xref: /petsc/include/petscsnes.h (revision 8e557f584f98cd8a7c1317c0aa5ff7ad842b82ba)
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 PETSC_EXTERN_CXX_BEGIN
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 #define SNESType char*
31 #define SNESLS           "ls"
32 #define SNESTR           "tr"
33 #define SNESPYTHON       "python"
34 #define SNESTEST         "test"
35 #define SNESNRICHARDSON  "nrichardson"
36 #define SNESKSPONLY      "ksponly"
37 #define SNESVIRS         "virs"
38 #define SNESVISS         "viss"
39 #define SNESNGMRES       "ngmres"
40 #define SNESQN           "qn"
41 #define SNESSHELL        "shell"
42 #define SNESGS           "gs"
43 #define SNESNCG          "ncg"
44 #define SNESSORQN        "sorqn"
45 #define SNESFAS          "fas"
46 #define SNESMS           "ms"
47 
48 /* Logging support */
49 extern PetscClassId  SNES_CLASSID;
50 
51 extern PetscErrorCode  SNESInitializePackage(const char[]);
52 
53 extern PetscErrorCode  SNESCreate(MPI_Comm,SNES*);
54 extern PetscErrorCode  SNESReset(SNES);
55 extern PetscErrorCode  SNESDestroy(SNES*);
56 extern PetscErrorCode  SNESSetType(SNES,const SNESType);
57 extern PetscErrorCode  SNESMonitor(SNES,PetscInt,PetscReal);
58 extern PetscErrorCode  SNESMonitorSet(SNES,PetscErrorCode(*)(SNES,PetscInt,PetscReal,void*),void *,PetscErrorCode (*)(void**));
59 extern PetscErrorCode  SNESMonitorCancel(SNES);
60 extern PetscErrorCode  SNESSetConvergenceHistory(SNES,PetscReal[],PetscInt[],PetscInt,PetscBool );
61 extern PetscErrorCode  SNESGetConvergenceHistory(SNES,PetscReal*[],PetscInt *[],PetscInt *);
62 extern PetscErrorCode  SNESSetUp(SNES);
63 extern PetscErrorCode  SNESSolve(SNES,Vec,Vec);
64 extern PetscErrorCode  SNESSetErrorIfNotConverged(SNES,PetscBool );
65 extern PetscErrorCode  SNESGetErrorIfNotConverged(SNES,PetscBool  *);
66 
67 
68 extern PetscErrorCode  SNESAddOptionsChecker(PetscErrorCode (*)(SNES));
69 
70 extern PetscErrorCode  SNESSetUpdate(SNES, PetscErrorCode (*)(SNES, PetscInt));
71 extern PetscErrorCode  SNESDefaultUpdate(SNES, PetscInt);
72 
73 extern PetscFList SNESList;
74 extern PetscErrorCode  SNESRegisterDestroy(void);
75 extern PetscErrorCode  SNESRegisterAll(const char[]);
76 
77 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    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 extern PetscErrorCode  SNESGetKSP(SNES,KSP*);
129 extern PetscErrorCode  SNESSetKSP(SNES,KSP);
130 extern PetscErrorCode  SNESGetSolution(SNES,Vec*);
131 extern PetscErrorCode  SNESGetSolutionUpdate(SNES,Vec*);
132 extern PetscErrorCode  SNESGetRhs(SNES,Vec*);
133 extern PetscErrorCode  SNESView(SNES,PetscViewer);
134 
135 extern PetscErrorCode  SNESSetOptionsPrefix(SNES,const char[]);
136 extern PetscErrorCode  SNESAppendOptionsPrefix(SNES,const char[]);
137 extern PetscErrorCode  SNESGetOptionsPrefix(SNES,const char*[]);
138 extern PetscErrorCode  SNESSetFromOptions(SNES);
139 extern PetscErrorCode  SNESDefaultGetWork(SNES,PetscInt);
140 
141 extern PetscErrorCode  MatCreateSNESMF(SNES,Mat*);
142 extern PetscErrorCode  MatMFFDComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
143 
144 extern PetscErrorCode  MatDAADSetSNES(Mat,SNES);
145 
146 extern PetscErrorCode  SNESGetType(SNES,const SNESType*);
147 extern PetscErrorCode  SNESMonitorDefault(SNES,PetscInt,PetscReal,void *);
148 extern PetscErrorCode  SNESMonitorRange(SNES,PetscInt,PetscReal,void *);
149 extern PetscErrorCode  SNESMonitorRatio(SNES,PetscInt,PetscReal,void *);
150 extern PetscErrorCode  SNESMonitorSetRatio(SNES,PetscViewer);
151 extern PetscErrorCode  SNESMonitorSolution(SNES,PetscInt,PetscReal,void *);
152 extern PetscErrorCode  SNESMonitorResidual(SNES,PetscInt,PetscReal,void *);
153 extern PetscErrorCode  SNESMonitorSolutionUpdate(SNES,PetscInt,PetscReal,void *);
154 extern PetscErrorCode  SNESMonitorDefaultShort(SNES,PetscInt,PetscReal,void *);
155 extern PetscErrorCode  SNESSetTolerances(SNES,PetscReal,PetscReal,PetscReal,PetscInt,PetscInt);
156 extern PetscErrorCode  SNESGetTolerances(SNES,PetscReal*,PetscReal*,PetscReal*,PetscInt*,PetscInt*);
157 extern PetscErrorCode  SNESSetTrustRegionTolerance(SNES,PetscReal);
158 extern PetscErrorCode  SNESGetFunctionNorm(SNES,PetscReal*);
159 extern PetscErrorCode  SNESSetFunctionNorm(SNES,PetscReal);
160 extern PetscErrorCode  SNESGetIterationNumber(SNES,PetscInt*);
161 extern PetscErrorCode  SNESSetIterationNumber(SNES,PetscInt);
162 
163 extern PetscErrorCode  SNESGetNonlinearStepFailures(SNES,PetscInt*);
164 extern PetscErrorCode  SNESSetMaxNonlinearStepFailures(SNES,PetscInt);
165 extern PetscErrorCode  SNESGetMaxNonlinearStepFailures(SNES,PetscInt*);
166 extern PetscErrorCode  SNESGetNumberFunctionEvals(SNES,PetscInt*);
167 
168 extern PetscErrorCode  SNESSetLagPreconditioner(SNES,PetscInt);
169 extern PetscErrorCode  SNESGetLagPreconditioner(SNES,PetscInt*);
170 extern PetscErrorCode  SNESSetLagJacobian(SNES,PetscInt);
171 extern PetscErrorCode  SNESGetLagJacobian(SNES,PetscInt*);
172 extern PetscErrorCode  SNESSetGridSequence(SNES,PetscInt);
173 
174 extern PetscErrorCode  SNESGetLinearSolveIterations(SNES,PetscInt*);
175 extern PetscErrorCode  SNESGetLinearSolveFailures(SNES,PetscInt*);
176 extern PetscErrorCode  SNESSetMaxLinearSolveFailures(SNES,PetscInt);
177 extern PetscErrorCode  SNESGetMaxLinearSolveFailures(SNES,PetscInt*);
178 
179 extern PetscErrorCode  SNESKSPSetUseEW(SNES,PetscBool );
180 extern PetscErrorCode  SNESKSPGetUseEW(SNES,PetscBool *);
181 extern PetscErrorCode  SNESKSPSetParametersEW(SNES,PetscInt,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal);
182 extern PetscErrorCode  SNESKSPGetParametersEW(SNES,PetscInt*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*);
183 
184 extern PetscErrorCode  SNESMonitorLGCreate(const char[],const char[],int,int,int,int,PetscDrawLG*);
185 extern PetscErrorCode  SNESMonitorLG(SNES,PetscInt,PetscReal,void*);
186 extern PetscErrorCode  SNESMonitorLGDestroy(PetscDrawLG*);
187 extern PetscErrorCode  SNESMonitorLGRangeCreate(const char[],const char[],int,int,int,int,PetscDrawLG*);
188 extern PetscErrorCode  SNESMonitorLGRange(SNES,PetscInt,PetscReal,void*);
189 extern PetscErrorCode  SNESMonitorLGRangeDestroy(PetscDrawLG*);
190 
191 extern PetscErrorCode  SNESSetApplicationContext(SNES,void *);
192 extern PetscErrorCode  SNESGetApplicationContext(SNES,void *);
193 extern PetscErrorCode  SNESSetComputeApplicationContext(SNES,PetscErrorCode (*)(SNES,void**),PetscErrorCode (*)(void**));
194 
195 extern PetscErrorCode  SNESPythonSetType(SNES,const char[]);
196 
197 extern PetscErrorCode  SNESSetFunctionDomainError(SNES);
198 extern PetscErrorCode  SNESGetFunctionDomainError(SNES, PetscBool *);
199 
200 /*E
201     SNESConvergedReason - reason a SNES method was said to
202          have converged or diverged
203 
204    Level: beginner
205 
206    The two most common reasons for divergence are
207 $   1) an incorrectly coded or computed Jacobian or
208 $   2) failure or lack of convergence in the linear system (in this case we recommend
209 $      testing with -pc_type lu to eliminate the linear solver as the cause of the problem).
210 
211    Diverged Reasons:
212 .    SNES_DIVERGED_LOCAL_MIN - this can only occur when using the line-search variant of SNES.
213        The line search wants to minimize Q(alpha) = 1/2 || F(x + alpha s) ||^2_2  this occurs
214        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
215        you get Q'(alpha) = -F(x)^T F'(x)^(-1)^T F'(x+alpha s)F(x+alpha s); when alpha = 0
216        Q'(0) = - ||F(x)||^2_2 which is always NEGATIVE if F'(x) is invertible. This means the Newton
217        direction is a descent direction and the line search should succeed if alpha is small enough.
218 
219        If F'(x) is NOT invertible AND F'(x)^T F(x) = 0 then Q'(0) = 0 and the Newton direction
220        is NOT a descent direction so the line search will fail. All one can do at this point
221        is change the initial guess and try again.
222 
223        An alternative explanation: Newton's method can be regarded as replacing the function with
224        its linear approximation and minimizing the 2-norm of that. That is F(x+s) approx F(x) + F'(x)s
225        so we minimize || F(x) + F'(x) s ||^2_2; do this using Least Squares. If F'(x) is invertible then
226        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
227        exists a nontrival (that is F'(x)s != 0) solution to the equation and this direction is
228        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)
229        = - (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
230        and F'(x)^T F'(x) has no negative eigenvalues Q'(0) < 0 so s is a descent direction and the line
231        search should succeed for small enough alpha.
232 
233        Note that this RARELY happens in practice. Far more likely the linear system is not being solved
234        (well enough?) or the Jacobian is wrong.
235 
236    SNES_DIVERGED_MAX_IT means that the solver reached the maximum number of iterations without satisfying any
237    convergence criteria. SNES_CONVERGED_ITS means that SNESSkipConverged() was chosen as the convergence test;
238    thus the usual convergence criteria have not been checked and may or may not be satisfied.
239 
240    Developer Notes: this must match finclude/petscsnes.h
241 
242        The string versions of these are in SNESConvergedReason, if you change any value here you must
243      also adjust that array.
244 
245    Each reason has its own manual page.
246 
247 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPConvergedReason, SNESSetConvergenceTest()
248 E*/
249 typedef enum {/* converged */
250               SNES_CONVERGED_FNORM_ABS         =  2, /* ||F|| < atol */
251               SNES_CONVERGED_FNORM_RELATIVE    =  3, /* ||F|| < rtol*||F_initial|| */
252               SNES_CONVERGED_SNORM_RELATIVE    =  4, /* Newton computed step size small; || delta x || < stol */
253               SNES_CONVERGED_ITS               =  5, /* maximum iterations reached */
254               SNES_CONVERGED_TR_DELTA          =  7,
255               /* diverged */
256               SNES_DIVERGED_FUNCTION_DOMAIN     = -1, /* the new x location passed the function is not in the domain of F */
257               SNES_DIVERGED_FUNCTION_COUNT      = -2,
258               SNES_DIVERGED_LINEAR_SOLVE        = -3, /* the linear solve failed */
259               SNES_DIVERGED_FNORM_NAN           = -4,
260               SNES_DIVERGED_MAX_IT              = -5,
261               SNES_DIVERGED_LINE_SEARCH         = -6, /* the line search failed */
262               SNES_DIVERGED_INNER               = -7, /* inner solve failed */
263               SNES_DIVERGED_LOCAL_MIN           = -8, /* || J^T b || is small, implies converged to local minimum of F() */
264               SNES_CONVERGED_ITERATING          =  0} SNESConvergedReason;
265 extern const char *const*SNESConvergedReasons;
266 
267 /*MC
268      SNES_CONVERGED_FNORM_ABS - 2-norm(F) <= abstol
269 
270    Level: beginner
271 
272 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
273 
274 M*/
275 
276 /*MC
277      SNES_CONVERGED_FNORM_RELATIVE - 2-norm(F) <= rtol*2-norm(F(x_0)) where x_0 is the initial guess
278 
279    Level: beginner
280 
281 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
282 
283 M*/
284 
285 /*MC
286      SNES_CONVERGED_SNORM_RELATIVE - The 2-norm of the last step <= stol * 2-norm(x) where x is the current
287           solution and stol is the 4th argument to SNESSetTolerances()
288 
289      Options Database Keys:
290       -snes_stol <stol> - the step tolerance
291 
292    Level: beginner
293 
294 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
295 
296 M*/
297 
298 /*MC
299      SNES_DIVERGED_FUNCTION_COUNT - The user provided function has been called more times then the final
300          argument to SNESSetTolerances()
301 
302    Level: beginner
303 
304 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
305 
306 M*/
307 
308 /*MC
309      SNES_DIVERGED_FNORM_NAN - the 2-norm of the current function evaluation is not-a-number (NaN), this
310       is usually caused by a division of 0 by 0.
311 
312    Level: beginner
313 
314 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
315 
316 M*/
317 
318 /*MC
319      SNES_DIVERGED_MAX_IT - SNESSolve() has reached the maximum number of iterations requested
320 
321    Level: beginner
322 
323 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
324 
325 M*/
326 
327 /*MC
328      SNES_DIVERGED_LINE_SEARCH - The line search has failed. This only occurs for a SNESType of SNESLS
329 
330    Level: beginner
331 
332 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
333 
334 M*/
335 
336 /*MC
337      SNES_DIVERGED_LOCAL_MIN - the algorithm seems to have stagnated at a local minimum that is not zero.
338         See the manual page for SNESConvergedReason for more details
339 
340    Level: beginner
341 
342 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
343 
344 M*/
345 
346 /*MC
347      SNES_CONERGED_ITERATING - this only occurs if SNESGetConvergedReason() is called during the SNESSolve()
348 
349    Level: beginner
350 
351 .seealso:  SNESSolve(), SNESGetConvergedReason(), SNESConvergedReason, SNESSetTolerances()
352 
353 M*/
354 
355 extern PetscErrorCode  SNESSetConvergenceTest(SNES,PetscErrorCode (*)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*),void*,PetscErrorCode (*)(void*));
356 extern PetscErrorCode  SNESDefaultConverged(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
357 extern PetscErrorCode  SNESSkipConverged(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
358 extern PetscErrorCode  SNESGetConvergedReason(SNES,SNESConvergedReason*);
359 
360 extern PetscErrorCode  SNESDMDAComputeFunction(SNES,Vec,Vec,void*);
361 extern PetscErrorCode  SNESDMDAComputeJacobianWithAdic(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
362 extern PetscErrorCode  SNESDMDAComputeJacobianWithAdifor(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
363 extern PetscErrorCode  SNESDMDAComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
364 
365 extern PetscErrorCode SNESDMMeshComputeFunction(SNES,Vec,Vec,void*);
366 extern PetscErrorCode SNESDMMeshComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
367 extern PetscErrorCode SNESDMComplexComputeFunction(SNES,Vec,Vec,void *);
368 extern PetscErrorCode SNESDMComplexComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
369 
370 /* --------- Solving systems of nonlinear equations --------------- */
371 typedef PetscErrorCode (*SNESFunction)(SNES,Vec,Vec,void*);
372 typedef PetscErrorCode (*SNESJacobian)(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
373 typedef PetscErrorCode (*SNESGSFunction)(SNES,Vec,Vec,void*);
374 extern PetscErrorCode  SNESSetFunction(SNES,Vec,SNESFunction,void*);
375 extern PetscErrorCode  SNESGetFunction(SNES,Vec*,SNESFunction*,void**);
376 extern PetscErrorCode  SNESComputeFunction(SNES,Vec,Vec);
377 extern PetscErrorCode  SNESSetJacobian(SNES,Mat,Mat,SNESJacobian,void*);
378 extern PetscErrorCode  SNESGetJacobian(SNES,Mat*,Mat*,SNESJacobian*,void**);
379 extern PetscErrorCode  SNESDefaultComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
380 extern PetscErrorCode  SNESDefaultComputeJacobianColor(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
381 extern PetscErrorCode  SNESSetComputeInitialGuess(SNES,PetscErrorCode (*)(SNES,Vec,void*),void*);
382 extern PetscErrorCode  SNESSetPicard(SNES,Vec,SNESFunction,Mat,Mat,SNESJacobian,void*);
383 extern PetscErrorCode  SNESGetPicard(SNES,Vec*,SNESFunction*,Mat*,SNESJacobian*,void**);
384 extern PetscErrorCode  SNESSetInitialFunction(SNES,Vec);
385 extern PetscErrorCode  SNESSetInitialFunctionNorm(SNES,PetscReal);
386 
387 /*E
388     SNESNormType - Norm that is passed in the Krylov convergence
389        test routines.
390 
391    Level: advanced
392 
393    Support for these is highly dependent on the solver.
394 
395    Notes:
396    This is primarily used to turn off extra norm and function computation
397    when the solvers are composed.
398 
399 .seealso: SNESSolve(), SNESGetConvergedReason(), KSPSetNormType(),
400           KSPSetConvergenceTest(), KSPSetPCSide()
401 E*/
402 
403 typedef enum {SNES_NORM_DEFAULT            = -1,
404               SNES_NORM_INITIAL_ONLY       = 1,
405               SNES_NORM_FINAL_ONLY         = 2,
406               SNES_NORM_INITIAL_FINAL_ONLY = 3,
407               SNES_NORM_NONE               = 0} SNESNormType;
408 
409 
410 /*MC
411     SNES_NORM_DEFAULT - Compute the function and its L2 norm at each iteration.
412 
413    Level: advanced
414 
415     Notes:
416     Most solvers will use this no matter what norm type is passed to them.
417 
418 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_NONE
419 M*/
420 
421 /*MC
422     SNES_NORM_DEFAULT - Don't compute function and its L2 norm.
423 
424    Level: advanced
425 
426     Notes:
427     This is most useful for stationary solvers with a fixed number of iterations used as smoothers.
428 
429 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_DEFAULT
430 M*/
431 
432 
433 
434 /*MC
435     SNES_NORM_INITIAL_ONLY - Compute the function and its L2 at iteration 0, but do not update it.
436 
437    Level: advanced
438 
439    Notes:
440    This method is useful in composed methods, when a true solution might actually be found before SNESSolve() is called.
441    This option enables the solve to abort on the zeroth iteration if this is the case.
442 
443    For solvers that require the computation of the L2 norm of the function as part of the method, this merely cancels
444    the norm computation at the last iteration (if possible).
445 
446 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_FINAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
447 M*/
448 
449 /*MC
450     SNES_NORM_FINAL_ONLY - Compute the function and its L2 norm on only the final iteration.
451 
452    Level: advanced
453 
454    Notes:
455    For solvers that require the computation of the L2 norm of the function as part of the method, behaves
456    exactly as SNES_NORM_DEFAULT.  This method is useful when the function is gotten after SNESSolve and
457    used in subsequent computation for methods that do not need the norm computed during the rest of the
458    solution procedure.
459 
460 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_INITIAL_ONLY, SNES_NORM_INITIAL_FINAL_ONLY
461 M*/
462 
463 /*MC
464     SNES_NORM_INITIAL_FINAL_ONLY - Compute the function and its L2 norm on only the initial and final iterations.
465 
466    Level: advanced
467 
468    Notes:
469    This method combines the benefits of SNES_NORM_INITIAL_ONLY and SNES_NORM_FINAL_ONLY.
470 
471 .seealso: SNESNormType, SNESSetNormType(), SNES_NORM_SNES_NORM_INITIAL_ONLY, SNES_NORM_FINAL_ONLY
472 M*/
473 
474 
475 extern PetscErrorCode  SNESSetNormType(SNES,SNESNormType);
476 extern PetscErrorCode  SNESGetNormType(SNES,SNESNormType*);
477 
478 extern PetscErrorCode  SNESSetGS(SNES,SNESGSFunction,void*);
479 extern PetscErrorCode  SNESGetGS(SNES,SNESGSFunction*,void**);
480 extern PetscErrorCode  SNESSetUseGS(SNES,PetscBool);
481 extern PetscErrorCode  SNESGetUseGS(SNES,PetscBool *);
482 extern PetscErrorCode  SNESSetGSSweeps(SNES,PetscInt);
483 extern PetscErrorCode  SNESGetGSSweeps(SNES,PetscInt *);
484 extern PetscErrorCode  SNESComputeGS(SNES,Vec,Vec);
485 
486 extern PetscErrorCode  SNESShellGetContext(SNES,void**);
487 extern PetscErrorCode  SNESShellSetContext(SNES,void*);
488 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 #define SNESLineSearchType char*
513 #define SNESLINESEARCHBT                 "bt"
514 #define SNESLINESEARCHBASIC              "basic"
515 #define SNESLINESEARCHL2                 "l2"
516 #define SNESLINESEARCHCP                 "cp"
517 #define SNESLINESEARCHSHELL              "shell"
518 
519 extern PetscClassId  SNESLINESEARCH_CLASSID;
520 extern PetscBool     SNESLineSearchRegisterAllCalled;
521 extern PetscFList    SNESLineSearchList;
522 extern PetscLogEvent SNESLineSearch_Apply;
523 
524 typedef enum {SNES_LINESEARCH_LINEAR,
525               SNES_LINESEARCH_CUBIC,
526               SNES_LINESEARCH_QUADRATIC} SNESLineSearchOrder;
527 
528 typedef PetscErrorCode (*SNESLineSearchPreCheckFunc)(SNESLineSearch,Vec,Vec,PetscBool*,void*);
529 typedef PetscErrorCode (*SNESLineSearchVIProjectFunc)(SNES,Vec);
530 typedef PetscErrorCode (*SNESLineSearchVINormFunc)(SNES,Vec,Vec,PetscReal *);
531 typedef PetscErrorCode (*SNESLineSearchPostCheckFunc)(SNESLineSearch,Vec,Vec,Vec,PetscBool *,PetscBool *,void*);
532 typedef PetscErrorCode (*SNESLineSearchApplyFunc)(SNESLineSearch);
533 typedef PetscErrorCode (*SNESLineSearchUserFunc)(SNESLineSearch, void *);
534 
535 extern PetscErrorCode SNESLineSearchCreate(MPI_Comm, SNESLineSearch*);
536 extern PetscErrorCode SNESLineSearchReset(SNESLineSearch);
537 extern PetscErrorCode SNESLineSearchView(SNESLineSearch,PetscViewer);
538 extern PetscErrorCode SNESLineSearchDestroy(SNESLineSearch *);
539 extern PetscErrorCode SNESLineSearchSetType(SNESLineSearch, const SNESLineSearchType);
540 extern PetscErrorCode SNESLineSearchSetFromOptions(SNESLineSearch);
541 extern PetscErrorCode SNESLineSearchSetUp(SNESLineSearch);
542 extern PetscErrorCode SNESLineSearchApply(SNESLineSearch, Vec, Vec, PetscReal *, Vec);
543 extern PetscErrorCode SNESLineSearchPreCheck(SNESLineSearch, PetscBool *);
544 extern PetscErrorCode SNESLineSearchPostCheck(SNESLineSearch, PetscBool *, PetscBool *);
545 extern PetscErrorCode SNESLineSearchGetWork(SNESLineSearch, PetscInt);
546 
547 /* set the functions for precheck and postcheck */
548 
549 extern PetscErrorCode SNESLineSearchSetPreCheck(SNESLineSearch, SNESLineSearchPreCheckFunc, void *ctx);
550 extern PetscErrorCode SNESLineSearchSetPostCheck(SNESLineSearch, SNESLineSearchPostCheckFunc, void *ctx);
551 
552 extern PetscErrorCode SNESLineSearchGetPreCheck(SNESLineSearch, SNESLineSearchPreCheckFunc*, void **ctx);
553 extern PetscErrorCode SNESLineSearchGetPostCheck(SNESLineSearch, SNESLineSearchPostCheckFunc*, void **ctx);
554 
555 /* set the functions for VI-specific line search operations */
556 
557 extern PetscErrorCode SNESLineSearchSetVIFunctions(SNESLineSearch, SNESLineSearchVIProjectFunc, SNESLineSearchVINormFunc);
558 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 extern PetscErrorCode  SNESLineSearchSetSNES(SNESLineSearch,SNES);
562 extern PetscErrorCode  SNESLineSearchGetSNES(SNESLineSearch,SNES*);
563 
564 /* set and get the parameters and vectors */
565 extern PetscErrorCode  SNESLineSearchGetTolerances(SNESLineSearch,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscReal*,PetscInt*);
566 extern PetscErrorCode  SNESLineSearchSetTolerances(SNESLineSearch,PetscReal,PetscReal,PetscReal,PetscReal,PetscReal,PetscInt);
567 
568 extern PetscErrorCode SNESLineSearchPreCheckPicard(SNESLineSearch,Vec,Vec,PetscBool*,void*);
569 
570 extern PetscErrorCode  SNESLineSearchGetLambda(SNESLineSearch,PetscReal*);
571 extern PetscErrorCode  SNESLineSearchSetLambda(SNESLineSearch,PetscReal);
572 
573 extern PetscErrorCode  SNESLineSearchGetDamping(SNESLineSearch,PetscReal*);
574 extern PetscErrorCode  SNESLineSearchSetDamping(SNESLineSearch,PetscReal);
575 
576 extern PetscErrorCode  SNESLineSearchGetOrder(SNESLineSearch,SNESLineSearchOrder *order);
577 extern PetscErrorCode  SNESLineSearchSetOrder(SNESLineSearch,SNESLineSearchOrder order);
578 
579 extern PetscErrorCode  SNESLineSearchGetSuccess(SNESLineSearch, PetscBool*);
580 extern PetscErrorCode  SNESLineSearchSetSuccess(SNESLineSearch, PetscBool);
581 
582 extern PetscErrorCode SNESLineSearchGetVecs(SNESLineSearch,Vec*,Vec*,Vec*,Vec*,Vec*);
583 extern PetscErrorCode SNESLineSearchSetVecs(SNESLineSearch,Vec,Vec,Vec,Vec,Vec);
584 
585 extern PetscErrorCode SNESLineSearchGetNorms(SNESLineSearch, PetscReal *, PetscReal *, PetscReal *);
586 extern PetscErrorCode SNESLineSearchSetNorms(SNESLineSearch, PetscReal, PetscReal, PetscReal);
587 extern PetscErrorCode SNESLineSearchComputeNorms(SNESLineSearch);
588 extern PetscErrorCode SNESLineSearchSetComputeNorms(SNESLineSearch, PetscBool);
589 
590 extern PetscErrorCode  SNESLineSearchSetMonitor(SNESLineSearch, PetscBool);
591 extern PetscErrorCode  SNESLineSearchGetMonitor(SNESLineSearch, PetscViewer*);
592 
593 extern PetscErrorCode  SNESLineSearchAppendOptionsPrefix(SNESLineSearch, const char prefix[]);
594 extern PetscErrorCode  SNESLineSearchGetOptionsPrefix(SNESLineSearch, const char *prefix[]);
595 
596 
597 /* Shell interface functions */
598 extern PetscErrorCode SNESLineSearchShellSetUserFunc(SNESLineSearch,SNESLineSearchUserFunc,void*);
599 extern PetscErrorCode SNESLineSearchShellGetUserFunc(SNESLineSearch,SNESLineSearchUserFunc*,void**);
600 
601 /* BT interface functions */
602 extern PetscErrorCode SNESLineSearchBTSetAlpha(SNESLineSearch, PetscReal);
603 extern PetscErrorCode SNESLineSearchBTGetAlpha(SNESLineSearch, PetscReal*);
604 
605 /*register line search types */
606 extern PetscErrorCode SNESLineSearchRegister(const char[],const char[],const char[],PetscErrorCode(*)(SNESLineSearch));
607 extern PetscErrorCode SNESLineSearchRegisterAll(const char path[]);
608 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 extern PetscErrorCode  SNESVISetVariableBounds(SNES,Vec,Vec);
618 extern PetscErrorCode  SNESVISetComputeVariableBounds(SNES, PetscErrorCode (*)(SNES,Vec,Vec));
619 extern PetscErrorCode  SNESVIGetInactiveSet(SNES,IS*);
620 extern PetscErrorCode  SNESVIGetActiveSetIS(SNES,Vec,Vec,IS*);
621 extern PetscErrorCode  SNESVIComputeInactiveSetFnorm(SNES,Vec,Vec,PetscReal*);
622 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 extern PetscErrorCode  SNESTestLocalMin(SNES);
627 
628 /* Should this routine be private? */
629 extern PetscErrorCode  SNESComputeJacobian(SNES,Vec,Mat*,Mat*,MatStructure*);
630 
631 extern PetscErrorCode SNESSetDM(SNES,DM);
632 extern PetscErrorCode SNESGetDM(SNES,DM*);
633 extern PetscErrorCode SNESSetPC(SNES,SNES);
634 extern PetscErrorCode SNESGetPC(SNES,SNES*);
635 extern PetscErrorCode SNESSetSNESLineSearch(SNES,SNESLineSearch);
636 extern PetscErrorCode SNESGetSNESLineSearch(SNES,SNESLineSearch*);
637 extern PetscErrorCode SNESRestrictHookAdd(SNES,PetscErrorCode (*)(SNES,SNES,void*),void*);
638 extern PetscErrorCode SNESRestrictHooksRun(SNES,SNES);
639 
640 extern PetscErrorCode SNESSetUpMatrices(SNES);
641 extern PetscErrorCode DMSNESSetFunction(DM,PetscErrorCode(*)(SNES,Vec,Vec,void*),void*);
642 extern PetscErrorCode DMSNESGetFunction(DM,PetscErrorCode(**)(SNES,Vec,Vec,void*),void**);
643 extern PetscErrorCode DMSNESSetGS(DM,PetscErrorCode(*)(SNES,Vec,Vec,void*),void*);
644 extern PetscErrorCode DMSNESGetGS(DM,PetscErrorCode(**)(SNES,Vec,Vec,void*),void**);
645 extern PetscErrorCode DMSNESSetJacobian(DM,PetscErrorCode(*)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void*);
646 extern PetscErrorCode DMSNESGetJacobian(DM,PetscErrorCode(**)(SNES,Vec,Mat*,Mat*,MatStructure*,void*),void**);
647 
648 extern PetscErrorCode DMDASNESSetFunctionLocal(DM,PetscErrorCode(*)(DMDALocalInfo*,void*,void*,void*),void*);
649 extern PetscErrorCode DMDASNESSetJacobianLocal(DM,PetscErrorCode(*)(DMDALocalInfo*,void*,Mat,Mat,MatStructure*,void*),void*);
650 
651 /* Routines for Multiblock solver */
652 extern PetscErrorCode SNESMultiblockSetFields(SNES, const char [], PetscInt, const PetscInt *);
653 extern PetscErrorCode SNESMultiblockSetIS(SNES, const char [], IS);
654 extern PetscErrorCode SNESMultiblockSetBlockSize(SNES, PetscInt);
655 extern PetscErrorCode SNESMultiblockSetType(SNES, PCCompositeType);
656 
657 /*J
658     SNESMSType - String with the name of a PETSc SNESMS method.
659 
660    Level: intermediate
661 
662 .seealso: SNESMSSetType(), SNES
663 J*/
664 #define SNESMSType char*
665 #define SNESMSM62       "m62"
666 #define SNESMSEULER     "euler"
667 #define SNESMSJAMESON83 "jameson83"
668 #define SNESMSVLTP21    "vltp21"
669 #define SNESMSVLTP31    "vltp31"
670 #define SNESMSVLTP41    "vltp41"
671 #define SNESMSVLTP51    "vltp51"
672 #define SNESMSVLTP61    "vltp61"
673 
674 extern PetscErrorCode SNESMSRegister(const SNESMSType,PetscInt,PetscInt,PetscReal,const PetscReal[],const PetscReal[],const PetscReal[]);
675 extern PetscErrorCode SNESMSSetType(SNES,const SNESMSType);
676 extern PetscErrorCode SNESMSFinalizePackage(void);
677 extern PetscErrorCode SNESMSInitializePackage(const char path[]);
678 extern PetscErrorCode SNESMSRegisterDestroy(void);
679 extern PetscErrorCode SNESMSRegisterAll(void);
680 
681 PETSC_EXTERN_CXX_END
682 #endif
683