xref: /petsc/src/tao/interface/taosolver.c (revision 8163d661aa87b439a7f7ec5244a491b3f217b110)
1 #define TAO_DLL
2 
3 #include <petsc/private/taoimpl.h> /*I "petsctao.h" I*/
4 
5 PetscBool TaoRegisterAllCalled = PETSC_FALSE;
6 PetscFunctionList TaoList = NULL;
7 
8 PetscClassId TAO_CLASSID;
9 PetscLogEvent Tao_Solve, Tao_ObjectiveEval, Tao_GradientEval, Tao_ObjGradientEval, Tao_HessianEval, Tao_ConstraintsEval, Tao_JacobianEval;
10 
11 const char *TaoSubSetTypes[] = {  "subvec","mask","matrixfree","TaoSubSetType","TAO_SUBSET_",0};
12 
13 #undef __FUNCT__
14 #define __FUNCT__ "TaoCreate"
15 /*@
16   TaoCreate - Creates a TAO solver
17 
18   Collective on MPI_Comm
19 
20   Input Parameter:
21 . comm - MPI communicator
22 
23   Output Parameter:
24 . newtao - the new Tao context
25 
26   Available methods include:
27 +    nls - Newton's method with line search for unconstrained minimization
28 .    ntr - Newton's method with trust region for unconstrained minimization
29 .    ntl - Newton's method with trust region, line search for unconstrained minimization
30 .    lmvm - Limited memory variable metric method for unconstrained minimization
31 .    cg - Nonlinear conjugate gradient method for unconstrained minimization
32 .    nm - Nelder-Mead algorithm for derivate-free unconstrained minimization
33 .    tron - Newton Trust Region method for bound constrained minimization
34 .    gpcg - Newton Trust Region method for quadratic bound constrained minimization
35 .    blmvm - Limited memory variable metric method for bound constrained minimization
36 .    lcl - Linearly constrained Lagrangian method for pde-constrained minimization
37 -    pounders - Model-based algorithm for nonlinear least squares
38 
39    Options Database Keys:
40 .   -tao_type - select which method TAO should use
41 
42    Level: beginner
43 
44 .seealso: TaoSolve(), TaoDestroy()
45 @*/
46 PetscErrorCode TaoCreate(MPI_Comm comm, Tao *newtao)
47 {
48   PetscErrorCode ierr;
49   Tao            tao;
50 
51   PetscFunctionBegin;
52   PetscValidPointer(newtao,2);
53   *newtao = NULL;
54 
55   ierr = TaoInitializePackage();CHKERRQ(ierr);
56   ierr = TaoLineSearchInitializePackage();CHKERRQ(ierr);
57 
58   ierr = PetscHeaderCreate(tao,TAO_CLASSID,"Tao","Optimization solver","Tao",comm,TaoDestroy,TaoView);CHKERRQ(ierr);
59   tao->ops->computeobjective=0;
60   tao->ops->computeobjectiveandgradient=0;
61   tao->ops->computegradient=0;
62   tao->ops->computehessian=0;
63   tao->ops->computeseparableobjective=0;
64   tao->ops->computeconstraints=0;
65   tao->ops->computejacobian=0;
66   tao->ops->computejacobianequality=0;
67   tao->ops->computejacobianinequality=0;
68   tao->ops->computeequalityconstraints=0;
69   tao->ops->computeinequalityconstraints=0;
70   tao->ops->convergencetest=TaoDefaultConvergenceTest;
71   tao->ops->convergencedestroy=0;
72   tao->ops->computedual=0;
73   tao->ops->setup=0;
74   tao->ops->solve=0;
75   tao->ops->view=0;
76   tao->ops->setfromoptions=0;
77   tao->ops->destroy=0;
78 
79   tao->solution=NULL;
80   tao->gradient=NULL;
81   tao->sep_objective = NULL;
82   tao->constraints=NULL;
83   tao->constraints_equality=NULL;
84   tao->constraints_inequality=NULL;
85   tao->stepdirection=NULL;
86   tao->niter=0;
87   tao->ntotalits=0;
88   tao->XL = NULL;
89   tao->XU = NULL;
90   tao->IL = NULL;
91   tao->IU = NULL;
92   tao->DI = NULL;
93   tao->DE = NULL;
94   tao->gradient_norm = NULL;
95   tao->gradient_norm_tmp = NULL;
96   tao->hessian = NULL;
97   tao->hessian_pre = NULL;
98   tao->jacobian = NULL;
99   tao->jacobian_pre = NULL;
100   tao->jacobian_state = NULL;
101   tao->jacobian_state_pre = NULL;
102   tao->jacobian_state_inv = NULL;
103   tao->jacobian_design = NULL;
104   tao->jacobian_design_pre = NULL;
105   tao->jacobian_equality = NULL;
106   tao->jacobian_equality_pre = NULL;
107   tao->jacobian_inequality = NULL;
108   tao->jacobian_inequality_pre = NULL;
109   tao->state_is = NULL;
110   tao->design_is = NULL;
111 
112   tao->max_it     = 10000;
113   tao->max_funcs   = 10000;
114 #if defined(PETSC_USE_REAL_SINGLE)
115   tao->fatol       = 1e-5;
116   tao->frtol       = 1e-5;
117   tao->gatol       = 1e-5;
118   tao->grtol       = 1e-5;
119 #else
120   tao->fatol       = 1e-8;
121   tao->frtol       = 1e-8;
122   tao->gatol       = 1e-8;
123   tao->grtol       = 1e-8;
124 #endif
125   tao->crtol       = 0.0;
126   tao->catol       = 0.0;
127   tao->steptol     = 0.0;
128   tao->gttol       = 0.0;
129   tao->trust0      = PETSC_INFINITY;
130   tao->fmin        = PETSC_NINFINITY;
131   tao->hist_malloc = PETSC_FALSE;
132   tao->hist_reset = PETSC_TRUE;
133   tao->hist_max = 0;
134   tao->hist_len = 0;
135   tao->hist_obj = NULL;
136   tao->hist_resid = NULL;
137   tao->hist_cnorm = NULL;
138   tao->hist_lits = NULL;
139 
140   tao->numbermonitors=0;
141   tao->viewsolution=PETSC_FALSE;
142   tao->viewhessian=PETSC_FALSE;
143   tao->viewgradient=PETSC_FALSE;
144   tao->viewjacobian=PETSC_FALSE;
145   tao->viewconstraints = PETSC_FALSE;
146 
147   /* These flags prevents algorithms from overriding user options */
148   tao->max_it_changed   =PETSC_FALSE;
149   tao->max_funcs_changed=PETSC_FALSE;
150   tao->fatol_changed    =PETSC_FALSE;
151   tao->frtol_changed    =PETSC_FALSE;
152   tao->gatol_changed    =PETSC_FALSE;
153   tao->grtol_changed    =PETSC_FALSE;
154   tao->gttol_changed    =PETSC_FALSE;
155   tao->steptol_changed  =PETSC_FALSE;
156   tao->trust0_changed   =PETSC_FALSE;
157   tao->fmin_changed     =PETSC_FALSE;
158   tao->catol_changed    =PETSC_FALSE;
159   tao->crtol_changed    =PETSC_FALSE;
160   ierr = TaoResetStatistics(tao);CHKERRQ(ierr);
161   *newtao = tao;
162   PetscFunctionReturn(0);
163 }
164 
165 #undef __FUNCT__
166 #define __FUNCT__ "TaoSolve"
167 /*@
168   TaoSolve - Solves an optimization problem min F(x) s.t. l <= x <= u
169 
170   Collective on Tao
171 
172   Input Parameters:
173 . tao - the Tao context
174 
175   Notes:
176   The user must set up the Tao with calls to TaoSetInitialVector(),
177   TaoSetObjectiveRoutine(),
178   TaoSetGradientRoutine(), and (if using 2nd order method) TaoSetHessianRoutine().
179 
180   Level: beginner
181 
182 .seealso: TaoCreate(), TaoSetObjectiveRoutine(), TaoSetGradientRoutine(), TaoSetHessianRoutine()
183  @*/
184 PetscErrorCode TaoSolve(Tao tao)
185 {
186   PetscErrorCode   ierr;
187   static PetscBool set = PETSC_FALSE;
188 
189   PetscFunctionBegin;
190   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
191   ierr = PetscCitationsRegister("@TechReport{tao-user-ref,\n"
192                                 "title   = {Toolkit for Advanced Optimization (TAO) Users Manual},\n"
193                                 "author  = {Todd Munson and Jason Sarich and Stefan Wild and Steve Benson and Lois Curfman McInnes},\n"
194                                 "Institution = {Argonne National Laboratory},\n"
195                                 "Year   = 2014,\n"
196                                 "Number = {ANL/MCS-TM-322 - Revision 3.5},\n"
197                                 "url    = {http://www.mcs.anl.gov/tao}\n}\n",&set);CHKERRQ(ierr);
198 
199   ierr = TaoSetUp(tao);CHKERRQ(ierr);
200   ierr = TaoResetStatistics(tao);CHKERRQ(ierr);
201   if (tao->linesearch) {
202     ierr = TaoLineSearchReset(tao->linesearch);CHKERRQ(ierr);
203   }
204 
205   ierr = PetscLogEventBegin(Tao_Solve,tao,0,0,0);CHKERRQ(ierr);
206   if (tao->ops->solve){ ierr = (*tao->ops->solve)(tao);CHKERRQ(ierr); }
207   ierr = PetscLogEventEnd(Tao_Solve,tao,0,0,0);CHKERRQ(ierr);
208 
209   tao->ntotalits += tao->niter;
210   ierr = TaoViewFromOptions(tao,NULL,"-tao_view");CHKERRQ(ierr);
211 
212   if (tao->printreason) {
213     if (tao->reason > 0) {
214       ierr = PetscPrintf(((PetscObject)tao)->comm,"TAO solve converged due to %s iterations %D\n",TaoConvergedReasons[tao->reason],tao->niter);CHKERRQ(ierr);
215     } else {
216       ierr = PetscPrintf(((PetscObject)tao)->comm,"TAO solve did not converge due to %s iteration %D\n",TaoConvergedReasons[tao->reason],tao->niter);CHKERRQ(ierr);
217     }
218   }
219   PetscFunctionReturn(0);
220 }
221 
222 #undef __FUNCT__
223 #define __FUNCT__ "TaoSetUp"
224 /*@
225   TaoSetUp - Sets up the internal data structures for the later use
226   of a Tao solver
227 
228   Collective on tao
229 
230   Input Parameters:
231 . tao - the TAO context
232 
233   Notes:
234   The user will not need to explicitly call TaoSetUp(), as it will
235   automatically be called in TaoSolve().  However, if the user
236   desires to call it explicitly, it should come after TaoCreate()
237   and any TaoSetSomething() routines, but before TaoSolve().
238 
239   Level: advanced
240 
241 .seealso: TaoCreate(), TaoSolve()
242 @*/
243 PetscErrorCode TaoSetUp(Tao tao)
244 {
245   PetscErrorCode ierr;
246 
247   PetscFunctionBegin;
248   PetscValidHeaderSpecific(tao, TAO_CLASSID,1);
249   if (tao->setupcalled) PetscFunctionReturn(0);
250 
251   if (!tao->solution) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call TaoSetInitialVector");
252   if (tao->ops->setup) {
253     ierr = (*tao->ops->setup)(tao);CHKERRQ(ierr);
254   }
255   tao->setupcalled = PETSC_TRUE;
256   PetscFunctionReturn(0);
257 }
258 
259 #undef __FUNCT__
260 #define __FUNCT__ "TaoDestroy"
261 /*@
262   TaoDestroy - Destroys the TAO context that was created with
263   TaoCreate()
264 
265   Collective on Tao
266 
267   Input Parameter:
268 . tao - the Tao context
269 
270   Level: beginner
271 
272 .seealso: TaoCreate(), TaoSolve()
273 @*/
274 PetscErrorCode TaoDestroy(Tao *tao)
275 {
276   PetscErrorCode ierr;
277 
278   PetscFunctionBegin;
279   if (!*tao) PetscFunctionReturn(0);
280   PetscValidHeaderSpecific(*tao,TAO_CLASSID,1);
281   if (--((PetscObject)*tao)->refct > 0) {*tao=0;PetscFunctionReturn(0);}
282 
283   if ((*tao)->ops->destroy) {
284     ierr = (*((*tao))->ops->destroy)(*tao);CHKERRQ(ierr);
285   }
286   ierr = KSPDestroy(&(*tao)->ksp);CHKERRQ(ierr);
287   ierr = TaoLineSearchDestroy(&(*tao)->linesearch);CHKERRQ(ierr);
288 
289   if ((*tao)->ops->convergencedestroy) {
290     ierr = (*(*tao)->ops->convergencedestroy)((*tao)->cnvP);CHKERRQ(ierr);
291     if ((*tao)->jacobian_state_inv) {
292       ierr = MatDestroy(&(*tao)->jacobian_state_inv);CHKERRQ(ierr);
293     }
294   }
295   ierr = VecDestroy(&(*tao)->solution);CHKERRQ(ierr);
296   ierr = VecDestroy(&(*tao)->gradient);CHKERRQ(ierr);
297 
298   if ((*tao)->gradient_norm) {
299     ierr = PetscObjectDereference((PetscObject)(*tao)->gradient_norm);CHKERRQ(ierr);
300     ierr = VecDestroy(&(*tao)->gradient_norm_tmp);CHKERRQ(ierr);
301   }
302 
303   ierr = VecDestroy(&(*tao)->XL);CHKERRQ(ierr);
304   ierr = VecDestroy(&(*tao)->XU);CHKERRQ(ierr);
305   ierr = VecDestroy(&(*tao)->IL);CHKERRQ(ierr);
306   ierr = VecDestroy(&(*tao)->IU);CHKERRQ(ierr);
307   ierr = VecDestroy(&(*tao)->DE);CHKERRQ(ierr);
308   ierr = VecDestroy(&(*tao)->DI);CHKERRQ(ierr);
309   ierr = VecDestroy(&(*tao)->constraints_equality);CHKERRQ(ierr);
310   ierr = VecDestroy(&(*tao)->constraints_inequality);CHKERRQ(ierr);
311   ierr = VecDestroy(&(*tao)->stepdirection);CHKERRQ(ierr);
312   ierr = MatDestroy(&(*tao)->hessian_pre);CHKERRQ(ierr);
313   ierr = MatDestroy(&(*tao)->hessian);CHKERRQ(ierr);
314   ierr = MatDestroy(&(*tao)->jacobian_pre);CHKERRQ(ierr);
315   ierr = MatDestroy(&(*tao)->jacobian);CHKERRQ(ierr);
316   ierr = MatDestroy(&(*tao)->jacobian_state_pre);CHKERRQ(ierr);
317   ierr = MatDestroy(&(*tao)->jacobian_state);CHKERRQ(ierr);
318   ierr = MatDestroy(&(*tao)->jacobian_state_inv);CHKERRQ(ierr);
319   ierr = MatDestroy(&(*tao)->jacobian_design);CHKERRQ(ierr);
320   ierr = MatDestroy(&(*tao)->jacobian_equality);CHKERRQ(ierr);
321   ierr = MatDestroy(&(*tao)->jacobian_equality_pre);CHKERRQ(ierr);
322   ierr = MatDestroy(&(*tao)->jacobian_inequality);CHKERRQ(ierr);
323   ierr = MatDestroy(&(*tao)->jacobian_inequality_pre);CHKERRQ(ierr);
324   ierr = ISDestroy(&(*tao)->state_is);CHKERRQ(ierr);
325   ierr = ISDestroy(&(*tao)->design_is);CHKERRQ(ierr);
326   ierr = TaoCancelMonitors(*tao);CHKERRQ(ierr);
327   if ((*tao)->hist_malloc) {
328     ierr = PetscFree((*tao)->hist_obj);CHKERRQ(ierr);
329     ierr = PetscFree((*tao)->hist_resid);CHKERRQ(ierr);
330     ierr = PetscFree((*tao)->hist_cnorm);CHKERRQ(ierr);
331     ierr = PetscFree((*tao)->hist_lits);CHKERRQ(ierr);
332   }
333   ierr = PetscHeaderDestroy(tao);CHKERRQ(ierr);
334   PetscFunctionReturn(0);
335 }
336 
337 #undef __FUNCT__
338 #define __FUNCT__ "TaoSetFromOptions"
339 /*@
340   TaoSetFromOptions - Sets various Tao parameters from user
341   options.
342 
343   Collective on Tao
344 
345   Input Paremeter:
346 . tao - the Tao solver context
347 
348   options Database Keys:
349 + -tao_type <type> - The algorithm that TAO uses (lmvm, nls, etc.)
350 . -tao_fatol <fatol> - absolute error tolerance in function value
351 . -tao_frtol <frtol> - relative error tolerance in function value
352 . -tao_gatol <gatol> - absolute error tolerance for ||gradient||
353 . -tao_grtol <grtol> - relative error tolerance for ||gradient||
354 . -tao_gttol <gttol> - reduction of ||gradient|| relative to initial gradient
355 . -tao_max_it <max> - sets maximum number of iterations
356 . -tao_max_funcs <max> - sets maximum number of function evaluations
357 . -tao_fmin <fmin> - stop if function value reaches fmin
358 . -tao_steptol <tol> - stop if trust region radius less than <tol>
359 . -tao_trust0 <t> - initial trust region radius
360 . -tao_monitor - prints function value and residual at each iteration
361 . -tao_smonitor - same as tao_monitor, but truncates very small values
362 . -tao_cmonitor - prints function value, residual, and constraint norm at each iteration
363 . -tao_view_solution - prints solution vector at each iteration
364 . -tao_view_separableobjective - prints separable objective vector at each iteration
365 . -tao_view_step - prints step direction vector at each iteration
366 . -tao_view_gradient - prints gradient vector at each iteration
367 . -tao_draw_solution - graphically view solution vector at each iteration
368 . -tao_draw_step - graphically view step vector at each iteration
369 . -tao_draw_gradient - graphically view gradient at each iteration
370 . -tao_fd_gradient - use gradient computed with finite differences
371 . -tao_cancelmonitors - cancels all monitors (except those set with command line)
372 . -tao_view - prints information about the Tao after solving
373 - -tao_converged_reason - prints the reason TAO stopped iterating
374 
375   Notes:
376   To see all options, run your program with the -help option or consult the
377   user's manual. Should be called after TaoCreate() but before TaoSolve()
378 
379   Level: beginner
380 @*/
381 PetscErrorCode TaoSetFromOptions(Tao tao)
382 {
383   PetscErrorCode ierr;
384   const TaoType  default_type = TAOLMVM;
385   const char     *prefix;
386   char           type[256], monfilename[PETSC_MAX_PATH_LEN];
387   PetscViewer    monviewer;
388   PetscBool      flg;
389   MPI_Comm       comm;
390 
391   PetscFunctionBegin;
392   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
393   ierr = PetscObjectGetComm((PetscObject)tao,&comm);CHKERRQ(ierr);
394   ierr = TaoGetOptionsPrefix(tao,&prefix);CHKERRQ(ierr);
395   /* So no warnings are given about unused options */
396   ierr = PetscOptionsHasName(prefix,"-tao_ls_type",&flg);CHKERRQ(ierr);
397 
398   ierr = PetscObjectOptionsBegin((PetscObject)tao);CHKERRQ(ierr);
399   {
400     ierr = TaoRegisterAll();CHKERRQ(ierr);
401     if (((PetscObject)tao)->type_name) {
402       default_type = ((PetscObject)tao)->type_name;
403     }
404     /* Check for type from options */
405     ierr = PetscOptionsFList("-tao_type","Tao Solver type","TaoSetType",TaoList,default_type,type,256,&flg);CHKERRQ(ierr);
406     if (flg) {
407       ierr = TaoSetType(tao,type);CHKERRQ(ierr);
408     } else if (!((PetscObject)tao)->type_name) {
409       ierr = TaoSetType(tao,default_type);CHKERRQ(ierr);
410     }
411 
412     ierr = PetscOptionsReal("-tao_fatol","Stop if solution within","TaoSetTolerances",tao->fatol,&tao->fatol,&flg);CHKERRQ(ierr);
413     if (flg) tao->fatol_changed=PETSC_TRUE;
414     ierr = PetscOptionsReal("-tao_frtol","Stop if relative solution within","TaoSetTolerances",tao->frtol,&tao->frtol,&flg);CHKERRQ(ierr);
415     if (flg) tao->frtol_changed=PETSC_TRUE;
416     ierr = PetscOptionsReal("-tao_catol","Stop if constraints violations within","TaoSetConstraintTolerances",tao->catol,&tao->catol,&flg);CHKERRQ(ierr);
417     if (flg) tao->catol_changed=PETSC_TRUE;
418     ierr = PetscOptionsReal("-tao_crtol","Stop if relative contraint violations within","TaoSetConstraintTolerances",tao->crtol,&tao->crtol,&flg);CHKERRQ(ierr);
419     if (flg) tao->crtol_changed=PETSC_TRUE;
420     ierr = PetscOptionsReal("-tao_gatol","Stop if norm of gradient less than","TaoSetTolerances",tao->gatol,&tao->gatol,&flg);CHKERRQ(ierr);
421     if (flg) tao->gatol_changed=PETSC_TRUE;
422     ierr = PetscOptionsReal("-tao_grtol","Stop if norm of gradient divided by the function value is less than","TaoSetTolerances",tao->grtol,&tao->grtol,&flg);CHKERRQ(ierr);
423     if (flg) tao->grtol_changed=PETSC_TRUE;
424     ierr = PetscOptionsReal("-tao_gttol","Stop if the norm of the gradient is less than the norm of the initial gradient times tol","TaoSetTolerances",tao->gttol,&tao->gttol,&flg);CHKERRQ(ierr);
425     if (flg) tao->gttol_changed=PETSC_TRUE;
426     ierr = PetscOptionsInt("-tao_max_it","Stop if iteration number exceeds","TaoSetMaximumIterations",tao->max_it,&tao->max_it,&flg);CHKERRQ(ierr);
427     if (flg) tao->max_it_changed=PETSC_TRUE;
428     ierr = PetscOptionsInt("-tao_max_funcs","Stop if number of function evaluations exceeds","TaoSetMaximumFunctionEvaluations",tao->max_funcs,&tao->max_funcs,&flg);CHKERRQ(ierr);
429     if (flg) tao->max_funcs_changed=PETSC_TRUE;
430     ierr = PetscOptionsReal("-tao_fmin","Stop if function less than","TaoSetFunctionLowerBound",tao->fmin,&tao->fmin,&flg);CHKERRQ(ierr);
431     if (flg) tao->fmin_changed=PETSC_TRUE;
432     ierr = PetscOptionsReal("-tao_steptol","Stop if step size or trust region radius less than","",tao->steptol,&tao->steptol,&flg);CHKERRQ(ierr);
433     if (flg) tao->steptol_changed=PETSC_TRUE;
434     ierr = PetscOptionsReal("-tao_trust0","Initial trust region radius","TaoSetTrustRegionRadius",tao->trust0,&tao->trust0,&flg);CHKERRQ(ierr);
435     if (flg) tao->trust0_changed=PETSC_TRUE;
436     ierr = PetscOptionsString("-tao_view_solution","view solution vector after each evaluation","TaoSetMonitor","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
437     if (flg) {
438       ierr = PetscViewerASCIIOpen(comm,monfilename,&monviewer);CHKERRQ(ierr);
439       ierr = TaoSetMonitor(tao,TaoSolutionMonitor,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
440     }
441 
442     ierr = PetscOptionsBool("-tao_converged_reason","Print reason for TAO converged","TaoSolve",tao->printreason,&tao->printreason,NULL);CHKERRQ(ierr);
443     ierr = PetscOptionsString("-tao_view_gradient","view gradient vector after each evaluation","TaoSetMonitor","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
444     if (flg) {
445       ierr = PetscViewerASCIIOpen(comm,monfilename,&monviewer);CHKERRQ(ierr);
446       ierr = TaoSetMonitor(tao,TaoGradientMonitor,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
447     }
448 
449     ierr = PetscOptionsString("-tao_view_stepdirection","view step direction vector after each iteration","TaoSetMonitor","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
450     if (flg) {
451       ierr = PetscViewerASCIIOpen(comm,monfilename,&monviewer);CHKERRQ(ierr);
452       ierr = TaoSetMonitor(tao,TaoStepDirectionMonitor,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
453     }
454 
455     ierr = PetscOptionsString("-tao_view_separableobjective","view separable objective vector after each evaluation","TaoSetMonitor","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
456     if (flg) {
457       ierr = PetscViewerASCIIOpen(comm,monfilename,&monviewer);CHKERRQ(ierr);
458       ierr = TaoSetMonitor(tao,TaoSeparableObjectiveMonitor,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
459     }
460 
461     ierr = PetscOptionsString("-tao_monitor","Use the default convergence monitor","TaoSetMonitor","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
462     if (flg) {
463       ierr = PetscViewerASCIIOpen(comm,monfilename,&monviewer);CHKERRQ(ierr);
464       ierr = TaoSetMonitor(tao,TaoDefaultMonitor,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
465     }
466 
467     ierr = PetscOptionsString("-tao_smonitor","Use the short convergence monitor","TaoSetMonitor","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
468     if (flg) {
469       ierr = PetscViewerASCIIOpen(comm,monfilename,&monviewer);CHKERRQ(ierr);
470       ierr = TaoSetMonitor(tao,TaoDefaultSMonitor,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
471     }
472 
473     ierr = PetscOptionsString("-tao_cmonitor","Use the default convergence monitor with constraint norm","TaoSetMonitor","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
474     if (flg) {
475       ierr = PetscViewerASCIIOpen(comm,monfilename,&monviewer);CHKERRQ(ierr);
476       ierr = TaoSetMonitor(tao,TaoDefaultCMonitor,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
477     }
478 
479 
480     flg = PETSC_FALSE;
481     ierr = PetscOptionsBool("-tao_cancelmonitors","cancel all monitors and call any registered destroy routines","TaoCancelMonitors",flg,&flg,NULL);CHKERRQ(ierr);
482     if (flg) {ierr = TaoCancelMonitors(tao);CHKERRQ(ierr);}
483 
484     flg = PETSC_FALSE;
485     ierr = PetscOptionsBool("-tao_draw_solution","Plot solution vector at each iteration","TaoSetMonitor",flg,&flg,NULL);CHKERRQ(ierr);
486     if (flg) {
487       ierr = TaoSetMonitor(tao,TaoDrawSolutionMonitor,NULL,NULL);CHKERRQ(ierr);
488     }
489 
490     flg = PETSC_FALSE;
491     ierr = PetscOptionsBool("-tao_draw_step","plots step direction at each iteration","TaoSetMonitor",flg,&flg,NULL);CHKERRQ(ierr);
492     if (flg) {
493       ierr = TaoSetMonitor(tao,TaoDrawStepMonitor,NULL,NULL);CHKERRQ(ierr);
494     }
495 
496     flg = PETSC_FALSE;
497     ierr = PetscOptionsBool("-tao_draw_gradient","plots gradient at each iteration","TaoSetMonitor",flg,&flg,NULL);CHKERRQ(ierr);
498     if (flg) {
499       ierr = TaoSetMonitor(tao,TaoDrawGradientMonitor,NULL,NULL);CHKERRQ(ierr);
500     }
501     flg = PETSC_FALSE;
502     ierr = PetscOptionsBool("-tao_fd_gradient","compute gradient using finite differences","TaoDefaultComputeGradient",flg,&flg,NULL);CHKERRQ(ierr);
503     if (flg) {
504       ierr = TaoSetGradientRoutine(tao,TaoDefaultComputeGradient,NULL);CHKERRQ(ierr);
505     }
506     ierr = PetscOptionsEnum("-tao_subset_type","subset type", "", TaoSubSetTypes,(PetscEnum)tao->subset_type, (PetscEnum*)&tao->subset_type, 0);CHKERRQ(ierr);
507 
508     if (tao->ops->setfromoptions) {
509       ierr = (*tao->ops->setfromoptions)(PetscOptionsObject,tao);CHKERRQ(ierr);
510     }
511   }
512   ierr = PetscOptionsEnd();CHKERRQ(ierr);
513   PetscFunctionReturn(0);
514 }
515 
516 #undef __FUNCT__
517 #define __FUNCT__ "TaoView"
518 /*@C
519   TaoView - Prints information about the Tao
520 
521   Collective on Tao
522 
523   InputParameters:
524 + tao - the Tao context
525 - viewer - visualization context
526 
527   Options Database Key:
528 . -tao_view - Calls TaoView() at the end of TaoSolve()
529 
530   Notes:
531   The available visualization contexts include
532 +     PETSC_VIEWER_STDOUT_SELF - standard output (default)
533 -     PETSC_VIEWER_STDOUT_WORLD - synchronized standard
534          output where only the first processor opens
535          the file.  All other processors send their
536          data to the first processor to print.
537 
538   Level: beginner
539 
540 .seealso: PetscViewerASCIIOpen()
541 @*/
542 PetscErrorCode TaoView(Tao tao, PetscViewer viewer)
543 {
544   PetscErrorCode      ierr;
545   PetscBool           isascii,isstring;
546   const TaoType type;
547 
548   PetscFunctionBegin;
549   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
550   if (!viewer) {
551     ierr = PetscViewerASCIIGetStdout(((PetscObject)tao)->comm,&viewer);CHKERRQ(ierr);
552   }
553   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2);
554   PetscCheckSameComm(tao,1,viewer,2);
555 
556   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&isascii);CHKERRQ(ierr);
557   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);CHKERRQ(ierr);
558   if (isascii) {
559     ierr = PetscObjectPrintClassNamePrefixType((PetscObject)tao,viewer);CHKERRQ(ierr);
560     ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
561 
562     if (tao->ops->view) {
563       ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
564       ierr = (*tao->ops->view)(tao,viewer);CHKERRQ(ierr);
565       ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
566     }
567     if (tao->linesearch) {
568       ierr = PetscObjectPrintClassNamePrefixType((PetscObject)(tao->linesearch),viewer);CHKERRQ(ierr);
569     }
570     if (tao->ksp) {
571       ierr = PetscObjectPrintClassNamePrefixType((PetscObject)(tao->ksp),viewer);CHKERRQ(ierr);
572       ierr = PetscViewerASCIIPrintf(viewer,"total KSP iterations: %D\n",tao->ksp_tot_its);CHKERRQ(ierr);
573     }
574     if (tao->XL || tao->XU) {
575       ierr = PetscViewerASCIIPrintf(viewer,"Active Set subset type: %s\n",TaoSubSetTypes[tao->subset_type]);CHKERRQ(ierr);
576     }
577 
578     ierr=PetscViewerASCIIPrintf(viewer,"convergence tolerances: fatol=%g,",(double)tao->fatol);CHKERRQ(ierr);
579     ierr=PetscViewerASCIIPrintf(viewer," frtol=%g\n",(double)tao->frtol);CHKERRQ(ierr);
580 
581     ierr=PetscViewerASCIIPrintf(viewer,"convergence tolerances: gatol=%g,",(double)tao->gatol);CHKERRQ(ierr);
582     ierr=PetscViewerASCIIPrintf(viewer," steptol=%g,",(double)tao->steptol);CHKERRQ(ierr);
583     ierr=PetscViewerASCIIPrintf(viewer," gttol=%g\n",(double)tao->gttol);CHKERRQ(ierr);
584 
585     ierr = PetscViewerASCIIPrintf(viewer,"Residual in Function/Gradient:=%g\n",(double)tao->residual);CHKERRQ(ierr);
586 
587     if (tao->cnorm>0 || tao->catol>0 || tao->crtol>0){
588       ierr=PetscViewerASCIIPrintf(viewer,"convergence tolerances:");CHKERRQ(ierr);
589       ierr=PetscViewerASCIIPrintf(viewer," catol=%g,",(double)tao->catol);CHKERRQ(ierr);
590       ierr=PetscViewerASCIIPrintf(viewer," crtol=%g\n",(double)tao->crtol);CHKERRQ(ierr);
591       ierr = PetscViewerASCIIPrintf(viewer,"Residual in Constraints:=%g\n",(double)tao->cnorm);CHKERRQ(ierr);
592     }
593 
594     if (tao->trust < tao->steptol){
595       ierr=PetscViewerASCIIPrintf(viewer,"convergence tolerances: steptol=%g\n",(double)tao->steptol);CHKERRQ(ierr);
596       ierr=PetscViewerASCIIPrintf(viewer,"Final trust region radius:=%g\n",(double)tao->trust);CHKERRQ(ierr);
597     }
598 
599     if (tao->fmin>-1.e25){
600       ierr=PetscViewerASCIIPrintf(viewer,"convergence tolerances: function minimum=%g\n",(double)tao->fmin);CHKERRQ(ierr);
601     }
602     ierr = PetscViewerASCIIPrintf(viewer,"Objective value=%g\n",(double)tao->fc);CHKERRQ(ierr);
603 
604     ierr = PetscViewerASCIIPrintf(viewer,"total number of iterations=%D,          ",tao->niter);CHKERRQ(ierr);
605     ierr = PetscViewerASCIIPrintf(viewer,"              (max: %D)\n",tao->max_it);CHKERRQ(ierr);
606 
607     if (tao->nfuncs>0){
608       ierr = PetscViewerASCIIPrintf(viewer,"total number of function evaluations=%D,",tao->nfuncs);CHKERRQ(ierr);
609       ierr = PetscViewerASCIIPrintf(viewer,"                max: %D\n",tao->max_funcs);CHKERRQ(ierr);
610     }
611     if (tao->ngrads>0){
612       ierr = PetscViewerASCIIPrintf(viewer,"total number of gradient evaluations=%D,",tao->ngrads);CHKERRQ(ierr);
613       ierr = PetscViewerASCIIPrintf(viewer,"                max: %D\n",tao->max_funcs);CHKERRQ(ierr);
614     }
615     if (tao->nfuncgrads>0){
616       ierr = PetscViewerASCIIPrintf(viewer,"total number of function/gradient evaluations=%D,",tao->nfuncgrads);CHKERRQ(ierr);
617       ierr = PetscViewerASCIIPrintf(viewer,"    (max: %D)\n",tao->max_funcs);CHKERRQ(ierr);
618     }
619     if (tao->nhess>0){
620       ierr = PetscViewerASCIIPrintf(viewer,"total number of Hessian evaluations=%D\n",tao->nhess);CHKERRQ(ierr);
621     }
622     /*  if (tao->linear_its>0){
623      ierr = PetscViewerASCIIPrintf(viewer,"  total Krylov method iterations=%D\n",tao->linear_its);CHKERRQ(ierr);
624      }*/
625     if (tao->nconstraints>0){
626       ierr = PetscViewerASCIIPrintf(viewer,"total number of constraint function evaluations=%D\n",tao->nconstraints);CHKERRQ(ierr);
627     }
628     if (tao->njac>0){
629       ierr = PetscViewerASCIIPrintf(viewer,"total number of Jacobian evaluations=%D\n",tao->njac);CHKERRQ(ierr);
630     }
631 
632     if (tao->reason>0){
633       ierr = PetscViewerASCIIPrintf(viewer,    "Solution converged: ");CHKERRQ(ierr);
634       switch (tao->reason) {
635       case TAO_CONVERGED_FATOL:
636         ierr = PetscViewerASCIIPrintf(viewer,"estimated f(x)-f(X*) <= fatol\n");CHKERRQ(ierr);
637         break;
638       case TAO_CONVERGED_FRTOL:
639         ierr = PetscViewerASCIIPrintf(viewer,"estimated |f(x)-f(X*)|/|f(X*)| <= frtol\n");CHKERRQ(ierr);
640         break;
641       case TAO_CONVERGED_GATOL:
642         ierr = PetscViewerASCIIPrintf(viewer," ||g(X)|| <= gatol\n");CHKERRQ(ierr);
643         break;
644       case TAO_CONVERGED_GRTOL:
645         ierr = PetscViewerASCIIPrintf(viewer," ||g(X)||/|f(X)| <= grtol\n");CHKERRQ(ierr);
646         break;
647       case TAO_CONVERGED_GTTOL:
648         ierr = PetscViewerASCIIPrintf(viewer," ||g(X)||/||g(X0)|| <= gttol\n");CHKERRQ(ierr);
649         break;
650       case TAO_CONVERGED_STEPTOL:
651         ierr = PetscViewerASCIIPrintf(viewer," Steptol -- step size small\n");CHKERRQ(ierr);
652         break;
653       case TAO_CONVERGED_MINF:
654         ierr = PetscViewerASCIIPrintf(viewer," Minf --  f < fmin\n");CHKERRQ(ierr);
655         break;
656       case TAO_CONVERGED_USER:
657         ierr = PetscViewerASCIIPrintf(viewer," User Terminated\n");CHKERRQ(ierr);
658         break;
659       default:
660         ierr = PetscViewerASCIIPrintf(viewer,"\n");CHKERRQ(ierr);
661         break;
662       }
663 
664     } else {
665       ierr = PetscViewerASCIIPrintf(viewer,"Solver terminated: %D",tao->reason);CHKERRQ(ierr);
666       switch (tao->reason) {
667       case TAO_DIVERGED_MAXITS:
668         ierr = PetscViewerASCIIPrintf(viewer," Maximum Iterations\n");CHKERRQ(ierr);
669         break;
670       case TAO_DIVERGED_NAN:
671         ierr = PetscViewerASCIIPrintf(viewer," NAN or Inf encountered\n");CHKERRQ(ierr);
672         break;
673       case TAO_DIVERGED_MAXFCN:
674         ierr = PetscViewerASCIIPrintf(viewer," Maximum Function Evaluations\n");CHKERRQ(ierr);
675         break;
676       case TAO_DIVERGED_LS_FAILURE:
677         ierr = PetscViewerASCIIPrintf(viewer," Line Search Failure\n");CHKERRQ(ierr);
678         break;
679       case TAO_DIVERGED_TR_REDUCTION:
680         ierr = PetscViewerASCIIPrintf(viewer," Trust Region too small\n");CHKERRQ(ierr);
681         break;
682       case TAO_DIVERGED_USER:
683         ierr = PetscViewerASCIIPrintf(viewer," User Terminated\n");CHKERRQ(ierr);
684         break;
685       default:
686         ierr = PetscViewerASCIIPrintf(viewer,"\n");CHKERRQ(ierr);
687         break;
688       }
689     }
690     ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
691   } else if (isstring) {
692     ierr = TaoGetType(tao,&type);CHKERRQ(ierr);
693     ierr = PetscViewerStringSPrintf(viewer," %-3.3s",type);CHKERRQ(ierr);
694   }
695   PetscFunctionReturn(0);
696 }
697 
698 #undef __FUNCT__
699 #define __FUNCT__ "TaoSetTolerances"
700 /*@
701   TaoSetTolerances - Sets parameters used in TAO convergence tests
702 
703   Logically collective on Tao
704 
705   Input Parameters:
706 + tao - the Tao context
707 . fatol - absolute convergence tolerance
708 . frtol - relative convergence tolerance
709 . gatol - stop if norm of gradient is less than this
710 . grtol - stop if relative norm of gradient is less than this
711 - gttol - stop if norm of gradient is reduced by this factor
712 
713   Options Database Keys:
714 + -tao_fatol <fatol> - Sets fatol
715 . -tao_frtol <frtol> - Sets frtol
716 . -tao_gatol <gatol> - Sets gatol
717 . -tao_grtol <grtol> - Sets grtol
718 - -tao_gttol <gttol> - Sets gttol
719 
720   Stopping Criteria:
721 $ f(X) - f(X*) (estimated)            <= fatol
722 $ |f(X) - f(X*)| (estimated) / |f(X)| <= frtol
723 $ ||g(X)||                            <= gatol
724 $ ||g(X)|| / |f(X)|                   <= grtol
725 $ ||g(X)|| / ||g(X0)||                <= gttol
726 
727   Notes:
728   Use PETSC_DEFAULT to leave one or more tolerances unchanged.
729 
730   Level: beginner
731 
732 .seealso: TaoGetTolerances()
733 
734 @*/
735 PetscErrorCode TaoSetTolerances(Tao tao, PetscReal fatol, PetscReal frtol, PetscReal gatol, PetscReal grtol, PetscReal gttol)
736 {
737   PetscErrorCode ierr;
738 
739   PetscFunctionBegin;
740   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
741 
742   if (fatol != PETSC_DEFAULT) {
743     if (fatol<0) {
744       ierr = PetscInfo(tao,"Tried to set negative fatol -- ignored.\n");CHKERRQ(ierr);
745     } else {
746       tao->fatol = PetscMax(0,fatol);
747       tao->fatol_changed=PETSC_TRUE;
748     }
749   }
750   if (frtol != PETSC_DEFAULT) {
751     if (frtol<0) {
752       ierr = PetscInfo(tao,"Tried to set negative frtol -- ignored.\n");CHKERRQ(ierr);
753     } else {
754       tao->frtol = PetscMax(0,frtol);
755       tao->frtol_changed=PETSC_TRUE;
756     }
757   }
758 
759   if (gatol != PETSC_DEFAULT) {
760     if (gatol<0) {
761       ierr = PetscInfo(tao,"Tried to set negative gatol -- ignored.\n");CHKERRQ(ierr);
762     } else {
763       tao->gatol = PetscMax(0,gatol);
764       tao->gatol_changed=PETSC_TRUE;
765     }
766   }
767 
768   if (grtol != PETSC_DEFAULT) {
769     if (grtol<0) {
770       ierr = PetscInfo(tao,"Tried to set negative grtol -- ignored.\n");CHKERRQ(ierr);
771     } else {
772       tao->grtol = PetscMax(0,grtol);
773       tao->grtol_changed=PETSC_TRUE;
774     }
775   }
776 
777   if (gttol != PETSC_DEFAULT) {
778     if (gttol<0) {
779       ierr = PetscInfo(tao,"Tried to set negative gttol -- ignored.\n");CHKERRQ(ierr);
780     } else {
781       tao->gttol = PetscMax(0,gttol);
782       tao->gttol_changed=PETSC_TRUE;
783     }
784   }
785   PetscFunctionReturn(0);
786 }
787 
788 #undef __FUNCT__
789 #define __FUNCT__ "TaoSetConstraintTolerances"
790 /*@
791   TaoSetConstraintTolerances - Sets constraint tolerance parameters used in TAO  convergence tests
792 
793   Logically collective on Tao
794 
795   Input Parameters:
796 + tao - the Tao context
797 . catol - absolute constraint tolerance, constraint norm must be less than catol for used for fatol, gatol convergence criteria
798 - crtol - relative contraint tolerance, constraint norm must be less than crtol for used for fatol, gatol, gttol convergence criteria
799 
800   Options Database Keys:
801 + -tao_catol <catol> - Sets catol
802 - -tao_crtol <crtol> - Sets crtol
803 
804   Notes:
805   Use PETSC_DEFAULT to leave any tolerance unchanged.
806 
807   Level: intermediate
808 
809 .seealso: TaoGetTolerances(), TaoGetConstraintTolerances(), TaoSetTolerances()
810 
811 @*/
812 PetscErrorCode TaoSetConstraintTolerances(Tao tao, PetscReal catol, PetscReal crtol)
813 {
814   PetscErrorCode ierr;
815 
816   PetscFunctionBegin;
817   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
818 
819   if (catol != PETSC_DEFAULT) {
820     if (catol<0) {
821       ierr = PetscInfo(tao,"Tried to set negative catol -- ignored.\n");CHKERRQ(ierr);
822     } else {
823       tao->catol = PetscMax(0,catol);
824       tao->catol_changed=PETSC_TRUE;
825     }
826   }
827 
828   if (crtol != PETSC_DEFAULT) {
829     if (crtol<0) {
830       ierr = PetscInfo(tao,"Tried to set negative crtol -- ignored.\n");CHKERRQ(ierr);
831     } else {
832       tao->crtol = PetscMax(0,crtol);
833       tao->crtol_changed=PETSC_TRUE;
834     }
835   }
836   PetscFunctionReturn(0);
837 }
838 
839 #undef __FUNCT__
840 #define __FUNCT__ "TaoGetConstraintTolerances"
841 /*@
842   TaoGetConstraintTolerances - Gets constraint tolerance parameters used in TAO  convergence tests
843 
844   Not ollective
845 
846   Input Parameter:
847 . tao - the Tao context
848 
849   Output Parameter:
850 + catol - absolute constraint tolerance, constraint norm must be less than catol for used for fatol, gatol convergence criteria
851 - crtol - relative contraint tolerance, constraint norm must be less than crtol for used for fatol, gatol, gttol convergence criteria
852 
853   Level: intermediate
854 
855 .seealso: TaoGetTolerances(), TaoSetTolerances(), TaoSetConstraintTolerances()
856 
857 @*/
858 PetscErrorCode TaoGetConstraintTolerances(Tao tao, PetscReal *catol, PetscReal *crtol)
859 {
860   PetscFunctionBegin;
861   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
862   if (catol) *catol = tao->catol;
863   if (crtol) *crtol = tao->crtol;
864   PetscFunctionReturn(0);
865 }
866 
867 #undef __FUNCT__
868 #define __FUNCT__ "TaoSetFunctionLowerBound"
869 /*@
870    TaoSetFunctionLowerBound - Sets a bound on the solution objective value.
871    When an approximate solution with an objective value below this number
872    has been found, the solver will terminate.
873 
874    Logically Collective on Tao
875 
876    Input Parameters:
877 +  tao - the Tao solver context
878 -  fmin - the tolerance
879 
880    Options Database Keys:
881 .    -tao_fmin <fmin> - sets the minimum function value
882 
883    Level: intermediate
884 
885 .seealso: TaoSetTolerances()
886 @*/
887 PetscErrorCode TaoSetFunctionLowerBound(Tao tao,PetscReal fmin)
888 {
889   PetscFunctionBegin;
890   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
891   tao->fmin = fmin;
892   tao->fmin_changed=PETSC_TRUE;
893   PetscFunctionReturn(0);
894 }
895 
896 #undef __FUNCT__
897 #define __FUNCT__ "TaoGetFunctionLowerBound"
898 /*@
899    TaoGetFunctionLowerBound - Sets a bound on the solution objective value.
900    When an approximate solution with an objective value below this number
901    has been found, the solver will terminate.
902 
903    Not collective on Tao
904 
905    Input Parameters:
906 .  tao - the Tao solver context
907 
908    OutputParameters:
909 .  fmin - the minimum function value
910 
911    Level: intermediate
912 
913 .seealso: TaoSetFunctionLowerBound()
914 @*/
915 PetscErrorCode TaoGetFunctionLowerBound(Tao tao,PetscReal *fmin)
916 {
917   PetscFunctionBegin;
918   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
919   *fmin = tao->fmin;
920   PetscFunctionReturn(0);
921 }
922 
923 #undef __FUNCT__
924 #define __FUNCT__ "TaoSetMaximumFunctionEvaluations"
925 /*@
926    TaoSetMaximumFunctionEvaluations - Sets a maximum number of
927    function evaluations.
928 
929    Logically Collective on Tao
930 
931    Input Parameters:
932 +  tao - the Tao solver context
933 -  nfcn - the maximum number of function evaluations (>=0)
934 
935    Options Database Keys:
936 .    -tao_max_funcs <nfcn> - sets the maximum number of function evaluations
937 
938    Level: intermediate
939 
940 .seealso: TaoSetTolerances(), TaoSetMaximumIterations()
941 @*/
942 
943 PetscErrorCode TaoSetMaximumFunctionEvaluations(Tao tao,PetscInt nfcn)
944 {
945   PetscFunctionBegin;
946   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
947   tao->max_funcs = PetscMax(0,nfcn);
948   tao->max_funcs_changed=PETSC_TRUE;
949   PetscFunctionReturn(0);
950 }
951 
952 #undef __FUNCT__
953 #define __FUNCT__ "TaoGetMaximumFunctionEvaluations"
954 /*@
955    TaoGetMaximumFunctionEvaluations - Sets a maximum number of
956    function evaluations.
957 
958    Not Collective
959 
960    Input Parameters:
961 .  tao - the Tao solver context
962 
963    Output Parameters:
964 .  nfcn - the maximum number of function evaluations
965 
966    Level: intermediate
967 
968 .seealso: TaoSetMaximumFunctionEvaluations(), TaoGetMaximumIterations()
969 @*/
970 
971 PetscErrorCode TaoGetMaximumFunctionEvaluations(Tao tao,PetscInt *nfcn)
972 {
973   PetscFunctionBegin;
974   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
975   *nfcn = tao->max_funcs;
976   PetscFunctionReturn(0);
977 }
978 
979 #undef __FUNCT__
980 #define __FUNCT__ "TaoGetCurrentFunctionEvaluations"
981 /*@
982    TaoGetCurrentFunctionEvaluations - Get current number of
983    function evaluations.
984 
985    Not Collective
986 
987    Input Parameters:
988 .  tao - the Tao solver context
989 
990    Output Parameters:
991 .  nfuncs - the current number of function evaluations
992 
993    Level: intermediate
994 
995 .seealso: TaoSetMaximumFunctionEvaluations(), TaoGetMaximumFunctionEvaluations(), TaoGetMaximumIterations()
996 @*/
997 
998 PetscErrorCode TaoGetCurrentFunctionEvaluations(Tao tao,PetscInt *nfuncs)
999 {
1000   PetscFunctionBegin;
1001   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1002   *nfuncs=PetscMax(tao->nfuncs,tao->nfuncgrads);
1003   PetscFunctionReturn(0);
1004 }
1005 
1006 #undef __FUNCT__
1007 #define __FUNCT__ "TaoSetMaximumIterations"
1008 /*@
1009    TaoSetMaximumIterations - Sets a maximum number of iterates.
1010 
1011    Logically Collective on Tao
1012 
1013    Input Parameters:
1014 +  tao - the Tao solver context
1015 -  maxits - the maximum number of iterates (>=0)
1016 
1017    Options Database Keys:
1018 .    -tao_max_it <its> - sets the maximum number of iterations
1019 
1020    Level: intermediate
1021 
1022 .seealso: TaoSetTolerances(), TaoSetMaximumFunctionEvaluations()
1023 @*/
1024 PetscErrorCode TaoSetMaximumIterations(Tao tao,PetscInt maxits)
1025 {
1026   PetscFunctionBegin;
1027   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1028   tao->max_it = PetscMax(0,maxits);
1029   tao->max_it_changed=PETSC_TRUE;
1030   PetscFunctionReturn(0);
1031 }
1032 
1033 #undef __FUNCT__
1034 #define __FUNCT__ "TaoGetMaximumIterations"
1035 /*@
1036    TaoGetMaximumIterations - Sets a maximum number of iterates.
1037 
1038    Not Collective
1039 
1040    Input Parameters:
1041 .  tao - the Tao solver context
1042 
1043    Output Parameters:
1044 .  maxits - the maximum number of iterates
1045 
1046    Level: intermediate
1047 
1048 .seealso: TaoSetMaximumIterations(), TaoGetMaximumFunctionEvaluations()
1049 @*/
1050 PetscErrorCode TaoGetMaximumIterations(Tao tao,PetscInt *maxits)
1051 {
1052   PetscFunctionBegin;
1053   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1054   *maxits = tao->max_it;
1055   PetscFunctionReturn(0);
1056 }
1057 
1058 #undef __FUNCT__
1059 #define __FUNCT__ "TaoSetInitialTrustRegionRadius"
1060 /*@
1061    TaoSetInitialTrustRegionRadius - Sets the initial trust region radius.
1062 
1063    Logically collective on Tao
1064 
1065    Input Parameter:
1066 +  tao - a TAO optimization solver
1067 -  radius - the trust region radius
1068 
1069    Level: intermediate
1070 
1071    Options Database Key:
1072 .  -tao_trust0 <t0> - sets initial trust region radius
1073 
1074 .seealso: TaoGetTrustRegionRadius(), TaoSetTrustRegionTolerance()
1075 @*/
1076 PetscErrorCode TaoSetInitialTrustRegionRadius(Tao tao, PetscReal radius)
1077 {
1078   PetscFunctionBegin;
1079   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1080   tao->trust0 = PetscMax(0.0,radius);
1081   tao->trust0_changed=PETSC_TRUE;
1082   PetscFunctionReturn(0);
1083 }
1084 
1085 #undef __FUNCT__
1086 #define __FUNCT__ "TaoGetInitialTrustRegionRadius"
1087 /*@
1088    TaoGetInitialTrustRegionRadius - Sets the initial trust region radius.
1089 
1090    Not Collective
1091 
1092    Input Parameter:
1093 .  tao - a TAO optimization solver
1094 
1095    Output Parameter:
1096 .  radius - the trust region radius
1097 
1098    Level: intermediate
1099 
1100 .seealso: TaoSetInitialTrustRegionRadius(), TaoGetCurrentTrustRegionRadius()
1101 @*/
1102 PetscErrorCode TaoGetInitialTrustRegionRadius(Tao tao, PetscReal *radius)
1103 {
1104   PetscFunctionBegin;
1105   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1106   *radius = tao->trust0;
1107   PetscFunctionReturn(0);
1108 }
1109 
1110 #undef __FUNCT__
1111 #define __FUNCT__ "TaoGetCurrentTrustRegionRadius"
1112 /*@
1113    TaoGetCurrentTrustRegionRadius - Gets the current trust region radius.
1114 
1115    Not Collective
1116 
1117    Input Parameter:
1118 .  tao - a TAO optimization solver
1119 
1120    Output Parameter:
1121 .  radius - the trust region radius
1122 
1123    Level: intermediate
1124 
1125 .seealso: TaoSetInitialTrustRegionRadius(), TaoGetInitialTrustRegionRadius()
1126 @*/
1127 PetscErrorCode TaoGetCurrentTrustRegionRadius(Tao tao, PetscReal *radius)
1128 {
1129   PetscFunctionBegin;
1130   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1131   *radius = tao->trust;
1132   PetscFunctionReturn(0);
1133 }
1134 
1135 #undef __FUNCT__
1136 #define __FUNCT__ "TaoGetTolerances"
1137 /*@
1138   TaoGetTolerances - gets the current values of tolerances
1139 
1140   Not Collective
1141 
1142   Input Parameters:
1143 . tao - the Tao context
1144 
1145   Output Parameters:
1146 + fatol - absolute convergence tolerance
1147 . frtol - relative convergence tolerance
1148 . gatol - stop if norm of gradient is less than this
1149 . grtol - stop if relative norm of gradient is less than this
1150 - gttol - stop if norm of gradient is reduced by a this factor
1151 
1152   Note: NULL can be used as an argument if not all tolerances values are needed
1153 
1154 .seealso TaoSetTolerances()
1155 
1156   Level: intermediate
1157 @*/
1158 PetscErrorCode TaoGetTolerances(Tao tao, PetscReal *fatol, PetscReal *frtol, PetscReal *gatol, PetscReal *grtol, PetscReal *gttol)
1159 {
1160   PetscFunctionBegin;
1161   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1162   if (fatol) *fatol=tao->fatol;
1163   if (frtol) *frtol=tao->frtol;
1164   if (gatol) *gatol=tao->gatol;
1165   if (grtol) *grtol=tao->grtol;
1166   if (gttol) *gttol=tao->gttol;
1167   PetscFunctionReturn(0);
1168 }
1169 
1170 #undef __FUNCT__
1171 #define __FUNCT__ "TaoGetKSP"
1172 /*@
1173   TaoGetKSP - Gets the linear solver used by the optimization solver.
1174   Application writers should use TaoGetKSP if they need direct access
1175   to the PETSc KSP object.
1176 
1177   Not Collective
1178 
1179    Input Parameters:
1180 .  tao - the TAO solver
1181 
1182    Output Parameters:
1183 .  ksp - the KSP linear solver used in the optimization solver
1184 
1185    Level: intermediate
1186 
1187 @*/
1188 PetscErrorCode TaoGetKSP(Tao tao, KSP *ksp)
1189 {
1190   PetscFunctionBegin;
1191   *ksp = tao->ksp;
1192   PetscFunctionReturn(0);
1193 }
1194 
1195 #undef __FUNCT__
1196 #define __FUNCT__ "TaoGetLinearSolveIterations"
1197 /*@
1198    TaoGetLinearSolveIterations - Gets the total number of linear iterations
1199    used by the TAO solver
1200 
1201    Not Collective
1202 
1203    Input Parameter:
1204 .  tao - TAO context
1205 
1206    Output Parameter:
1207 .  lits - number of linear iterations
1208 
1209    Notes:
1210    This counter is reset to zero for each successive call to TaoSolve()
1211 
1212    Level: intermediate
1213 
1214 .keywords: TAO
1215 
1216 .seealso:  TaoGetKSP()
1217 @*/
1218 PetscErrorCode  TaoGetLinearSolveIterations(Tao tao,PetscInt *lits)
1219 {
1220   PetscFunctionBegin;
1221   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1222   PetscValidIntPointer(lits,2);
1223   *lits = tao->ksp_tot_its;
1224   PetscFunctionReturn(0);
1225 }
1226 
1227 #undef __FUNCT__
1228 #define __FUNCT__ "TaoGetLineSearch"
1229 /*@
1230   TaoGetLineSearch - Gets the line search used by the optimization solver.
1231   Application writers should use TaoGetLineSearch if they need direct access
1232   to the TaoLineSearch object.
1233 
1234   Not Collective
1235 
1236    Input Parameters:
1237 .  tao - the TAO solver
1238 
1239    Output Parameters:
1240 .  ls - the line search used in the optimization solver
1241 
1242    Level: intermediate
1243 
1244 @*/
1245 PetscErrorCode TaoGetLineSearch(Tao tao, TaoLineSearch *ls)
1246 {
1247   PetscFunctionBegin;
1248   *ls = tao->linesearch;
1249   PetscFunctionReturn(0);
1250 }
1251 
1252 #undef __FUNCT__
1253 #define __FUNCT__ "TaoAddLineSearchCounts"
1254 /*@
1255   TaoAddLineSearchCounts - Adds the number of function evaluations spent
1256   in the line search to the running total.
1257 
1258    Input Parameters:
1259 +  tao - the TAO solver
1260 -  ls - the line search used in the optimization solver
1261 
1262    Level: developer
1263 
1264 .seealso: TaoLineSearchApply()
1265 @*/
1266 PetscErrorCode TaoAddLineSearchCounts(Tao tao)
1267 {
1268   PetscErrorCode ierr;
1269   PetscBool      flg;
1270   PetscInt       nfeval,ngeval,nfgeval;
1271 
1272   PetscFunctionBegin;
1273   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1274   if (tao->linesearch) {
1275     ierr = TaoLineSearchIsUsingTaoRoutines(tao->linesearch,&flg);CHKERRQ(ierr);
1276     if (!flg) {
1277       ierr = TaoLineSearchGetNumberFunctionEvaluations(tao->linesearch,&nfeval,&ngeval,&nfgeval);CHKERRQ(ierr);
1278       tao->nfuncs+=nfeval;
1279       tao->ngrads+=ngeval;
1280       tao->nfuncgrads+=nfgeval;
1281     }
1282   }
1283   PetscFunctionReturn(0);
1284 }
1285 
1286 #undef __FUNCT__
1287 #define __FUNCT__ "TaoGetSolutionVector"
1288 /*@
1289   TaoGetSolutionVector - Returns the vector with the current TAO solution
1290 
1291   Not Collective
1292 
1293   Input Parameter:
1294 . tao - the Tao context
1295 
1296   Output Parameter:
1297 . X - the current solution
1298 
1299   Level: intermediate
1300 
1301   Note:  The returned vector will be the same object that was passed into TaoSetInitialVector()
1302 @*/
1303 PetscErrorCode TaoGetSolutionVector(Tao tao, Vec *X)
1304 {
1305   PetscFunctionBegin;
1306   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1307   *X = tao->solution;
1308   PetscFunctionReturn(0);
1309 }
1310 
1311 #undef __FUNCT__
1312 #define __FUNCT__ "TaoGetGradientVector"
1313 /*@
1314   TaoGetGradientVector - Returns the vector with the current TAO gradient
1315 
1316   Not Collective
1317 
1318   Input Parameter:
1319 . tao - the Tao context
1320 
1321   Output Parameter:
1322 . G - the current solution
1323 
1324   Level: intermediate
1325 @*/
1326 PetscErrorCode TaoGetGradientVector(Tao tao, Vec *G)
1327 {
1328   PetscFunctionBegin;
1329   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1330   *G = tao->gradient;
1331   PetscFunctionReturn(0);
1332 }
1333 
1334 #undef __FUNCT__
1335 #define __FUNCT__ "TaoResetStatistics"
1336 /*@
1337    TaoResetStatistics - Initialize the statistics used by TAO for all of the solvers.
1338    These statistics include the iteration number, residual norms, and convergence status.
1339    This routine gets called before solving each optimization problem.
1340 
1341    Collective on Tao
1342 
1343    Input Parameters:
1344 .  solver - the Tao context
1345 
1346    Level: developer
1347 
1348 .seealso: TaoCreate(), TaoSolve()
1349 @*/
1350 PetscErrorCode TaoResetStatistics(Tao tao)
1351 {
1352   PetscFunctionBegin;
1353   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1354   tao->niter        = 0;
1355   tao->nfuncs       = 0;
1356   tao->nfuncgrads   = 0;
1357   tao->ngrads       = 0;
1358   tao->nhess        = 0;
1359   tao->njac         = 0;
1360   tao->nconstraints = 0;
1361   tao->ksp_its      = 0;
1362   tao->ksp_tot_its      = 0;
1363   tao->reason       = TAO_CONTINUE_ITERATING;
1364   tao->residual     = 0.0;
1365   tao->cnorm        = 0.0;
1366   tao->step         = 0.0;
1367   tao->lsflag       = PETSC_FALSE;
1368   if (tao->hist_reset) tao->hist_len=0;
1369   PetscFunctionReturn(0);
1370 }
1371 
1372 #undef __FUNCT__
1373 #define __FUNCT__ "TaoSetConvergenceTest"
1374 /*@C
1375   TaoSetConvergenceTest - Sets the function that is to be used to test
1376   for convergence o fthe iterative minimization solution.  The new convergence
1377   testing routine will replace TAO's default convergence test.
1378 
1379   Logically Collective on Tao
1380 
1381   Input Parameters:
1382 + tao - the Tao object
1383 . conv - the routine to test for convergence
1384 - ctx - [optional] context for private data for the convergence routine
1385         (may be NULL)
1386 
1387   Calling sequence of conv:
1388 $   PetscErrorCode conv(Tao tao, void *ctx)
1389 
1390 + tao - the Tao object
1391 - ctx - [optional] convergence context
1392 
1393   Note: The new convergence testing routine should call TaoSetConvergedReason().
1394 
1395   Level: advanced
1396 
1397 .seealso: TaoSetConvergedReason(), TaoGetSolutionStatus(), TaoGetTolerances(), TaoSetMonitor
1398 
1399 @*/
1400 PetscErrorCode TaoSetConvergenceTest(Tao tao, PetscErrorCode (*conv)(Tao,void*), void *ctx)
1401 {
1402   PetscFunctionBegin;
1403   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1404   (tao)->ops->convergencetest = conv;
1405   (tao)->cnvP = ctx;
1406   PetscFunctionReturn(0);
1407 }
1408 
1409 #undef __FUNCT__
1410 #define __FUNCT__ "TaoSetMonitor"
1411 /*@C
1412    TaoSetMonitor - Sets an ADDITIONAL function that is to be used at every
1413    iteration of the solver to display the iteration's
1414    progress.
1415 
1416    Logically Collective on Tao
1417 
1418    Input Parameters:
1419 +  tao - the Tao solver context
1420 .  mymonitor - monitoring routine
1421 -  mctx - [optional] user-defined context for private data for the
1422           monitor routine (may be NULL)
1423 
1424    Calling sequence of mymonitor:
1425 $     int mymonitor(Tao tao,void *mctx)
1426 
1427 +    tao - the Tao solver context
1428 -    mctx - [optional] monitoring context
1429 
1430 
1431    Options Database Keys:
1432 +    -tao_monitor        - sets TaoDefaultMonitor()
1433 .    -tao_smonitor       - sets short monitor
1434 .    -tao_cmonitor       - same as smonitor plus constraint norm
1435 .    -tao_view_solution   - view solution at each iteration
1436 .    -tao_view_gradient   - view gradient at each iteration
1437 .    -tao_view_separableobjective - view separable objective function at each iteration
1438 -    -tao_cancelmonitors - cancels all monitors that have been hardwired into a code by calls to TaoSetMonitor(), but does not cancel those set via the options database.
1439 
1440 
1441    Notes:
1442    Several different monitoring routines may be set by calling
1443    TaoSetMonitor() multiple times; all will be called in the
1444    order in which they were set.
1445 
1446    Fortran Notes: Only one monitor function may be set
1447 
1448    Level: intermediate
1449 
1450 .seealso: TaoDefaultMonitor(), TaoCancelMonitors(),  TaoSetDestroyRoutine()
1451 @*/
1452 PetscErrorCode TaoSetMonitor(Tao tao, PetscErrorCode (*func)(Tao, void*), void *ctx,PetscErrorCode (*dest)(void**))
1453 {
1454   PetscErrorCode ierr;
1455   PetscInt       i;
1456 
1457   PetscFunctionBegin;
1458   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1459   if (tao->numbermonitors >= MAXTAOMONITORS) SETERRQ1(PETSC_COMM_SELF,1,"Cannot attach another monitor -- max=",MAXTAOMONITORS);
1460 
1461   for (i=0; i<tao->numbermonitors;i++) {
1462     if (func == tao->monitor[i] && dest == tao->monitordestroy[i] && ctx == tao->monitorcontext[i]) {
1463       if (dest) {
1464         ierr = (*dest)(&ctx);CHKERRQ(ierr);
1465       }
1466       PetscFunctionReturn(0);
1467     }
1468   }
1469   tao->monitor[tao->numbermonitors] = func;
1470   tao->monitorcontext[tao->numbermonitors] = ctx;
1471   tao->monitordestroy[tao->numbermonitors] = dest;
1472   ++tao->numbermonitors;
1473   PetscFunctionReturn(0);
1474 }
1475 
1476 #undef __FUNCT__
1477 #define __FUNCT__ "TaoCancelMonitors"
1478 /*@
1479    TaoCancelMonitors - Clears all the monitor functions for a Tao object.
1480 
1481    Logically Collective on Tao
1482 
1483    Input Parameters:
1484 .  tao - the Tao solver context
1485 
1486    Options Database:
1487 .  -tao_cancelmonitors - cancels all monitors that have been hardwired
1488     into a code by calls to TaoSetMonitor(), but does not cancel those
1489     set via the options database
1490 
1491    Notes:
1492    There is no way to clear one specific monitor from a Tao object.
1493 
1494    Level: advanced
1495 
1496 .seealso: TaoDefaultMonitor(), TaoSetMonitor()
1497 @*/
1498 PetscErrorCode TaoCancelMonitors(Tao tao)
1499 {
1500   PetscInt       i;
1501   PetscErrorCode ierr;
1502 
1503   PetscFunctionBegin;
1504   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
1505   for (i=0;i<tao->numbermonitors;i++) {
1506     if (tao->monitordestroy[i]) {
1507       ierr = (*tao->monitordestroy[i])(&tao->monitorcontext[i]);CHKERRQ(ierr);
1508     }
1509   }
1510   tao->numbermonitors=0;
1511   PetscFunctionReturn(0);
1512 }
1513 
1514 #undef __FUNCT__
1515 #define __FUNCT__ "TaoDefaultMonitor"
1516 /*@
1517    TaoDefaultMonitor - Default routine for monitoring progress of the
1518    Tao solvers (default).  This monitor prints the function value and gradient
1519    norm at each iteration.  It can be turned on from the command line using the
1520    -tao_monitor option
1521 
1522    Collective on Tao
1523 
1524    Input Parameters:
1525 +  tao - the Tao context
1526 -  ctx - PetscViewer context or NULL
1527 
1528    Options Database Keys:
1529 .  -tao_monitor
1530 
1531    Level: advanced
1532 
1533 .seealso: TaoDefaultSMonitor(), TaoSetMonitor()
1534 @*/
1535 PetscErrorCode TaoDefaultMonitor(Tao tao, void *ctx)
1536 {
1537   PetscErrorCode ierr;
1538   PetscInt       its;
1539   PetscReal      fct,gnorm;
1540   PetscViewer    viewer = (PetscViewer)ctx;
1541 
1542   PetscFunctionBegin;
1543   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2);
1544   its=tao->niter;
1545   fct=tao->fc;
1546   gnorm=tao->residual;
1547   ierr=PetscViewerASCIIPrintf(viewer,"iter = %3D,",its);CHKERRQ(ierr);
1548   ierr=PetscViewerASCIIPrintf(viewer," Function value: %g,",(double)fct);CHKERRQ(ierr);
1549   if (gnorm >= PETSC_INFINITY) {
1550     ierr=PetscViewerASCIIPrintf(viewer,"  Residual: Inf \n");CHKERRQ(ierr);
1551   } else {
1552     ierr=PetscViewerASCIIPrintf(viewer,"  Residual: %g \n",(double)gnorm);CHKERRQ(ierr);
1553   }
1554   PetscFunctionReturn(0);
1555 }
1556 
1557 #undef __FUNCT__
1558 #define __FUNCT__ "TaoDefaultSMonitor"
1559 /*@
1560    TaoDefaultSMonitor - Default routine for monitoring progress of the
1561    solver. Same as TaoDefaultMonitor() except
1562    it prints fewer digits of the residual as the residual gets smaller.
1563    This is because the later digits are meaningless and are often
1564    different on different machines; by using this routine different
1565    machines will usually generate the same output. It can be turned on
1566    by using the -tao_smonitor option
1567 
1568    Collective on Tao
1569 
1570    Input Parameters:
1571 +  tao - the Tao context
1572 -  ctx - PetscViewer context of type ASCII
1573 
1574    Options Database Keys:
1575 .  -tao_smonitor
1576 
1577    Level: advanced
1578 
1579 .seealso: TaoDefaultMonitor(), TaoSetMonitor()
1580 @*/
1581 PetscErrorCode TaoDefaultSMonitor(Tao tao, void *ctx)
1582 {
1583   PetscErrorCode ierr;
1584   PetscInt       its;
1585   PetscReal      fct,gnorm;
1586   PetscViewer    viewer = (PetscViewer)ctx;
1587 
1588   PetscFunctionBegin;
1589   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2);
1590   its=tao->niter;
1591   fct=tao->fc;
1592   gnorm=tao->residual;
1593   ierr=PetscViewerASCIIPrintf(viewer,"iter = %3D,",its);CHKERRQ(ierr);
1594   ierr=PetscViewerASCIIPrintf(viewer," Function value %g,",(double)fct);CHKERRQ(ierr);
1595   if (gnorm >= PETSC_INFINITY/2) {
1596     ierr=PetscViewerASCIIPrintf(viewer," Residual: Inf \n");CHKERRQ(ierr);
1597   } else if (gnorm > 1.e-6) {
1598     ierr=PetscViewerASCIIPrintf(viewer," Residual: %g \n",(double)gnorm);CHKERRQ(ierr);
1599   } else if (gnorm > 1.e-11) {
1600     ierr=PetscViewerASCIIPrintf(viewer," Residual: < 1.0e-6 \n");CHKERRQ(ierr);
1601   } else {
1602     ierr=PetscViewerASCIIPrintf(viewer," Residual: < 1.0e-11 \n");CHKERRQ(ierr);
1603   }
1604   PetscFunctionReturn(0);
1605 }
1606 
1607 #undef __FUNCT__
1608 #define __FUNCT__ "TaoDefaultCMonitor"
1609 /*@
1610    TaoDefaultCMonitor - same as TaoDefaultMonitor() except
1611    it prints the norm of the constraints function. It can be turned on
1612    from the command line using the -tao_cmonitor option
1613 
1614    Collective on Tao
1615 
1616    Input Parameters:
1617 +  tao - the Tao context
1618 -  ctx - PetscViewer context or NULL
1619 
1620    Options Database Keys:
1621 .  -tao_cmonitor
1622 
1623    Level: advanced
1624 
1625 .seealso: TaoDefaultMonitor(), TaoSetMonitor()
1626 @*/
1627 PetscErrorCode TaoDefaultCMonitor(Tao tao, void *ctx)
1628 {
1629   PetscErrorCode ierr;
1630   PetscInt       its;
1631   PetscReal      fct,gnorm;
1632   PetscViewer    viewer;
1633 
1634   PetscFunctionBegin;
1635   if (ctx) {
1636     viewer = (PetscViewer)ctx;
1637   } else {
1638     viewer = PETSC_VIEWER_STDOUT_(((PetscObject)tao)->comm);
1639   }
1640   its=tao->niter;
1641   fct=tao->fc;
1642   gnorm=tao->residual;
1643   ierr=PetscViewerASCIIPrintf(viewer,"iter = %D,",its);CHKERRQ(ierr);
1644   ierr=PetscViewerASCIIPrintf(viewer," Function value: %g,",(double)fct);CHKERRQ(ierr);
1645   ierr=PetscViewerASCIIPrintf(viewer,"  Residual: %g ",(double)gnorm);CHKERRQ(ierr);
1646   ierr = PetscViewerASCIIPrintf(viewer,"  Constraint: %g \n",(double)tao->cnorm);CHKERRQ(ierr);
1647   PetscFunctionReturn(0);
1648 }
1649 
1650 #undef __FUNCT__
1651 #define __FUNCT__ "TaoSolutionMonitor"
1652 /*@C
1653    TaoSolutionMonitor - Views the solution at each iteration
1654    It can be turned on from the command line using the
1655    -tao_view_solution option
1656 
1657    Collective on Tao
1658 
1659    Input Parameters:
1660 +  tao - the Tao context
1661 -  ctx - PetscViewer context or NULL
1662 
1663    Options Database Keys:
1664 .  -tao_view_solution
1665 
1666    Level: advanced
1667 
1668 .seealso: TaoDefaultSMonitor(), TaoSetMonitor()
1669 @*/
1670 PetscErrorCode TaoSolutionMonitor(Tao tao, void *ctx)
1671 {
1672   PetscErrorCode ierr;
1673   PetscViewer viewer;
1674 
1675   PetscFunctionBegin;
1676   if (ctx) {
1677     viewer = (PetscViewer)ctx;
1678   } else {
1679     viewer = PETSC_VIEWER_STDOUT_(((PetscObject)tao)->comm);
1680   }
1681   ierr = VecView(tao->solution, viewer);CHKERRQ(ierr);
1682   PetscFunctionReturn(0);
1683 }
1684 
1685 #undef __FUNCT__
1686 #define __FUNCT__ "TaoGradientMonitor"
1687 /*@C
1688    TaoGradientMonitor - Views the gradient at each iteration
1689    It can be turned on from the command line using the
1690    -tao_view_gradient option
1691 
1692    Collective on Tao
1693 
1694    Input Parameters:
1695 +  tao - the Tao context
1696 -  ctx - PetscViewer context or NULL
1697 
1698    Options Database Keys:
1699 .  -tao_view_gradient
1700 
1701    Level: advanced
1702 
1703 .seealso: TaoDefaultSMonitor(), TaoSetMonitor()
1704 @*/
1705 PetscErrorCode TaoGradientMonitor(Tao tao, void *ctx)
1706 {
1707   PetscErrorCode ierr;
1708   PetscViewer viewer;
1709 
1710   PetscFunctionBegin;
1711   if (ctx) {
1712     viewer = (PetscViewer)ctx;
1713   } else {
1714     viewer = PETSC_VIEWER_STDOUT_(((PetscObject)tao)->comm);
1715   }
1716   ierr = VecView(tao->gradient, viewer);CHKERRQ(ierr);
1717   PetscFunctionReturn(0);
1718 }
1719 
1720 #undef __FUNCT__
1721 #define __FUNCT__ "TaoStepDirectionMonitor"
1722 /*@C
1723    TaoStepDirectionMonitor - Views the gradient at each iteration
1724    It can be turned on from the command line using the
1725    -tao_view_gradient option
1726 
1727    Collective on Tao
1728 
1729    Input Parameters:
1730 +  tao - the Tao context
1731 -  ctx - PetscViewer context or NULL
1732 
1733    Options Database Keys:
1734 .  -tao_view_gradient
1735 
1736    Level: advanced
1737 
1738 .seealso: TaoDefaultSMonitor(), TaoSetMonitor()
1739 @*/
1740 PetscErrorCode TaoStepDirectionMonitor(Tao tao, void *ctx)
1741 {
1742   PetscErrorCode ierr;
1743   PetscViewer viewer;
1744   PetscFunctionBegin;
1745   if (ctx) {
1746     viewer = (PetscViewer)ctx;
1747   } else {
1748     viewer = PETSC_VIEWER_STDOUT_(((PetscObject)tao)->comm);
1749   }
1750   ierr = VecView(tao->stepdirection, viewer);CHKERRQ(ierr);
1751   PetscFunctionReturn(0);
1752 }
1753 
1754 #undef __FUNCT__
1755 #define __FUNCT__ "TaoDrawSolutionMonitor"
1756 /*@C
1757    TaoDrawSolutionMonitor - Plots the solution at each iteration
1758    It can be turned on from the command line using the
1759    -tao_draw_solution option
1760 
1761    Collective on Tao
1762 
1763    Input Parameters:
1764 +  tao - the Tao context
1765 -  ctx - PetscViewer context
1766 
1767    Options Database Keys:
1768 .  -tao_draw_solution
1769 
1770    Level: advanced
1771 
1772 .seealso: TaoSolutionMonitor(), TaoSetMonitor(), TaoDrawGradientMonitor
1773 @*/
1774 PetscErrorCode TaoDrawSolutionMonitor(Tao tao, void *ctx)
1775 {
1776   PetscErrorCode ierr;
1777   PetscViewer    viewer = (PetscViewer) ctx;
1778 
1779   PetscFunctionBegin;
1780   ierr = VecView(tao->solution, viewer);CHKERRQ(ierr);
1781   PetscFunctionReturn(0);
1782 }
1783 
1784 #undef __FUNCT__
1785 #define __FUNCT__ "TaoDrawGradientMonitor"
1786 /*@C
1787    TaoDrawGradientMonitor - Plots the gradient at each iteration
1788    It can be turned on from the command line using the
1789    -tao_draw_gradient option
1790 
1791    Collective on Tao
1792 
1793    Input Parameters:
1794 +  tao - the Tao context
1795 -  ctx - PetscViewer context
1796 
1797    Options Database Keys:
1798 .  -tao_draw_gradient
1799 
1800    Level: advanced
1801 
1802 .seealso: TaoGradientMonitor(), TaoSetMonitor(), TaoDrawSolutionMonitor
1803 @*/
1804 PetscErrorCode TaoDrawGradientMonitor(Tao tao, void *ctx)
1805 {
1806   PetscErrorCode ierr;
1807   PetscViewer    viewer = (PetscViewer)ctx;
1808 
1809   PetscFunctionBegin;
1810   ierr = VecView(tao->gradient, viewer);CHKERRQ(ierr);
1811   PetscFunctionReturn(0);
1812 }
1813 
1814 #undef __FUNCT__
1815 #define __FUNCT__ "TaoDrawStepMonitor"
1816 /*@C
1817    TaoDrawStepMonitor - Plots the step direction at each iteration
1818    It can be turned on from the command line using the
1819    -tao_draw_step option
1820 
1821    Collective on Tao
1822 
1823    Input Parameters:
1824 +  tao - the Tao context
1825 -  ctx - PetscViewer context
1826 
1827    Options Database Keys:
1828 .  -tao_draw_step
1829 
1830    Level: advanced
1831 
1832 .seealso: TaoSetMonitor(), TaoDrawSolutionMonitor
1833 @*/
1834 PetscErrorCode TaoDrawStepMonitor(Tao tao, void *ctx)
1835 {
1836   PetscErrorCode ierr;
1837   PetscViewer    viewer = (PetscViewer)(ctx);
1838 
1839   PetscFunctionBegin;
1840   ierr = VecView(tao->stepdirection, viewer);CHKERRQ(ierr);
1841   PetscFunctionReturn(0);
1842 }
1843 
1844 #undef __FUNCT__
1845 #define __FUNCT__ "TaoSeparableObjectiveMonitor"
1846 /*@C
1847    TaoSeparableObjectiveMonitor - Views the separable objective function at each iteration
1848    It can be turned on from the command line using the
1849    -tao_view_separableobjective option
1850 
1851    Collective on Tao
1852 
1853    Input Parameters:
1854 +  tao - the Tao context
1855 -  ctx - PetscViewer context or NULL
1856 
1857    Options Database Keys:
1858 .  -tao_view_separableobjective
1859 
1860    Level: advanced
1861 
1862 .seealso: TaoDefaultSMonitor(), TaoSetMonitor()
1863 @*/
1864 PetscErrorCode TaoSeparableObjectiveMonitor(Tao tao, void *ctx)
1865 {
1866   PetscErrorCode ierr;
1867   PetscViewer    viewer;
1868 
1869   PetscFunctionBegin;
1870   if (ctx) {
1871     viewer = (PetscViewer)ctx;
1872   } else {
1873     viewer = PETSC_VIEWER_STDOUT_(((PetscObject)tao)->comm);
1874   }
1875   ierr = VecView(tao->sep_objective,viewer);CHKERRQ(ierr);
1876   PetscFunctionReturn(0);
1877 }
1878 
1879 #undef __FUNCT__
1880 #define __FUNCT__ "TaoDefaultConvergenceTest"
1881 /*@
1882    TaoDefaultConvergenceTest - Determines whether the solver should continue iterating
1883    or terminate.
1884 
1885    Collective on Tao
1886 
1887    Input Parameters:
1888 +  tao - the Tao context
1889 -  dummy - unused dummy context
1890 
1891    Output Parameter:
1892 .  reason - for terminating
1893 
1894    Notes:
1895    This routine checks the residual in the optimality conditions, the
1896    relative residual in the optimity conditions, the number of function
1897    evaluations, and the function value to test convergence.  Some
1898    solvers may use different convergence routines.
1899 
1900    Level: developer
1901 
1902 .seealso: TaoSetTolerances(),TaoGetConvergedReason(),TaoSetConvergedReason()
1903 @*/
1904 
1905 PetscErrorCode TaoDefaultConvergenceTest(Tao tao,void *dummy)
1906 {
1907   PetscInt           niter=tao->niter, nfuncs=PetscMax(tao->nfuncs,tao->nfuncgrads);
1908   PetscInt           max_funcs=tao->max_funcs;
1909   PetscReal          gnorm=tao->residual, gnorm0=tao->gnorm0;
1910   PetscReal          f=tao->fc, steptol=tao->steptol,trradius=tao->step;
1911   PetscReal          gatol=tao->gatol,grtol=tao->grtol,gttol=tao->gttol;
1912   PetscReal          fatol=tao->fatol,frtol=tao->frtol,catol=tao->catol,crtol=tao->crtol;
1913   PetscReal          fmin=tao->fmin, cnorm=tao->cnorm, cnorm0=tao->cnorm0;
1914   PetscReal          gnorm2;
1915   TaoConvergedReason reason=tao->reason;
1916   PetscErrorCode     ierr;
1917 
1918   PetscFunctionBegin;
1919   PetscValidHeaderSpecific(tao, TAO_CLASSID,1);
1920   if (reason != TAO_CONTINUE_ITERATING) {
1921     PetscFunctionReturn(0);
1922   }
1923   gnorm2=gnorm*gnorm;
1924 
1925   if (PetscIsInfOrNanReal(f)) {
1926     ierr = PetscInfo(tao,"Failed to converged, function value is Inf or NaN\n");CHKERRQ(ierr);
1927     reason = TAO_DIVERGED_NAN;
1928   } else if (f <= fmin && cnorm <=catol) {
1929     ierr = PetscInfo2(tao,"Converged due to function value %g < minimum function value %g\n", (double)f,(double)fmin);CHKERRQ(ierr);
1930     reason = TAO_CONVERGED_MINF;
1931   } else if (gnorm2 <= fatol && cnorm <=catol) {
1932     ierr = PetscInfo2(tao,"Converged due to estimated f(X) - f(X*) = %g < %g\n",(double)gnorm2,(double)fatol);CHKERRQ(ierr);
1933     reason = TAO_CONVERGED_FATOL;
1934   } else if (f != 0 && gnorm2 / PetscAbsReal(f)<= frtol && cnorm/PetscMax(cnorm0,1.0) <= crtol) {
1935     ierr = PetscInfo2(tao,"Converged due to estimated |f(X)-f(X*)|/f(X) = %g < %g\n",(double)(gnorm2/PetscAbsReal(f)),(double)frtol);CHKERRQ(ierr);
1936     reason = TAO_CONVERGED_FRTOL;
1937   } else if (gnorm<= gatol && cnorm <=catol) {
1938     ierr = PetscInfo2(tao,"Converged due to residual norm ||g(X)||=%g < %g\n",(double)gnorm,(double)gatol);CHKERRQ(ierr);
1939     reason = TAO_CONVERGED_GATOL;
1940   } else if ( f!=0 && PetscAbsReal(gnorm/f) <= grtol && cnorm <= crtol) {
1941     ierr = PetscInfo2(tao,"Converged due to residual ||g(X)||/|f(X)| =%g < %g\n",(double)(gnorm/f),(double)grtol);CHKERRQ(ierr);
1942     reason = TAO_CONVERGED_GRTOL;
1943   } else if (gnorm0 != 0 && gnorm/gnorm0 <= gttol && cnorm <= crtol) {
1944     ierr = PetscInfo2(tao,"Converged due to relative residual norm ||g(X)||/||g(X0)|| = %g < %g\n",(double)(gnorm/gnorm0),(double)gttol);CHKERRQ(ierr);
1945     reason = TAO_CONVERGED_GTTOL;
1946   } else if (nfuncs > max_funcs){
1947     ierr = PetscInfo2(tao,"Exceeded maximum number of function evaluations: %D > %D\n", nfuncs,max_funcs);CHKERRQ(ierr);
1948     reason = TAO_DIVERGED_MAXFCN;
1949   } else if ( tao->lsflag != 0 ){
1950     ierr = PetscInfo(tao,"Tao Line Search failure.\n");CHKERRQ(ierr);
1951     reason = TAO_DIVERGED_LS_FAILURE;
1952   } else if (trradius < steptol && niter > 0){
1953     ierr = PetscInfo2(tao,"Trust region/step size too small: %g < %g\n", (double)trradius,(double)steptol);CHKERRQ(ierr);
1954     reason = TAO_CONVERGED_STEPTOL;
1955   } else if (niter > tao->max_it) {
1956     ierr = PetscInfo2(tao,"Exceeded maximum number of iterations: %D > %D\n",niter,tao->max_it);CHKERRQ(ierr);
1957     reason = TAO_DIVERGED_MAXITS;
1958   } else {
1959     reason = TAO_CONTINUE_ITERATING;
1960   }
1961   tao->reason = reason;
1962   PetscFunctionReturn(0);
1963 }
1964 
1965 #undef __FUNCT__
1966 #define __FUNCT__ "TaoSetOptionsPrefix"
1967 /*@C
1968    TaoSetOptionsPrefix - Sets the prefix used for searching for all
1969    TAO options in the database.
1970 
1971 
1972    Logically Collective on Tao
1973 
1974    Input Parameters:
1975 +  tao - the Tao context
1976 -  prefix - the prefix string to prepend to all TAO option requests
1977 
1978    Notes:
1979    A hyphen (-) must NOT be given at the beginning of the prefix name.
1980    The first character of all runtime options is AUTOMATICALLY the hyphen.
1981 
1982    For example, to distinguish between the runtime options for two
1983    different TAO solvers, one could call
1984 .vb
1985       TaoSetOptionsPrefix(tao1,"sys1_")
1986       TaoSetOptionsPrefix(tao2,"sys2_")
1987 .ve
1988 
1989    This would enable use of different options for each system, such as
1990 .vb
1991       -sys1_tao_method blmvm -sys1_tao_gtol 1.e-3
1992       -sys2_tao_method lmvm  -sys2_tao_gtol 1.e-4
1993 .ve
1994 
1995 
1996    Level: advanced
1997 
1998 .seealso: TaoAppendOptionsPrefix(), TaoGetOptionsPrefix()
1999 @*/
2000 
2001 PetscErrorCode TaoSetOptionsPrefix(Tao tao, const char p[])
2002 {
2003   PetscErrorCode ierr;
2004 
2005   PetscFunctionBegin;
2006   ierr = PetscObjectSetOptionsPrefix((PetscObject)tao,p);CHKERRQ(ierr);
2007   if (tao->linesearch) {
2008     ierr = TaoLineSearchSetOptionsPrefix(tao->linesearch,p);CHKERRQ(ierr);
2009   }
2010   if (tao->ksp) {
2011     ierr = KSPSetOptionsPrefix(tao->ksp,p);CHKERRQ(ierr);
2012   }
2013   PetscFunctionReturn(0);
2014 }
2015 
2016 #undef __FUNCT__
2017 #define __FUNCT__ "TaoAppendOptionsPrefix"
2018 /*@C
2019    TaoAppendOptionsPrefix - Appends to the prefix used for searching for all
2020    TAO options in the database.
2021 
2022 
2023    Logically Collective on Tao
2024 
2025    Input Parameters:
2026 +  tao - the Tao solver context
2027 -  prefix - the prefix string to prepend to all TAO option requests
2028 
2029    Notes:
2030    A hyphen (-) must NOT be given at the beginning of the prefix name.
2031    The first character of all runtime options is AUTOMATICALLY the hyphen.
2032 
2033 
2034    Level: advanced
2035 
2036 .seealso: TaoSetOptionsPrefix(), TaoGetOptionsPrefix()
2037 @*/
2038 PetscErrorCode TaoAppendOptionsPrefix(Tao tao, const char p[])
2039 {
2040   PetscErrorCode ierr;
2041 
2042   PetscFunctionBegin;
2043   ierr = PetscObjectAppendOptionsPrefix((PetscObject)tao,p);CHKERRQ(ierr);
2044   if (tao->linesearch) {
2045     ierr = TaoLineSearchSetOptionsPrefix(tao->linesearch,p);CHKERRQ(ierr);
2046   }
2047   if (tao->ksp) {
2048     ierr = KSPSetOptionsPrefix(tao->ksp,p);CHKERRQ(ierr);
2049   }
2050   PetscFunctionReturn(0);
2051 }
2052 
2053 #undef __FUNCT__
2054 #define __FUNCT__ "TaoGetOptionsPrefix"
2055 /*@C
2056   TaoGetOptionsPrefix - Gets the prefix used for searching for all
2057   TAO options in the database
2058 
2059   Not Collective
2060 
2061   Input Parameters:
2062 . tao - the Tao context
2063 
2064   Output Parameters:
2065 . prefix - pointer to the prefix string used is returned
2066 
2067   Notes: On the fortran side, the user should pass in a string 'prefix' of
2068   sufficient length to hold the prefix.
2069 
2070   Level: advanced
2071 
2072 .seealso: TaoSetOptionsPrefix(), TaoAppendOptionsPrefix()
2073 @*/
2074 PetscErrorCode TaoGetOptionsPrefix(Tao tao, const char *p[])
2075 {
2076    return PetscObjectGetOptionsPrefix((PetscObject)tao,p);
2077 }
2078 
2079 #undef __FUNCT__
2080 #define __FUNCT__ "TaoSetType"
2081 /*@C
2082    TaoSetType - Sets the method for the unconstrained minimization solver.
2083 
2084    Collective on Tao
2085 
2086    Input Parameters:
2087 +  solver - the Tao solver context
2088 -  type - a known method
2089 
2090    Options Database Key:
2091 .  -tao_type <type> - Sets the method; use -help for a list
2092    of available methods (for instance, "-tao_type lmvm" or "-tao_type tron")
2093 
2094    Available methods include:
2095 +    nls - Newton's method with line search for unconstrained minimization
2096 .    ntr - Newton's method with trust region for unconstrained minimization
2097 .    ntl - Newton's method with trust region, line search for unconstrained minimization
2098 .    lmvm - Limited memory variable metric method for unconstrained minimization
2099 .    cg - Nonlinear conjugate gradient method for unconstrained minimization
2100 .    nm - Nelder-Mead algorithm for derivate-free unconstrained minimization
2101 .    tron - Newton Trust Region method for bound constrained minimization
2102 .    gpcg - Newton Trust Region method for quadratic bound constrained minimization
2103 .    blmvm - Limited memory variable metric method for bound constrained minimization
2104 -    pounders - Model-based algorithm pounder extended for nonlinear least squares
2105 
2106   Level: intermediate
2107 
2108 .seealso: TaoCreate(), TaoGetType(), TaoType
2109 
2110 @*/
2111 PetscErrorCode TaoSetType(Tao tao, const TaoType type)
2112 {
2113   PetscErrorCode ierr;
2114   PetscErrorCode (*create_xxx)(Tao);
2115   PetscBool      issame;
2116 
2117   PetscFunctionBegin;
2118   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2119 
2120   ierr = PetscObjectTypeCompare((PetscObject)tao,type,&issame);CHKERRQ(ierr);
2121   if (issame) PetscFunctionReturn(0);
2122 
2123   ierr = PetscFunctionListFind(TaoList, type, (void(**)(void))&create_xxx);CHKERRQ(ierr);
2124   if (!create_xxx) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_UNKNOWN_TYPE,"Unable to find requested Tao type %s",type);
2125 
2126   /* Destroy the existing solver information */
2127   if (tao->ops->destroy) {
2128     ierr = (*tao->ops->destroy)(tao);CHKERRQ(ierr);
2129   }
2130   ierr = KSPDestroy(&tao->ksp);CHKERRQ(ierr);
2131   ierr = TaoLineSearchDestroy(&tao->linesearch);CHKERRQ(ierr);
2132   ierr = VecDestroy(&tao->gradient);CHKERRQ(ierr);
2133   ierr = VecDestroy(&tao->stepdirection);CHKERRQ(ierr);
2134 
2135   tao->ops->setup = 0;
2136   tao->ops->solve = 0;
2137   tao->ops->view  = 0;
2138   tao->ops->setfromoptions = 0;
2139   tao->ops->destroy = 0;
2140 
2141   tao->setupcalled = PETSC_FALSE;
2142 
2143   ierr = (*create_xxx)(tao);CHKERRQ(ierr);
2144   ierr = PetscObjectChangeTypeName((PetscObject)tao,type);CHKERRQ(ierr);
2145   PetscFunctionReturn(0);
2146 }
2147 
2148 #undef __FUNCT__
2149 #define __FUNCT__ "TaoRegister"
2150 /*MC
2151    TaoRegister - Adds a method to the TAO package for unconstrained minimization.
2152 
2153    Synopsis:
2154    TaoRegister(char *name_solver,char *path,char *name_Create,int (*routine_Create)(Tao))
2155 
2156    Not collective
2157 
2158    Input Parameters:
2159 +  sname - name of a new user-defined solver
2160 -  func - routine to Create method context
2161 
2162    Notes:
2163    TaoRegister() may be called multiple times to add several user-defined solvers.
2164 
2165    Sample usage:
2166 .vb
2167    TaoRegister("my_solver",MySolverCreate);
2168 .ve
2169 
2170    Then, your solver can be chosen with the procedural interface via
2171 $     TaoSetType(tao,"my_solver")
2172    or at runtime via the option
2173 $     -tao_type my_solver
2174 
2175    Level: advanced
2176 
2177 .seealso: TaoRegisterAll(), TaoRegisterDestroy()
2178 M*/
2179 PetscErrorCode TaoRegister(const char sname[], PetscErrorCode (*func)(Tao))
2180 {
2181   PetscErrorCode ierr;
2182 
2183   PetscFunctionBegin;
2184   ierr = PetscFunctionListAdd(&TaoList,sname, (void (*)(void))func);CHKERRQ(ierr);
2185   PetscFunctionReturn(0);
2186 }
2187 
2188 #undef __FUNCT__
2189 #define __FUNCT__ "TaoRegisterDestroy"
2190 /*@C
2191    TaoRegisterDestroy - Frees the list of minimization solvers that were
2192    registered by TaoRegisterDynamic().
2193 
2194    Not Collective
2195 
2196    Level: advanced
2197 
2198 .seealso: TaoRegisterAll(), TaoRegister()
2199 @*/
2200 PetscErrorCode TaoRegisterDestroy(void)
2201 {
2202   PetscErrorCode ierr;
2203   PetscFunctionBegin;
2204   ierr = PetscFunctionListDestroy(&TaoList);CHKERRQ(ierr);
2205   TaoRegisterAllCalled = PETSC_FALSE;
2206   PetscFunctionReturn(0);
2207 }
2208 
2209 #undef __FUNCT__
2210 #define __FUNCT__ "TaoGetIterationNumber"
2211 /*@
2212    TaoGetIterationNumber - Gets the number of Tao iterations completed
2213    at this time.
2214 
2215    Not Collective
2216 
2217    Input Parameter:
2218 .  tao - Tao context
2219 
2220    Output Parameter:
2221 .  iter - iteration number
2222 
2223    Notes:
2224    For example, during the computation of iteration 2 this would return 1.
2225 
2226 
2227    Level: intermediate
2228 
2229 .keywords: Tao, nonlinear, get, iteration, number,
2230 
2231 .seealso:   TaoGetLinearSolveIterations()
2232 @*/
2233 PetscErrorCode  TaoGetIterationNumber(Tao tao,PetscInt *iter)
2234 {
2235   PetscFunctionBegin;
2236   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2237   PetscValidIntPointer(iter,2);
2238   *iter = tao->niter;
2239   PetscFunctionReturn(0);
2240 }
2241 
2242 #undef __FUNCT__
2243 #define __FUNCT__ "TaoSetIterationNumber"
2244 /*@
2245    TaoSetIterationNumber - Sets the current iteration number.
2246 
2247    Not Collective
2248 
2249    Input Parameter:
2250 .  tao - Tao context
2251 .  iter - iteration number
2252 
2253    Level: developer
2254 
2255 .keywords: Tao, nonlinear, set, iteration, number,
2256 
2257 .seealso:   TaoGetLinearSolveIterations()
2258 @*/
2259 PetscErrorCode  TaoSetIterationNumber(Tao tao,PetscInt iter)
2260 {
2261   PetscErrorCode ierr;
2262 
2263   PetscFunctionBegin;
2264   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2265   ierr       = PetscObjectSAWsTakeAccess((PetscObject)tao);CHKERRQ(ierr);
2266   tao->niter = iter;
2267   ierr       = PetscObjectSAWsGrantAccess((PetscObject)tao);CHKERRQ(ierr);
2268   PetscFunctionReturn(0);
2269 }
2270 
2271 #undef __FUNCT__
2272 #define __FUNCT__ "TaoGetTotalIterationNumber"
2273 /*@
2274    TaoGetTotalIterationNumber - Gets the total number of Tao iterations
2275    completed. This number keeps accumulating if multiple solves
2276    are called with the Tao object.
2277 
2278    Not Collective
2279 
2280    Input Parameter:
2281 .  tao - Tao context
2282 
2283    Output Parameter:
2284 .  iter - iteration number
2285 
2286    Notes:
2287    The total iteration count is updated after each solve, if there is a current
2288    TaoSolve() in progress then those iterations are not yet counted.
2289 
2290    Level: intermediate
2291 
2292 .keywords: Tao, nonlinear, get, iteration, number,
2293 
2294 .seealso:   TaoGetLinearSolveIterations()
2295 @*/
2296 PetscErrorCode  TaoGetTotalIterationNumber(Tao tao,PetscInt *iter)
2297 {
2298   PetscFunctionBegin;
2299   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2300   PetscValidIntPointer(iter,2);
2301   *iter = tao->ntotalits;
2302   PetscFunctionReturn(0);
2303 }
2304 
2305 #undef __FUNCT__
2306 #define __FUNCT__ "TaoSetTotalIterationNumber"
2307 /*@
2308    TaoSetTotalIterationNumber - Sets the current total iteration number.
2309 
2310    Not Collective
2311 
2312    Input Parameter:
2313 .  tao - Tao context
2314 .  iter - iteration number
2315 
2316    Level: developer
2317 
2318 .keywords: Tao, nonlinear, set, iteration, number,
2319 
2320 .seealso:   TaoGetLinearSolveIterations()
2321 @*/
2322 PetscErrorCode  TaoSetTotalIterationNumber(Tao tao,PetscInt iter)
2323 {
2324   PetscErrorCode ierr;
2325 
2326   PetscFunctionBegin;
2327   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2328   ierr       = PetscObjectSAWsTakeAccess((PetscObject)tao);CHKERRQ(ierr);
2329   tao->ntotalits = iter;
2330   ierr       = PetscObjectSAWsGrantAccess((PetscObject)tao);CHKERRQ(ierr);
2331   PetscFunctionReturn(0);
2332 }
2333 
2334 #undef __FUNCT__
2335 #define __FUNCT__ "TaoSetConvergedReason"
2336 /*@
2337   TaoSetConvergedReason - Sets the termination flag on a Tao object
2338 
2339   Logically Collective on Tao
2340 
2341   Input Parameters:
2342 + tao - the Tao context
2343 - reason - one of
2344 $     TAO_CONVERGED_ATOL (2),
2345 $     TAO_CONVERGED_RTOL (3),
2346 $     TAO_CONVERGED_STEPTOL (4),
2347 $     TAO_CONVERGED_MINF (5),
2348 $     TAO_CONVERGED_USER (6),
2349 $     TAO_DIVERGED_MAXITS (-2),
2350 $     TAO_DIVERGED_NAN (-4),
2351 $     TAO_DIVERGED_MAXFCN (-5),
2352 $     TAO_DIVERGED_LS_FAILURE (-6),
2353 $     TAO_DIVERGED_TR_REDUCTION (-7),
2354 $     TAO_DIVERGED_USER (-8),
2355 $     TAO_CONTINUE_ITERATING (0)
2356 
2357    Level: intermediate
2358 
2359 @*/
2360 PetscErrorCode TaoSetConvergedReason(Tao tao, TaoConvergedReason reason)
2361 {
2362   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2363   PetscFunctionBegin;
2364   tao->reason = reason;
2365   PetscFunctionReturn(0);
2366 }
2367 
2368 #undef __FUNCT__
2369 #define __FUNCT__ "TaoGetConvergedReason"
2370 /*@
2371    TaoGetConvergedReason - Gets the reason the Tao iteration was stopped.
2372 
2373    Not Collective
2374 
2375    Input Parameter:
2376 .  tao - the Tao solver context
2377 
2378    Output Parameter:
2379 .  reason - one of
2380 $  TAO_CONVERGED_FATOL (1)           f(X)-f(X*) <= fatol
2381 $  TAO_CONVERGED_FRTOL (2)           |f(X) - f(X*)|/|f(X)| < frtol
2382 $  TAO_CONVERGED_GATOL (3)           ||g(X)|| < gatol
2383 $  TAO_CONVERGED_GRTOL (4)           ||g(X)|| / f(X)  < grtol
2384 $  TAO_CONVERGED_GTTOL (5)           ||g(X)|| / ||g(X0)|| < gttol
2385 $  TAO_CONVERGED_STEPTOL (6)         step size small
2386 $  TAO_CONVERGED_MINF (7)            F < F_min
2387 $  TAO_CONVERGED_USER (8)            User defined
2388 $  TAO_DIVERGED_MAXITS (-2)          its > maxits
2389 $  TAO_DIVERGED_NAN (-4)             Numerical problems
2390 $  TAO_DIVERGED_MAXFCN (-5)          fevals > max_funcsals
2391 $  TAO_DIVERGED_LS_FAILURE (-6)      line search failure
2392 $  TAO_DIVERGED_TR_REDUCTION (-7)    trust region failure
2393 $  TAO_DIVERGED_USER(-8)             (user defined)
2394  $  TAO_CONTINUE_ITERATING (0)
2395 
2396    where
2397 +  X - current solution
2398 .  X0 - initial guess
2399 .  f(X) - current function value
2400 .  f(X*) - true solution (estimated)
2401 .  g(X) - current gradient
2402 .  its - current iterate number
2403 .  maxits - maximum number of iterates
2404 .  fevals - number of function evaluations
2405 -  max_funcsals - maximum number of function evaluations
2406 
2407    Level: intermediate
2408 
2409 .seealso: TaoSetConvergenceTest(), TaoSetTolerances()
2410 
2411 @*/
2412 PetscErrorCode TaoGetConvergedReason(Tao tao, TaoConvergedReason *reason)
2413 {
2414   PetscFunctionBegin;
2415   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2416   PetscValidPointer(reason,2);
2417   *reason = tao->reason;
2418   PetscFunctionReturn(0);
2419 }
2420 
2421 #undef __FUNCT__
2422 #define __FUNCT__ "TaoGetSolutionStatus"
2423 /*@
2424   TaoGetSolutionStatus - Get the current iterate, objective value,
2425   residual, infeasibility, and termination
2426 
2427   Not Collective
2428 
2429    Input Parameters:
2430 .  tao - the Tao context
2431 
2432    Output Parameters:
2433 +  iterate - the current iterate number (>=0)
2434 .  f - the current function value
2435 .  gnorm - the square of the gradient norm, duality gap, or other measure indicating distance from optimality.
2436 .  cnorm - the infeasibility of the current solution with regard to the constraints.
2437 .  xdiff - the step length or trust region radius of the most recent iterate.
2438 -  reason - The termination reason, which can equal TAO_CONTINUE_ITERATING
2439 
2440    Level: intermediate
2441 
2442    Note:
2443    TAO returns the values set by the solvers in the routine TaoMonitor().
2444 
2445    Note:
2446    If any of the output arguments are set to NULL, no corresponding value will be returned.
2447 
2448 .seealso: TaoMonitor(), TaoGetConvergedReason()
2449 @*/
2450 PetscErrorCode TaoGetSolutionStatus(Tao tao, PetscInt *its, PetscReal *f, PetscReal *gnorm, PetscReal *cnorm, PetscReal *xdiff, TaoConvergedReason *reason)
2451 {
2452   PetscFunctionBegin;
2453   if (its) *its=tao->niter;
2454   if (f) *f=tao->fc;
2455   if (gnorm) *gnorm=tao->residual;
2456   if (cnorm) *cnorm=tao->cnorm;
2457   if (reason) *reason=tao->reason;
2458   if (xdiff) *xdiff=tao->step;
2459   PetscFunctionReturn(0);
2460 }
2461 
2462 #undef __FUNCT__
2463 #define __FUNCT__ "TaoGetType"
2464 /*@C
2465    TaoGetType - Gets the current Tao algorithm.
2466 
2467    Not Collective
2468 
2469    Input Parameter:
2470 .  tao - the Tao solver context
2471 
2472    Output Parameter:
2473 .  type - Tao method
2474 
2475    Level: intermediate
2476 
2477 @*/
2478 PetscErrorCode TaoGetType(Tao tao, const TaoType *type)
2479 {
2480   PetscFunctionBegin;
2481   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2482   PetscValidPointer(type,2);
2483   *type=((PetscObject)tao)->type_name;
2484   PetscFunctionReturn(0);
2485 }
2486 
2487 #undef __FUNCT__
2488 #define __FUNCT__ "TaoMonitor"
2489 /*@C
2490   TaoMonitor - Monitor the solver and the current solution.  This
2491   routine will record the iteration number and residual statistics,
2492   call any monitors specified by the user, and calls the convergence-check routine.
2493 
2494    Input Parameters:
2495 +  tao - the Tao context
2496 .  its - the current iterate number (>=0)
2497 .  f - the current objective function value
2498 .  res - the gradient norm, square root of the duality gap, or other measure indicating distince from optimality.  This measure will be recorded and
2499           used for some termination tests.
2500 .  cnorm - the infeasibility of the current solution with regard to the constraints.
2501 -  steplength - multiple of the step direction added to the previous iterate.
2502 
2503    Output Parameters:
2504 .  reason - The termination reason, which can equal TAO_CONTINUE_ITERATING
2505 
2506    Options Database Key:
2507 .  -tao_monitor - Use the default monitor, which prints statistics to standard output
2508 
2509 .seealso TaoGetConvergedReason(), TaoDefaultMonitor(), TaoSetMonitor()
2510 
2511    Level: developer
2512 
2513 @*/
2514 PetscErrorCode TaoMonitor(Tao tao, PetscInt its, PetscReal f, PetscReal res, PetscReal cnorm, PetscReal steplength, TaoConvergedReason *reason)
2515 {
2516   PetscErrorCode ierr;
2517   PetscInt       i;
2518 
2519   PetscFunctionBegin;
2520   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2521   tao->fc = f;
2522   tao->residual = res;
2523   tao->cnorm = cnorm;
2524   tao->step = steplength;
2525   if (its == 0) {
2526     tao->cnorm0 = cnorm; tao->gnorm0 = res;
2527   }
2528   TaoLogConvergenceHistory(tao,f,res,cnorm,tao->ksp_its);
2529   if (PetscIsInfOrNanReal(f) || PetscIsInfOrNanReal(res)) SETERRQ(PETSC_COMM_SELF,1, "User provided compute function generated Inf or NaN");
2530   if (tao->ops->convergencetest) {
2531     ierr = (*tao->ops->convergencetest)(tao,tao->cnvP);CHKERRQ(ierr);
2532   }
2533   for (i=0;i<tao->numbermonitors;i++) {
2534     ierr = (*tao->monitor[i])(tao,tao->monitorcontext[i]);CHKERRQ(ierr);
2535   }
2536   *reason = tao->reason;
2537   PetscFunctionReturn(0);
2538 }
2539 
2540 #undef __FUNCT__
2541 #define __FUNCT__ "TaoSetConvergenceHistory"
2542 /*@
2543    TaoSetConvergenceHistory - Sets the array used to hold the convergence history.
2544 
2545    Logically Collective on Tao
2546 
2547    Input Parameters:
2548 +  tao - the Tao solver context
2549 .  obj   - array to hold objective value history
2550 .  resid - array to hold residual history
2551 .  cnorm - array to hold constraint violation history
2552 .  lits - integer array holds the number of linear iterations for each Tao iteration
2553 .  na  - size of obj, resid, and cnorm
2554 -  reset - PetscTrue indicates each new minimization resets the history counter to zero,
2555            else it continues storing new values for new minimizations after the old ones
2556 
2557    Notes:
2558    If set, TAO will fill the given arrays with the indicated
2559    information at each iteration.  If 'obj','resid','cnorm','lits' are
2560    *all* NULL then space (using size na, or 1000 if na is PETSC_DECIDE or
2561    PETSC_DEFAULT) is allocated for the history.
2562    If not all are NULL, then only the non-NULL information categories
2563    will be stored, the others will be ignored.
2564 
2565    Any convergence information after iteration number 'na' will not be stored.
2566 
2567    This routine is useful, e.g., when running a code for purposes
2568    of accurate performance monitoring, when no I/O should be done
2569    during the section of code that is being timed.
2570 
2571    Level: intermediate
2572 
2573 .seealso: TaoGetConvergenceHistory()
2574 
2575 @*/
2576 PetscErrorCode TaoSetConvergenceHistory(Tao tao, PetscReal *obj, PetscReal *resid, PetscReal *cnorm, PetscInt *lits, PetscInt na,PetscBool reset)
2577 {
2578   PetscErrorCode ierr;
2579 
2580   PetscFunctionBegin;
2581   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2582   if (obj) PetscValidScalarPointer(obj,2);
2583   if (resid) PetscValidScalarPointer(resid,3);
2584   if (cnorm) PetscValidScalarPointer(cnorm,4);
2585   if (lits) PetscValidIntPointer(lits,5);
2586 
2587   if (na == PETSC_DECIDE || na == PETSC_DEFAULT) na = 1000;
2588   if (!obj && !resid && !cnorm && !lits) {
2589     ierr = PetscCalloc1(na,&obj);CHKERRQ(ierr);
2590     ierr = PetscCalloc1(na,&resid);CHKERRQ(ierr);
2591     ierr = PetscCalloc1(na,&cnorm);CHKERRQ(ierr);
2592     ierr = PetscCalloc1(na,&lits);CHKERRQ(ierr);
2593     tao->hist_malloc=PETSC_TRUE;
2594   }
2595 
2596   tao->hist_obj = obj;
2597   tao->hist_resid = resid;
2598   tao->hist_cnorm = cnorm;
2599   tao->hist_lits = lits;
2600   tao->hist_max   = na;
2601   tao->hist_reset = reset;
2602   tao->hist_len = 0;
2603   PetscFunctionReturn(0);
2604 }
2605 
2606 #undef __FUNCT__
2607 #define __FUNCT__ "TaoGetConvergenceHistory"
2608 /*@C
2609    TaoGetConvergenceHistory - Gets the arrays used to hold the convergence history.
2610 
2611    Collective on Tao
2612 
2613    Input Parameter:
2614 .  tao - the Tao context
2615 
2616    Output Parameters:
2617 +  obj   - array used to hold objective value history
2618 .  resid - array used to hold residual history
2619 .  cnorm - array used to hold constraint violation history
2620 .  lits  - integer array used to hold linear solver iteration count
2621 -  nhist  - size of obj, resid, cnorm, and lits (will be less than or equal to na given in TaoSetHistory)
2622 
2623    Notes:
2624     This routine must be preceded by calls to TaoSetConvergenceHistory()
2625     and TaoSolve(), otherwise it returns useless information.
2626 
2627     The calling sequence for this routine in Fortran is
2628 $   call TaoGetConvergenceHistory(Tao tao, PetscInt nhist, PetscErrorCode ierr)
2629 
2630    This routine is useful, e.g., when running a code for purposes
2631    of accurate performance monitoring, when no I/O should be done
2632    during the section of code that is being timed.
2633 
2634    Level: advanced
2635 
2636 .seealso: TaoSetConvergenceHistory()
2637 
2638 @*/
2639 PetscErrorCode TaoGetConvergenceHistory(Tao tao, PetscReal **obj, PetscReal **resid, PetscReal **cnorm, PetscInt **lits, PetscInt *nhist)
2640 {
2641   PetscFunctionBegin;
2642   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2643   if (obj)   *obj   = tao->hist_obj;
2644   if (cnorm) *cnorm = tao->hist_cnorm;
2645   if (resid) *resid = tao->hist_resid;
2646   if (nhist) *nhist   = tao->hist_len;
2647   PetscFunctionReturn(0);
2648 }
2649 
2650 #undef __FUNCT__
2651 #define __FUNCT__ "TaoSetApplicationContext"
2652 /*@
2653    TaoSetApplicationContext - Sets the optional user-defined context for
2654    a solver.
2655 
2656    Logically Collective on Tao
2657 
2658    Input Parameters:
2659 +  tao  - the Tao context
2660 -  usrP - optional user context
2661 
2662    Level: intermediate
2663 
2664 .seealso: TaoGetApplicationContext(), TaoSetApplicationContext()
2665 @*/
2666 PetscErrorCode  TaoSetApplicationContext(Tao tao,void *usrP)
2667 {
2668   PetscFunctionBegin;
2669   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2670   tao->user = usrP;
2671   PetscFunctionReturn(0);
2672 }
2673 
2674 #undef __FUNCT__
2675 #define __FUNCT__ "TaoGetApplicationContext"
2676 /*@
2677    TaoGetApplicationContext - Gets the user-defined context for a
2678    TAO solvers.
2679 
2680    Not Collective
2681 
2682    Input Parameter:
2683 .  tao  - Tao context
2684 
2685    Output Parameter:
2686 .  usrP - user context
2687 
2688    Level: intermediate
2689 
2690 .seealso: TaoSetApplicationContext()
2691 @*/
2692 PetscErrorCode  TaoGetApplicationContext(Tao tao,void *usrP)
2693 {
2694   PetscFunctionBegin;
2695   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2696   *(void**)usrP = tao->user;
2697   PetscFunctionReturn(0);
2698 }
2699 
2700 #undef __FUNCT__
2701 #define __FUNCT__ "TaoSetGradientNorm"
2702 /*@
2703    TaoSetGradientNorm - Sets the matrix used to define the inner product that measures the size of the gradient.
2704 
2705    Collective on tao
2706 
2707    Input Parameters:
2708 +  tao  - the Tao context
2709 -  M    - gradient norm
2710 
2711    Level: beginner
2712 
2713 .seealso: TaoGetGradientNorm(), TaoGradientNorm()
2714 @*/
2715 PetscErrorCode  TaoSetGradientNorm(Tao tao, Mat M)
2716 {
2717   PetscErrorCode ierr;
2718 
2719   PetscFunctionBegin;
2720   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2721 
2722   if (tao->gradient_norm) {
2723     ierr = PetscObjectDereference((PetscObject)tao->gradient_norm);CHKERRQ(ierr);
2724     ierr = VecDestroy(&tao->gradient_norm_tmp);CHKERRQ(ierr);
2725   }
2726 
2727   ierr = PetscObjectReference((PetscObject)M);CHKERRQ(ierr);
2728   tao->gradient_norm = M;
2729   ierr = MatCreateVecs(M, NULL, &tao->gradient_norm_tmp);CHKERRQ(ierr);
2730   PetscFunctionReturn(0);
2731 }
2732 
2733 #undef __FUNCT__
2734 #define __FUNCT__ "TaoGetGradientNorm"
2735 /*@
2736    TaoGetGradientNorm - Returns the matrix used to define the inner product for measuring the size of the gradient.
2737 
2738    Not Collective
2739 
2740    Input Parameter:
2741 .  tao  - Tao context
2742 
2743    Output Parameter:
2744 .  M - gradient norm
2745 
2746    Level: beginner
2747 
2748 .seealso: TaoSetGradientNorm(), TaoGradientNorm()
2749 @*/
2750 PetscErrorCode  TaoGetGradientNorm(Tao tao, Mat *M)
2751 {
2752   PetscFunctionBegin;
2753   PetscValidHeaderSpecific(tao,TAO_CLASSID,1);
2754   *M = tao->gradient_norm;
2755   PetscFunctionReturn(0);
2756 }
2757 
2758 #undef __FUNCT__
2759 #define __FUNCT__ "TaoGradientNorm"
2760 /*c
2761    TaoGradientNorm - Compute the norm with respect to the inner product the user has set.
2762 
2763    Collective on tao
2764 
2765    Input Parameter:
2766 .  tao      - the Tao context
2767 .  gradient - the gradient to be computed
2768 .  norm     - the norm type
2769 
2770    Output Parameter:
2771 .  gnorm    - the gradient norm
2772 
2773    Level: developer
2774 
2775 .seealso: TaoSetGradientNorm(), TaoGetGradientNorm()
2776 @*/
2777 PetscErrorCode  TaoGradientNorm(Tao tao, Vec gradient, NormType type, PetscReal *gnorm)
2778 {
2779   PetscErrorCode ierr;
2780 
2781   PetscFunctionBegin;
2782   PetscValidHeaderSpecific(gradient,VEC_CLASSID,1);
2783 
2784   if (tao->gradient_norm) {
2785     PetscScalar gnorms;
2786 
2787     if (type != NORM_2) SETERRQ(PetscObjectComm((PetscObject)gradient), PETSC_ERR_ARG_WRONGSTATE, "Norm type must be NORM_2 if an inner product for the gradient norm is set.");
2788     ierr = MatMult(tao->gradient_norm, gradient, tao->gradient_norm_tmp);CHKERRQ(ierr);
2789     ierr = VecDot(gradient, tao->gradient_norm_tmp, &gnorms);CHKERRQ(ierr);
2790     *gnorm = PetscRealPart(PetscSqrtScalar(gnorms));
2791   } else {
2792     ierr = VecNorm(gradient, type, gnorm);CHKERRQ(ierr);
2793   }
2794   PetscFunctionReturn(0);
2795 }
2796 
2797 
2798