xref: /petsc/src/tao/interface/taosolver_fg.c (revision 4e8208cbcbc709572b8abe32f33c78b69c819375)
1 #include <petsc/private/taoimpl.h> /*I "petsctao.h" I*/
2 
3 /*@
4   TaoSetSolution - Sets the vector holding the initial guess for the solve
5 
6   Logically Collective
7 
8   Input Parameters:
9 + tao - the `Tao` context
10 - x0  - the initial guess
11 
12   Level: beginner
13 
14 .seealso: [](ch_tao), `Tao`, `TaoCreate()`, `TaoSolve()`, `TaoGetSolution()`
15 @*/
TaoSetSolution(Tao tao,Vec x0)16 PetscErrorCode TaoSetSolution(Tao tao, Vec x0)
17 {
18   PetscFunctionBegin;
19   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
20   if (x0) PetscValidHeaderSpecific(x0, VEC_CLASSID, 2);
21   PetscCall(PetscObjectReference((PetscObject)x0));
22   PetscCall(VecDestroy(&tao->solution));
23   tao->solution = x0;
24   PetscFunctionReturn(PETSC_SUCCESS);
25 }
26 
TaoTestGradient(Tao tao,Vec x,Vec g1)27 PetscErrorCode TaoTestGradient(Tao tao, Vec x, Vec g1)
28 {
29   Vec               g2, g3;
30   PetscBool         complete_print = PETSC_FALSE, test = PETSC_FALSE;
31   PetscReal         hcnorm, fdnorm, hcmax, fdmax, diffmax, diffnorm;
32   PetscScalar       dot;
33   MPI_Comm          comm;
34   PetscViewer       viewer, mviewer;
35   PetscViewerFormat format;
36   PetscInt          tabs;
37   static PetscBool  directionsprinted = PETSC_FALSE;
38 
39   PetscFunctionBegin;
40   PetscObjectOptionsBegin((PetscObject)tao);
41   PetscCall(PetscOptionsName("-tao_test_gradient", "Compare hand-coded and finite difference Gradients", "None", &test));
42   PetscCall(PetscOptionsViewer("-tao_test_gradient_view", "View difference between hand-coded and finite difference Gradients element entries", "None", &mviewer, &format, &complete_print));
43   PetscOptionsEnd();
44   if (!test) {
45     if (complete_print) PetscCall(PetscViewerDestroy(&mviewer));
46     PetscFunctionReturn(PETSC_SUCCESS);
47   }
48 
49   PetscCall(PetscObjectGetComm((PetscObject)tao, &comm));
50   PetscCall(PetscViewerASCIIGetStdout(comm, &viewer));
51   PetscCall(PetscViewerASCIIGetTab(viewer, &tabs));
52   PetscCall(PetscViewerASCIISetTab(viewer, ((PetscObject)tao)->tablevel));
53   PetscCall(PetscViewerASCIIPrintf(viewer, "  ---------- Testing Gradient -------------\n"));
54   if (!complete_print && !directionsprinted) {
55     PetscCall(PetscViewerASCIIPrintf(viewer, "  Run with -tao_test_gradient_view and optionally -tao_test_gradient <threshold> to show difference\n"));
56     PetscCall(PetscViewerASCIIPrintf(viewer, "    of hand-coded and finite difference gradient entries greater than <threshold>.\n"));
57   }
58   if (!directionsprinted) {
59     PetscCall(PetscViewerASCIIPrintf(viewer, "  Testing hand-coded Gradient, if (for double precision runs) ||G - Gfd||/||G|| is\n"));
60     PetscCall(PetscViewerASCIIPrintf(viewer, "    O(1.e-8), the hand-coded Gradient is probably correct.\n"));
61     directionsprinted = PETSC_TRUE;
62   }
63   if (complete_print) PetscCall(PetscViewerPushFormat(mviewer, format));
64 
65   PetscCall(VecDuplicate(x, &g2));
66   PetscCall(VecDuplicate(x, &g3));
67 
68   /* Compute finite difference gradient, assume the gradient is already computed by TaoComputeGradient() and put into g1 */
69   PetscCall(TaoDefaultComputeGradient(tao, x, g2, NULL));
70 
71   PetscCall(VecNorm(g2, NORM_2, &fdnorm));
72   PetscCall(VecNorm(g1, NORM_2, &hcnorm));
73   PetscCall(VecNorm(g2, NORM_INFINITY, &fdmax));
74   PetscCall(VecNorm(g1, NORM_INFINITY, &hcmax));
75   PetscCall(VecDot(g1, g2, &dot));
76   PetscCall(VecCopy(g1, g3));
77   PetscCall(VecAXPY(g3, -1.0, g2));
78   PetscCall(VecNorm(g3, NORM_2, &diffnorm));
79   PetscCall(VecNorm(g3, NORM_INFINITY, &diffmax));
80   PetscCall(PetscViewerASCIIPrintf(viewer, "  ||Gfd|| %g, ||G|| = %g, angle cosine = (Gfd'G)/||Gfd||||G|| = %g\n", (double)fdnorm, (double)hcnorm, (double)(PetscRealPart(dot) / (fdnorm * hcnorm))));
81   PetscCall(PetscViewerASCIIPrintf(viewer, "  2-norm ||G - Gfd||/||G|| = %g, ||G - Gfd|| = %g\n", (double)(diffnorm / PetscMax(hcnorm, fdnorm)), (double)diffnorm));
82   PetscCall(PetscViewerASCIIPrintf(viewer, "  max-norm ||G - Gfd||/||G|| = %g, ||G - Gfd|| = %g\n", (double)(diffmax / PetscMax(hcmax, fdmax)), (double)diffmax));
83 
84   if (complete_print) {
85     PetscCall(PetscViewerASCIIPrintf(viewer, "  Hand-coded gradient ----------\n"));
86     PetscCall(VecView(g1, mviewer));
87     PetscCall(PetscViewerASCIIPrintf(viewer, "  Finite difference gradient ----------\n"));
88     PetscCall(VecView(g2, mviewer));
89     PetscCall(PetscViewerASCIIPrintf(viewer, "  Hand-coded minus finite-difference gradient ----------\n"));
90     PetscCall(VecView(g3, mviewer));
91   }
92   PetscCall(VecDestroy(&g2));
93   PetscCall(VecDestroy(&g3));
94 
95   if (complete_print) {
96     PetscCall(PetscViewerPopFormat(mviewer));
97     PetscCall(PetscViewerDestroy(&mviewer));
98   }
99   PetscCall(PetscViewerASCIISetTab(viewer, tabs));
100   PetscFunctionReturn(PETSC_SUCCESS);
101 }
102 
103 /*@
104   TaoComputeGradient - Computes the gradient of the objective function
105 
106   Collective
107 
108   Input Parameters:
109 + tao - the `Tao` context
110 - X   - input vector
111 
112   Output Parameter:
113 . G - gradient vector
114 
115   Options Database Keys:
116 + -tao_test_gradient      - compare the user provided gradient with one compute via finite differences to check for errors
117 - -tao_test_gradient_view - display the user provided gradient, the finite difference gradient and the difference between them to help users detect the location of errors in the user provided gradient
118 
119   Level: developer
120 
121   Note:
122   `TaoComputeGradient()` is typically used within the implementation of the optimization method,
123   so most users would not generally call this routine themselves.
124 
125 .seealso: [](ch_tao), `TaoComputeObjective()`, `TaoComputeObjectiveAndGradient()`, `TaoSetGradient()`
126 @*/
TaoComputeGradient(Tao tao,Vec X,Vec G)127 PetscErrorCode TaoComputeGradient(Tao tao, Vec X, Vec G)
128 {
129   PetscReal dummy;
130 
131   PetscFunctionBegin;
132   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
133   PetscValidHeaderSpecific(X, VEC_CLASSID, 2);
134   PetscValidHeaderSpecific(G, VEC_CLASSID, 3);
135   PetscCheckSameComm(tao, 1, X, 2);
136   PetscCheckSameComm(tao, 1, G, 3);
137   PetscCall(VecLockReadPush(X));
138   if (tao->ops->computegradient) {
139     PetscCall(PetscLogEventBegin(TAO_GradientEval, tao, X, G, NULL));
140     PetscCallBack("Tao callback gradient", (*tao->ops->computegradient)(tao, X, G, tao->user_gradP));
141     PetscCall(PetscLogEventEnd(TAO_GradientEval, tao, X, G, NULL));
142     tao->ngrads++;
143   } else if (tao->ops->computeobjectiveandgradient) {
144     PetscCall(PetscLogEventBegin(TAO_ObjGradEval, tao, X, G, NULL));
145     PetscCallBack("Tao callback objective/gradient", (*tao->ops->computeobjectiveandgradient)(tao, X, &dummy, G, tao->user_objgradP));
146     PetscCall(PetscLogEventEnd(TAO_ObjGradEval, tao, X, G, NULL));
147     tao->nfuncgrads++;
148   } else SETERRQ(PetscObjectComm((PetscObject)tao), PETSC_ERR_ARG_WRONGSTATE, "TaoSetGradient() has not been called");
149   PetscCall(VecLockReadPop(X));
150 
151   PetscCall(TaoTestGradient(tao, X, G));
152   PetscFunctionReturn(PETSC_SUCCESS);
153 }
154 
155 /*@
156   TaoComputeObjective - Computes the objective function value at a given point
157 
158   Collective
159 
160   Input Parameters:
161 + tao - the `Tao` context
162 - X   - input vector
163 
164   Output Parameter:
165 . f - Objective value at X
166 
167   Level: developer
168 
169   Note:
170   `TaoComputeObjective()` is typically used within the implementation of the optimization algorithm
171   so most users would not generally call this routine themselves.
172 
173 .seealso: [](ch_tao), `Tao`, `TaoComputeGradient()`, `TaoComputeObjectiveAndGradient()`, `TaoSetObjective()`
174 @*/
TaoComputeObjective(Tao tao,Vec X,PetscReal * f)175 PetscErrorCode TaoComputeObjective(Tao tao, Vec X, PetscReal *f)
176 {
177   Vec temp;
178 
179   PetscFunctionBegin;
180   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
181   PetscValidHeaderSpecific(X, VEC_CLASSID, 2);
182   PetscCheckSameComm(tao, 1, X, 2);
183   PetscCall(VecLockReadPush(X));
184   if (tao->ops->computeobjective) {
185     PetscCall(PetscLogEventBegin(TAO_ObjectiveEval, tao, X, NULL, NULL));
186     PetscCallBack("Tao callback objective", (*tao->ops->computeobjective)(tao, X, f, tao->user_objP));
187     PetscCall(PetscLogEventEnd(TAO_ObjectiveEval, tao, X, NULL, NULL));
188     tao->nfuncs++;
189   } else if (tao->ops->computeobjectiveandgradient) {
190     PetscCall(PetscInfo(tao, "Duplicating variable vector in order to call func/grad routine\n"));
191     PetscCall(VecDuplicate(X, &temp));
192     PetscCall(PetscLogEventBegin(TAO_ObjGradEval, tao, X, NULL, NULL));
193     PetscCallBack("Tao callback objective/gradient", (*tao->ops->computeobjectiveandgradient)(tao, X, f, temp, tao->user_objgradP));
194     PetscCall(PetscLogEventEnd(TAO_ObjGradEval, tao, X, NULL, NULL));
195     PetscCall(VecDestroy(&temp));
196     tao->nfuncgrads++;
197   } else SETERRQ(PetscObjectComm((PetscObject)tao), PETSC_ERR_ARG_WRONGSTATE, "TaoSetObjective() has not been called");
198   PetscCall(PetscInfo(tao, "TAO Function evaluation: %20.19e\n", (double)(*f)));
199   PetscCall(VecLockReadPop(X));
200   PetscFunctionReturn(PETSC_SUCCESS);
201 }
202 
203 /*@
204   TaoComputeObjectiveAndGradient - Computes the objective function value at a given point
205 
206   Collective
207 
208   Input Parameters:
209 + tao - the `Tao` context
210 - X   - input vector
211 
212   Output Parameters:
213 + f - Objective value at `X`
214 - G - Gradient vector at `X`
215 
216   Level: developer
217 
218   Note:
219   `TaoComputeObjectiveAndGradient()` is typically used within the implementation of the optimization algorithm,
220   so most users would not generally call this routine themselves.
221 
222 .seealso: [](ch_tao), `TaoComputeGradient()`, `TaoSetObjective()`
223 @*/
TaoComputeObjectiveAndGradient(Tao tao,Vec X,PetscReal * f,Vec G)224 PetscErrorCode TaoComputeObjectiveAndGradient(Tao tao, Vec X, PetscReal *f, Vec G)
225 {
226   PetscFunctionBegin;
227   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
228   PetscValidHeaderSpecific(X, VEC_CLASSID, 2);
229   PetscValidHeaderSpecific(G, VEC_CLASSID, 4);
230   PetscCheckSameComm(tao, 1, X, 2);
231   PetscCheckSameComm(tao, 1, G, 4);
232   PetscCall(VecLockReadPush(X));
233   if (tao->ops->computeobjectiveandgradient) {
234     PetscCall(PetscLogEventBegin(TAO_ObjGradEval, tao, X, G, NULL));
235     if (tao->ops->computegradient == TaoDefaultComputeGradient) {
236       PetscCall(TaoComputeObjective(tao, X, f));
237       PetscCall(TaoDefaultComputeGradient(tao, X, G, NULL));
238     } else PetscCallBack("Tao callback objective/gradient", (*tao->ops->computeobjectiveandgradient)(tao, X, f, G, tao->user_objgradP));
239     PetscCall(PetscLogEventEnd(TAO_ObjGradEval, tao, X, G, NULL));
240     tao->nfuncgrads++;
241   } else if (tao->ops->computeobjective && tao->ops->computegradient) {
242     PetscCall(PetscLogEventBegin(TAO_ObjectiveEval, tao, X, NULL, NULL));
243     PetscCallBack("Tao callback objective", (*tao->ops->computeobjective)(tao, X, f, tao->user_objP));
244     PetscCall(PetscLogEventEnd(TAO_ObjectiveEval, tao, X, NULL, NULL));
245     tao->nfuncs++;
246     PetscCall(PetscLogEventBegin(TAO_GradientEval, tao, X, G, NULL));
247     PetscCallBack("Tao callback gradient", (*tao->ops->computegradient)(tao, X, G, tao->user_gradP));
248     PetscCall(PetscLogEventEnd(TAO_GradientEval, tao, X, G, NULL));
249     tao->ngrads++;
250   } else SETERRQ(PetscObjectComm((PetscObject)tao), PETSC_ERR_ARG_WRONGSTATE, "TaoSetObjective() or TaoSetGradient() not set");
251   PetscCall(PetscInfo(tao, "TAO Function evaluation: %20.19e\n", (double)(*f)));
252   PetscCall(VecLockReadPop(X));
253 
254   PetscCall(TaoTestGradient(tao, X, G));
255   PetscFunctionReturn(PETSC_SUCCESS);
256 }
257 
258 /*@C
259   TaoSetObjective - Sets the function evaluation routine for minimization
260 
261   Logically Collective
262 
263   Input Parameters:
264 + tao  - the `Tao` context
265 . func - the objective function
266 - ctx  - [optional] user-defined context for private data for the function evaluation
267         routine (may be `NULL`)
268 
269   Calling sequence of `func`:
270 + tao - the optimizer
271 . x   - input vector
272 . f   - function value
273 - ctx - [optional] user-defined function context
274 
275   Level: beginner
276 
277 .seealso: [](ch_tao), `TaoSetGradient()`, `TaoSetHessian()`, `TaoSetObjectiveAndGradient()`, `TaoGetObjective()`
278 @*/
TaoSetObjective(Tao tao,PetscErrorCode (* func)(Tao tao,Vec x,PetscReal * f,PetscCtx ctx),PetscCtx ctx)279 PetscErrorCode TaoSetObjective(Tao tao, PetscErrorCode (*func)(Tao tao, Vec x, PetscReal *f, PetscCtx ctx), PetscCtx ctx)
280 {
281   PetscFunctionBegin;
282   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
283   if (ctx) tao->user_objP = ctx;
284   if (func) tao->ops->computeobjective = func;
285   PetscFunctionReturn(PETSC_SUCCESS);
286 }
287 
288 /*@C
289   TaoGetObjective - Gets the function evaluation routine for the function to be minimized
290 
291   Not Collective
292 
293   Input Parameter:
294 . tao - the `Tao` context
295 
296   Output Parameters:
297 + func - the objective function
298 - ctx  - the user-defined context for private data for the function evaluation
299 
300   Calling sequence of `func`:
301 + tao - the optimizer
302 . x   - input vector
303 . f   - function value
304 - ctx - [optional] user-defined function context
305 
306   Level: beginner
307 
308 .seealso: [](ch_tao), `Tao`, `TaoSetGradient()`, `TaoSetHessian()`, `TaoSetObjective()`
309 @*/
TaoGetObjective(Tao tao,PetscErrorCode (** func)(Tao tao,Vec x,PetscReal * f,PetscCtx ctx),PetscCtxRt ctx)310 PetscErrorCode TaoGetObjective(Tao tao, PetscErrorCode (**func)(Tao tao, Vec x, PetscReal *f, PetscCtx ctx), PetscCtxRt ctx)
311 {
312   PetscFunctionBegin;
313   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
314   if (func) *func = tao->ops->computeobjective;
315   if (ctx) *(void **)ctx = tao->user_objP;
316   PetscFunctionReturn(PETSC_SUCCESS);
317 }
318 
319 /*@C
320   TaoSetResidualRoutine - Sets the residual evaluation routine for least-square applications
321 
322   Logically Collective
323 
324   Input Parameters:
325 + tao  - the `Tao` context
326 . res  - the residual vector
327 . func - the residual evaluation routine
328 - ctx  - [optional] user-defined context for private data for the function evaluation
329          routine (may be `NULL`)
330 
331   Calling sequence of `func`:
332 + tao - the optimizer
333 . x   - input vector
334 . res - function value vector
335 - ctx - [optional] user-defined function context
336 
337   Level: beginner
338 
339 .seealso: [](ch_tao), `Tao`, `TaoSetObjective()`, `TaoSetJacobianRoutine()`
340 @*/
TaoSetResidualRoutine(Tao tao,Vec res,PetscErrorCode (* func)(Tao tao,Vec x,Vec res,PetscCtx ctx),PetscCtx ctx)341 PetscErrorCode TaoSetResidualRoutine(Tao tao, Vec res, PetscErrorCode (*func)(Tao tao, Vec x, Vec res, PetscCtx ctx), PetscCtx ctx)
342 {
343   PetscFunctionBegin;
344   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
345   PetscValidHeaderSpecific(res, VEC_CLASSID, 2);
346   PetscCall(PetscObjectReference((PetscObject)res));
347   if (tao->ls_res) PetscCall(VecDestroy(&tao->ls_res));
348   tao->ls_res               = res;
349   tao->user_lsresP          = ctx;
350   tao->ops->computeresidual = func;
351   PetscFunctionReturn(PETSC_SUCCESS);
352 }
353 
354 /*@
355   TaoSetResidualWeights - Give weights for the residual values. A vector can be used if only diagonal terms are used, otherwise a matrix can be give.
356 
357   Collective
358 
359   Input Parameters:
360 + tao     - the `Tao` context
361 . sigma_v - vector of weights (diagonal terms only)
362 . n       - the number of weights (if using off-diagonal)
363 . rows    - index list of rows for `sigma_v`
364 . cols    - index list of columns for `sigma_v`
365 - vals    - array of weights
366 
367   Level: intermediate
368 
369   Notes:
370   If this function is not provided, or if `sigma_v` and `vals` are both `NULL`, then the
371   identity matrix will be used for weights.
372 
373   Either `sigma_v` or `vals` should be `NULL`
374 
375 .seealso: [](ch_tao), `Tao`, `TaoSetResidualRoutine()`
376 @*/
TaoSetResidualWeights(Tao tao,Vec sigma_v,PetscInt n,PetscInt * rows,PetscInt * cols,PetscReal * vals)377 PetscErrorCode TaoSetResidualWeights(Tao tao, Vec sigma_v, PetscInt n, PetscInt *rows, PetscInt *cols, PetscReal *vals)
378 {
379   PetscInt i;
380 
381   PetscFunctionBegin;
382   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
383   if (sigma_v) PetscValidHeaderSpecific(sigma_v, VEC_CLASSID, 2);
384   PetscCall(PetscObjectReference((PetscObject)sigma_v));
385   PetscCall(VecDestroy(&tao->res_weights_v));
386   tao->res_weights_v = sigma_v;
387   if (vals) {
388     PetscCall(PetscFree(tao->res_weights_rows));
389     PetscCall(PetscFree(tao->res_weights_cols));
390     PetscCall(PetscFree(tao->res_weights_w));
391     PetscCall(PetscMalloc1(n, &tao->res_weights_rows));
392     PetscCall(PetscMalloc1(n, &tao->res_weights_cols));
393     PetscCall(PetscMalloc1(n, &tao->res_weights_w));
394     tao->res_weights_n = n;
395     for (i = 0; i < n; i++) {
396       tao->res_weights_rows[i] = rows[i];
397       tao->res_weights_cols[i] = cols[i];
398       tao->res_weights_w[i]    = vals[i];
399     }
400   } else {
401     tao->res_weights_n    = 0;
402     tao->res_weights_rows = NULL;
403     tao->res_weights_cols = NULL;
404   }
405   PetscFunctionReturn(PETSC_SUCCESS);
406 }
407 
408 /*@
409   TaoComputeResidual - Computes a least-squares residual vector at a given point
410 
411   Collective
412 
413   Input Parameters:
414 + tao - the `Tao` context
415 - X   - input vector
416 
417   Output Parameter:
418 . F - Objective vector at `X`
419 
420   Level: advanced
421 
422   Notes:
423   `TaoComputeResidual()` is typically used within the implementation of the optimization algorithm,
424   so most users would not generally call this routine themselves.
425 
426 .seealso: [](ch_tao), `Tao`, `TaoSetResidualRoutine()`
427 @*/
TaoComputeResidual(Tao tao,Vec X,Vec F)428 PetscErrorCode TaoComputeResidual(Tao tao, Vec X, Vec F)
429 {
430   PetscFunctionBegin;
431   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
432   PetscValidHeaderSpecific(X, VEC_CLASSID, 2);
433   PetscValidHeaderSpecific(F, VEC_CLASSID, 3);
434   PetscCheckSameComm(tao, 1, X, 2);
435   PetscCheckSameComm(tao, 1, F, 3);
436   PetscCheck(tao->ops->computeresidual, PetscObjectComm((PetscObject)tao), PETSC_ERR_ARG_WRONGSTATE, "TaoSetResidualRoutine() has not been called");
437   PetscCall(PetscLogEventBegin(TAO_ObjectiveEval, tao, X, NULL, NULL));
438   PetscCallBack("Tao callback least-squares residual", (*tao->ops->computeresidual)(tao, X, F, tao->user_lsresP));
439   PetscCall(PetscLogEventEnd(TAO_ObjectiveEval, tao, X, NULL, NULL));
440   tao->nfuncs++;
441   PetscCall(PetscInfo(tao, "TAO least-squares residual evaluation.\n"));
442   PetscFunctionReturn(PETSC_SUCCESS);
443 }
444 
445 /*@C
446   TaoSetGradient - Sets the gradient evaluation routine for the function to be optimized
447 
448   Logically Collective
449 
450   Input Parameters:
451 + tao  - the `Tao` context
452 . g    - [optional] the vector to internally hold the gradient computation
453 . func - the gradient function
454 - ctx  - [optional] user-defined context for private data for the gradient evaluation
455         routine (may be `NULL`)
456 
457   Calling sequence of `func`:
458 + tao - the optimization solver
459 . x   - input vector
460 . g   - gradient value (output)
461 - ctx - [optional] user-defined function context
462 
463   Level: beginner
464 
465 .seealso: [](ch_tao), `Tao`, `TaoSolve()`, `TaoSetObjective()`, `TaoSetHessian()`, `TaoSetObjectiveAndGradient()`, `TaoGetGradient()`
466 @*/
TaoSetGradient(Tao tao,Vec g,PetscErrorCode (* func)(Tao tao,Vec x,Vec g,PetscCtx ctx),PetscCtx ctx)467 PetscErrorCode TaoSetGradient(Tao tao, Vec g, PetscErrorCode (*func)(Tao tao, Vec x, Vec g, PetscCtx ctx), PetscCtx ctx)
468 {
469   PetscFunctionBegin;
470   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
471   if (g) {
472     PetscValidHeaderSpecific(g, VEC_CLASSID, 2);
473     PetscCheckSameComm(tao, 1, g, 2);
474     PetscCall(PetscObjectReference((PetscObject)g));
475     PetscCall(VecDestroy(&tao->gradient));
476     tao->gradient = g;
477   }
478   if (func) tao->ops->computegradient = func;
479   if (ctx) tao->user_gradP = ctx;
480   PetscFunctionReturn(PETSC_SUCCESS);
481 }
482 
483 /*@C
484   TaoGetGradient - Gets the gradient evaluation routine for the function being optimized
485 
486   Not Collective
487 
488   Input Parameter:
489 . tao - the `Tao` context
490 
491   Output Parameters:
492 + g    - the vector to internally hold the gradient computation
493 . func - the gradient function
494 - ctx  - user-defined context for private data for the gradient evaluation routine
495 
496   Calling sequence of `func`:
497 + tao - the optimizer
498 . x   - input vector
499 . g   - gradient value (output)
500 - ctx - [optional] user-defined function context
501 
502   Level: beginner
503 
504 .seealso: [](ch_tao), `Tao`, `TaoSetObjective()`, `TaoSetHessian()`, `TaoSetObjectiveAndGradient()`, `TaoSetGradient()`
505 @*/
TaoGetGradient(Tao tao,Vec * g,PetscErrorCode (** func)(Tao tao,Vec x,Vec g,PetscCtx ctx),PetscCtxRt ctx)506 PetscErrorCode TaoGetGradient(Tao tao, Vec *g, PetscErrorCode (**func)(Tao tao, Vec x, Vec g, PetscCtx ctx), PetscCtxRt ctx)
507 {
508   PetscFunctionBegin;
509   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
510   if (g) *g = tao->gradient;
511   if (func) *func = tao->ops->computegradient;
512   if (ctx) *(void **)ctx = tao->user_gradP;
513   PetscFunctionReturn(PETSC_SUCCESS);
514 }
515 
516 /*@C
517   TaoSetObjectiveAndGradient - Sets a combined objective function and gradient evaluation routine for the function to be optimized
518 
519   Logically Collective
520 
521   Input Parameters:
522 + tao  - the `Tao` context
523 . g    - [optional] the vector to internally hold the gradient computation
524 . func - the gradient function
525 - ctx  - [optional] user-defined context for private data for the gradient evaluation
526         routine (may be `NULL`)
527 
528   Calling sequence of `func`:
529 + tao - the optimization object
530 . x   - input vector
531 . f   - objective value (output)
532 . g   - gradient value (output)
533 - ctx - [optional] user-defined function context
534 
535   Level: beginner
536 
537   Note:
538   For some optimization methods using a combined function can be more eifficient.
539 
540 .seealso: [](ch_tao), `Tao`, `TaoSolve()`, `TaoSetObjective()`, `TaoSetHessian()`, `TaoSetGradient()`, `TaoGetObjectiveAndGradient()`
541 @*/
TaoSetObjectiveAndGradient(Tao tao,Vec g,PetscErrorCode (* func)(Tao tao,Vec x,PetscReal * f,Vec g,PetscCtx ctx),PetscCtx ctx)542 PetscErrorCode TaoSetObjectiveAndGradient(Tao tao, Vec g, PetscErrorCode (*func)(Tao tao, Vec x, PetscReal *f, Vec g, PetscCtx ctx), PetscCtx ctx)
543 {
544   PetscFunctionBegin;
545   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
546   if (g) {
547     PetscValidHeaderSpecific(g, VEC_CLASSID, 2);
548     PetscCheckSameComm(tao, 1, g, 2);
549     PetscCall(PetscObjectReference((PetscObject)g));
550     PetscCall(VecDestroy(&tao->gradient));
551     tao->gradient = g;
552   }
553   if (ctx) tao->user_objgradP = ctx;
554   if (func) tao->ops->computeobjectiveandgradient = func;
555   PetscFunctionReturn(PETSC_SUCCESS);
556 }
557 
558 /*@C
559   TaoGetObjectiveAndGradient - Gets the combined objective function and gradient evaluation routine for the function to be optimized
560 
561   Not Collective
562 
563   Input Parameter:
564 . tao - the `Tao` context
565 
566   Output Parameters:
567 + g    - the vector to internally hold the gradient computation
568 . func - the gradient function
569 - ctx  - user-defined context for private data for the gradient evaluation routine
570 
571   Calling sequence of `func`:
572 + tao - the optimizer
573 . x   - input vector
574 . f   - objective value (output)
575 . g   - gradient value (output)
576 - ctx - [optional] user-defined function context
577 
578   Level: beginner
579 
580 .seealso: [](ch_tao), `Tao`, `TaoSolve()`, `TaoSetObjective()`, `TaoSetGradient()`, `TaoSetHessian()`, `TaoSetObjectiveAndGradient()`
581 @*/
TaoGetObjectiveAndGradient(Tao tao,Vec * g,PetscErrorCode (** func)(Tao tao,Vec x,PetscReal * f,Vec g,PetscCtx ctx),PetscCtxRt ctx)582 PetscErrorCode TaoGetObjectiveAndGradient(Tao tao, Vec *g, PetscErrorCode (**func)(Tao tao, Vec x, PetscReal *f, Vec g, PetscCtx ctx), PetscCtxRt ctx)
583 {
584   PetscFunctionBegin;
585   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
586   if (g) *g = tao->gradient;
587   if (func) *func = tao->ops->computeobjectiveandgradient;
588   if (ctx) *(void **)ctx = tao->user_objgradP;
589   PetscFunctionReturn(PETSC_SUCCESS);
590 }
591 
592 /*@
593   TaoIsObjectiveDefined - Checks to see if the user has
594   declared an objective-only routine.  Useful for determining when
595   it is appropriate to call `TaoComputeObjective()` or
596   `TaoComputeObjectiveAndGradient()`
597 
598   Not Collective
599 
600   Input Parameter:
601 . tao - the `Tao` context
602 
603   Output Parameter:
604 . flg - `PETSC_TRUE` if function routine is set by user, `PETSC_FALSE` otherwise
605 
606   Level: developer
607 
608 .seealso: [](ch_tao), `Tao`, `TaoSetObjective()`, `TaoIsGradientDefined()`, `TaoIsObjectiveAndGradientDefined()`
609 @*/
TaoIsObjectiveDefined(Tao tao,PetscBool * flg)610 PetscErrorCode TaoIsObjectiveDefined(Tao tao, PetscBool *flg)
611 {
612   PetscFunctionBegin;
613   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
614   if (tao->ops->computeobjective == NULL) *flg = PETSC_FALSE;
615   else *flg = PETSC_TRUE;
616   PetscFunctionReturn(PETSC_SUCCESS);
617 }
618 
619 /*@
620   TaoIsGradientDefined - Checks to see if the user has
621   declared an objective-only routine.  Useful for determining when
622   it is appropriate to call `TaoComputeGradient()` or
623   `TaoComputeGradientAndGradient()`
624 
625   Not Collective
626 
627   Input Parameter:
628 . tao - the `Tao` context
629 
630   Output Parameter:
631 . flg - `PETSC_TRUE` if function routine is set by user, `PETSC_FALSE` otherwise
632 
633   Level: developer
634 
635 .seealso: [](ch_tao), `TaoSetGradient()`, `TaoIsObjectiveDefined()`, `TaoIsObjectiveAndGradientDefined()`
636 @*/
TaoIsGradientDefined(Tao tao,PetscBool * flg)637 PetscErrorCode TaoIsGradientDefined(Tao tao, PetscBool *flg)
638 {
639   PetscFunctionBegin;
640   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
641   if (tao->ops->computegradient == NULL) *flg = PETSC_FALSE;
642   else *flg = PETSC_TRUE;
643   PetscFunctionReturn(PETSC_SUCCESS);
644 }
645 
646 /*@
647   TaoIsObjectiveAndGradientDefined - Checks to see if the user has
648   declared a joint objective/gradient routine.  Useful for determining when
649   it is appropriate to call `TaoComputeObjective()` or
650   `TaoComputeObjectiveAndGradient()`
651 
652   Not Collective
653 
654   Input Parameter:
655 . tao - the `Tao` context
656 
657   Output Parameter:
658 . flg - `PETSC_TRUE` if function routine is set by user, `PETSC_FALSE` otherwise
659 
660   Level: developer
661 
662 .seealso: [](ch_tao), `TaoSetObjectiveAndGradient()`, `TaoIsObjectiveDefined()`, `TaoIsGradientDefined()`
663 @*/
TaoIsObjectiveAndGradientDefined(Tao tao,PetscBool * flg)664 PetscErrorCode TaoIsObjectiveAndGradientDefined(Tao tao, PetscBool *flg)
665 {
666   PetscFunctionBegin;
667   PetscValidHeaderSpecific(tao, TAO_CLASSID, 1);
668   if (tao->ops->computeobjectiveandgradient == NULL) *flg = PETSC_FALSE;
669   else *flg = PETSC_TRUE;
670   PetscFunctionReturn(PETSC_SUCCESS);
671 }
672