search operations */
557 
558 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc, SNESLineSearchVINormFunc);
559 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc*, SNESLineSearchVINormFunc*);
560 
561 /* pointers to the associated SNES in order to be able to get the function evaluation out */
562 PETSC_EXTERN PetscErrorCode SNESLineSearchSetSNES(SNESLineSearch,SNES);
563 PETSC_EXTERN PetscErrorCode SNESLineSearchGetSNES(SNESLineSearch,SNES*);
564 
565 /* set and get the parameters and vectors */
566 PETSC_EXTERN PetscErrorCode SNESLineSearchGetTolerances(SNESLineSearch,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscInt*);
567 PETSC_EXTERN PetscErrorCode SNESLineSearchSetTolerances(SNESLineSearch,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscInt);
568 
569 PETSC_EXTERN PetscErrorCode SNESLineSearchPreCheckPicard(SNESLineSearch,Vec,Vec,PetscBool*,void*);
570 
571 PETSC_EXTERN PetscErrorCode SNESLineSearchGetLambda(SNESLineSearch,PetscReal*);
572 PETSC_EXTERN PetscErrorCode SNESLineSearchSetLambda(SNESLineSearch,PetscReal);
573 
574 PETSC_EXTERN PetscErrorCode SNESLineSearchGetDamping(SNESLineSearch,PetscReal*);
575 PETSC_EXTERN PetscErrorCode SNESLineSearchSetDamping(SNESLineSearch,PetscReal);
576 
577 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOrder(SNESLineSearch,PetscInt *order);
578 PETSC_EXTERN PetscErrorCode SNESLineSearchSetOrder(SNESLineSearch,PetscInt order);
579 
580 PETSC_EXTERN PetscErrorCode SNESLineSearchGetSuccess(SNESLineSearch, PetscBool*);
581 PETSC_EXTERN PetscErrorCode SNESLineSearchSetSuccess(SNESLineSearch, PetscBool);
582 
583 PETSC_EXTERN PetscErrorCode SNESLineSearchGetVecs(SNESLineSearch,Vec*,Vec*,Vec*,Vec*,Vec*);
584 PETSC_EXTERN PetscErrorCode SNESLineSearchSetVecs(SNESLineSearch,Vec,Vec,Vec,Vec,Vec);
585 
586 PETSC_EXTERN PetscErrorCode SNESLineSearchGetNorms(SNESLineSearch, PetscReal *, PetscReal *, PetscReal *);
587 PETSC_EXTERN PetscErrorCode SNESLineSearchSetNorms(SNESLineSearch, PetscReal, PetscReal, PetscReal);
588 PETSC_EXTERN PetscErrorCode SNESLineSearchComputeNorms(SNESLineSearch);
589 PETSC_EXTERN PetscErrorCode SNESLineSearchSetComputeNorms(SNESLineSearch, PetscBool);
590 
591 PETSC_EXTERN PetscErrorCode SNESLineSearchSetMonitor(SNESLineSearch, PetscBool);
592 PETSC_EXTERN PetscErrorCode SNESLineSearchGetMonitor(SNESLineSearch, PetscViewer*);
593 
594 PETSC_EXTERN PetscErrorCode SNESLineSearchAppendOptionsPrefix(SNESLineSearch, const char prefix[]);
595 PETSC_EXTERN PetscErrorCode SNESLineSearchGetOptionsPrefix(SNESLineSearch, const char *prefix[]);
596 
597 
598 /* Shell interface functions */
599 PETSC_EXTERN PetscErrorCode SNESLineSearchShellSetUserFunc(SNESLineSearch,SNESLineSearchUserFunc,void*);
600 PETSC_EXTERN PetscErrorCode SNESLineSearchShellGetUserFunc(SNESLineSearch,SNESLineSearchUserFunc*,void**);
601 
602 /* BT interface functions */
603 PETSC_EXTERN PetscErrorCode SNESLineSearchBTSetAlpha(SNESLineSearch, PetscReal);
604 PETSC_EXTERN PetscErrorCode SNESLineSearchBTGetAlpha(SNESLineSearch, PetscReal*);
605 
606 /*register line search types */
607 PETSC_EXTERN PetscErrorCode SNESLineSearchRegister(const char[],const char[],const char[],PetscErrorCode(*)(SNESLineSearch));
608 PETSC_EXTERN PetscErrorCode SNESLineSearchRegisterAll(const char path[]);
609 PETSC_EXTERN PetscErrorCode SNESLineSearchRegisterDestroy(void);
610 
611 #if defined(PETSC_USE_DYNAMIC_LIBRARIES)
612 #define SNESLineSearchRegisterDynamic(a,b,c,d) SNESLineSearchRegister(a,b,c,0)
613 #else
614 #define SNESLineSearchRegisterDynamic(a,b,c,d) SNESLineSearchRegister(a,b,c,d)
615 #endif
616 
617 /* Routines for VI solver */
618 PETSC_EXTERN PetscErrorCode SNESVISetVariableBounds(SNES,Vec,Vec);
619 PETSC_EXTERN PetscErrorCode SNESVISetComputeVariableBounds(SNES, PetscErrorCode (*)(SNES,Vec,Vec));
620 PETSC_EXTERN PetscErrorCode SNESVIGetInactiveSet(SNES,IS*);
621 PETSC_EXTERN PetscErrorCode SNESVIGetActiveSetIS(SNES,Vec,Vec,IS*);
622 PETSC_EXTERN PetscErrorCode SNESVIComputeInactiveSetFnorm(SNES,Vec,Vec,PetscReal*);
623 PETSC_EXTERN PetscErrorCode SNESVISetRedundancyCheck(SNES,PetscErrorCode(*)(SNES,IS,IS*,void*),void*);
624 #define SNES_VI_INF   1.0e20
625 #define SNES_VI_NINF -1.0e20
626 
627 PETSC_EXTERN PetscErrorCode SNESTestLocalMin(SNES);
628 
629 /* Should this routine be private? */
630 PETSC_EXTERN PetscErrorCode SNESComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*);
631 
632 PETSC_EXTERN PetscErrorCode SNESSetDM(SNES,DM);
633 PETSC_EXTERN PetscErrorCode SNESGetDM(SNES,DM*);
634 PETSC_EXTERN PetscErrorCode SNESSetPC(SNES,SNES);
635 PETSC_EXTERN PetscErrorCode SNESGetPC(SNES,SNES*);
636 PETSC_EXTERN PetscErrorCode SNESSetPCSide(SNES,PCSide);
637 PETSC_EXTERN PetscErrorCode SNESGetPCSide(SNES,PCSide*);
638 PETSC_EXTERN PetscErrorCode SNESSetSNESLineSearch(SNES,SNESLineSearch);
639 PETSC_EXTERN PetscErrorCode SNESGetSNESLineSearch(SNES,SNESLineSearch*);
640 PETSC_EXTERN PetscErrorCode SNESRestrictHookAdd(SNES,PetscErrorCode (*)(SNES,SNES,void*),void*);
641 PETSC_EXTERN PetscErrorCode SNESRestrictHooksRun(SNES,SNES);
642 
643 PETSC_EXTERN PetscErrorCode SNESSetUpMatrices(SNES);
644 PETSC_EXTERN PetscErrorCode DMSNESSetFunction(DM,PetscErrorCode(*SNESFunction)(SNES,Vec,Vec,void*),void*);
645 PETSC_EXTERN PetscErrorCode DMSNESGetFunction(DM,PetscErrorCode(**SNESSetFunction)(SNES,Vec,Vec,void*),void**);
646 PETSC_EXTERN PetscErrorCode DMSNESSetGS(DM,PetscErrorCode(*SNESGSFunction)(SNES,Vec,Vec,void*),void*);
647 PETSC_EXTERN PetscErrorCode DMSNESGetGS(DM,PetscErrorCode(**SNESGSFunction)(SNES,Vec,Vec,void*),void**);
648 PETSC_EXTERN PetscErrorCode DMSNESSetJacobian(DM,PetscErrorCode(*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
649 PETSC_EXTERN PetscErrorCode DMSNESGetJacobian(DM,PetscErrorCode(**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
650 PETSC_EXTERN PetscErrorCode DMSNESSetPicard(DM,PetscErrorCode(*SNESFunction)(SNES,Vec,Vec,void*),PetscErrorCode(*SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
651 PETSC_EXTERN PetscErrorCode DMSNESGetPicard(DM,PetscErrorCode(**SNESFunction)(SNES,Vec,Vec,void*),PetscErrorCode(**SNESJacobianFunction)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
652 PETSC_EXTERN PetscErrorCode DMSNESSetObjective(DM,PetscErrorCode (*SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void*);
653 PETSC_EXTERN PetscErrorCode DMSNESGetObjective(DM,PetscErrorCode (**SNESObjectiveFunction)(SNES,Vec,PetscReal *,void*),void**);
654 
655 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESFunction)(DMDALocalInfo*,void*,void*,void*);
656 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESJacobian)(DMDALocalInfo*,void*,Mat,Mat,MatStructure*,void*);
657 PETSC_EXTERN_TYPEDEF typedef PetscErrorCode (*DMDASNESObjective)(DMDALocalInfo*,void*,PetscReal*,void*);
658 
659 PETSC_EXTERN PetscErrorCode DMDASNESSetFunctionLocal(DM,InsertMode,DMDASNESFunction,void*);
660 PETSC_EXTERN PetscErrorCode DMDASNESSetJacobianLocal(DM,DMDASNESJacobian,void*);
661 PETSC_EXTERN PetscErrorCode DMDASNESSetObjectiveLocal(DM,DMDASNESObjective,void*);
662 PETSC_EXTERN PetscErrorCode DMDASNESSetPicardLocal(DM,InsertMode,PetscErrorCode (*)(DMDALocalInfo*,void*,void*,void*),PetscErrorCode (*)(DMDALocalInfo*,void*,Mat,Mat,MatStructure*,void*),void*);
663 
664 PETSC_EXTERN PetscErrorCode DMSNESSetFunctionLocal(DM,PetscErrorCode (*)(DM,Vec,Vec,void*),void*);
665 PETSC_EXTERN PetscErrorCode DMSNESSetJacobianLocal(DM,PetscErrorCode (*)(DM,Vec,Mat,Mat,MatStructure*,void*),void*);
666 
667 /* Routines for Multiblock solver */
668 PETSC_EXTERN PetscErrorCode SNESMultiblockSetFields(SNES, const char [], PetscInt, const PetscInt *);
669 PETSC_EXTERN PetscErrorCode SNESMultiblockSetIS(SNES, const char [], IS);
670 PETSC_EXTERN PetscErrorCode SNESMultiblockSetBlockSize(SNES, PetscInt);
671 PETSC_EXTERN PetscErrorCode SNESMultiblockSetType(SNES, PCCompositeType);
672 
673 /*J
674     SNESMSType - String with the name of a PETSc SNESMS method.
675 
676    Level: intermediate
677 
678 .seealso: SNESMSSetType(), SNES
679 J*/
680 typedef const char* SNESMSType;
681 #define SNESMSM62       "m62"
682 #define SNESMSEULER     "euler"
683 #define SNESMSJAMESON83 "jameson83"
684 #define SNESMSVLTP21    "vltp21"
685 #define SNESMSVLTP31    "vltp31"
686 #define SNESMSVLTP41    "vltp41"
687 #define SNESMSVLTP51    "vltp51"
688 #define SNESMSVLTP61    "vltp61"
689 
690 PETSC_EXTERN PetscErrorCode SNESMSRegister(SNESMSType,PetscInt,PetscInt,PetscReal,const PetscReal[],const PetscReal[],const PetscReal[]);
691 PETSC_EXTERN PetscErrorCode SNESMSSetType(SNES,SNESMSType);
692 PETSC_EXTERN PetscErrorCode SNESMSFinalizePackage(void);
693 PETSC_EXTERN PetscErrorCode SNESMSInitializePackage(const char path[]);
694 PETSC_EXTERN PetscErrorCode SNESMSRegisterDestroy(void);
695 PETSC_EXTERN PetscErrorCode SNESMSRegisterAll(void);
696 
697 /* routines for NGMRES solver */
698 
699 typedef enum {
700   SNES_NGMRES_RESTART_NONE       = 0,
701   SNES_NGMRES_RESTART_PERIODIC   = 1,
702   SNES_NGMRES_RESTART_DIFFERENCE = 2} SNESNGMRESRestartType;
703 PETSC_EXTERN const char *const SNESNGMRESRestartTypes[];
704 
705 typedef enum {
706   SNES_NGMRES_SELECT_NONE       = 0,
707   SNES_NGMRES_SELECT_DIFFERENCE = 1,
708   SNES_NGMRES_SELECT_LINESEARCH = 2} SNESNGMRESSelectType;
709 PETSC_EXTERN const char *const SNESNGMRESSelectTypes[];
710 
711 PETSC_EXTERN PetscErrorCode SNESNGMRESSetRestartType(SNES, SNESNGMRESRestartType);
712 PETSC_EXTERN PetscErrorCode SNESNGMRESSetSelectType(SNES, SNESNGMRESSelectType);
713 
714 /* routines for NCG solver */
715 
716 typedef enum {
717   SNES_NCG_FR    = 0,
718   SNES_NCG_PRP   = 1,
719   SNES_NCG_HS    = 2,
720   SNES_NCG_DY    = 3,
721   SNES_NCG_CD    = 4} SNESNCGType;
722 PETSC_EXTERN const char *const SNESNCGTypes[];
723 
724 PETSC_EXTERN PetscErrorCode SNESNCGSetType(SNES, SNESNCGType);
725 
726 typedef enum {SNES_QN_SCALE_NONE       = 0,
727               SNES_QN_SCALE_SHANNO     = 1,
728               SNES_QN_SCALE_LINESEARCH = 2,
729               SNES_QN_SCALE_JACOBIAN   = 3} SNESQNScaleType;
730 PETSC_EXTERN const char *const SNESQNScaleTypes[];
731 typedef enum {SNES_QN_RESTART_NONE     = 0,
732               SNES_QN_RESTART_POWELL   = 1,
733               SNES_QN_RESTART_PERIODIC = 2} SNESQNRestartType;
734 PETSC_EXTERN const char *const SNESQNRestartTypes[];
735 
736 PETSC_EXTERN PetscErrorCode SNESQNSetScaleType(SNES, SNESQNScaleType);
737 PETSC_EXTERN PetscErrorCode SNESQNSetRestartType(SNES, SNESQNRestartType);
738 
739 
740 #endif
741