xref: /petsc/src/ts/interface/ts.c (revision c0517034d67f92a56cd022850bb947bfeaed5dde)
1 
2 #include <petsc/private/tsimpl.h>        /*I "petscts.h"  I*/
3 #include <petscdmshell.h>
4 #include <petscdmda.h>
5 #include <petscviewer.h>
6 #include <petscdraw.h>
7 
8 /* Logging support */
9 PetscClassId  TS_CLASSID, DMTS_CLASSID;
10 PetscLogEvent TS_AdjointStep, TS_Step, TS_PseudoComputeTimeStep, TS_FunctionEval, TS_JacobianEval;
11 
12 const char *const TSExactFinalTimeOptions[] = {"UNSPECIFIED","STEPOVER","INTERPOLATE","MATCHSTEP","TSExactFinalTimeOption","TS_EXACTFINALTIME_",0};
13 
14 struct _n_TSMonitorDrawCtx {
15   PetscViewer   viewer;
16   Vec           initialsolution;
17   PetscBool     showinitial;
18   PetscInt      howoften;  /* when > 0 uses step % howoften, when negative only final solution plotted */
19   PetscBool     showtimestepandtime;
20 };
21 
22 #undef __FUNCT__
23 #define __FUNCT__ "TSMonitorSetFromOptions"
24 /*@C
25    TSMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type indicated by the user
26 
27    Collective on TS
28 
29    Input Parameters:
30 +  ts - TS object you wish to monitor
31 .  name - the monitor type one is seeking
32 .  help - message indicating what monitoring is done
33 .  manual - manual page for the monitor
34 .  monitor - the monitor function
35 -  monitorsetup - a function that is called once ONLY if the user selected this monitor that may set additional features of the TS or PetscViewer objects
36 
37    Level: developer
38 
39 .seealso: PetscOptionsGetViewer(), PetscOptionsGetReal(), PetscOptionsHasName(), PetscOptionsGetString(),
40           PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsBool()
41           PetscOptionsInt(), PetscOptionsString(), PetscOptionsReal(), PetscOptionsBool(),
42           PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHead(),
43           PetscOptionsStringArray(),PetscOptionsRealArray(), PetscOptionsScalar(),
44           PetscOptionsBoolGroupBegin(), PetscOptionsBoolGroup(), PetscOptionsBoolGroupEnd(),
45           PetscOptionsFList(), PetscOptionsEList()
46 @*/
47 PetscErrorCode  TSMonitorSetFromOptions(TS ts,const char name[],const char help[], const char manual[],PetscErrorCode (*monitor)(TS,PetscInt,PetscReal,Vec,PetscViewerAndFormat*),PetscErrorCode (*monitorsetup)(TS,PetscViewerAndFormat*))
48 {
49   PetscErrorCode    ierr;
50   PetscViewer       viewer;
51   PetscViewerFormat format;
52   PetscBool         flg;
53 
54   PetscFunctionBegin;
55   ierr = PetscOptionsGetViewer(PetscObjectComm((PetscObject)ts),((PetscObject)ts)->prefix,name,&viewer,&format,&flg);CHKERRQ(ierr);
56   if (flg) {
57     PetscViewerAndFormat *vf;
58     ierr = PetscViewerAndFormatCreate(viewer,format,&vf);CHKERRQ(ierr);
59     ierr = PetscObjectDereference((PetscObject)viewer);CHKERRQ(ierr);
60     if (monitorsetup) {
61       ierr = (*monitorsetup)(ts,vf);CHKERRQ(ierr);
62     }
63     ierr = TSMonitorSet(ts,(PetscErrorCode (*)(TS,PetscInt,PetscReal,Vec,void*))monitor,vf,(PetscErrorCode (*)(void**))PetscViewerAndFormatDestroy);CHKERRQ(ierr);
64   }
65   PetscFunctionReturn(0);
66 }
67 
68 #undef __FUNCT__
69 #define __FUNCT__ "TSAdjointMonitorSetFromOptions"
70 /*@C
71    TSAdjointMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type indicated by the user
72 
73    Collective on TS
74 
75    Input Parameters:
76 +  ts - TS object you wish to monitor
77 .  name - the monitor type one is seeking
78 .  help - message indicating what monitoring is done
79 .  manual - manual page for the monitor
80 .  monitor - the monitor function
81 -  monitorsetup - a function that is called once ONLY if the user selected this monitor that may set additional features of the TS or PetscViewer objects
82 
83    Level: developer
84 
85 .seealso: PetscOptionsGetViewer(), PetscOptionsGetReal(), PetscOptionsHasName(), PetscOptionsGetString(),
86           PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsBool()
87           PetscOptionsInt(), PetscOptionsString(), PetscOptionsReal(), PetscOptionsBool(),
88           PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHead(),
89           PetscOptionsStringArray(),PetscOptionsRealArray(), PetscOptionsScalar(),
90           PetscOptionsBoolGroupBegin(), PetscOptionsBoolGroup(), PetscOptionsBoolGroupEnd(),
91           PetscOptionsFList(), PetscOptionsEList()
92 @*/
93 PetscErrorCode  TSAdjointMonitorSetFromOptions(TS ts,const char name[],const char help[], const char manual[],PetscErrorCode (*monitor)(TS,PetscInt,PetscReal,Vec,PetscInt,Vec*,Vec*,PetscViewerAndFormat*),PetscErrorCode (*monitorsetup)(TS,PetscViewerAndFormat*))
94 {
95   PetscErrorCode    ierr;
96   PetscViewer       viewer;
97   PetscViewerFormat format;
98   PetscBool         flg;
99 
100   PetscFunctionBegin;
101   ierr = PetscOptionsGetViewer(PetscObjectComm((PetscObject)ts),((PetscObject)ts)->prefix,name,&viewer,&format,&flg);CHKERRQ(ierr);
102   if (flg) {
103     PetscViewerAndFormat *vf;
104     ierr = PetscViewerAndFormatCreate(viewer,format,&vf);CHKERRQ(ierr);
105     ierr = PetscObjectDereference((PetscObject)viewer);CHKERRQ(ierr);
106     if (monitorsetup) {
107       ierr = (*monitorsetup)(ts,vf);CHKERRQ(ierr);
108     }
109     ierr = TSAdjointMonitorSet(ts,(PetscErrorCode (*)(TS,PetscInt,PetscReal,Vec,PetscInt,Vec*,Vec*,void*))monitor,vf,(PetscErrorCode (*)(void**))PetscViewerAndFormatDestroy);CHKERRQ(ierr);
110   }
111   PetscFunctionReturn(0);
112 }
113 
114 #undef __FUNCT__
115 #define __FUNCT__ "TSSetFromOptions"
116 /*@
117    TSSetFromOptions - Sets various TS parameters from user options.
118 
119    Collective on TS
120 
121    Input Parameter:
122 .  ts - the TS context obtained from TSCreate()
123 
124    Options Database Keys:
125 +  -ts_type <type> - TSEULER, TSBEULER, TSSUNDIALS, TSPSEUDO, TSCN, TSRK, TSTHETA, TSALPHA, TSGLLE, TSSSP, TSGLEE
126 .  -ts_save_trajectory - checkpoint the solution at each time-step
127 .  -ts_max_steps <maxsteps> - maximum number of time-steps to take
128 .  -ts_final_time <time> - maximum time to compute to
129 .  -ts_dt <dt> - initial time step
130 .  -ts_exact_final_time <stepover,interpolate,matchstep> whether to stop at the exact given final time and how to compute the solution at that ti,e
131 .  -ts_max_snes_failures <maxfailures> - Maximum number of nonlinear solve failures allowed
132 .  -ts_max_reject <maxrejects> - Maximum number of step rejections before step fails
133 .  -ts_error_if_step_fails <true,false> - Error if no step succeeds
134 .  -ts_rtol <rtol> - relative tolerance for local truncation error
135 .  -ts_atol <atol> Absolute tolerance for local truncation error
136 .  -ts_adjoint_solve <yes,no> After solving the ODE/DAE solve the adjoint problem (requires -ts_save_trajectory)
137 .  -ts_fd_color - Use finite differences with coloring to compute IJacobian
138 .  -ts_monitor - print information at each timestep
139 .  -ts_monitor_lg_solution - Monitor solution graphically
140 .  -ts_monitor_lg_error - Monitor error graphically
141 .  -ts_monitor_lg_timestep - Monitor timestep size graphically
142 .  -ts_monitor_lg_snes_iterations - Monitor number nonlinear iterations for each timestep graphically
143 .  -ts_monitor_lg_ksp_iterations - Monitor number nonlinear iterations for each timestep graphically
144 .  -ts_monitor_sp_eig - Monitor eigenvalues of linearized operator graphically
145 .  -ts_monitor_draw_solution - Monitor solution graphically
146 .  -ts_monitor_draw_solution_phase  <xleft,yleft,xright,yright> - Monitor solution graphically with phase diagram, requires problem with exactly 2 degrees of freedom
147 .  -ts_monitor_draw_error - Monitor error graphically, requires use to have provided TSSetSolutionFunction()
148 .  -ts_monitor_solution [ascii binary draw][:filename][:viewerformat] - monitors the solution at each timestep
149 .  -ts_monitor_solution_vtk <filename.vts> - Save each time step to a binary file, use filename-%%03D.vts
150 .  -ts_monitor_envelope - determine maximum and minimum value of each component of the solution over the solution time
151 .  -ts_adjoint_monitor - print information at each adjoint time step
152 -  -ts_adjoint_monitor_draw_sensi - monitor the sensitivity of the first cost function wrt initial conditions (lambda[0]) graphically
153 
154    Developer Note: We should unify all the -ts_monitor options in the way that -xxx_view has been unified
155 
156    Level: beginner
157 
158 .keywords: TS, timestep, set, options, database
159 
160 .seealso: TSGetType()
161 @*/
162 PetscErrorCode  TSSetFromOptions(TS ts)
163 {
164   PetscBool              opt,flg,tflg;
165   PetscErrorCode         ierr;
166   char                   monfilename[PETSC_MAX_PATH_LEN];
167   PetscReal              time_step;
168   TSExactFinalTimeOption eftopt;
169   char                   dir[16];
170   TSIFunction            ifun;
171   const char             *defaultType;
172   char                   typeName[256];
173 
174   PetscFunctionBegin;
175   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
176 
177   ierr = TSRegisterAll();CHKERRQ(ierr);
178   ierr = TSGetIFunction(ts,NULL,&ifun,NULL);CHKERRQ(ierr);
179 
180   ierr = PetscObjectOptionsBegin((PetscObject)ts);CHKERRQ(ierr);
181   if (((PetscObject)ts)->type_name)
182     defaultType = ((PetscObject)ts)->type_name;
183   else
184     defaultType = ifun ? TSBEULER : TSEULER;
185   ierr = PetscOptionsFList("-ts_type","TS method","TSSetType",TSList,defaultType,typeName,256,&opt);CHKERRQ(ierr);
186   if (opt) {
187     ierr = TSSetType(ts,typeName);CHKERRQ(ierr);
188   } else {
189     ierr = TSSetType(ts,defaultType);CHKERRQ(ierr);
190   }
191 
192   /* Handle generic TS options */
193   ierr = PetscOptionsInt("-ts_max_steps","Maximum number of time steps","TSSetDuration",ts->max_steps,&ts->max_steps,NULL);CHKERRQ(ierr);
194   ierr = PetscOptionsReal("-ts_final_time","Time to run to","TSSetDuration",ts->max_time,&ts->max_time,NULL);CHKERRQ(ierr);
195   ierr = PetscOptionsReal("-ts_init_time","Initial time","TSSetTime",ts->ptime,&ts->ptime,NULL);CHKERRQ(ierr);
196   ierr = PetscOptionsReal("-ts_dt","Initial time step","TSSetTimeStep",ts->time_step,&time_step,&flg);CHKERRQ(ierr);
197   if (flg) {ierr = TSSetTimeStep(ts,time_step);CHKERRQ(ierr);}
198   ierr = PetscOptionsEnum("-ts_exact_final_time","Option for handling of final time step","TSSetExactFinalTime",TSExactFinalTimeOptions,(PetscEnum)ts->exact_final_time,(PetscEnum*)&eftopt,&flg);CHKERRQ(ierr);
199   if (flg) {ierr = TSSetExactFinalTime(ts,eftopt);CHKERRQ(ierr);}
200   ierr = PetscOptionsInt("-ts_max_snes_failures","Maximum number of nonlinear solve failures","TSSetMaxSNESFailures",ts->max_snes_failures,&ts->max_snes_failures,NULL);CHKERRQ(ierr);
201   ierr = PetscOptionsInt("-ts_max_reject","Maximum number of step rejections before step fails","TSSetMaxStepRejections",ts->max_reject,&ts->max_reject,NULL);CHKERRQ(ierr);
202   ierr = PetscOptionsBool("-ts_error_if_step_fails","Error if no step succeeds","TSSetErrorIfStepFails",ts->errorifstepfailed,&ts->errorifstepfailed,NULL);CHKERRQ(ierr);
203   ierr = PetscOptionsReal("-ts_rtol","Relative tolerance for local truncation error","TSSetTolerances",ts->rtol,&ts->rtol,NULL);CHKERRQ(ierr);
204   ierr = PetscOptionsReal("-ts_atol","Absolute tolerance for local truncation error","TSSetTolerances",ts->atol,&ts->atol,NULL);CHKERRQ(ierr);
205 
206 #if defined(PETSC_HAVE_SAWS)
207   {
208   PetscBool set;
209   flg  = PETSC_FALSE;
210   ierr = PetscOptionsBool("-ts_saws_block","Block for SAWs memory snooper at end of TSSolve","PetscObjectSAWsBlock",((PetscObject)ts)->amspublishblock,&flg,&set);CHKERRQ(ierr);
211   if (set) {
212     ierr = PetscObjectSAWsSetBlock((PetscObject)ts,flg);CHKERRQ(ierr);
213   }
214   }
215 #endif
216 
217   /* Monitor options */
218   ierr = TSMonitorSetFromOptions(ts,"-ts_monitor","Monitor time and timestep size","TSMonitorDefault",TSMonitorDefault,NULL);CHKERRQ(ierr);
219   ierr = TSMonitorSetFromOptions(ts,"-ts_monitor_solution","View the solution at each timestep","TSMonitorSolution",TSMonitorSolution,NULL);CHKERRQ(ierr);
220   ierr = TSAdjointMonitorSetFromOptions(ts,"-ts_adjoint_monitor","Monitor adjoint timestep size","TSAdjointMonitorDefault",TSAdjointMonitorDefault,NULL);CHKERRQ(ierr);
221 
222   ierr = PetscOptionsString("-ts_monitor_python","Use Python function","TSMonitorSet",0,monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
223   if (flg) {ierr = PetscPythonMonitorSet((PetscObject)ts,monfilename);CHKERRQ(ierr);}
224 
225   ierr = PetscOptionsName("-ts_monitor_lg_solution","Monitor solution graphically","TSMonitorLGSolution",&opt);CHKERRQ(ierr);
226   if (opt) {
227     TSMonitorLGCtx ctx;
228     PetscInt       howoften = 1;
229 
230     ierr = PetscOptionsInt("-ts_monitor_lg_solution","Monitor solution graphically","TSMonitorLGSolution",howoften,&howoften,NULL);CHKERRQ(ierr);
231     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
232     ierr = TSMonitorSet(ts,TSMonitorLGSolution,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
233   }
234 
235   ierr = PetscOptionsName("-ts_monitor_lg_error","Monitor error graphically","TSMonitorLGError",&opt);CHKERRQ(ierr);
236   if (opt) {
237     TSMonitorLGCtx ctx;
238     PetscInt       howoften = 1;
239 
240     ierr = PetscOptionsInt("-ts_monitor_lg_error","Monitor error graphically","TSMonitorLGError",howoften,&howoften,NULL);CHKERRQ(ierr);
241     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
242     ierr = TSMonitorSet(ts,TSMonitorLGError,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
243   }
244 
245   ierr = PetscOptionsName("-ts_monitor_lg_timestep","Monitor timestep size graphically","TSMonitorLGTimeStep",&opt);CHKERRQ(ierr);
246   if (opt) {
247     TSMonitorLGCtx ctx;
248     PetscInt       howoften = 1;
249 
250     ierr = PetscOptionsInt("-ts_monitor_lg_timestep","Monitor timestep size graphically","TSMonitorLGTimeStep",howoften,&howoften,NULL);CHKERRQ(ierr);
251     ierr = TSMonitorLGCtxCreate(PetscObjectComm((PetscObject)ts),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
252     ierr = TSMonitorSet(ts,TSMonitorLGTimeStep,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
253   }
254   ierr = PetscOptionsName("-ts_monitor_lg_snes_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGSNESIterations",&opt);CHKERRQ(ierr);
255   if (opt) {
256     TSMonitorLGCtx ctx;
257     PetscInt       howoften = 1;
258 
259     ierr = PetscOptionsInt("-ts_monitor_lg_snes_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGSNESIterations",howoften,&howoften,NULL);CHKERRQ(ierr);
260     ierr = TSMonitorLGCtxCreate(PetscObjectComm((PetscObject)ts),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
261     ierr = TSMonitorSet(ts,TSMonitorLGSNESIterations,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
262   }
263   ierr = PetscOptionsName("-ts_monitor_lg_ksp_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGKSPIterations",&opt);CHKERRQ(ierr);
264   if (opt) {
265     TSMonitorLGCtx ctx;
266     PetscInt       howoften = 1;
267 
268     ierr = PetscOptionsInt("-ts_monitor_lg_ksp_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGKSPIterations",howoften,&howoften,NULL);CHKERRQ(ierr);
269     ierr = TSMonitorLGCtxCreate(PetscObjectComm((PetscObject)ts),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
270     ierr = TSMonitorSet(ts,TSMonitorLGKSPIterations,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
271   }
272   ierr = PetscOptionsName("-ts_monitor_sp_eig","Monitor eigenvalues of linearized operator graphically","TSMonitorSPEig",&opt);CHKERRQ(ierr);
273   if (opt) {
274     TSMonitorSPEigCtx ctx;
275     PetscInt          howoften = 1;
276 
277     ierr = PetscOptionsInt("-ts_monitor_sp_eig","Monitor eigenvalues of linearized operator graphically","TSMonitorSPEig",howoften,&howoften,NULL);CHKERRQ(ierr);
278     ierr = TSMonitorSPEigCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
279     ierr = TSMonitorSet(ts,TSMonitorSPEig,ctx,(PetscErrorCode (*)(void**))TSMonitorSPEigCtxDestroy);CHKERRQ(ierr);
280   }
281   opt  = PETSC_FALSE;
282   ierr = PetscOptionsName("-ts_monitor_draw_solution","Monitor solution graphically","TSMonitorDrawSolution",&opt);CHKERRQ(ierr);
283   if (opt) {
284     TSMonitorDrawCtx ctx;
285     PetscInt         howoften = 1;
286 
287     ierr = PetscOptionsInt("-ts_monitor_draw_solution","Monitor solution graphically","TSMonitorDrawSolution",howoften,&howoften,NULL);CHKERRQ(ierr);
288     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
289     ierr = TSMonitorSet(ts,TSMonitorDrawSolution,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
290   }
291   opt  = PETSC_FALSE;
292   ierr = PetscOptionsName("-ts_adjoint_monitor_draw_sensi","Monitor adjoint sensitivities (lambda only) graphically","TSAdjointMonitorDrawSensi",&opt);CHKERRQ(ierr);
293   if (opt) {
294     TSMonitorDrawCtx ctx;
295     PetscInt         howoften = 1;
296 
297     ierr = PetscOptionsInt("-ts_adjoint_monitor_draw_sensi","Monitor adjoint sensitivities (lambda only) graphically","TSAdjointMonitorDrawSensi",howoften,&howoften,NULL);CHKERRQ(ierr);
298     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
299     ierr = TSAdjointMonitorSet(ts,TSAdjointMonitorDrawSensi,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
300   }
301   opt  = PETSC_FALSE;
302   ierr = PetscOptionsName("-ts_monitor_draw_solution_phase","Monitor solution graphically","TSMonitorDrawSolutionPhase",&opt);CHKERRQ(ierr);
303   if (opt) {
304     TSMonitorDrawCtx ctx;
305     PetscReal        bounds[4];
306     PetscInt         n = 4;
307     PetscDraw        draw;
308     PetscDrawAxis    axis;
309 
310     ierr = PetscOptionsRealArray("-ts_monitor_draw_solution_phase","Monitor solution graphically","TSMonitorDrawSolutionPhase",bounds,&n,NULL);CHKERRQ(ierr);
311     if (n != 4) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Must provide bounding box of phase field");
312     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,1,&ctx);CHKERRQ(ierr);
313     ierr = PetscViewerDrawGetDraw(ctx->viewer,0,&draw);CHKERRQ(ierr);
314     ierr = PetscViewerDrawGetDrawAxis(ctx->viewer,0,&axis);CHKERRQ(ierr);
315     ierr = PetscDrawAxisSetLimits(axis,bounds[0],bounds[2],bounds[1],bounds[3]);CHKERRQ(ierr);
316     ierr = PetscDrawAxisSetLabels(axis,"Phase Diagram","Variable 1","Variable 2");CHKERRQ(ierr);
317     ierr = TSMonitorSet(ts,TSMonitorDrawSolutionPhase,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
318   }
319   opt  = PETSC_FALSE;
320   ierr = PetscOptionsName("-ts_monitor_draw_error","Monitor error graphically","TSMonitorDrawError",&opt);CHKERRQ(ierr);
321   if (opt) {
322     TSMonitorDrawCtx ctx;
323     PetscInt         howoften = 1;
324 
325     ierr = PetscOptionsInt("-ts_monitor_draw_error","Monitor error graphically","TSMonitorDrawError",howoften,&howoften,NULL);CHKERRQ(ierr);
326     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
327     ierr = TSMonitorSet(ts,TSMonitorDrawError,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
328   }
329 
330   opt  = PETSC_FALSE;
331   ierr = PetscOptionsString("-ts_monitor_solution_vtk","Save each time step to a binary file, use filename-%%03D.vts","TSMonitorSolutionVTK",0,monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
332   if (flg) {
333     const char *ptr,*ptr2;
334     char       *filetemplate;
335     if (!monfilename[0]) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"-ts_monitor_solution_vtk requires a file template, e.g. filename-%%03D.vts");
336     /* Do some cursory validation of the input. */
337     ierr = PetscStrstr(monfilename,"%",(char**)&ptr);CHKERRQ(ierr);
338     if (!ptr) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"-ts_monitor_solution_vtk requires a file template, e.g. filename-%%03D.vts");
339     for (ptr++; ptr && *ptr; ptr++) {
340       ierr = PetscStrchr("DdiouxX",*ptr,(char**)&ptr2);CHKERRQ(ierr);
341       if (!ptr2 && (*ptr < '0' || '9' < *ptr)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Invalid file template argument to -ts_monitor_solution_vtk, should look like filename-%%03D.vts");
342       if (ptr2) break;
343     }
344     ierr = PetscStrallocpy(monfilename,&filetemplate);CHKERRQ(ierr);
345     ierr = TSMonitorSet(ts,TSMonitorSolutionVTK,filetemplate,(PetscErrorCode (*)(void**))TSMonitorSolutionVTKDestroy);CHKERRQ(ierr);
346   }
347 
348   ierr = PetscOptionsString("-ts_monitor_dmda_ray","Display a ray of the solution","None","y=0",dir,16,&flg);CHKERRQ(ierr);
349   if (flg) {
350     TSMonitorDMDARayCtx *rayctx;
351     int                  ray = 0;
352     DMDADirection        ddir;
353     DM                   da;
354     PetscMPIInt          rank;
355 
356     if (dir[1] != '=') SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Unknown ray %s",dir);
357     if (dir[0] == 'x') ddir = DMDA_X;
358     else if (dir[0] == 'y') ddir = DMDA_Y;
359     else SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Unknown ray %s",dir);
360     sscanf(dir+2,"%d",&ray);
361 
362     ierr = PetscInfo2(((PetscObject)ts),"Displaying DMDA ray %c = %D\n",dir[0],ray);CHKERRQ(ierr);
363     ierr = PetscNew(&rayctx);CHKERRQ(ierr);
364     ierr = TSGetDM(ts,&da);CHKERRQ(ierr);
365     ierr = DMDAGetRay(da,ddir,ray,&rayctx->ray,&rayctx->scatter);CHKERRQ(ierr);
366     ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)ts),&rank);CHKERRQ(ierr);
367     if (!rank) {
368       ierr = PetscViewerDrawOpen(PETSC_COMM_SELF,0,0,0,0,600,300,&rayctx->viewer);CHKERRQ(ierr);
369     }
370     rayctx->lgctx = NULL;
371     ierr = TSMonitorSet(ts,TSMonitorDMDARay,rayctx,TSMonitorDMDARayDestroy);CHKERRQ(ierr);
372   }
373   ierr = PetscOptionsString("-ts_monitor_lg_dmda_ray","Display a ray of the solution","None","x=0",dir,16,&flg);CHKERRQ(ierr);
374   if (flg) {
375     TSMonitorDMDARayCtx *rayctx;
376     int                 ray = 0;
377     DMDADirection       ddir;
378     DM                  da;
379     PetscInt            howoften = 1;
380 
381     if (dir[1] != '=') SETERRQ1(PetscObjectComm((PetscObject) ts), PETSC_ERR_ARG_WRONG, "Malformed ray %s", dir);
382     if      (dir[0] == 'x') ddir = DMDA_X;
383     else if (dir[0] == 'y') ddir = DMDA_Y;
384     else SETERRQ1(PetscObjectComm((PetscObject) ts), PETSC_ERR_ARG_WRONG, "Unknown ray direction %s", dir);
385     sscanf(dir+2, "%d", &ray);
386 
387     ierr = PetscInfo2(((PetscObject) ts),"Displaying LG DMDA ray %c = %D\n", dir[0], ray);CHKERRQ(ierr);
388     ierr = PetscNew(&rayctx);CHKERRQ(ierr);
389     ierr = TSGetDM(ts, &da);CHKERRQ(ierr);
390     ierr = DMDAGetRay(da, ddir, ray, &rayctx->ray, &rayctx->scatter);CHKERRQ(ierr);
391     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,600,400,howoften,&rayctx->lgctx);CHKERRQ(ierr);
392     ierr = TSMonitorSet(ts, TSMonitorLGDMDARay, rayctx, TSMonitorDMDARayDestroy);CHKERRQ(ierr);
393   }
394 
395   ierr = PetscOptionsName("-ts_monitor_envelope","Monitor maximum and minimum value of each component of the solution","TSMonitorEnvelope",&opt);CHKERRQ(ierr);
396   if (opt) {
397     TSMonitorEnvelopeCtx ctx;
398 
399     ierr = TSMonitorEnvelopeCtxCreate(ts,&ctx);CHKERRQ(ierr);
400     ierr = TSMonitorSet(ts,TSMonitorEnvelope,ctx,(PetscErrorCode (*)(void**))TSMonitorEnvelopeCtxDestroy);CHKERRQ(ierr);
401   }
402 
403   flg  = PETSC_FALSE;
404   ierr = PetscOptionsBool("-ts_fd_color", "Use finite differences with coloring to compute IJacobian", "TSComputeJacobianDefaultColor", flg, &flg, NULL);CHKERRQ(ierr);
405   if (flg) {
406     DM   dm;
407     DMTS tdm;
408 
409     ierr = TSGetDM(ts, &dm);CHKERRQ(ierr);
410     ierr = DMGetDMTS(dm, &tdm);CHKERRQ(ierr);
411     tdm->ijacobianctx = NULL;
412     ierr = TSSetIJacobian(ts, NULL, NULL, TSComputeIJacobianDefaultColor, 0);CHKERRQ(ierr);
413     ierr = PetscInfo(ts, "Setting default finite difference coloring Jacobian matrix\n");CHKERRQ(ierr);
414   }
415 
416   if (ts->adapt) {
417     ierr = TSAdaptSetFromOptions(PetscOptionsObject,ts->adapt);CHKERRQ(ierr);
418   }
419 
420   /* Handle specific TS options */
421   if (ts->ops->setfromoptions) {
422     ierr = (*ts->ops->setfromoptions)(PetscOptionsObject,ts);CHKERRQ(ierr);
423   }
424 
425   /* TS trajectory must be set after TS, since it may use some TS options above */
426   tflg = ts->trajectory ? PETSC_TRUE : PETSC_FALSE;
427   ierr = PetscOptionsBool("-ts_save_trajectory","Save the solution at each timestep","TSSetSaveTrajectory",tflg,&tflg,NULL);CHKERRQ(ierr);
428   if (tflg) {
429     ierr = TSSetSaveTrajectory(ts);CHKERRQ(ierr);
430   }
431   tflg = ts->adjoint_solve ? PETSC_TRUE : PETSC_FALSE;
432   ierr = PetscOptionsBool("-ts_adjoint_solve","Solve the adjoint problem immediately after solving the forward problem","",tflg,&tflg,&flg);CHKERRQ(ierr);
433   if (flg) {
434     ierr = TSSetSaveTrajectory(ts);CHKERRQ(ierr);
435     ts->adjoint_solve = tflg;
436   }
437 
438   /* process any options handlers added with PetscObjectAddOptionsHandler() */
439   ierr = PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)ts);CHKERRQ(ierr);
440   ierr = PetscOptionsEnd();CHKERRQ(ierr);
441 
442   if (ts->trajectory) {
443     ierr = TSTrajectorySetFromOptions(ts->trajectory,ts);CHKERRQ(ierr);
444   }
445 
446   ierr = TSGetSNES(ts,&ts->snes);CHKERRQ(ierr);
447   if (ts->problem_type == TS_LINEAR) {ierr = SNESSetType(ts->snes,SNESKSPONLY);CHKERRQ(ierr);}
448   ierr = SNESSetFromOptions(ts->snes);CHKERRQ(ierr);
449   PetscFunctionReturn(0);
450 }
451 
452 #undef __FUNCT__
453 #define __FUNCT__ "TSSetSaveTrajectory"
454 /*@
455    TSSetSaveTrajectory - Causes the TS to save its solutions as it iterates forward in time in a TSTrajectory object
456 
457    Collective on TS
458 
459    Input Parameters:
460 .  ts - the TS context obtained from TSCreate()
461 
462 Note: This routine should be called after all TS options have been set
463 
464    Level: intermediate
465 
466 .seealso: TSGetTrajectory(), TSAdjointSolve()
467 
468 .keywords: TS, set, checkpoint,
469 @*/
470 PetscErrorCode  TSSetSaveTrajectory(TS ts)
471 {
472   PetscErrorCode ierr;
473 
474   PetscFunctionBegin;
475   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
476   if (!ts->trajectory) {
477     ierr = TSTrajectoryCreate(PetscObjectComm((PetscObject)ts),&ts->trajectory);CHKERRQ(ierr);
478     ierr = TSTrajectorySetFromOptions(ts->trajectory,ts);CHKERRQ(ierr);
479   }
480   PetscFunctionReturn(0);
481 }
482 
483 #undef __FUNCT__
484 #define __FUNCT__ "TSComputeRHSJacobian"
485 /*@
486    TSComputeRHSJacobian - Computes the Jacobian matrix that has been
487       set with TSSetRHSJacobian().
488 
489    Collective on TS and Vec
490 
491    Input Parameters:
492 +  ts - the TS context
493 .  t - current timestep
494 -  U - input vector
495 
496    Output Parameters:
497 +  A - Jacobian matrix
498 .  B - optional preconditioning matrix
499 -  flag - flag indicating matrix structure
500 
501    Notes:
502    Most users should not need to explicitly call this routine, as it
503    is used internally within the nonlinear solvers.
504 
505    See KSPSetOperators() for important information about setting the
506    flag parameter.
507 
508    Level: developer
509 
510 .keywords: SNES, compute, Jacobian, matrix
511 
512 .seealso:  TSSetRHSJacobian(), KSPSetOperators()
513 @*/
514 PetscErrorCode  TSComputeRHSJacobian(TS ts,PetscReal t,Vec U,Mat A,Mat B)
515 {
516   PetscErrorCode ierr;
517   PetscObjectState Ustate;
518   DM             dm;
519   DMTS           tsdm;
520   TSRHSJacobian  rhsjacobianfunc;
521   void           *ctx;
522   TSIJacobian    ijacobianfunc;
523   TSRHSFunction  rhsfunction;
524 
525   PetscFunctionBegin;
526   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
527   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
528   PetscCheckSameComm(ts,1,U,3);
529   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
530   ierr = DMGetDMTS(dm,&tsdm);CHKERRQ(ierr);
531   ierr = DMTSGetRHSJacobian(dm,&rhsjacobianfunc,&ctx);CHKERRQ(ierr);
532   ierr = DMTSGetIJacobian(dm,&ijacobianfunc,NULL);CHKERRQ(ierr);
533   ierr = DMTSGetRHSFunction(dm,&rhsfunction,&ctx);CHKERRQ(ierr);
534   ierr = PetscObjectStateGet((PetscObject)U,&Ustate);CHKERRQ(ierr);
535   if (ts->rhsjacobian.time == t && (ts->problem_type == TS_LINEAR || (ts->rhsjacobian.X == U && ts->rhsjacobian.Xstate == Ustate)) && (rhsfunction != TSComputeRHSFunctionLinear)) {
536     PetscFunctionReturn(0);
537   }
538 
539   if (!rhsjacobianfunc && !ijacobianfunc) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSJacobian() and / or TSSetIJacobian()");
540 
541   if (ts->rhsjacobian.reuse) {
542     ierr = MatShift(A,-ts->rhsjacobian.shift);CHKERRQ(ierr);
543     ierr = MatScale(A,1./ts->rhsjacobian.scale);CHKERRQ(ierr);
544     if (A != B) {
545       ierr = MatShift(B,-ts->rhsjacobian.shift);CHKERRQ(ierr);
546       ierr = MatScale(B,1./ts->rhsjacobian.scale);CHKERRQ(ierr);
547     }
548     ts->rhsjacobian.shift = 0;
549     ts->rhsjacobian.scale = 1.;
550   }
551 
552   if (rhsjacobianfunc) {
553     PetscBool missing;
554     ierr = PetscLogEventBegin(TS_JacobianEval,ts,U,A,B);CHKERRQ(ierr);
555     PetscStackPush("TS user Jacobian function");
556     ierr = (*rhsjacobianfunc)(ts,t,U,A,B,ctx);CHKERRQ(ierr);
557     PetscStackPop;
558     ierr = PetscLogEventEnd(TS_JacobianEval,ts,U,A,B);CHKERRQ(ierr);
559     if (A) {
560       ierr = MatMissingDiagonal(A,&missing,NULL);CHKERRQ(ierr);
561       if (missing) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Amat passed to TSSetRHSJacobian() must have all diagonal entries set, if they are zero you must still set them with a zero value");
562     }
563     if (B && B != A) {
564       ierr = MatMissingDiagonal(B,&missing,NULL);CHKERRQ(ierr);
565       if (missing) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Bmat passed to TSSetRHSJacobian() must have all diagonal entries set, if they are zero you must still set them with a zero value");
566     }
567   } else {
568     ierr = MatZeroEntries(A);CHKERRQ(ierr);
569     if (A != B) {ierr = MatZeroEntries(B);CHKERRQ(ierr);}
570   }
571   ts->rhsjacobian.time       = t;
572   ts->rhsjacobian.X          = U;
573   ierr                       = PetscObjectStateGet((PetscObject)U,&ts->rhsjacobian.Xstate);CHKERRQ(ierr);
574   PetscFunctionReturn(0);
575 }
576 
577 #undef __FUNCT__
578 #define __FUNCT__ "TSComputeRHSFunction"
579 /*@
580    TSComputeRHSFunction - Evaluates the right-hand-side function.
581 
582    Collective on TS and Vec
583 
584    Input Parameters:
585 +  ts - the TS context
586 .  t - current time
587 -  U - state vector
588 
589    Output Parameter:
590 .  y - right hand side
591 
592    Note:
593    Most users should not need to explicitly call this routine, as it
594    is used internally within the nonlinear solvers.
595 
596    Level: developer
597 
598 .keywords: TS, compute
599 
600 .seealso: TSSetRHSFunction(), TSComputeIFunction()
601 @*/
602 PetscErrorCode TSComputeRHSFunction(TS ts,PetscReal t,Vec U,Vec y)
603 {
604   PetscErrorCode ierr;
605   TSRHSFunction  rhsfunction;
606   TSIFunction    ifunction;
607   void           *ctx;
608   DM             dm;
609 
610   PetscFunctionBegin;
611   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
612   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
613   PetscValidHeaderSpecific(y,VEC_CLASSID,4);
614   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
615   ierr = DMTSGetRHSFunction(dm,&rhsfunction,&ctx);CHKERRQ(ierr);
616   ierr = DMTSGetIFunction(dm,&ifunction,NULL);CHKERRQ(ierr);
617 
618   if (!rhsfunction && !ifunction) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSFunction() and / or TSSetIFunction()");
619 
620   ierr = PetscLogEventBegin(TS_FunctionEval,ts,U,y,0);CHKERRQ(ierr);
621   if (rhsfunction) {
622     PetscStackPush("TS user right-hand-side function");
623     ierr = (*rhsfunction)(ts,t,U,y,ctx);CHKERRQ(ierr);
624     PetscStackPop;
625   } else {
626     ierr = VecZeroEntries(y);CHKERRQ(ierr);
627   }
628 
629   ierr = PetscLogEventEnd(TS_FunctionEval,ts,U,y,0);CHKERRQ(ierr);
630   PetscFunctionReturn(0);
631 }
632 
633 #undef __FUNCT__
634 #define __FUNCT__ "TSComputeSolutionFunction"
635 /*@
636    TSComputeSolutionFunction - Evaluates the solution function.
637 
638    Collective on TS and Vec
639 
640    Input Parameters:
641 +  ts - the TS context
642 -  t - current time
643 
644    Output Parameter:
645 .  U - the solution
646 
647    Note:
648    Most users should not need to explicitly call this routine, as it
649    is used internally within the nonlinear solvers.
650 
651    Level: developer
652 
653 .keywords: TS, compute
654 
655 .seealso: TSSetSolutionFunction(), TSSetRHSFunction(), TSComputeIFunction()
656 @*/
657 PetscErrorCode TSComputeSolutionFunction(TS ts,PetscReal t,Vec U)
658 {
659   PetscErrorCode     ierr;
660   TSSolutionFunction solutionfunction;
661   void               *ctx;
662   DM                 dm;
663 
664   PetscFunctionBegin;
665   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
666   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
667   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
668   ierr = DMTSGetSolutionFunction(dm,&solutionfunction,&ctx);CHKERRQ(ierr);
669 
670   if (solutionfunction) {
671     PetscStackPush("TS user solution function");
672     ierr = (*solutionfunction)(ts,t,U,ctx);CHKERRQ(ierr);
673     PetscStackPop;
674   }
675   PetscFunctionReturn(0);
676 }
677 #undef __FUNCT__
678 #define __FUNCT__ "TSComputeForcingFunction"
679 /*@
680    TSComputeForcingFunction - Evaluates the forcing function.
681 
682    Collective on TS and Vec
683 
684    Input Parameters:
685 +  ts - the TS context
686 -  t - current time
687 
688    Output Parameter:
689 .  U - the function value
690 
691    Note:
692    Most users should not need to explicitly call this routine, as it
693    is used internally within the nonlinear solvers.
694 
695    Level: developer
696 
697 .keywords: TS, compute
698 
699 .seealso: TSSetSolutionFunction(), TSSetRHSFunction(), TSComputeIFunction()
700 @*/
701 PetscErrorCode TSComputeForcingFunction(TS ts,PetscReal t,Vec U)
702 {
703   PetscErrorCode     ierr, (*forcing)(TS,PetscReal,Vec,void*);
704   void               *ctx;
705   DM                 dm;
706 
707   PetscFunctionBegin;
708   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
709   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
710   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
711   ierr = DMTSGetForcingFunction(dm,&forcing,&ctx);CHKERRQ(ierr);
712 
713   if (forcing) {
714     PetscStackPush("TS user forcing function");
715     ierr = (*forcing)(ts,t,U,ctx);CHKERRQ(ierr);
716     PetscStackPop;
717   }
718   PetscFunctionReturn(0);
719 }
720 
721 #undef __FUNCT__
722 #define __FUNCT__ "TSGetRHSVec_Private"
723 static PetscErrorCode TSGetRHSVec_Private(TS ts,Vec *Frhs)
724 {
725   Vec            F;
726   PetscErrorCode ierr;
727 
728   PetscFunctionBegin;
729   *Frhs = NULL;
730   ierr  = TSGetIFunction(ts,&F,NULL,NULL);CHKERRQ(ierr);
731   if (!ts->Frhs) {
732     ierr = VecDuplicate(F,&ts->Frhs);CHKERRQ(ierr);
733   }
734   *Frhs = ts->Frhs;
735   PetscFunctionReturn(0);
736 }
737 
738 #undef __FUNCT__
739 #define __FUNCT__ "TSGetRHSMats_Private"
740 static PetscErrorCode TSGetRHSMats_Private(TS ts,Mat *Arhs,Mat *Brhs)
741 {
742   Mat            A,B;
743   PetscErrorCode ierr;
744 
745   PetscFunctionBegin;
746   if (Arhs) *Arhs = NULL;
747   if (Brhs) *Brhs = NULL;
748   ierr = TSGetIJacobian(ts,&A,&B,NULL,NULL);CHKERRQ(ierr);
749   if (Arhs) {
750     if (!ts->Arhs) {
751       ierr = MatDuplicate(A,MAT_DO_NOT_COPY_VALUES,&ts->Arhs);CHKERRQ(ierr);
752     }
753     *Arhs = ts->Arhs;
754   }
755   if (Brhs) {
756     if (!ts->Brhs) {
757       if (A != B) {
758         ierr = MatDuplicate(B,MAT_DO_NOT_COPY_VALUES,&ts->Brhs);CHKERRQ(ierr);
759       } else {
760         ierr = PetscObjectReference((PetscObject)ts->Arhs);CHKERRQ(ierr);
761         ts->Brhs = ts->Arhs;
762       }
763     }
764     *Brhs = ts->Brhs;
765   }
766   PetscFunctionReturn(0);
767 }
768 
769 #undef __FUNCT__
770 #define __FUNCT__ "TSComputeIFunction"
771 /*@
772    TSComputeIFunction - Evaluates the DAE residual written in implicit form F(t,U,Udot)=0
773 
774    Collective on TS and Vec
775 
776    Input Parameters:
777 +  ts - the TS context
778 .  t - current time
779 .  U - state vector
780 .  Udot - time derivative of state vector
781 -  imex - flag indicates if the method is IMEX so that the RHSFunction should be kept separate
782 
783    Output Parameter:
784 .  Y - right hand side
785 
786    Note:
787    Most users should not need to explicitly call this routine, as it
788    is used internally within the nonlinear solvers.
789 
790    If the user did did not write their equations in implicit form, this
791    function recasts them in implicit form.
792 
793    Level: developer
794 
795 .keywords: TS, compute
796 
797 .seealso: TSSetIFunction(), TSComputeRHSFunction()
798 @*/
799 PetscErrorCode TSComputeIFunction(TS ts,PetscReal t,Vec U,Vec Udot,Vec Y,PetscBool imex)
800 {
801   PetscErrorCode ierr;
802   TSIFunction    ifunction;
803   TSRHSFunction  rhsfunction;
804   void           *ctx;
805   DM             dm;
806 
807   PetscFunctionBegin;
808   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
809   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
810   PetscValidHeaderSpecific(Udot,VEC_CLASSID,4);
811   PetscValidHeaderSpecific(Y,VEC_CLASSID,5);
812 
813   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
814   ierr = DMTSGetIFunction(dm,&ifunction,&ctx);CHKERRQ(ierr);
815   ierr = DMTSGetRHSFunction(dm,&rhsfunction,NULL);CHKERRQ(ierr);
816 
817   if (!rhsfunction && !ifunction) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSFunction() and / or TSSetIFunction()");
818 
819   ierr = PetscLogEventBegin(TS_FunctionEval,ts,U,Udot,Y);CHKERRQ(ierr);
820   if (ifunction) {
821     PetscStackPush("TS user implicit function");
822     ierr = (*ifunction)(ts,t,U,Udot,Y,ctx);CHKERRQ(ierr);
823     PetscStackPop;
824   }
825   if (imex) {
826     if (!ifunction) {
827       ierr = VecCopy(Udot,Y);CHKERRQ(ierr);
828     }
829   } else if (rhsfunction) {
830     if (ifunction) {
831       Vec Frhs;
832       ierr = TSGetRHSVec_Private(ts,&Frhs);CHKERRQ(ierr);
833       ierr = TSComputeRHSFunction(ts,t,U,Frhs);CHKERRQ(ierr);
834       ierr = VecAXPY(Y,-1,Frhs);CHKERRQ(ierr);
835     } else {
836       ierr = TSComputeRHSFunction(ts,t,U,Y);CHKERRQ(ierr);
837       ierr = VecAYPX(Y,-1,Udot);CHKERRQ(ierr);
838     }
839   }
840   ierr = PetscLogEventEnd(TS_FunctionEval,ts,U,Udot,Y);CHKERRQ(ierr);
841   PetscFunctionReturn(0);
842 }
843 
844 #undef __FUNCT__
845 #define __FUNCT__ "TSComputeIJacobian"
846 /*@
847    TSComputeIJacobian - Evaluates the Jacobian of the DAE
848 
849    Collective on TS and Vec
850 
851    Input
852       Input Parameters:
853 +  ts - the TS context
854 .  t - current timestep
855 .  U - state vector
856 .  Udot - time derivative of state vector
857 .  shift - shift to apply, see note below
858 -  imex - flag indicates if the method is IMEX so that the RHSJacobian should be kept separate
859 
860    Output Parameters:
861 +  A - Jacobian matrix
862 .  B - optional preconditioning matrix
863 -  flag - flag indicating matrix structure
864 
865    Notes:
866    If F(t,U,Udot)=0 is the DAE, the required Jacobian is
867 
868    dF/dU + shift*dF/dUdot
869 
870    Most users should not need to explicitly call this routine, as it
871    is used internally within the nonlinear solvers.
872 
873    Level: developer
874 
875 .keywords: TS, compute, Jacobian, matrix
876 
877 .seealso:  TSSetIJacobian()
878 @*/
879 PetscErrorCode TSComputeIJacobian(TS ts,PetscReal t,Vec U,Vec Udot,PetscReal shift,Mat A,Mat B,PetscBool imex)
880 {
881   PetscErrorCode ierr;
882   TSIJacobian    ijacobian;
883   TSRHSJacobian  rhsjacobian;
884   DM             dm;
885   void           *ctx;
886 
887   PetscFunctionBegin;
888   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
889   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
890   PetscValidHeaderSpecific(Udot,VEC_CLASSID,4);
891   PetscValidPointer(A,6);
892   PetscValidHeaderSpecific(A,MAT_CLASSID,6);
893   PetscValidPointer(B,7);
894   PetscValidHeaderSpecific(B,MAT_CLASSID,7);
895 
896   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
897   ierr = DMTSGetIJacobian(dm,&ijacobian,&ctx);CHKERRQ(ierr);
898   ierr = DMTSGetRHSJacobian(dm,&rhsjacobian,NULL);CHKERRQ(ierr);
899 
900   if (!rhsjacobian && !ijacobian) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSJacobian() and / or TSSetIJacobian()");
901 
902   ierr = PetscLogEventBegin(TS_JacobianEval,ts,U,A,B);CHKERRQ(ierr);
903   if (ijacobian) {
904     PetscBool missing;
905     PetscStackPush("TS user implicit Jacobian");
906     ierr = (*ijacobian)(ts,t,U,Udot,shift,A,B,ctx);CHKERRQ(ierr);
907     PetscStackPop;
908     if (A) {
909       ierr = MatMissingDiagonal(A,&missing,NULL);CHKERRQ(ierr);
910       if (missing) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Amat passed to TSSetIJacobian() must have all diagonal entries set, if they are zero you must still set them with a zero value");
911     }
912     if (B && B != A) {
913       ierr = MatMissingDiagonal(B,&missing,NULL);CHKERRQ(ierr);
914       if (missing) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Bmat passed to TSSetIJacobian() must have all diagonal entries set, if they are zero you must still set them with a zero value");
915     }
916   }
917   if (imex) {
918     if (!ijacobian) {  /* system was written as Udot = G(t,U) */
919       ierr = MatZeroEntries(A);CHKERRQ(ierr);
920       ierr = MatShift(A,shift);CHKERRQ(ierr);
921       if (A != B) {
922         ierr = MatZeroEntries(B);CHKERRQ(ierr);
923         ierr = MatShift(B,shift);CHKERRQ(ierr);
924       }
925     }
926   } else {
927     Mat Arhs = NULL,Brhs = NULL;
928     if (rhsjacobian) {
929       ierr = TSGetRHSMats_Private(ts,&Arhs,&Brhs);CHKERRQ(ierr);
930       ierr = TSComputeRHSJacobian(ts,t,U,Arhs,Brhs);CHKERRQ(ierr);
931     }
932     if (Arhs == A) {           /* No IJacobian, so we only have the RHS matrix */
933       ts->rhsjacobian.scale = -1;
934       ts->rhsjacobian.shift = shift;
935       ierr = MatScale(A,-1);CHKERRQ(ierr);
936       ierr = MatShift(A,shift);CHKERRQ(ierr);
937       if (A != B) {
938         ierr = MatScale(B,-1);CHKERRQ(ierr);
939         ierr = MatShift(B,shift);CHKERRQ(ierr);
940       }
941     } else if (Arhs) {          /* Both IJacobian and RHSJacobian */
942       MatStructure axpy = DIFFERENT_NONZERO_PATTERN;
943       if (!ijacobian) {         /* No IJacobian provided, but we have a separate RHS matrix */
944         ierr = MatZeroEntries(A);CHKERRQ(ierr);
945         ierr = MatShift(A,shift);CHKERRQ(ierr);
946         if (A != B) {
947           ierr = MatZeroEntries(B);CHKERRQ(ierr);
948           ierr = MatShift(B,shift);CHKERRQ(ierr);
949         }
950       }
951       ierr = MatAXPY(A,-1,Arhs,axpy);CHKERRQ(ierr);
952       if (A != B) {
953         ierr = MatAXPY(B,-1,Brhs,axpy);CHKERRQ(ierr);
954       }
955     }
956   }
957   ierr = PetscLogEventEnd(TS_JacobianEval,ts,U,A,B);CHKERRQ(ierr);
958   PetscFunctionReturn(0);
959 }
960 
961 #undef __FUNCT__
962 #define __FUNCT__ "TSSetRHSFunction"
963 /*@C
964     TSSetRHSFunction - Sets the routine for evaluating the function,
965     where U_t = G(t,u).
966 
967     Logically Collective on TS
968 
969     Input Parameters:
970 +   ts - the TS context obtained from TSCreate()
971 .   r - vector to put the computed right hand side (or NULL to have it created)
972 .   f - routine for evaluating the right-hand-side function
973 -   ctx - [optional] user-defined context for private data for the
974           function evaluation routine (may be NULL)
975 
976     Calling sequence of func:
977 $     func (TS ts,PetscReal t,Vec u,Vec F,void *ctx);
978 
979 +   t - current timestep
980 .   u - input vector
981 .   F - function vector
982 -   ctx - [optional] user-defined function context
983 
984     Level: beginner
985 
986     Notes: You must call this function or TSSetIFunction() to define your ODE. You cannot use this function when solving a DAE.
987 
988 .keywords: TS, timestep, set, right-hand-side, function
989 
990 .seealso: TSSetRHSJacobian(), TSSetIJacobian(), TSSetIFunction()
991 @*/
992 PetscErrorCode  TSSetRHSFunction(TS ts,Vec r,PetscErrorCode (*f)(TS,PetscReal,Vec,Vec,void*),void *ctx)
993 {
994   PetscErrorCode ierr;
995   SNES           snes;
996   Vec            ralloc = NULL;
997   DM             dm;
998 
999   PetscFunctionBegin;
1000   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1001   if (r) PetscValidHeaderSpecific(r,VEC_CLASSID,2);
1002 
1003   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1004   ierr = DMTSSetRHSFunction(dm,f,ctx);CHKERRQ(ierr);
1005   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1006   if (!r && !ts->dm && ts->vec_sol) {
1007     ierr = VecDuplicate(ts->vec_sol,&ralloc);CHKERRQ(ierr);
1008     r = ralloc;
1009   }
1010   ierr = SNESSetFunction(snes,r,SNESTSFormFunction,ts);CHKERRQ(ierr);
1011   ierr = VecDestroy(&ralloc);CHKERRQ(ierr);
1012   PetscFunctionReturn(0);
1013 }
1014 
1015 #undef __FUNCT__
1016 #define __FUNCT__ "TSSetSolutionFunction"
1017 /*@C
1018     TSSetSolutionFunction - Provide a function that computes the solution of the ODE or DAE
1019 
1020     Logically Collective on TS
1021 
1022     Input Parameters:
1023 +   ts - the TS context obtained from TSCreate()
1024 .   f - routine for evaluating the solution
1025 -   ctx - [optional] user-defined context for private data for the
1026           function evaluation routine (may be NULL)
1027 
1028     Calling sequence of func:
1029 $     func (TS ts,PetscReal t,Vec u,void *ctx);
1030 
1031 +   t - current timestep
1032 .   u - output vector
1033 -   ctx - [optional] user-defined function context
1034 
1035     Notes:
1036     This routine is used for testing accuracy of time integration schemes when you already know the solution.
1037     If analytic solutions are not known for your system, consider using the Method of Manufactured Solutions to
1038     create closed-form solutions with non-physical forcing terms.
1039 
1040     For low-dimensional problems solved in serial, such as small discrete systems, TSMonitorLGError() can be used to monitor the error history.
1041 
1042     Level: beginner
1043 
1044 .keywords: TS, timestep, set, right-hand-side, function
1045 
1046 .seealso: TSSetRHSJacobian(), TSSetIJacobian(), TSComputeSolutionFunction(), TSSetForcingFunction()
1047 @*/
1048 PetscErrorCode  TSSetSolutionFunction(TS ts,PetscErrorCode (*f)(TS,PetscReal,Vec,void*),void *ctx)
1049 {
1050   PetscErrorCode ierr;
1051   DM             dm;
1052 
1053   PetscFunctionBegin;
1054   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1055   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1056   ierr = DMTSSetSolutionFunction(dm,f,ctx);CHKERRQ(ierr);
1057   PetscFunctionReturn(0);
1058 }
1059 
1060 #undef __FUNCT__
1061 #define __FUNCT__ "TSSetForcingFunction"
1062 /*@C
1063     TSSetForcingFunction - Provide a function that computes a forcing term for a ODE or PDE
1064 
1065     Logically Collective on TS
1066 
1067     Input Parameters:
1068 +   ts - the TS context obtained from TSCreate()
1069 .   f - routine for evaluating the forcing function
1070 -   ctx - [optional] user-defined context for private data for the
1071           function evaluation routine (may be NULL)
1072 
1073     Calling sequence of func:
1074 $     func (TS ts,PetscReal t,Vec u,void *ctx);
1075 
1076 +   t - current timestep
1077 .   u - output vector
1078 -   ctx - [optional] user-defined function context
1079 
1080     Notes:
1081     This routine is useful for testing accuracy of time integration schemes when using the Method of Manufactured Solutions to
1082     create closed-form solutions with a non-physical forcing term.
1083 
1084     For low-dimensional problems solved in serial, such as small discrete systems, TSMonitorLGError() can be used to monitor the error history.
1085 
1086     Level: beginner
1087 
1088 .keywords: TS, timestep, set, right-hand-side, function
1089 
1090 .seealso: TSSetRHSJacobian(), TSSetIJacobian(), TSComputeSolutionFunction(), TSSetSolutionFunction()
1091 @*/
1092 PetscErrorCode  TSSetForcingFunction(TS ts,TSForcingFunction f,void *ctx)
1093 {
1094   PetscErrorCode ierr;
1095   DM             dm;
1096 
1097   PetscFunctionBegin;
1098   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1099   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1100   ierr = DMTSSetForcingFunction(dm,f,ctx);CHKERRQ(ierr);
1101   PetscFunctionReturn(0);
1102 }
1103 
1104 #undef __FUNCT__
1105 #define __FUNCT__ "TSSetRHSJacobian"
1106 /*@C
1107    TSSetRHSJacobian - Sets the function to compute the Jacobian of G,
1108    where U_t = G(U,t), as well as the location to store the matrix.
1109 
1110    Logically Collective on TS
1111 
1112    Input Parameters:
1113 +  ts  - the TS context obtained from TSCreate()
1114 .  Amat - (approximate) Jacobian matrix
1115 .  Pmat - matrix from which preconditioner is to be constructed (usually the same as Amat)
1116 .  f   - the Jacobian evaluation routine
1117 -  ctx - [optional] user-defined context for private data for the
1118          Jacobian evaluation routine (may be NULL)
1119 
1120    Calling sequence of f:
1121 $     func (TS ts,PetscReal t,Vec u,Mat A,Mat B,void *ctx);
1122 
1123 +  t - current timestep
1124 .  u - input vector
1125 .  Amat - (approximate) Jacobian matrix
1126 .  Pmat - matrix from which preconditioner is to be constructed (usually the same as Amat)
1127 -  ctx - [optional] user-defined context for matrix evaluation routine
1128 
1129    Notes:
1130    You must set all the diagonal entries of the matrices, if they are zero you must still set them with a zero value
1131 
1132    The TS solver may modify the nonzero structure and the entries of the matrices Amat and Pmat between the calls to f()
1133    You should not assume the values are the same in the next call to f() as you set them in the previous call.
1134 
1135    Level: beginner
1136 
1137 .keywords: TS, timestep, set, right-hand-side, Jacobian
1138 
1139 .seealso: SNESComputeJacobianDefaultColor(), TSSetRHSFunction(), TSRHSJacobianSetReuse(), TSSetIJacobian()
1140 
1141 @*/
1142 PetscErrorCode  TSSetRHSJacobian(TS ts,Mat Amat,Mat Pmat,TSRHSJacobian f,void *ctx)
1143 {
1144   PetscErrorCode ierr;
1145   SNES           snes;
1146   DM             dm;
1147   TSIJacobian    ijacobian;
1148 
1149   PetscFunctionBegin;
1150   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1151   if (Amat) PetscValidHeaderSpecific(Amat,MAT_CLASSID,2);
1152   if (Pmat) PetscValidHeaderSpecific(Pmat,MAT_CLASSID,3);
1153   if (Amat) PetscCheckSameComm(ts,1,Amat,2);
1154   if (Pmat) PetscCheckSameComm(ts,1,Pmat,3);
1155 
1156   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1157   ierr = DMTSSetRHSJacobian(dm,f,ctx);CHKERRQ(ierr);
1158   if (f == TSComputeRHSJacobianConstant) {
1159     /* Handle this case automatically for the user; otherwise user should call themselves. */
1160     ierr = TSRHSJacobianSetReuse(ts,PETSC_TRUE);CHKERRQ(ierr);
1161   }
1162   ierr = DMTSGetIJacobian(dm,&ijacobian,NULL);CHKERRQ(ierr);
1163   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1164   if (!ijacobian) {
1165     ierr = SNESSetJacobian(snes,Amat,Pmat,SNESTSFormJacobian,ts);CHKERRQ(ierr);
1166   }
1167   if (Amat) {
1168     ierr = PetscObjectReference((PetscObject)Amat);CHKERRQ(ierr);
1169     ierr = MatDestroy(&ts->Arhs);CHKERRQ(ierr);
1170     ts->Arhs = Amat;
1171   }
1172   if (Pmat) {
1173     ierr = PetscObjectReference((PetscObject)Pmat);CHKERRQ(ierr);
1174     ierr = MatDestroy(&ts->Brhs);CHKERRQ(ierr);
1175     ts->Brhs = Pmat;
1176   }
1177   PetscFunctionReturn(0);
1178 }
1179 
1180 
1181 #undef __FUNCT__
1182 #define __FUNCT__ "TSSetIFunction"
1183 /*@C
1184    TSSetIFunction - Set the function to compute F(t,U,U_t) where F() = 0 is the DAE to be solved.
1185 
1186    Logically Collective on TS
1187 
1188    Input Parameters:
1189 +  ts  - the TS context obtained from TSCreate()
1190 .  r   - vector to hold the residual (or NULL to have it created internally)
1191 .  f   - the function evaluation routine
1192 -  ctx - user-defined context for private data for the function evaluation routine (may be NULL)
1193 
1194    Calling sequence of f:
1195 $  f(TS ts,PetscReal t,Vec u,Vec u_t,Vec F,ctx);
1196 
1197 +  t   - time at step/stage being solved
1198 .  u   - state vector
1199 .  u_t - time derivative of state vector
1200 .  F   - function vector
1201 -  ctx - [optional] user-defined context for matrix evaluation routine
1202 
1203    Important:
1204    The user MUST call either this routine or TSSetRHSFunction() to define the ODE.  When solving DAEs you must use this function.
1205 
1206    Level: beginner
1207 
1208 .keywords: TS, timestep, set, DAE, Jacobian
1209 
1210 .seealso: TSSetRHSJacobian(), TSSetRHSFunction(), TSSetIJacobian()
1211 @*/
1212 PetscErrorCode  TSSetIFunction(TS ts,Vec r,TSIFunction f,void *ctx)
1213 {
1214   PetscErrorCode ierr;
1215   SNES           snes;
1216   Vec            ralloc = NULL;
1217   DM             dm;
1218 
1219   PetscFunctionBegin;
1220   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1221   if (r) PetscValidHeaderSpecific(r,VEC_CLASSID,2);
1222 
1223   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1224   ierr = DMTSSetIFunction(dm,f,ctx);CHKERRQ(ierr);
1225 
1226   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1227   if (!r && !ts->dm && ts->vec_sol) {
1228     ierr = VecDuplicate(ts->vec_sol,&ralloc);CHKERRQ(ierr);
1229     r  = ralloc;
1230   }
1231   ierr = SNESSetFunction(snes,r,SNESTSFormFunction,ts);CHKERRQ(ierr);
1232   ierr = VecDestroy(&ralloc);CHKERRQ(ierr);
1233   PetscFunctionReturn(0);
1234 }
1235 
1236 #undef __FUNCT__
1237 #define __FUNCT__ "TSGetIFunction"
1238 /*@C
1239    TSGetIFunction - Returns the vector where the implicit residual is stored and the function/contex to compute it.
1240 
1241    Not Collective
1242 
1243    Input Parameter:
1244 .  ts - the TS context
1245 
1246    Output Parameter:
1247 +  r - vector to hold residual (or NULL)
1248 .  func - the function to compute residual (or NULL)
1249 -  ctx - the function context (or NULL)
1250 
1251    Level: advanced
1252 
1253 .keywords: TS, nonlinear, get, function
1254 
1255 .seealso: TSSetIFunction(), SNESGetFunction()
1256 @*/
1257 PetscErrorCode TSGetIFunction(TS ts,Vec *r,TSIFunction *func,void **ctx)
1258 {
1259   PetscErrorCode ierr;
1260   SNES           snes;
1261   DM             dm;
1262 
1263   PetscFunctionBegin;
1264   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1265   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1266   ierr = SNESGetFunction(snes,r,NULL,NULL);CHKERRQ(ierr);
1267   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1268   ierr = DMTSGetIFunction(dm,func,ctx);CHKERRQ(ierr);
1269   PetscFunctionReturn(0);
1270 }
1271 
1272 #undef __FUNCT__
1273 #define __FUNCT__ "TSGetRHSFunction"
1274 /*@C
1275    TSGetRHSFunction - Returns the vector where the right hand side is stored and the function/context to compute it.
1276 
1277    Not Collective
1278 
1279    Input Parameter:
1280 .  ts - the TS context
1281 
1282    Output Parameter:
1283 +  r - vector to hold computed right hand side (or NULL)
1284 .  func - the function to compute right hand side (or NULL)
1285 -  ctx - the function context (or NULL)
1286 
1287    Level: advanced
1288 
1289 .keywords: TS, nonlinear, get, function
1290 
1291 .seealso: TSSetRHSFunction(), SNESGetFunction()
1292 @*/
1293 PetscErrorCode TSGetRHSFunction(TS ts,Vec *r,TSRHSFunction *func,void **ctx)
1294 {
1295   PetscErrorCode ierr;
1296   SNES           snes;
1297   DM             dm;
1298 
1299   PetscFunctionBegin;
1300   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1301   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1302   ierr = SNESGetFunction(snes,r,NULL,NULL);CHKERRQ(ierr);
1303   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1304   ierr = DMTSGetRHSFunction(dm,func,ctx);CHKERRQ(ierr);
1305   PetscFunctionReturn(0);
1306 }
1307 
1308 #undef __FUNCT__
1309 #define __FUNCT__ "TSSetIJacobian"
1310 /*@C
1311    TSSetIJacobian - Set the function to compute the matrix dF/dU + a*dF/dU_t where F(t,U,U_t) is the function
1312         provided with TSSetIFunction().
1313 
1314    Logically Collective on TS
1315 
1316    Input Parameters:
1317 +  ts  - the TS context obtained from TSCreate()
1318 .  Amat - (approximate) Jacobian matrix
1319 .  Pmat - matrix used to compute preconditioner (usually the same as Amat)
1320 .  f   - the Jacobian evaluation routine
1321 -  ctx - user-defined context for private data for the Jacobian evaluation routine (may be NULL)
1322 
1323    Calling sequence of f:
1324 $  f(TS ts,PetscReal t,Vec U,Vec U_t,PetscReal a,Mat Amat,Mat Pmat,void *ctx);
1325 
1326 +  t    - time at step/stage being solved
1327 .  U    - state vector
1328 .  U_t  - time derivative of state vector
1329 .  a    - shift
1330 .  Amat - (approximate) Jacobian of F(t,U,W+a*U), equivalent to dF/dU + a*dF/dU_t
1331 .  Pmat - matrix used for constructing preconditioner, usually the same as Amat
1332 -  ctx  - [optional] user-defined context for matrix evaluation routine
1333 
1334    Notes:
1335    The matrices Amat and Pmat are exactly the matrices that are used by SNES for the nonlinear solve.
1336 
1337    If you know the operator Amat has a null space you can use MatSetNullSpace() and MatSetTransposeNullSpace() to supply the null
1338    space to Amat and the KSP solvers will automatically use that null space as needed during the solution process.
1339 
1340    The matrix dF/dU + a*dF/dU_t you provide turns out to be
1341    the Jacobian of F(t,U,W+a*U) where F(t,U,U_t) = 0 is the DAE to be solved.
1342    The time integrator internally approximates U_t by W+a*U where the positive "shift"
1343    a and vector W depend on the integration method, step size, and past states. For example with
1344    the backward Euler method a = 1/dt and W = -a*U(previous timestep) so
1345    W + a*U = a*(U - U(previous timestep)) = (U - U(previous timestep))/dt
1346 
1347    You must set all the diagonal entries of the matrices, if they are zero you must still set them with a zero value
1348 
1349    The TS solver may modify the nonzero structure and the entries of the matrices Amat and Pmat between the calls to f()
1350    You should not assume the values are the same in the next call to f() as you set them in the previous call.
1351 
1352    Level: beginner
1353 
1354 .keywords: TS, timestep, DAE, Jacobian
1355 
1356 .seealso: TSSetIFunction(), TSSetRHSJacobian(), SNESComputeJacobianDefaultColor(), SNESComputeJacobianDefault(), TSSetRHSFunction()
1357 
1358 @*/
1359 PetscErrorCode  TSSetIJacobian(TS ts,Mat Amat,Mat Pmat,TSIJacobian f,void *ctx)
1360 {
1361   PetscErrorCode ierr;
1362   SNES           snes;
1363   DM             dm;
1364 
1365   PetscFunctionBegin;
1366   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1367   if (Amat) PetscValidHeaderSpecific(Amat,MAT_CLASSID,2);
1368   if (Pmat) PetscValidHeaderSpecific(Pmat,MAT_CLASSID,3);
1369   if (Amat) PetscCheckSameComm(ts,1,Amat,2);
1370   if (Pmat) PetscCheckSameComm(ts,1,Pmat,3);
1371 
1372   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1373   ierr = DMTSSetIJacobian(dm,f,ctx);CHKERRQ(ierr);
1374 
1375   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1376   ierr = SNESSetJacobian(snes,Amat,Pmat,SNESTSFormJacobian,ts);CHKERRQ(ierr);
1377   PetscFunctionReturn(0);
1378 }
1379 
1380 #undef __FUNCT__
1381 #define __FUNCT__ "TSRHSJacobianSetReuse"
1382 /*@
1383    TSRHSJacobianSetReuse - restore RHS Jacobian before re-evaluating.  Without this flag, TS will change the sign and
1384    shift the RHS Jacobian for a finite-time-step implicit solve, in which case the user function will need to recompute
1385    the entire Jacobian.  The reuse flag must be set if the evaluation function will assume that the matrix entries have
1386    not been changed by the TS.
1387 
1388    Logically Collective
1389 
1390    Input Arguments:
1391 +  ts - TS context obtained from TSCreate()
1392 -  reuse - PETSC_TRUE if the RHS Jacobian
1393 
1394    Level: intermediate
1395 
1396 .seealso: TSSetRHSJacobian(), TSComputeRHSJacobianConstant()
1397 @*/
1398 PetscErrorCode TSRHSJacobianSetReuse(TS ts,PetscBool reuse)
1399 {
1400   PetscFunctionBegin;
1401   ts->rhsjacobian.reuse = reuse;
1402   PetscFunctionReturn(0);
1403 }
1404 
1405 #undef __FUNCT__
1406 #define __FUNCT__ "TSSetI2Function"
1407 /*@C
1408    TSSetI2Function - Set the function to compute F(t,U,U_t,U_tt) where F = 0 is the DAE to be solved.
1409 
1410    Logically Collective on TS
1411 
1412    Input Parameters:
1413 +  ts  - the TS context obtained from TSCreate()
1414 .  F   - vector to hold the residual (or NULL to have it created internally)
1415 .  fun - the function evaluation routine
1416 -  ctx - user-defined context for private data for the function evaluation routine (may be NULL)
1417 
1418    Calling sequence of fun:
1419 $  fun(TS ts,PetscReal t,Vec U,Vec U_t,Vec U_tt,Vec F,ctx);
1420 
1421 +  t    - time at step/stage being solved
1422 .  U    - state vector
1423 .  U_t  - time derivative of state vector
1424 .  U_tt - second time derivative of state vector
1425 .  F    - function vector
1426 -  ctx  - [optional] user-defined context for matrix evaluation routine (may be NULL)
1427 
1428    Level: beginner
1429 
1430 .keywords: TS, timestep, set, ODE, DAE, Function
1431 
1432 .seealso: TSSetI2Jacobian()
1433 @*/
1434 PetscErrorCode TSSetI2Function(TS ts,Vec F,TSI2Function fun,void *ctx)
1435 {
1436   DM             dm;
1437   PetscErrorCode ierr;
1438 
1439   PetscFunctionBegin;
1440   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1441   if (F) PetscValidHeaderSpecific(F,VEC_CLASSID,2);
1442   ierr = TSSetIFunction(ts,F,NULL,NULL);CHKERRQ(ierr);
1443   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1444   ierr = DMTSSetI2Function(dm,fun,ctx);CHKERRQ(ierr);
1445   PetscFunctionReturn(0);
1446 }
1447 
1448 #undef __FUNCT__
1449 #define __FUNCT__ "TSGetI2Function"
1450 /*@C
1451   TSGetI2Function - Returns the vector where the implicit residual is stored and the function/contex to compute it.
1452 
1453   Not Collective
1454 
1455   Input Parameter:
1456 . ts - the TS context
1457 
1458   Output Parameter:
1459 + r - vector to hold residual (or NULL)
1460 . fun - the function to compute residual (or NULL)
1461 - ctx - the function context (or NULL)
1462 
1463   Level: advanced
1464 
1465 .keywords: TS, nonlinear, get, function
1466 
1467 .seealso: TSSetI2Function(), SNESGetFunction()
1468 @*/
1469 PetscErrorCode TSGetI2Function(TS ts,Vec *r,TSI2Function *fun,void **ctx)
1470 {
1471   PetscErrorCode ierr;
1472   SNES           snes;
1473   DM             dm;
1474 
1475   PetscFunctionBegin;
1476   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1477   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1478   ierr = SNESGetFunction(snes,r,NULL,NULL);CHKERRQ(ierr);
1479   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1480   ierr = DMTSGetI2Function(dm,fun,ctx);CHKERRQ(ierr);
1481   PetscFunctionReturn(0);
1482 }
1483 
1484 #undef __FUNCT__
1485 #define __FUNCT__ "TSSetI2Jacobian"
1486 /*@C
1487    TSSetI2Jacobian - Set the function to compute the matrix dF/dU + v*dF/dU_t  + a*dF/dU_tt
1488         where F(t,U,U_t,U_tt) is the function you provided with TSSetI2Function().
1489 
1490    Logically Collective on TS
1491 
1492    Input Parameters:
1493 +  ts  - the TS context obtained from TSCreate()
1494 .  J   - Jacobian matrix
1495 .  P   - preconditioning matrix for J (may be same as J)
1496 .  jac - the Jacobian evaluation routine
1497 -  ctx - user-defined context for private data for the Jacobian evaluation routine (may be NULL)
1498 
1499    Calling sequence of jac:
1500 $  jac(TS ts,PetscReal t,Vec U,Vec U_t,Vec U_tt,PetscReal v,PetscReal a,Mat J,Mat P,void *ctx);
1501 
1502 +  t    - time at step/stage being solved
1503 .  U    - state vector
1504 .  U_t  - time derivative of state vector
1505 .  U_tt - second time derivative of state vector
1506 .  v    - shift for U_t
1507 .  a    - shift for U_tt
1508 .  J    - Jacobian of G(U) = F(t,U,W+v*U,W'+a*U), equivalent to dF/dU + v*dF/dU_t  + a*dF/dU_tt
1509 .  P    - preconditioning matrix for J, may be same as J
1510 -  ctx  - [optional] user-defined context for matrix evaluation routine
1511 
1512    Notes:
1513    The matrices J and P are exactly the matrices that are used by SNES for the nonlinear solve.
1514 
1515    The matrix dF/dU + v*dF/dU_t + a*dF/dU_tt you provide turns out to be
1516    the Jacobian of G(U) = F(t,U,W+v*U,W'+a*U) where F(t,U,U_t,U_tt) = 0 is the DAE to be solved.
1517    The time integrator internally approximates U_t by W+v*U and U_tt by W'+a*U  where the positive "shift"
1518    parameters 'v' and 'a' and vectors W, W' depend on the integration method, step size, and past states.
1519 
1520    Level: beginner
1521 
1522 .keywords: TS, timestep, set, ODE, DAE, Jacobian
1523 
1524 .seealso: TSSetI2Function()
1525 @*/
1526 PetscErrorCode TSSetI2Jacobian(TS ts,Mat J,Mat P,TSI2Jacobian jac,void *ctx)
1527 {
1528   DM             dm;
1529   PetscErrorCode ierr;
1530 
1531   PetscFunctionBegin;
1532   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1533   if (J) PetscValidHeaderSpecific(J,MAT_CLASSID,2);
1534   if (P) PetscValidHeaderSpecific(P,MAT_CLASSID,3);
1535   ierr = TSSetIJacobian(ts,J,P,NULL,NULL);CHKERRQ(ierr);
1536   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1537   ierr = DMTSSetI2Jacobian(dm,jac,ctx);CHKERRQ(ierr);
1538   PetscFunctionReturn(0);
1539 }
1540 
1541 #undef __FUNCT__
1542 #define __FUNCT__ "TSGetI2Jacobian"
1543 /*@C
1544   TSGetI2Jacobian - Returns the implicit Jacobian at the present timestep.
1545 
1546   Not Collective, but parallel objects are returned if TS is parallel
1547 
1548   Input Parameter:
1549 . ts  - The TS context obtained from TSCreate()
1550 
1551   Output Parameters:
1552 + J  - The (approximate) Jacobian of F(t,U,U_t,U_tt)
1553 . P - The matrix from which the preconditioner is constructed, often the same as J
1554 . jac - The function to compute the Jacobian matrices
1555 - ctx - User-defined context for Jacobian evaluation routine
1556 
1557   Notes: You can pass in NULL for any return argument you do not need.
1558 
1559   Level: advanced
1560 
1561 .seealso: TSGetTimeStep(), TSGetMatrices(), TSGetTime(), TSGetTimeStepNumber()
1562 
1563 .keywords: TS, timestep, get, matrix, Jacobian
1564 @*/
1565 PetscErrorCode  TSGetI2Jacobian(TS ts,Mat *J,Mat *P,TSI2Jacobian *jac,void **ctx)
1566 {
1567   PetscErrorCode ierr;
1568   SNES           snes;
1569   DM             dm;
1570 
1571   PetscFunctionBegin;
1572   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1573   ierr = SNESSetUpMatrices(snes);CHKERRQ(ierr);
1574   ierr = SNESGetJacobian(snes,J,P,NULL,NULL);CHKERRQ(ierr);
1575   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1576   ierr = DMTSGetI2Jacobian(dm,jac,ctx);CHKERRQ(ierr);
1577   PetscFunctionReturn(0);
1578 }
1579 
1580 #undef __FUNCT__
1581 #define __FUNCT__ "TSComputeI2Function"
1582 /*@
1583   TSComputeI2Function - Evaluates the DAE residual written in implicit form F(t,U,U_t,U_tt) = 0
1584 
1585   Collective on TS and Vec
1586 
1587   Input Parameters:
1588 + ts - the TS context
1589 . t - current time
1590 . U - state vector
1591 . V - time derivative of state vector (U_t)
1592 - A - second time derivative of state vector (U_tt)
1593 
1594   Output Parameter:
1595 . F - the residual vector
1596 
1597   Note:
1598   Most users should not need to explicitly call this routine, as it
1599   is used internally within the nonlinear solvers.
1600 
1601   Level: developer
1602 
1603 .keywords: TS, compute, function, vector
1604 
1605 .seealso: TSSetI2Function()
1606 @*/
1607 PetscErrorCode TSComputeI2Function(TS ts,PetscReal t,Vec U,Vec V,Vec A,Vec F)
1608 {
1609   DM             dm;
1610   TSI2Function   I2Function;
1611   void           *ctx;
1612   TSRHSFunction  rhsfunction;
1613   PetscErrorCode ierr;
1614 
1615   PetscFunctionBegin;
1616   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1617   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
1618   PetscValidHeaderSpecific(V,VEC_CLASSID,4);
1619   PetscValidHeaderSpecific(A,VEC_CLASSID,5);
1620   PetscValidHeaderSpecific(F,VEC_CLASSID,6);
1621 
1622   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1623   ierr = DMTSGetI2Function(dm,&I2Function,&ctx);CHKERRQ(ierr);
1624   ierr = DMTSGetRHSFunction(dm,&rhsfunction,NULL);CHKERRQ(ierr);
1625 
1626   if (!I2Function) {
1627     ierr = TSComputeIFunction(ts,t,U,A,F,PETSC_FALSE);CHKERRQ(ierr);
1628     PetscFunctionReturn(0);
1629   }
1630 
1631   ierr = PetscLogEventBegin(TS_FunctionEval,ts,U,V,F);CHKERRQ(ierr);
1632 
1633   PetscStackPush("TS user implicit function");
1634   ierr = I2Function(ts,t,U,V,A,F,ctx);CHKERRQ(ierr);
1635   PetscStackPop;
1636 
1637   if (rhsfunction) {
1638     Vec Frhs;
1639     ierr = TSGetRHSVec_Private(ts,&Frhs);CHKERRQ(ierr);
1640     ierr = TSComputeRHSFunction(ts,t,U,Frhs);CHKERRQ(ierr);
1641     ierr = VecAXPY(F,-1,Frhs);CHKERRQ(ierr);
1642   }
1643 
1644   ierr = PetscLogEventEnd(TS_FunctionEval,ts,U,V,F);CHKERRQ(ierr);
1645   PetscFunctionReturn(0);
1646 }
1647 
1648 #undef __FUNCT__
1649 #define __FUNCT__ "TSComputeI2Jacobian"
1650 /*@
1651   TSComputeI2Jacobian - Evaluates the Jacobian of the DAE
1652 
1653   Collective on TS and Vec
1654 
1655   Input Parameters:
1656 + ts - the TS context
1657 . t - current timestep
1658 . U - state vector
1659 . V - time derivative of state vector
1660 . A - second time derivative of state vector
1661 . shiftV - shift to apply, see note below
1662 - shiftA - shift to apply, see note below
1663 
1664   Output Parameters:
1665 + J - Jacobian matrix
1666 - P - optional preconditioning matrix
1667 
1668   Notes:
1669   If F(t,U,V,A)=0 is the DAE, the required Jacobian is
1670 
1671   dF/dU + shiftV*dF/dV + shiftA*dF/dA
1672 
1673   Most users should not need to explicitly call this routine, as it
1674   is used internally within the nonlinear solvers.
1675 
1676   Level: developer
1677 
1678 .keywords: TS, compute, Jacobian, matrix
1679 
1680 .seealso:  TSSetI2Jacobian()
1681 @*/
1682 PetscErrorCode TSComputeI2Jacobian(TS ts,PetscReal t,Vec U,Vec V,Vec A,PetscReal shiftV,PetscReal shiftA,Mat J,Mat P)
1683 {
1684   DM             dm;
1685   TSI2Jacobian   I2Jacobian;
1686   void           *ctx;
1687   TSRHSJacobian  rhsjacobian;
1688   PetscErrorCode ierr;
1689 
1690   PetscFunctionBegin;
1691   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1692   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
1693   PetscValidHeaderSpecific(V,VEC_CLASSID,4);
1694   PetscValidHeaderSpecific(A,VEC_CLASSID,5);
1695   PetscValidHeaderSpecific(J,MAT_CLASSID,8);
1696   PetscValidHeaderSpecific(P,MAT_CLASSID,9);
1697 
1698   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1699   ierr = DMTSGetI2Jacobian(dm,&I2Jacobian,&ctx);CHKERRQ(ierr);
1700   ierr = DMTSGetRHSJacobian(dm,&rhsjacobian,NULL);CHKERRQ(ierr);
1701 
1702   if (!I2Jacobian) {
1703     ierr = TSComputeIJacobian(ts,t,U,A,shiftA,J,P,PETSC_FALSE);CHKERRQ(ierr);
1704     PetscFunctionReturn(0);
1705   }
1706 
1707   ierr = PetscLogEventBegin(TS_JacobianEval,ts,U,J,P);CHKERRQ(ierr);
1708 
1709   PetscStackPush("TS user implicit Jacobian");
1710   ierr = I2Jacobian(ts,t,U,V,A,shiftV,shiftA,J,P,ctx);CHKERRQ(ierr);
1711   PetscStackPop;
1712 
1713   if (rhsjacobian) {
1714     Mat Jrhs,Prhs; MatStructure axpy = DIFFERENT_NONZERO_PATTERN;
1715     ierr = TSGetRHSMats_Private(ts,&Jrhs,&Prhs);CHKERRQ(ierr);
1716     ierr = TSComputeRHSJacobian(ts,t,U,Jrhs,Prhs);CHKERRQ(ierr);
1717     ierr = MatAXPY(J,-1,Jrhs,axpy);CHKERRQ(ierr);
1718     if (P != J) {ierr = MatAXPY(P,-1,Prhs,axpy);CHKERRQ(ierr);}
1719   }
1720 
1721   ierr = PetscLogEventEnd(TS_JacobianEval,ts,U,J,P);CHKERRQ(ierr);
1722   PetscFunctionReturn(0);
1723 }
1724 
1725 #undef __FUNCT__
1726 #define __FUNCT__ "TS2SetSolution"
1727 /*@
1728    TS2SetSolution - Sets the initial solution and time derivative vectors
1729    for use by the TS routines handling second order equations.
1730 
1731    Logically Collective on TS and Vec
1732 
1733    Input Parameters:
1734 +  ts - the TS context obtained from TSCreate()
1735 .  u - the solution vector
1736 -  v - the time derivative vector
1737 
1738    Level: beginner
1739 
1740 .keywords: TS, timestep, set, solution, initial conditions
1741 @*/
1742 PetscErrorCode  TS2SetSolution(TS ts,Vec u,Vec v)
1743 {
1744   PetscErrorCode ierr;
1745 
1746   PetscFunctionBegin;
1747   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1748   PetscValidHeaderSpecific(u,VEC_CLASSID,2);
1749   PetscValidHeaderSpecific(v,VEC_CLASSID,3);
1750   ierr = TSSetSolution(ts,u);CHKERRQ(ierr);
1751   ierr = PetscObjectReference((PetscObject)v);CHKERRQ(ierr);
1752   ierr = VecDestroy(&ts->vec_dot);CHKERRQ(ierr);
1753   ts->vec_dot = v;
1754   PetscFunctionReturn(0);
1755 }
1756 
1757 #undef __FUNCT__
1758 #define __FUNCT__ "TS2GetSolution"
1759 /*@
1760    TS2GetSolution - Returns the solution and time derivative at the present timestep
1761    for second order equations. It is valid to call this routine inside the function
1762    that you are evaluating in order to move to the new timestep. This vector not
1763    changed until the solution at the next timestep has been calculated.
1764 
1765    Not Collective, but Vec returned is parallel if TS is parallel
1766 
1767    Input Parameter:
1768 .  ts - the TS context obtained from TSCreate()
1769 
1770    Output Parameter:
1771 +  u - the vector containing the solution
1772 -  v - the vector containing the time derivative
1773 
1774    Level: intermediate
1775 
1776 .seealso: TS2SetSolution(), TSGetTimeStep(), TSGetTime()
1777 
1778 .keywords: TS, timestep, get, solution
1779 @*/
1780 PetscErrorCode  TS2GetSolution(TS ts,Vec *u,Vec *v)
1781 {
1782   PetscFunctionBegin;
1783   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1784   if (u) PetscValidPointer(u,2);
1785   if (v) PetscValidPointer(v,3);
1786   if (u) *u = ts->vec_sol;
1787   if (v) *v = ts->vec_dot;
1788   PetscFunctionReturn(0);
1789 }
1790 
1791 #undef __FUNCT__
1792 #define __FUNCT__ "TSLoad"
1793 /*@C
1794   TSLoad - Loads a KSP that has been stored in binary  with KSPView().
1795 
1796   Collective on PetscViewer
1797 
1798   Input Parameters:
1799 + newdm - the newly loaded TS, this needs to have been created with TSCreate() or
1800            some related function before a call to TSLoad().
1801 - viewer - binary file viewer, obtained from PetscViewerBinaryOpen()
1802 
1803    Level: intermediate
1804 
1805   Notes:
1806    The type is determined by the data in the file, any type set into the TS before this call is ignored.
1807 
1808   Notes for advanced users:
1809   Most users should not need to know the details of the binary storage
1810   format, since TSLoad() and TSView() completely hide these details.
1811   But for anyone who's interested, the standard binary matrix storage
1812   format is
1813 .vb
1814      has not yet been determined
1815 .ve
1816 
1817 .seealso: PetscViewerBinaryOpen(), TSView(), MatLoad(), VecLoad()
1818 @*/
1819 PetscErrorCode  TSLoad(TS ts, PetscViewer viewer)
1820 {
1821   PetscErrorCode ierr;
1822   PetscBool      isbinary;
1823   PetscInt       classid;
1824   char           type[256];
1825   DMTS           sdm;
1826   DM             dm;
1827 
1828   PetscFunctionBegin;
1829   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1830   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2);
1831   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1832   if (!isbinary) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid viewer; open viewer with PetscViewerBinaryOpen()");
1833 
1834   ierr = PetscViewerBinaryRead(viewer,&classid,1,NULL,PETSC_INT);CHKERRQ(ierr);
1835   if (classid != TS_FILE_CLASSID) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Not TS next in file");
1836   ierr = PetscViewerBinaryRead(viewer,type,256,NULL,PETSC_CHAR);CHKERRQ(ierr);
1837   ierr = TSSetType(ts, type);CHKERRQ(ierr);
1838   if (ts->ops->load) {
1839     ierr = (*ts->ops->load)(ts,viewer);CHKERRQ(ierr);
1840   }
1841   ierr = DMCreate(PetscObjectComm((PetscObject)ts),&dm);CHKERRQ(ierr);
1842   ierr = DMLoad(dm,viewer);CHKERRQ(ierr);
1843   ierr = TSSetDM(ts,dm);CHKERRQ(ierr);
1844   ierr = DMCreateGlobalVector(ts->dm,&ts->vec_sol);CHKERRQ(ierr);
1845   ierr = VecLoad(ts->vec_sol,viewer);CHKERRQ(ierr);
1846   ierr = DMGetDMTS(ts->dm,&sdm);CHKERRQ(ierr);
1847   ierr = DMTSLoad(sdm,viewer);CHKERRQ(ierr);
1848   PetscFunctionReturn(0);
1849 }
1850 
1851 #include <petscdraw.h>
1852 #if defined(PETSC_HAVE_SAWS)
1853 #include <petscviewersaws.h>
1854 #endif
1855 #undef __FUNCT__
1856 #define __FUNCT__ "TSView"
1857 /*@C
1858     TSView - Prints the TS data structure.
1859 
1860     Collective on TS
1861 
1862     Input Parameters:
1863 +   ts - the TS context obtained from TSCreate()
1864 -   viewer - visualization context
1865 
1866     Options Database Key:
1867 .   -ts_view - calls TSView() at end of TSStep()
1868 
1869     Notes:
1870     The available visualization contexts include
1871 +     PETSC_VIEWER_STDOUT_SELF - standard output (default)
1872 -     PETSC_VIEWER_STDOUT_WORLD - synchronized standard
1873          output where only the first processor opens
1874          the file.  All other processors send their
1875          data to the first processor to print.
1876 
1877     The user can open an alternative visualization context with
1878     PetscViewerASCIIOpen() - output to a specified file.
1879 
1880     Level: beginner
1881 
1882 .keywords: TS, timestep, view
1883 
1884 .seealso: PetscViewerASCIIOpen()
1885 @*/
1886 PetscErrorCode  TSView(TS ts,PetscViewer viewer)
1887 {
1888   PetscErrorCode ierr;
1889   TSType         type;
1890   PetscBool      iascii,isstring,isundials,isbinary,isdraw;
1891   DMTS           sdm;
1892 #if defined(PETSC_HAVE_SAWS)
1893   PetscBool      issaws;
1894 #endif
1895 
1896   PetscFunctionBegin;
1897   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1898   if (!viewer) {
1899     ierr = PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)ts),&viewer);CHKERRQ(ierr);
1900   }
1901   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2);
1902   PetscCheckSameComm(ts,1,viewer,2);
1903 
1904   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1905   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);CHKERRQ(ierr);
1906   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1907   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1908 #if defined(PETSC_HAVE_SAWS)
1909   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSAWS,&issaws);CHKERRQ(ierr);
1910 #endif
1911   if (iascii) {
1912     ierr = PetscObjectPrintClassNamePrefixType((PetscObject)ts,viewer);CHKERRQ(ierr);
1913     ierr = PetscViewerASCIIPrintf(viewer,"  maximum steps=%D\n",ts->max_steps);CHKERRQ(ierr);
1914     ierr = PetscViewerASCIIPrintf(viewer,"  maximum time=%g\n",(double)ts->max_time);CHKERRQ(ierr);
1915     if (ts->problem_type == TS_NONLINEAR) {
1916       ierr = PetscViewerASCIIPrintf(viewer,"  total number of nonlinear solver iterations=%D\n",ts->snes_its);CHKERRQ(ierr);
1917       ierr = PetscViewerASCIIPrintf(viewer,"  total number of nonlinear solve failures=%D\n",ts->num_snes_failures);CHKERRQ(ierr);
1918     }
1919     ierr = PetscViewerASCIIPrintf(viewer,"  total number of linear solver iterations=%D\n",ts->ksp_its);CHKERRQ(ierr);
1920     ierr = PetscViewerASCIIPrintf(viewer,"  total number of rejected steps=%D\n",ts->reject);CHKERRQ(ierr);
1921     if (ts->vrtol) {
1922       ierr = PetscViewerASCIIPrintf(viewer,"  using vector of relative error tolerances, ");CHKERRQ(ierr);
1923     } else {
1924       ierr = PetscViewerASCIIPrintf(viewer,"  using relative error tolerance of %g, ",(double)ts->rtol);CHKERRQ(ierr);
1925     }
1926     if (ts->vatol) {
1927       ierr = PetscViewerASCIIPrintf(viewer,"  using vector of absolute error tolerances\n");CHKERRQ(ierr);
1928     } else {
1929       ierr = PetscViewerASCIIPrintf(viewer,"  using absolute error tolerance of %g\n",(double)ts->atol);CHKERRQ(ierr);
1930     }
1931     ierr = DMGetDMTS(ts->dm,&sdm);CHKERRQ(ierr);
1932     ierr = DMTSView(sdm,viewer);CHKERRQ(ierr);
1933     if (ts->ops->view) {
1934       ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
1935       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
1936       ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
1937     }
1938   } else if (isstring) {
1939     ierr = TSGetType(ts,&type);CHKERRQ(ierr);
1940     ierr = PetscViewerStringSPrintf(viewer," %-7.7s",type);CHKERRQ(ierr);
1941   } else if (isbinary) {
1942     PetscInt    classid = TS_FILE_CLASSID;
1943     MPI_Comm    comm;
1944     PetscMPIInt rank;
1945     char        type[256];
1946 
1947     ierr = PetscObjectGetComm((PetscObject)ts,&comm);CHKERRQ(ierr);
1948     ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
1949     if (!rank) {
1950       ierr = PetscViewerBinaryWrite(viewer,&classid,1,PETSC_INT,PETSC_FALSE);CHKERRQ(ierr);
1951       ierr = PetscStrncpy(type,((PetscObject)ts)->type_name,256);CHKERRQ(ierr);
1952       ierr = PetscViewerBinaryWrite(viewer,type,256,PETSC_CHAR,PETSC_FALSE);CHKERRQ(ierr);
1953     }
1954     if (ts->ops->view) {
1955       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
1956     }
1957     ierr = DMView(ts->dm,viewer);CHKERRQ(ierr);
1958     ierr = VecView(ts->vec_sol,viewer);CHKERRQ(ierr);
1959     ierr = DMGetDMTS(ts->dm,&sdm);CHKERRQ(ierr);
1960     ierr = DMTSView(sdm,viewer);CHKERRQ(ierr);
1961   } else if (isdraw) {
1962     PetscDraw draw;
1963     char      str[36];
1964     PetscReal x,y,bottom,h;
1965 
1966     ierr   = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
1967     ierr   = PetscDrawGetCurrentPoint(draw,&x,&y);CHKERRQ(ierr);
1968     ierr   = PetscStrcpy(str,"TS: ");CHKERRQ(ierr);
1969     ierr   = PetscStrcat(str,((PetscObject)ts)->type_name);CHKERRQ(ierr);
1970     ierr   = PetscDrawStringBoxed(draw,x,y,PETSC_DRAW_BLACK,PETSC_DRAW_BLACK,str,NULL,&h);CHKERRQ(ierr);
1971     bottom = y - h;
1972     ierr   = PetscDrawPushCurrentPoint(draw,x,bottom);CHKERRQ(ierr);
1973     if (ts->ops->view) {
1974       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
1975     }
1976     ierr = PetscDrawPopCurrentPoint(draw);CHKERRQ(ierr);
1977 #if defined(PETSC_HAVE_SAWS)
1978   } else if (issaws) {
1979     PetscMPIInt rank;
1980     const char  *name;
1981 
1982     ierr = PetscObjectGetName((PetscObject)ts,&name);CHKERRQ(ierr);
1983     ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
1984     if (!((PetscObject)ts)->amsmem && !rank) {
1985       char       dir[1024];
1986 
1987       ierr = PetscObjectViewSAWs((PetscObject)ts,viewer);CHKERRQ(ierr);
1988       ierr = PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/time_step",name);CHKERRQ(ierr);
1989       PetscStackCallSAWs(SAWs_Register,(dir,&ts->steps,1,SAWs_READ,SAWs_INT));
1990       ierr = PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/time",name);CHKERRQ(ierr);
1991       PetscStackCallSAWs(SAWs_Register,(dir,&ts->ptime,1,SAWs_READ,SAWs_DOUBLE));
1992     }
1993     if (ts->ops->view) {
1994       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
1995     }
1996 #endif
1997   }
1998 
1999   ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
2000   ierr = PetscObjectTypeCompare((PetscObject)ts,TSSUNDIALS,&isundials);CHKERRQ(ierr);
2001   ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
2002   PetscFunctionReturn(0);
2003 }
2004 
2005 
2006 #undef __FUNCT__
2007 #define __FUNCT__ "TSSetApplicationContext"
2008 /*@
2009    TSSetApplicationContext - Sets an optional user-defined context for
2010    the timesteppers.
2011 
2012    Logically Collective on TS
2013 
2014    Input Parameters:
2015 +  ts - the TS context obtained from TSCreate()
2016 -  usrP - optional user context
2017 
2018    Fortran Notes: To use this from Fortran you must write a Fortran interface definition for this
2019     function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
2020 
2021    Level: intermediate
2022 
2023 .keywords: TS, timestep, set, application, context
2024 
2025 .seealso: TSGetApplicationContext()
2026 @*/
2027 PetscErrorCode  TSSetApplicationContext(TS ts,void *usrP)
2028 {
2029   PetscFunctionBegin;
2030   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2031   ts->user = usrP;
2032   PetscFunctionReturn(0);
2033 }
2034 
2035 #undef __FUNCT__
2036 #define __FUNCT__ "TSGetApplicationContext"
2037 /*@
2038     TSGetApplicationContext - Gets the user-defined context for the
2039     timestepper.
2040 
2041     Not Collective
2042 
2043     Input Parameter:
2044 .   ts - the TS context obtained from TSCreate()
2045 
2046     Output Parameter:
2047 .   usrP - user context
2048 
2049    Fortran Notes: To use this from Fortran you must write a Fortran interface definition for this
2050     function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
2051 
2052     Level: intermediate
2053 
2054 .keywords: TS, timestep, get, application, context
2055 
2056 .seealso: TSSetApplicationContext()
2057 @*/
2058 PetscErrorCode  TSGetApplicationContext(TS ts,void *usrP)
2059 {
2060   PetscFunctionBegin;
2061   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2062   *(void**)usrP = ts->user;
2063   PetscFunctionReturn(0);
2064 }
2065 
2066 #undef __FUNCT__
2067 #define __FUNCT__ "TSGetTimeStepNumber"
2068 /*@
2069    TSGetTimeStepNumber - Gets the number of time steps completed.
2070 
2071    Not Collective
2072 
2073    Input Parameter:
2074 .  ts - the TS context obtained from TSCreate()
2075 
2076    Output Parameter:
2077 .  iter - number of steps completed so far
2078 
2079    Level: intermediate
2080 
2081 .keywords: TS, timestep, get, iteration, number
2082 .seealso: TSGetTime(), TSGetTimeStep(), TSSetPreStep(), TSSetPreStage(), TSSetPostStage(), TSSetPostStep()
2083 @*/
2084 PetscErrorCode  TSGetTimeStepNumber(TS ts,PetscInt *iter)
2085 {
2086   PetscFunctionBegin;
2087   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2088   PetscValidIntPointer(iter,2);
2089   *iter = ts->steps;
2090   PetscFunctionReturn(0);
2091 }
2092 
2093 #undef __FUNCT__
2094 #define __FUNCT__ "TSSetInitialTimeStep"
2095 /*@
2096    TSSetInitialTimeStep - Sets the initial timestep to be used,
2097    as well as the initial time.
2098 
2099    Logically Collective on TS
2100 
2101    Input Parameters:
2102 +  ts - the TS context obtained from TSCreate()
2103 .  initial_time - the initial time
2104 -  time_step - the size of the timestep
2105 
2106    Level: intermediate
2107 
2108 .seealso: TSSetTimeStep(), TSGetTimeStep()
2109 
2110 .keywords: TS, set, initial, timestep
2111 @*/
2112 PetscErrorCode  TSSetInitialTimeStep(TS ts,PetscReal initial_time,PetscReal time_step)
2113 {
2114   PetscErrorCode ierr;
2115 
2116   PetscFunctionBegin;
2117   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2118   ierr = TSSetTimeStep(ts,time_step);CHKERRQ(ierr);
2119   ierr = TSSetTime(ts,initial_time);CHKERRQ(ierr);
2120   PetscFunctionReturn(0);
2121 }
2122 
2123 #undef __FUNCT__
2124 #define __FUNCT__ "TSSetTimeStep"
2125 /*@
2126    TSSetTimeStep - Allows one to reset the timestep at any time,
2127    useful for simple pseudo-timestepping codes.
2128 
2129    Logically Collective on TS
2130 
2131    Input Parameters:
2132 +  ts - the TS context obtained from TSCreate()
2133 -  time_step - the size of the timestep
2134 
2135    Level: intermediate
2136 
2137 .seealso: TSSetInitialTimeStep(), TSGetTimeStep()
2138 
2139 .keywords: TS, set, timestep
2140 @*/
2141 PetscErrorCode  TSSetTimeStep(TS ts,PetscReal time_step)
2142 {
2143   PetscFunctionBegin;
2144   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2145   PetscValidLogicalCollectiveReal(ts,time_step,2);
2146   ts->time_step = time_step;
2147   PetscFunctionReturn(0);
2148 }
2149 
2150 #undef __FUNCT__
2151 #define __FUNCT__ "TSSetExactFinalTime"
2152 /*@
2153    TSSetExactFinalTime - Determines whether to adapt the final time step to
2154      match the exact final time, interpolate solution to the exact final time,
2155      or just return at the final time TS computed.
2156 
2157   Logically Collective on TS
2158 
2159    Input Parameter:
2160 +   ts - the time-step context
2161 -   eftopt - exact final time option
2162 
2163 $  TS_EXACTFINALTIME_STEPOVER    - Don't do anything if final time is exceeded
2164 $  TS_EXACTFINALTIME_INTERPOLATE - Interpolate back to final time
2165 $  TS_EXACTFINALTIME_MATCHSTEP - Adapt final time step to match the final time
2166 
2167    Options Database:
2168 .   -ts_exact_final_time <stepover,interpolate,matchstep> - select the final step at runtime
2169 
2170    Warning: If you use the option TS_EXACTFINALTIME_STEPOVER the solution may be at a very different time
2171     then the final time you selected.
2172 
2173    Level: beginner
2174 
2175 .seealso: TSExactFinalTimeOption
2176 @*/
2177 PetscErrorCode  TSSetExactFinalTime(TS ts,TSExactFinalTimeOption eftopt)
2178 {
2179   PetscFunctionBegin;
2180   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2181   PetscValidLogicalCollectiveEnum(ts,eftopt,2);
2182   ts->exact_final_time = eftopt;
2183   PetscFunctionReturn(0);
2184 }
2185 
2186 #undef __FUNCT__
2187 #define __FUNCT__ "TSGetTimeStep"
2188 /*@
2189    TSGetTimeStep - Gets the current timestep size.
2190 
2191    Not Collective
2192 
2193    Input Parameter:
2194 .  ts - the TS context obtained from TSCreate()
2195 
2196    Output Parameter:
2197 .  dt - the current timestep size
2198 
2199    Level: intermediate
2200 
2201 .seealso: TSSetInitialTimeStep(), TSGetTimeStep()
2202 
2203 .keywords: TS, get, timestep
2204 @*/
2205 PetscErrorCode  TSGetTimeStep(TS ts,PetscReal *dt)
2206 {
2207   PetscFunctionBegin;
2208   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2209   PetscValidRealPointer(dt,2);
2210   *dt = ts->time_step;
2211   PetscFunctionReturn(0);
2212 }
2213 
2214 #undef __FUNCT__
2215 #define __FUNCT__ "TSGetSolution"
2216 /*@
2217    TSGetSolution - Returns the solution at the present timestep. It
2218    is valid to call this routine inside the function that you are evaluating
2219    in order to move to the new timestep. This vector not changed until
2220    the solution at the next timestep has been calculated.
2221 
2222    Not Collective, but Vec returned is parallel if TS is parallel
2223 
2224    Input Parameter:
2225 .  ts - the TS context obtained from TSCreate()
2226 
2227    Output Parameter:
2228 .  v - the vector containing the solution
2229 
2230    Note: If you used TSSetExactFinalTime(ts,TS_EXACTFINALTIME_MATCHSTEP); this does not return the solution at the requested
2231    final time. It returns the solution at the next timestep.
2232 
2233    Level: intermediate
2234 
2235 .seealso: TSGetTimeStep(), TSGetTime(), TSGetSolveTime(), TSGetAuxSolution()
2236 
2237 .keywords: TS, timestep, get, solution
2238 @*/
2239 PetscErrorCode  TSGetSolution(TS ts,Vec *v)
2240 {
2241   PetscFunctionBegin;
2242   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2243   PetscValidPointer(v,2);
2244   *v = ts->vec_sol;
2245   PetscFunctionReturn(0);
2246 }
2247 
2248 #undef __FUNCT__
2249 #define __FUNCT__ "TSGetAuxSolution"
2250 /*@
2251    TSGetAuxSolution - Returns any auxiliary solutions at the present
2252    timestep, if available for the time integration method being used.
2253    Auxiliary solutions are quantities that share the same size and
2254    structure as the solution vector.
2255 
2256    Not Collective, but Vec returned is parallel if TS is parallel
2257 
2258    Parameters :
2259 .  ts - the TS context obtained from TSCreate() (input parameter).
2260 .  n - If v is PETSC_NULL, then the number of auxiliary solutions is
2261        returned through n, else the n-th auxiliary solution is
2262        returned in v.
2263 .  v - the vector containing the n-th auxiliary solution
2264        (may be PETSC_NULL to use this function to find out
2265         the number of auxiliary solutions).
2266 
2267    Level: intermediate
2268 
2269 .seealso: TSGetSolution()
2270 
2271 .keywords: TS, timestep, get, solution
2272 @*/
2273 PetscErrorCode  TSGetAuxSolution(TS ts,PetscInt *n,Vec *v)
2274 {
2275   PetscErrorCode ierr;
2276 
2277   PetscFunctionBegin;
2278   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2279   if (!ts->ops->getauxsolution) *n = 0;
2280   else {
2281     ierr = (*ts->ops->getauxsolution)(ts,n,v);CHKERRQ(ierr);
2282   }
2283   PetscFunctionReturn(0);
2284 }
2285 
2286 #undef __FUNCT__
2287 #define __FUNCT__ "TSGetCostGradients"
2288 /*@
2289    TSGetCostGradients - Returns the gradients from the TSAdjointSolve()
2290 
2291    Not Collective, but Vec returned is parallel if TS is parallel
2292 
2293    Input Parameter:
2294 .  ts - the TS context obtained from TSCreate()
2295 
2296    Output Parameter:
2297 +  lambda - vectors containing the gradients of the cost functions with respect to the ODE/DAE solution variables
2298 -  mu - vectors containing the gradients of the cost functions with respect to the problem parameters
2299 
2300    Level: intermediate
2301 
2302 .seealso: TSGetTimeStep()
2303 
2304 .keywords: TS, timestep, get, sensitivity
2305 @*/
2306 PetscErrorCode  TSGetCostGradients(TS ts,PetscInt *numcost,Vec **lambda,Vec **mu)
2307 {
2308   PetscFunctionBegin;
2309   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2310   if (numcost) *numcost = ts->numcost;
2311   if (lambda)  *lambda  = ts->vecs_sensi;
2312   if (mu)      *mu      = ts->vecs_sensip;
2313   PetscFunctionReturn(0);
2314 }
2315 
2316 /* ----- Routines to initialize and destroy a timestepper ---- */
2317 #undef __FUNCT__
2318 #define __FUNCT__ "TSSetProblemType"
2319 /*@
2320   TSSetProblemType - Sets the type of problem to be solved.
2321 
2322   Not collective
2323 
2324   Input Parameters:
2325 + ts   - The TS
2326 - type - One of TS_LINEAR, TS_NONLINEAR where these types refer to problems of the forms
2327 .vb
2328          U_t - A U = 0      (linear)
2329          U_t - A(t) U = 0   (linear)
2330          F(t,U,U_t) = 0     (nonlinear)
2331 .ve
2332 
2333    Level: beginner
2334 
2335 .keywords: TS, problem type
2336 .seealso: TSSetUp(), TSProblemType, TS
2337 @*/
2338 PetscErrorCode  TSSetProblemType(TS ts, TSProblemType type)
2339 {
2340   PetscErrorCode ierr;
2341 
2342   PetscFunctionBegin;
2343   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2344   ts->problem_type = type;
2345   if (type == TS_LINEAR) {
2346     SNES snes;
2347     ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2348     ierr = SNESSetType(snes,SNESKSPONLY);CHKERRQ(ierr);
2349   }
2350   PetscFunctionReturn(0);
2351 }
2352 
2353 #undef __FUNCT__
2354 #define __FUNCT__ "TSGetProblemType"
2355 /*@C
2356   TSGetProblemType - Gets the type of problem to be solved.
2357 
2358   Not collective
2359 
2360   Input Parameter:
2361 . ts   - The TS
2362 
2363   Output Parameter:
2364 . type - One of TS_LINEAR, TS_NONLINEAR where these types refer to problems of the forms
2365 .vb
2366          M U_t = A U
2367          M(t) U_t = A(t) U
2368          F(t,U,U_t)
2369 .ve
2370 
2371    Level: beginner
2372 
2373 .keywords: TS, problem type
2374 .seealso: TSSetUp(), TSProblemType, TS
2375 @*/
2376 PetscErrorCode  TSGetProblemType(TS ts, TSProblemType *type)
2377 {
2378   PetscFunctionBegin;
2379   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2380   PetscValidIntPointer(type,2);
2381   *type = ts->problem_type;
2382   PetscFunctionReturn(0);
2383 }
2384 
2385 #undef __FUNCT__
2386 #define __FUNCT__ "TSSetUp"
2387 /*@
2388    TSSetUp - Sets up the internal data structures for the later use
2389    of a timestepper.
2390 
2391    Collective on TS
2392 
2393    Input Parameter:
2394 .  ts - the TS context obtained from TSCreate()
2395 
2396    Notes:
2397    For basic use of the TS solvers the user need not explicitly call
2398    TSSetUp(), since these actions will automatically occur during
2399    the call to TSStep().  However, if one wishes to control this
2400    phase separately, TSSetUp() should be called after TSCreate()
2401    and optional routines of the form TSSetXXX(), but before TSStep().
2402 
2403    Level: advanced
2404 
2405 .keywords: TS, timestep, setup
2406 
2407 .seealso: TSCreate(), TSStep(), TSDestroy()
2408 @*/
2409 PetscErrorCode  TSSetUp(TS ts)
2410 {
2411   PetscErrorCode ierr;
2412   DM             dm;
2413   PetscErrorCode (*func)(SNES,Vec,Vec,void*);
2414   PetscErrorCode (*jac)(SNES,Vec,Mat,Mat,void*);
2415   TSIFunction    ifun;
2416   TSIJacobian    ijac;
2417   TSI2Jacobian   i2jac;
2418   TSRHSJacobian  rhsjac;
2419 
2420   PetscFunctionBegin;
2421   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2422   if (ts->setupcalled) PetscFunctionReturn(0);
2423 
2424   ts->total_steps = 0;
2425   if (!((PetscObject)ts)->type_name) {
2426     ierr = TSGetIFunction(ts,NULL,&ifun,NULL);CHKERRQ(ierr);
2427     ierr = TSSetType(ts,ifun ? TSBEULER : TSEULER);CHKERRQ(ierr);
2428   }
2429 
2430   if (!ts->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call TSSetSolution() first");
2431 
2432   if (ts->rhsjacobian.reuse) {
2433     Mat Amat,Pmat;
2434     SNES snes;
2435     ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2436     ierr = SNESGetJacobian(snes,&Amat,&Pmat,NULL,NULL);CHKERRQ(ierr);
2437     /* Matching matrices implies that an IJacobian is NOT set, because if it had been set, the IJacobian's matrix would
2438      * have displaced the RHS matrix */
2439     if (Amat == ts->Arhs) {
2440       ierr = MatDuplicate(ts->Arhs,MAT_DO_NOT_COPY_VALUES,&Amat);CHKERRQ(ierr);
2441       ierr = SNESSetJacobian(snes,Amat,NULL,NULL,NULL);CHKERRQ(ierr);
2442       ierr = MatDestroy(&Amat);CHKERRQ(ierr);
2443     }
2444     if (Pmat == ts->Brhs) {
2445       ierr = MatDuplicate(ts->Brhs,MAT_DO_NOT_COPY_VALUES,&Pmat);CHKERRQ(ierr);
2446       ierr = SNESSetJacobian(snes,NULL,Pmat,NULL,NULL);CHKERRQ(ierr);
2447       ierr = MatDestroy(&Pmat);CHKERRQ(ierr);
2448     }
2449   }
2450   if (ts->ops->setup) {
2451     ierr = (*ts->ops->setup)(ts);CHKERRQ(ierr);
2452   }
2453 
2454   /* In the case where we've set a DMTSFunction or what have you, we need the default SNESFunction
2455      to be set right but can't do it elsewhere due to the overreliance on ctx=ts.
2456    */
2457   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
2458   ierr = DMSNESGetFunction(dm,&func,NULL);CHKERRQ(ierr);
2459   if (!func) {
2460     ierr = DMSNESSetFunction(dm,SNESTSFormFunction,ts);CHKERRQ(ierr);
2461   }
2462   /* If the SNES doesn't have a jacobian set and the TS has an ijacobian or rhsjacobian set, set the SNES to use it.
2463      Otherwise, the SNES will use coloring internally to form the Jacobian.
2464    */
2465   ierr = DMSNESGetJacobian(dm,&jac,NULL);CHKERRQ(ierr);
2466   ierr = DMTSGetIJacobian(dm,&ijac,NULL);CHKERRQ(ierr);
2467   ierr = DMTSGetI2Jacobian(dm,&i2jac,NULL);CHKERRQ(ierr);
2468   ierr = DMTSGetRHSJacobian(dm,&rhsjac,NULL);CHKERRQ(ierr);
2469   if (!jac && (ijac || i2jac || rhsjac)) {
2470     ierr = DMSNESSetJacobian(dm,SNESTSFormJacobian,ts);CHKERRQ(ierr);
2471   }
2472 
2473   /* if time integration scheme has a starting method, call it */
2474   if (ts->ops->startingmethod) {
2475     ierr = (*ts->ops->startingmethod)(ts);CHKERRQ(ierr);
2476   }
2477 
2478   ts->setupcalled = PETSC_TRUE;
2479   PetscFunctionReturn(0);
2480 }
2481 
2482 #undef __FUNCT__
2483 #define __FUNCT__ "TSAdjointSetUp"
2484 /*@
2485    TSAdjointSetUp - Sets up the internal data structures for the later use
2486    of an adjoint solver
2487 
2488    Collective on TS
2489 
2490    Input Parameter:
2491 .  ts - the TS context obtained from TSCreate()
2492 
2493    Level: advanced
2494 
2495 .keywords: TS, timestep, setup
2496 
2497 .seealso: TSCreate(), TSAdjointStep(), TSSetCostGradients()
2498 @*/
2499 PetscErrorCode  TSAdjointSetUp(TS ts)
2500 {
2501   PetscErrorCode ierr;
2502 
2503   PetscFunctionBegin;
2504   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2505   if (ts->adjointsetupcalled) PetscFunctionReturn(0);
2506   if (!ts->vecs_sensi) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call TSSetCostGradients() first");
2507 
2508   if (ts->vec_costintegral) { /* if there is integral in the cost function*/
2509     ierr = VecDuplicateVecs(ts->vecs_sensi[0],ts->numcost,&ts->vecs_drdy);CHKERRQ(ierr);
2510     if (ts->vecs_sensip){
2511       ierr = VecDuplicateVecs(ts->vecs_sensip[0],ts->numcost,&ts->vecs_drdp);CHKERRQ(ierr);
2512     }
2513   }
2514 
2515   if (ts->ops->adjointsetup) {
2516     ierr = (*ts->ops->adjointsetup)(ts);CHKERRQ(ierr);
2517   }
2518   ts->adjointsetupcalled = PETSC_TRUE;
2519   PetscFunctionReturn(0);
2520 }
2521 
2522 #undef __FUNCT__
2523 #define __FUNCT__ "TSReset"
2524 /*@
2525    TSReset - Resets a TS context and removes any allocated Vecs and Mats.
2526 
2527    Collective on TS
2528 
2529    Input Parameter:
2530 .  ts - the TS context obtained from TSCreate()
2531 
2532    Level: beginner
2533 
2534 .keywords: TS, timestep, reset
2535 
2536 .seealso: TSCreate(), TSSetup(), TSDestroy()
2537 @*/
2538 PetscErrorCode  TSReset(TS ts)
2539 {
2540   PetscErrorCode ierr;
2541 
2542   PetscFunctionBegin;
2543   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2544 
2545   if (ts->ops->reset) {
2546     ierr = (*ts->ops->reset)(ts);CHKERRQ(ierr);
2547   }
2548   if (ts->snes) {ierr = SNESReset(ts->snes);CHKERRQ(ierr);}
2549   if (ts->adapt) {ierr = TSAdaptReset(ts->adapt);CHKERRQ(ierr);}
2550 
2551   ierr = MatDestroy(&ts->Arhs);CHKERRQ(ierr);
2552   ierr = MatDestroy(&ts->Brhs);CHKERRQ(ierr);
2553   ierr = VecDestroy(&ts->Frhs);CHKERRQ(ierr);
2554   ierr = VecDestroy(&ts->vec_sol);CHKERRQ(ierr);
2555   ierr = VecDestroy(&ts->vec_dot);CHKERRQ(ierr);
2556   ierr = VecDestroy(&ts->vatol);CHKERRQ(ierr);
2557   ierr = VecDestroy(&ts->vrtol);CHKERRQ(ierr);
2558   ierr = VecDestroyVecs(ts->nwork,&ts->work);CHKERRQ(ierr);
2559 
2560  if (ts->vec_costintegral) {
2561     ierr = VecDestroyVecs(ts->numcost,&ts->vecs_drdy);CHKERRQ(ierr);
2562     if (ts->vecs_drdp){
2563       ierr = VecDestroyVecs(ts->numcost,&ts->vecs_drdp);CHKERRQ(ierr);
2564     }
2565   }
2566   ts->vecs_sensi  = NULL;
2567   ts->vecs_sensip = NULL;
2568   ierr = MatDestroy(&ts->Jacp);CHKERRQ(ierr);
2569   ierr = VecDestroy(&ts->vec_costintegral);CHKERRQ(ierr);
2570   ierr = VecDestroy(&ts->vec_costintegrand);CHKERRQ(ierr);
2571   ts->setupcalled = PETSC_FALSE;
2572   PetscFunctionReturn(0);
2573 }
2574 
2575 #undef __FUNCT__
2576 #define __FUNCT__ "TSDestroy"
2577 /*@
2578    TSDestroy - Destroys the timestepper context that was created
2579    with TSCreate().
2580 
2581    Collective on TS
2582 
2583    Input Parameter:
2584 .  ts - the TS context obtained from TSCreate()
2585 
2586    Level: beginner
2587 
2588 .keywords: TS, timestepper, destroy
2589 
2590 .seealso: TSCreate(), TSSetUp(), TSSolve()
2591 @*/
2592 PetscErrorCode  TSDestroy(TS *ts)
2593 {
2594   PetscErrorCode ierr;
2595 
2596   PetscFunctionBegin;
2597   if (!*ts) PetscFunctionReturn(0);
2598   PetscValidHeaderSpecific((*ts),TS_CLASSID,1);
2599   if (--((PetscObject)(*ts))->refct > 0) {*ts = 0; PetscFunctionReturn(0);}
2600 
2601   ierr = TSReset((*ts));CHKERRQ(ierr);
2602 
2603   /* if memory was published with SAWs then destroy it */
2604   ierr = PetscObjectSAWsViewOff((PetscObject)*ts);CHKERRQ(ierr);
2605   if ((*ts)->ops->destroy) {ierr = (*(*ts)->ops->destroy)((*ts));CHKERRQ(ierr);}
2606 
2607   ierr = TSTrajectoryDestroy(&(*ts)->trajectory);CHKERRQ(ierr);
2608 
2609   ierr = TSAdaptDestroy(&(*ts)->adapt);CHKERRQ(ierr);
2610   ierr = TSEventDestroy(&(*ts)->event);CHKERRQ(ierr);
2611 
2612   ierr = SNESDestroy(&(*ts)->snes);CHKERRQ(ierr);
2613   ierr = DMDestroy(&(*ts)->dm);CHKERRQ(ierr);
2614   ierr = TSMonitorCancel((*ts));CHKERRQ(ierr);
2615   ierr = TSAdjointMonitorCancel((*ts));CHKERRQ(ierr);
2616 
2617   ierr = PetscHeaderDestroy(ts);CHKERRQ(ierr);
2618   PetscFunctionReturn(0);
2619 }
2620 
2621 #undef __FUNCT__
2622 #define __FUNCT__ "TSGetSNES"
2623 /*@
2624    TSGetSNES - Returns the SNES (nonlinear solver) associated with
2625    a TS (timestepper) context. Valid only for nonlinear problems.
2626 
2627    Not Collective, but SNES is parallel if TS is parallel
2628 
2629    Input Parameter:
2630 .  ts - the TS context obtained from TSCreate()
2631 
2632    Output Parameter:
2633 .  snes - the nonlinear solver context
2634 
2635    Notes:
2636    The user can then directly manipulate the SNES context to set various
2637    options, etc.  Likewise, the user can then extract and manipulate the
2638    KSP, KSP, and PC contexts as well.
2639 
2640    TSGetSNES() does not work for integrators that do not use SNES; in
2641    this case TSGetSNES() returns NULL in snes.
2642 
2643    Level: beginner
2644 
2645 .keywords: timestep, get, SNES
2646 @*/
2647 PetscErrorCode  TSGetSNES(TS ts,SNES *snes)
2648 {
2649   PetscErrorCode ierr;
2650 
2651   PetscFunctionBegin;
2652   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2653   PetscValidPointer(snes,2);
2654   if (!ts->snes) {
2655     ierr = SNESCreate(PetscObjectComm((PetscObject)ts),&ts->snes);CHKERRQ(ierr);
2656     ierr = SNESSetFunction(ts->snes,NULL,SNESTSFormFunction,ts);CHKERRQ(ierr);
2657     ierr = PetscLogObjectParent((PetscObject)ts,(PetscObject)ts->snes);CHKERRQ(ierr);
2658     ierr = PetscObjectIncrementTabLevel((PetscObject)ts->snes,(PetscObject)ts,1);CHKERRQ(ierr);
2659     if (ts->dm) {ierr = SNESSetDM(ts->snes,ts->dm);CHKERRQ(ierr);}
2660     if (ts->problem_type == TS_LINEAR) {
2661       ierr = SNESSetType(ts->snes,SNESKSPONLY);CHKERRQ(ierr);
2662     }
2663   }
2664   *snes = ts->snes;
2665   PetscFunctionReturn(0);
2666 }
2667 
2668 #undef __FUNCT__
2669 #define __FUNCT__ "TSSetSNES"
2670 /*@
2671    TSSetSNES - Set the SNES (nonlinear solver) to be used by the timestepping context
2672 
2673    Collective
2674 
2675    Input Parameter:
2676 +  ts - the TS context obtained from TSCreate()
2677 -  snes - the nonlinear solver context
2678 
2679    Notes:
2680    Most users should have the TS created by calling TSGetSNES()
2681 
2682    Level: developer
2683 
2684 .keywords: timestep, set, SNES
2685 @*/
2686 PetscErrorCode TSSetSNES(TS ts,SNES snes)
2687 {
2688   PetscErrorCode ierr;
2689   PetscErrorCode (*func)(SNES,Vec,Mat,Mat,void*);
2690 
2691   PetscFunctionBegin;
2692   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2693   PetscValidHeaderSpecific(snes,SNES_CLASSID,2);
2694   ierr = PetscObjectReference((PetscObject)snes);CHKERRQ(ierr);
2695   ierr = SNESDestroy(&ts->snes);CHKERRQ(ierr);
2696 
2697   ts->snes = snes;
2698 
2699   ierr = SNESSetFunction(ts->snes,NULL,SNESTSFormFunction,ts);CHKERRQ(ierr);
2700   ierr = SNESGetJacobian(ts->snes,NULL,NULL,&func,NULL);CHKERRQ(ierr);
2701   if (func == SNESTSFormJacobian) {
2702     ierr = SNESSetJacobian(ts->snes,NULL,NULL,SNESTSFormJacobian,ts);CHKERRQ(ierr);
2703   }
2704   PetscFunctionReturn(0);
2705 }
2706 
2707 #undef __FUNCT__
2708 #define __FUNCT__ "TSGetKSP"
2709 /*@
2710    TSGetKSP - Returns the KSP (linear solver) associated with
2711    a TS (timestepper) context.
2712 
2713    Not Collective, but KSP is parallel if TS is parallel
2714 
2715    Input Parameter:
2716 .  ts - the TS context obtained from TSCreate()
2717 
2718    Output Parameter:
2719 .  ksp - the nonlinear solver context
2720 
2721    Notes:
2722    The user can then directly manipulate the KSP context to set various
2723    options, etc.  Likewise, the user can then extract and manipulate the
2724    KSP and PC contexts as well.
2725 
2726    TSGetKSP() does not work for integrators that do not use KSP;
2727    in this case TSGetKSP() returns NULL in ksp.
2728 
2729    Level: beginner
2730 
2731 .keywords: timestep, get, KSP
2732 @*/
2733 PetscErrorCode  TSGetKSP(TS ts,KSP *ksp)
2734 {
2735   PetscErrorCode ierr;
2736   SNES           snes;
2737 
2738   PetscFunctionBegin;
2739   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2740   PetscValidPointer(ksp,2);
2741   if (!((PetscObject)ts)->type_name) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"KSP is not created yet. Call TSSetType() first");
2742   if (ts->problem_type != TS_LINEAR) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Linear only; use TSGetSNES()");
2743   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2744   ierr = SNESGetKSP(snes,ksp);CHKERRQ(ierr);
2745   PetscFunctionReturn(0);
2746 }
2747 
2748 /* ----------- Routines to set solver parameters ---------- */
2749 
2750 #undef __FUNCT__
2751 #define __FUNCT__ "TSGetDuration"
2752 /*@
2753    TSGetDuration - Gets the maximum number of timesteps to use and
2754    maximum time for iteration.
2755 
2756    Not Collective
2757 
2758    Input Parameters:
2759 +  ts       - the TS context obtained from TSCreate()
2760 .  maxsteps - maximum number of iterations to use, or NULL
2761 -  maxtime  - final time to iterate to, or NULL
2762 
2763    Level: intermediate
2764 
2765 .keywords: TS, timestep, get, maximum, iterations, time
2766 @*/
2767 PetscErrorCode  TSGetDuration(TS ts, PetscInt *maxsteps, PetscReal *maxtime)
2768 {
2769   PetscFunctionBegin;
2770   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2771   if (maxsteps) {
2772     PetscValidIntPointer(maxsteps,2);
2773     *maxsteps = ts->max_steps;
2774   }
2775   if (maxtime) {
2776     PetscValidScalarPointer(maxtime,3);
2777     *maxtime = ts->max_time;
2778   }
2779   PetscFunctionReturn(0);
2780 }
2781 
2782 #undef __FUNCT__
2783 #define __FUNCT__ "TSSetDuration"
2784 /*@
2785    TSSetDuration - Sets the maximum number of timesteps to use and
2786    maximum time for iteration.
2787 
2788    Logically Collective on TS
2789 
2790    Input Parameters:
2791 +  ts - the TS context obtained from TSCreate()
2792 .  maxsteps - maximum number of iterations to use
2793 -  maxtime - final time to iterate to
2794 
2795    Options Database Keys:
2796 .  -ts_max_steps <maxsteps> - Sets maxsteps
2797 .  -ts_final_time <maxtime> - Sets maxtime
2798 
2799    Notes:
2800    The default maximum number of iterations is 5000. Default time is 5.0
2801 
2802    Level: intermediate
2803 
2804 .keywords: TS, timestep, set, maximum, iterations
2805 
2806 .seealso: TSSetExactFinalTime()
2807 @*/
2808 PetscErrorCode  TSSetDuration(TS ts,PetscInt maxsteps,PetscReal maxtime)
2809 {
2810   PetscFunctionBegin;
2811   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2812   PetscValidLogicalCollectiveInt(ts,maxsteps,2);
2813   PetscValidLogicalCollectiveReal(ts,maxtime,2);
2814   if (maxsteps >= 0) ts->max_steps = maxsteps;
2815   if (maxtime != PETSC_DEFAULT) ts->max_time = maxtime;
2816   PetscFunctionReturn(0);
2817 }
2818 
2819 #undef __FUNCT__
2820 #define __FUNCT__ "TSSetSolution"
2821 /*@
2822    TSSetSolution - Sets the initial solution vector
2823    for use by the TS routines.
2824 
2825    Logically Collective on TS and Vec
2826 
2827    Input Parameters:
2828 +  ts - the TS context obtained from TSCreate()
2829 -  u - the solution vector
2830 
2831    Level: beginner
2832 
2833 .keywords: TS, timestep, set, solution, initial conditions
2834 @*/
2835 PetscErrorCode  TSSetSolution(TS ts,Vec u)
2836 {
2837   PetscErrorCode ierr;
2838   DM             dm;
2839 
2840   PetscFunctionBegin;
2841   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2842   PetscValidHeaderSpecific(u,VEC_CLASSID,2);
2843   ierr = PetscObjectReference((PetscObject)u);CHKERRQ(ierr);
2844   ierr = VecDestroy(&ts->vec_sol);CHKERRQ(ierr);
2845   ts->vec_sol = u;
2846 
2847   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
2848   ierr = DMShellSetGlobalVector(dm,u);CHKERRQ(ierr);
2849   PetscFunctionReturn(0);
2850 }
2851 
2852 #undef __FUNCT__
2853 #define __FUNCT__ "TSAdjointSetSteps"
2854 /*@
2855    TSAdjointSetSteps - Sets the number of steps the adjoint solver should take backward in time
2856 
2857    Logically Collective on TS
2858 
2859    Input Parameters:
2860 +  ts - the TS context obtained from TSCreate()
2861 .  steps - number of steps to use
2862 
2863    Level: intermediate
2864 
2865    Notes: Normally one does not call this and TSAdjointSolve() integrates back to the original timestep. One can call this
2866           so as to integrate back to less than the original timestep
2867 
2868 .keywords: TS, timestep, set, maximum, iterations
2869 
2870 .seealso: TSSetExactFinalTime()
2871 @*/
2872 PetscErrorCode  TSAdjointSetSteps(TS ts,PetscInt steps)
2873 {
2874   PetscFunctionBegin;
2875   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2876   PetscValidLogicalCollectiveInt(ts,steps,2);
2877   if (steps < 0) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_OUTOFRANGE,"Cannot step back a negative number of steps");
2878   if (steps > ts->total_steps) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_OUTOFRANGE,"Cannot step back more than the total number of forward steps");
2879   ts->adjoint_max_steps = steps;
2880   PetscFunctionReturn(0);
2881 }
2882 
2883 #undef __FUNCT__
2884 #define __FUNCT__ "TSSetCostGradients"
2885 /*@
2886    TSSetCostGradients - Sets the initial value of the gradients of the cost function w.r.t. initial conditions and w.r.t. the problem parameters
2887       for use by the TSAdjoint routines.
2888 
2889    Logically Collective on TS and Vec
2890 
2891    Input Parameters:
2892 +  ts - the TS context obtained from TSCreate()
2893 .  lambda - gradients with respect to the initial condition variables, the dimension and parallel layout of these vectors is the same as the ODE solution vector
2894 -  mu - gradients with respect to the parameters, the number of entries in these vectors is the same as the number of parameters
2895 
2896    Level: beginner
2897 
2898    Notes: the entries in these vectors must be correctly initialized with the values lamda_i = df/dy|finaltime  mu_i = df/dp|finaltime
2899 
2900 .keywords: TS, timestep, set, sensitivity, initial conditions
2901 @*/
2902 PetscErrorCode  TSSetCostGradients(TS ts,PetscInt numcost,Vec *lambda,Vec *mu)
2903 {
2904   PetscFunctionBegin;
2905   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2906   PetscValidPointer(lambda,2);
2907   ts->vecs_sensi  = lambda;
2908   ts->vecs_sensip = mu;
2909   if (ts->numcost && ts->numcost!=numcost) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"The number of cost functions (2rd parameter of TSSetCostIntegrand()) is inconsistent with the one set by TSSetCostIntegrand");
2910   ts->numcost  = numcost;
2911   PetscFunctionReturn(0);
2912 }
2913 
2914 #undef __FUNCT__
2915 #define __FUNCT__ "TSAdjointSetRHSJacobian"
2916 /*@C
2917   TSAdjointSetRHSJacobian - Sets the function that computes the Jacobian of G w.r.t. the parameters p where y_t = G(y,p,t), as well as the location to store the matrix.
2918 
2919   Logically Collective on TS
2920 
2921   Input Parameters:
2922 + ts   - The TS context obtained from TSCreate()
2923 - func - The function
2924 
2925   Calling sequence of func:
2926 $ func (TS ts,PetscReal t,Vec y,Mat A,void *ctx);
2927 +   t - current timestep
2928 .   y - input vector (current ODE solution)
2929 .   A - output matrix
2930 -   ctx - [optional] user-defined function context
2931 
2932   Level: intermediate
2933 
2934   Notes: Amat has the same number of rows and the same row parallel layout as u, Amat has the same number of columns and parallel layout as p
2935 
2936 .keywords: TS, sensitivity
2937 .seealso:
2938 @*/
2939 PetscErrorCode  TSAdjointSetRHSJacobian(TS ts,Mat Amat,PetscErrorCode (*func)(TS,PetscReal,Vec,Mat,void*),void *ctx)
2940 {
2941   PetscErrorCode ierr;
2942 
2943   PetscFunctionBegin;
2944   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2945   if (Amat) PetscValidHeaderSpecific(Amat,MAT_CLASSID,2);
2946 
2947   ts->rhsjacobianp    = func;
2948   ts->rhsjacobianpctx = ctx;
2949   if(Amat) {
2950     ierr = PetscObjectReference((PetscObject)Amat);CHKERRQ(ierr);
2951     ierr = MatDestroy(&ts->Jacp);CHKERRQ(ierr);
2952     ts->Jacp = Amat;
2953   }
2954   PetscFunctionReturn(0);
2955 }
2956 
2957 #undef __FUNCT__
2958 #define __FUNCT__ "TSAdjointComputeRHSJacobian"
2959 /*@C
2960   TSAdjointComputeRHSJacobian - Runs the user-defined Jacobian function.
2961 
2962   Collective on TS
2963 
2964   Input Parameters:
2965 . ts   - The TS context obtained from TSCreate()
2966 
2967   Level: developer
2968 
2969 .keywords: TS, sensitivity
2970 .seealso: TSAdjointSetRHSJacobian()
2971 @*/
2972 PetscErrorCode  TSAdjointComputeRHSJacobian(TS ts,PetscReal t,Vec X,Mat Amat)
2973 {
2974   PetscErrorCode ierr;
2975 
2976   PetscFunctionBegin;
2977   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2978   PetscValidHeaderSpecific(X,VEC_CLASSID,3);
2979   PetscValidPointer(Amat,4);
2980 
2981   PetscStackPush("TS user JacobianP function for sensitivity analysis");
2982   ierr = (*ts->rhsjacobianp)(ts,t,X,Amat,ts->rhsjacobianpctx); CHKERRQ(ierr);
2983   PetscStackPop;
2984   PetscFunctionReturn(0);
2985 }
2986 
2987 #undef __FUNCT__
2988 #define __FUNCT__ "TSSetCostIntegrand"
2989 /*@C
2990     TSSetCostIntegrand - Sets the routine for evaluating the integral term in one or more cost functions
2991 
2992     Logically Collective on TS
2993 
2994     Input Parameters:
2995 +   ts - the TS context obtained from TSCreate()
2996 .   numcost - number of gradients to be computed, this is the number of cost functions
2997 .   rf - routine for evaluating the integrand function
2998 .   drdyf - function that computes the gradients of the r's with respect to y,NULL if not a function y
2999 .   drdpf - function that computes the gradients of the r's with respect to p, NULL if not a function of p
3000 .   fwd - flag indicating whether to evaluate cost integral in the forward run or the adjoint run
3001 -   ctx - [optional] user-defined context for private data for the function evaluation routine (may be NULL)
3002 
3003     Calling sequence of rf:
3004 $     rf(TS ts,PetscReal t,Vec y,Vec f[],void *ctx);
3005 
3006 +   t - current timestep
3007 .   y - input vector
3008 .   f - function result; one vector entry for each cost function
3009 -   ctx - [optional] user-defined function context
3010 
3011    Calling sequence of drdyf:
3012 $    PetscErroCode drdyf(TS ts,PetscReal t,Vec y,Vec *drdy,void *ctx);
3013 
3014    Calling sequence of drdpf:
3015 $    PetscErroCode drdpf(TS ts,PetscReal t,Vec y,Vec *drdp,void *ctx);
3016 
3017     Level: intermediate
3018 
3019     Notes: For optimization there is generally a single cost function, numcost = 1. For sensitivities there may be multiple cost functions
3020 
3021 .keywords: TS, sensitivity analysis, timestep, set, quadrature, function
3022 
3023 .seealso: TSAdjointSetRHSJacobian(),TSGetCostGradients(), TSSetCostGradients()
3024 @*/
3025 PetscErrorCode  TSSetCostIntegrand(TS ts,PetscInt numcost,PetscErrorCode (*rf)(TS,PetscReal,Vec,Vec,void*),
3026                                                           PetscErrorCode (*drdyf)(TS,PetscReal,Vec,Vec*,void*),
3027                                                           PetscErrorCode (*drdpf)(TS,PetscReal,Vec,Vec*,void*),
3028                                                           PetscBool fwd,void *ctx)
3029 {
3030   PetscErrorCode ierr;
3031 
3032   PetscFunctionBegin;
3033   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3034   if (ts->numcost && ts->numcost!=numcost) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"The number of cost functions (2rd parameter of TSSetCostIntegrand()) is inconsistent with the one set by TSSetCostGradients()");
3035   if (!ts->numcost) ts->numcost=numcost;
3036 
3037   ts->costintegralfwd  = fwd; /* Evaluate the cost integral in forward run if fwd is true */
3038   ierr                 = VecCreateSeq(PETSC_COMM_SELF,numcost,&ts->vec_costintegral);CHKERRQ(ierr);
3039   ierr                 = VecDuplicate(ts->vec_costintegral,&ts->vec_costintegrand);CHKERRQ(ierr);
3040   ts->costintegrand    = rf;
3041   ts->costintegrandctx = ctx;
3042   ts->drdyfunction     = drdyf;
3043   ts->drdpfunction     = drdpf;
3044   PetscFunctionReturn(0);
3045 }
3046 
3047 #undef __FUNCT__
3048 #define __FUNCT__ "TSGetCostIntegral"
3049 /*@
3050    TSGetCostIntegral - Returns the values of the integral term in the cost functions.
3051    It is valid to call the routine after a backward run.
3052 
3053    Not Collective
3054 
3055    Input Parameter:
3056 .  ts - the TS context obtained from TSCreate()
3057 
3058    Output Parameter:
3059 .  v - the vector containing the integrals for each cost function
3060 
3061    Level: intermediate
3062 
3063 .seealso: TSSetCostIntegrand()
3064 
3065 .keywords: TS, sensitivity analysis
3066 @*/
3067 PetscErrorCode  TSGetCostIntegral(TS ts,Vec *v)
3068 {
3069   PetscFunctionBegin;
3070   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3071   PetscValidPointer(v,2);
3072   *v = ts->vec_costintegral;
3073   PetscFunctionReturn(0);
3074 }
3075 
3076 #undef __FUNCT__
3077 #define __FUNCT__ "TSAdjointComputeCostIntegrand"
3078 /*@
3079    TSAdjointComputeCostIntegrand - Evaluates the integral function in the cost functions.
3080 
3081    Input Parameters:
3082 +  ts - the TS context
3083 .  t - current time
3084 -  y - state vector, i.e. current solution
3085 
3086    Output Parameter:
3087 .  q - vector of size numcost to hold the outputs
3088 
3089    Note:
3090    Most users should not need to explicitly call this routine, as it
3091    is used internally within the sensitivity analysis context.
3092 
3093    Level: developer
3094 
3095 .keywords: TS, compute
3096 
3097 .seealso: TSSetCostIntegrand()
3098 @*/
3099 PetscErrorCode TSAdjointComputeCostIntegrand(TS ts,PetscReal t,Vec y,Vec q)
3100 {
3101   PetscErrorCode ierr;
3102 
3103   PetscFunctionBegin;
3104   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3105   PetscValidHeaderSpecific(y,VEC_CLASSID,3);
3106   PetscValidHeaderSpecific(q,VEC_CLASSID,4);
3107 
3108   ierr = PetscLogEventBegin(TS_FunctionEval,ts,y,q,0);CHKERRQ(ierr);
3109   if (ts->costintegrand) {
3110     PetscStackPush("TS user integrand in the cost function");
3111     ierr = (*ts->costintegrand)(ts,t,y,q,ts->costintegrandctx);CHKERRQ(ierr);
3112     PetscStackPop;
3113   } else {
3114     ierr = VecZeroEntries(q);CHKERRQ(ierr);
3115   }
3116 
3117   ierr = PetscLogEventEnd(TS_FunctionEval,ts,y,q,0);CHKERRQ(ierr);
3118   PetscFunctionReturn(0);
3119 }
3120 
3121 #undef __FUNCT__
3122 #define __FUNCT__ "TSAdjointComputeDRDYFunction"
3123 /*@
3124   TSAdjointComputeDRDYFunction - Runs the user-defined DRDY function.
3125 
3126   Collective on TS
3127 
3128   Input Parameters:
3129 . ts   - The TS context obtained from TSCreate()
3130 
3131   Notes:
3132   TSAdjointComputeDRDYFunction() is typically used for sensitivity implementation,
3133   so most users would not generally call this routine themselves.
3134 
3135   Level: developer
3136 
3137 .keywords: TS, sensitivity
3138 .seealso: TSAdjointComputeDRDYFunction()
3139 @*/
3140 PetscErrorCode  TSAdjointComputeDRDYFunction(TS ts,PetscReal t,Vec y,Vec *drdy)
3141 {
3142   PetscErrorCode ierr;
3143 
3144   PetscFunctionBegin;
3145   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3146   PetscValidHeaderSpecific(y,VEC_CLASSID,3);
3147 
3148   PetscStackPush("TS user DRDY function for sensitivity analysis");
3149   ierr = (*ts->drdyfunction)(ts,t,y,drdy,ts->costintegrandctx); CHKERRQ(ierr);
3150   PetscStackPop;
3151   PetscFunctionReturn(0);
3152 }
3153 
3154 #undef __FUNCT__
3155 #define __FUNCT__ "TSAdjointComputeDRDPFunction"
3156 /*@
3157   TSAdjointComputeDRDPFunction - Runs the user-defined DRDP function.
3158 
3159   Collective on TS
3160 
3161   Input Parameters:
3162 . ts   - The TS context obtained from TSCreate()
3163 
3164   Notes:
3165   TSDRDPFunction() is typically used for sensitivity implementation,
3166   so most users would not generally call this routine themselves.
3167 
3168   Level: developer
3169 
3170 .keywords: TS, sensitivity
3171 .seealso: TSAdjointSetDRDPFunction()
3172 @*/
3173 PetscErrorCode  TSAdjointComputeDRDPFunction(TS ts,PetscReal t,Vec y,Vec *drdp)
3174 {
3175   PetscErrorCode ierr;
3176 
3177   PetscFunctionBegin;
3178   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3179   PetscValidHeaderSpecific(y,VEC_CLASSID,3);
3180 
3181   PetscStackPush("TS user DRDP function for sensitivity analysis");
3182   ierr = (*ts->drdpfunction)(ts,t,y,drdp,ts->costintegrandctx); CHKERRQ(ierr);
3183   PetscStackPop;
3184   PetscFunctionReturn(0);
3185 }
3186 
3187 #undef __FUNCT__
3188 #define __FUNCT__ "TSSetPreStep"
3189 /*@C
3190   TSSetPreStep - Sets the general-purpose function
3191   called once at the beginning of each time step.
3192 
3193   Logically Collective on TS
3194 
3195   Input Parameters:
3196 + ts   - The TS context obtained from TSCreate()
3197 - func - The function
3198 
3199   Calling sequence of func:
3200 . func (TS ts);
3201 
3202   Level: intermediate
3203 
3204   Note:
3205   If a step is rejected, TSStep() will call this routine again before each attempt.
3206   The last completed time step number can be queried using TSGetTimeStepNumber(), the
3207   size of the step being attempted can be obtained using TSGetTimeStep().
3208 
3209 .keywords: TS, timestep
3210 .seealso: TSSetPreStage(), TSSetPostStage(), TSSetPostStep(), TSStep()
3211 @*/
3212 PetscErrorCode  TSSetPreStep(TS ts, PetscErrorCode (*func)(TS))
3213 {
3214   PetscFunctionBegin;
3215   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3216   ts->prestep = func;
3217   PetscFunctionReturn(0);
3218 }
3219 
3220 #undef __FUNCT__
3221 #define __FUNCT__ "TSPreStep"
3222 /*@
3223   TSPreStep - Runs the user-defined pre-step function.
3224 
3225   Collective on TS
3226 
3227   Input Parameters:
3228 . ts   - The TS context obtained from TSCreate()
3229 
3230   Notes:
3231   TSPreStep() is typically used within time stepping implementations,
3232   so most users would not generally call this routine themselves.
3233 
3234   Level: developer
3235 
3236 .keywords: TS, timestep
3237 .seealso: TSSetPreStep(), TSPreStage(), TSPostStage(), TSPostStep()
3238 @*/
3239 PetscErrorCode  TSPreStep(TS ts)
3240 {
3241   PetscErrorCode ierr;
3242 
3243   PetscFunctionBegin;
3244   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3245   if (ts->prestep) {
3246     PetscStackCallStandard((*ts->prestep),(ts));
3247   }
3248   PetscFunctionReturn(0);
3249 }
3250 
3251 #undef __FUNCT__
3252 #define __FUNCT__ "TSSetPreStage"
3253 /*@C
3254   TSSetPreStage - Sets the general-purpose function
3255   called once at the beginning of each stage.
3256 
3257   Logically Collective on TS
3258 
3259   Input Parameters:
3260 + ts   - The TS context obtained from TSCreate()
3261 - func - The function
3262 
3263   Calling sequence of func:
3264 . PetscErrorCode func(TS ts, PetscReal stagetime);
3265 
3266   Level: intermediate
3267 
3268   Note:
3269   There may be several stages per time step. If the solve for a given stage fails, the step may be rejected and retried.
3270   The time step number being computed can be queried using TSGetTimeStepNumber() and the total size of the step being
3271   attempted can be obtained using TSGetTimeStep(). The time at the start of the step is available via TSGetTime().
3272 
3273 .keywords: TS, timestep
3274 .seealso: TSSetPostStage(), TSSetPreStep(), TSSetPostStep(), TSGetApplicationContext()
3275 @*/
3276 PetscErrorCode  TSSetPreStage(TS ts, PetscErrorCode (*func)(TS,PetscReal))
3277 {
3278   PetscFunctionBegin;
3279   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3280   ts->prestage = func;
3281   PetscFunctionReturn(0);
3282 }
3283 
3284 #undef __FUNCT__
3285 #define __FUNCT__ "TSSetPostStage"
3286 /*@C
3287   TSSetPostStage - Sets the general-purpose function
3288   called once at the end of each stage.
3289 
3290   Logically Collective on TS
3291 
3292   Input Parameters:
3293 + ts   - The TS context obtained from TSCreate()
3294 - func - The function
3295 
3296   Calling sequence of func:
3297 . PetscErrorCode func(TS ts, PetscReal stagetime, PetscInt stageindex, Vec* Y);
3298 
3299   Level: intermediate
3300 
3301   Note:
3302   There may be several stages per time step. If the solve for a given stage fails, the step may be rejected and retried.
3303   The time step number being computed can be queried using TSGetTimeStepNumber() and the total size of the step being
3304   attempted can be obtained using TSGetTimeStep(). The time at the start of the step is available via TSGetTime().
3305 
3306 .keywords: TS, timestep
3307 .seealso: TSSetPreStage(), TSSetPreStep(), TSSetPostStep(), TSGetApplicationContext()
3308 @*/
3309 PetscErrorCode  TSSetPostStage(TS ts, PetscErrorCode (*func)(TS,PetscReal,PetscInt,Vec*))
3310 {
3311   PetscFunctionBegin;
3312   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3313   ts->poststage = func;
3314   PetscFunctionReturn(0);
3315 }
3316 
3317 #undef __FUNCT__
3318 #define __FUNCT__ "TSSetPostEvaluate"
3319 /*@C
3320   TSSetPostEvaluate - Sets the general-purpose function
3321   called once at the end of each step evaluation.
3322 
3323   Logically Collective on TS
3324 
3325   Input Parameters:
3326 + ts   - The TS context obtained from TSCreate()
3327 - func - The function
3328 
3329   Calling sequence of func:
3330 . PetscErrorCode func(TS ts);
3331 
3332   Level: intermediate
3333 
3334   Note:
3335   Semantically, TSSetPostEvaluate() differs from TSSetPostStep() since the function it sets is called before event-handling
3336   thus guaranteeing the same solution (computed by the time-stepper) will be passed to it. On the other hand, TSPostStep()
3337   may be passed a different solution, possibly changed by the event handler. TSPostEvaluate() is called after the next step
3338   solution is evaluated allowing to modify it, if need be. The solution can be obtained with TSGetSolution(), the time step
3339   with TSGetTimeStep(), and the time at the start of the step is available via TSGetTime()
3340 
3341 .keywords: TS, timestep
3342 .seealso: TSSetPreStage(), TSSetPreStep(), TSSetPostStep(), TSGetApplicationContext()
3343 @*/
3344 PetscErrorCode  TSSetPostEvaluate(TS ts, PetscErrorCode (*func)(TS))
3345 {
3346   PetscFunctionBegin;
3347   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3348   ts->postevaluate = func;
3349   PetscFunctionReturn(0);
3350 }
3351 
3352 #undef __FUNCT__
3353 #define __FUNCT__ "TSPreStage"
3354 /*@
3355   TSPreStage - Runs the user-defined pre-stage function set using TSSetPreStage()
3356 
3357   Collective on TS
3358 
3359   Input Parameters:
3360 . ts          - The TS context obtained from TSCreate()
3361   stagetime   - The absolute time of the current stage
3362 
3363   Notes:
3364   TSPreStage() is typically used within time stepping implementations,
3365   most users would not generally call this routine themselves.
3366 
3367   Level: developer
3368 
3369 .keywords: TS, timestep
3370 .seealso: TSPostStage(), TSSetPreStep(), TSPreStep(), TSPostStep()
3371 @*/
3372 PetscErrorCode  TSPreStage(TS ts, PetscReal stagetime)
3373 {
3374   PetscErrorCode ierr;
3375 
3376   PetscFunctionBegin;
3377   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3378   if (ts->prestage) {
3379     PetscStackCallStandard((*ts->prestage),(ts,stagetime));
3380   }
3381   PetscFunctionReturn(0);
3382 }
3383 
3384 #undef __FUNCT__
3385 #define __FUNCT__ "TSPostStage"
3386 /*@
3387   TSPostStage - Runs the user-defined post-stage function set using TSSetPostStage()
3388 
3389   Collective on TS
3390 
3391   Input Parameters:
3392 . ts          - The TS context obtained from TSCreate()
3393   stagetime   - The absolute time of the current stage
3394   stageindex  - Stage number
3395   Y           - Array of vectors (of size = total number
3396                 of stages) with the stage solutions
3397 
3398   Notes:
3399   TSPostStage() is typically used within time stepping implementations,
3400   most users would not generally call this routine themselves.
3401 
3402   Level: developer
3403 
3404 .keywords: TS, timestep
3405 .seealso: TSPreStage(), TSSetPreStep(), TSPreStep(), TSPostStep()
3406 @*/
3407 PetscErrorCode  TSPostStage(TS ts, PetscReal stagetime, PetscInt stageindex, Vec *Y)
3408 {
3409   PetscErrorCode ierr;
3410 
3411   PetscFunctionBegin;
3412   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3413   if (ts->poststage) {
3414     PetscStackCallStandard((*ts->poststage),(ts,stagetime,stageindex,Y));
3415   }
3416   PetscFunctionReturn(0);
3417 }
3418 
3419 #undef __FUNCT__
3420 #define __FUNCT__ "TSPostEvaluate"
3421 /*@
3422   TSPostEvaluate - Runs the user-defined post-evaluate function set using TSSetPostEvaluate()
3423 
3424   Collective on TS
3425 
3426   Input Parameters:
3427 . ts          - The TS context obtained from TSCreate()
3428 
3429   Notes:
3430   TSPostEvaluate() is typically used within time stepping implementations,
3431   most users would not generally call this routine themselves.
3432 
3433   Level: developer
3434 
3435 .keywords: TS, timestep
3436 .seealso: TSSetPostEvaluate(), TSSetPreStep(), TSPreStep(), TSPostStep()
3437 @*/
3438 PetscErrorCode  TSPostEvaluate(TS ts)
3439 {
3440   PetscErrorCode ierr;
3441 
3442   PetscFunctionBegin;
3443   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3444   if (ts->postevaluate) {
3445     PetscStackCallStandard((*ts->postevaluate),(ts));
3446   }
3447   PetscFunctionReturn(0);
3448 }
3449 
3450 #undef __FUNCT__
3451 #define __FUNCT__ "TSSetPostStep"
3452 /*@C
3453   TSSetPostStep - Sets the general-purpose function
3454   called once at the end of each time step.
3455 
3456   Logically Collective on TS
3457 
3458   Input Parameters:
3459 + ts   - The TS context obtained from TSCreate()
3460 - func - The function
3461 
3462   Calling sequence of func:
3463 $ func (TS ts);
3464 
3465   Notes:
3466   The function set by TSSetPostStep() is called after each successful step. The solution vector X
3467   obtained by TSGetSolution() may be different than that computed at the step end if the event handler
3468   locates an event and TSPostEvent() modifies it. Use TSSetPostEvaluate() if an unmodified solution is needed instead.
3469 
3470   Level: intermediate
3471 
3472 .keywords: TS, timestep
3473 .seealso: TSSetPreStep(), TSSetPreStage(), TSSetPostEvaluate(), TSGetTimeStep(), TSGetTimeStepNumber(), TSGetTime()
3474 @*/
3475 PetscErrorCode  TSSetPostStep(TS ts, PetscErrorCode (*func)(TS))
3476 {
3477   PetscFunctionBegin;
3478   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3479   ts->poststep = func;
3480   PetscFunctionReturn(0);
3481 }
3482 
3483 #undef __FUNCT__
3484 #define __FUNCT__ "TSPostStep"
3485 /*@
3486   TSPostStep - Runs the user-defined post-step function.
3487 
3488   Collective on TS
3489 
3490   Input Parameters:
3491 . ts   - The TS context obtained from TSCreate()
3492 
3493   Notes:
3494   TSPostStep() is typically used within time stepping implementations,
3495   so most users would not generally call this routine themselves.
3496 
3497   Level: developer
3498 
3499 .keywords: TS, timestep
3500 @*/
3501 PetscErrorCode  TSPostStep(TS ts)
3502 {
3503   PetscErrorCode ierr;
3504 
3505   PetscFunctionBegin;
3506   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3507   if (ts->poststep) {
3508     PetscStackCallStandard((*ts->poststep),(ts));
3509   }
3510   PetscFunctionReturn(0);
3511 }
3512 
3513 /* ------------ Routines to set performance monitoring options ----------- */
3514 
3515 #undef __FUNCT__
3516 #define __FUNCT__ "TSMonitorSet"
3517 /*@C
3518    TSMonitorSet - Sets an ADDITIONAL function that is to be used at every
3519    timestep to display the iteration's  progress.
3520 
3521    Logically Collective on TS
3522 
3523    Input Parameters:
3524 +  ts - the TS context obtained from TSCreate()
3525 .  monitor - monitoring routine
3526 .  mctx - [optional] user-defined context for private data for the
3527              monitor routine (use NULL if no context is desired)
3528 -  monitordestroy - [optional] routine that frees monitor context
3529           (may be NULL)
3530 
3531    Calling sequence of monitor:
3532 $    int monitor(TS ts,PetscInt steps,PetscReal time,Vec u,void *mctx)
3533 
3534 +    ts - the TS context
3535 .    steps - iteration number (after the final time step the monitor routine may be called with a step of -1, this indicates the solution has been interpolated to this time)
3536 .    time - current time
3537 .    u - current iterate
3538 -    mctx - [optional] monitoring context
3539 
3540    Notes:
3541    This routine adds an additional monitor to the list of monitors that
3542    already has been loaded.
3543 
3544    Fortran notes: Only a single monitor function can be set for each TS object
3545 
3546    Level: intermediate
3547 
3548 .keywords: TS, timestep, set, monitor
3549 
3550 .seealso: TSMonitorDefault(), TSMonitorCancel()
3551 @*/
3552 PetscErrorCode  TSMonitorSet(TS ts,PetscErrorCode (*monitor)(TS,PetscInt,PetscReal,Vec,void*),void *mctx,PetscErrorCode (*mdestroy)(void**))
3553 {
3554   PetscErrorCode ierr;
3555   PetscInt       i;
3556   PetscBool      identical;
3557 
3558   PetscFunctionBegin;
3559   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3560   for (i=0; i<ts->numbermonitors;i++) {
3561     ierr = PetscMonitorCompare((PetscErrorCode (*)(void))monitor,mctx,mdestroy,(PetscErrorCode (*)(void))ts->monitor[i],ts->monitorcontext[i],ts->monitordestroy[i],&identical);CHKERRQ(ierr);
3562     if (identical) PetscFunctionReturn(0);
3563   }
3564   if (ts->numbermonitors >= MAXTSMONITORS) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Too many monitors set");
3565   ts->monitor[ts->numbermonitors]          = monitor;
3566   ts->monitordestroy[ts->numbermonitors]   = mdestroy;
3567   ts->monitorcontext[ts->numbermonitors++] = (void*)mctx;
3568   PetscFunctionReturn(0);
3569 }
3570 
3571 #undef __FUNCT__
3572 #define __FUNCT__ "TSMonitorCancel"
3573 /*@C
3574    TSMonitorCancel - Clears all the monitors that have been set on a time-step object.
3575 
3576    Logically Collective on TS
3577 
3578    Input Parameters:
3579 .  ts - the TS context obtained from TSCreate()
3580 
3581    Notes:
3582    There is no way to remove a single, specific monitor.
3583 
3584    Level: intermediate
3585 
3586 .keywords: TS, timestep, set, monitor
3587 
3588 .seealso: TSMonitorDefault(), TSMonitorSet()
3589 @*/
3590 PetscErrorCode  TSMonitorCancel(TS ts)
3591 {
3592   PetscErrorCode ierr;
3593   PetscInt       i;
3594 
3595   PetscFunctionBegin;
3596   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3597   for (i=0; i<ts->numbermonitors; i++) {
3598     if (ts->monitordestroy[i]) {
3599       ierr = (*ts->monitordestroy[i])(&ts->monitorcontext[i]);CHKERRQ(ierr);
3600     }
3601   }
3602   ts->numbermonitors = 0;
3603   PetscFunctionReturn(0);
3604 }
3605 
3606 #undef __FUNCT__
3607 #define __FUNCT__ "TSMonitorDefault"
3608 /*@C
3609    TSMonitorDefault - The Default monitor, prints the timestep and time for each step
3610 
3611    Level: intermediate
3612 
3613 .keywords: TS, set, monitor
3614 
3615 .seealso:  TSMonitorSet()
3616 @*/
3617 PetscErrorCode TSMonitorDefault(TS ts,PetscInt step,PetscReal ptime,Vec v,PetscViewerAndFormat *vf)
3618 {
3619   PetscErrorCode ierr;
3620   PetscViewer    viewer =  vf->viewer;
3621   PetscBool      iascii,ibinary;
3622 
3623   PetscFunctionBegin;
3624   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,4);
3625   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
3626   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&ibinary);CHKERRQ(ierr);
3627   ierr = PetscViewerPushFormat(viewer,vf->format);CHKERRQ(ierr);
3628   if (iascii) {
3629     ierr = PetscViewerASCIIAddTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
3630     if (step == -1){ /* this indicates it is an interpolated solution */
3631       ierr = PetscViewerASCIIPrintf(viewer,"Interpolated solution at time %g between steps %D and %D\n",(double)ptime,ts->steps-1,ts->steps);CHKERRQ(ierr);
3632     } else {
3633       ierr = PetscViewerASCIIPrintf(viewer,"%D TS dt %g time %g%s",step,(double)ts->time_step,(double)ptime,ts->steprollback ? " (r)\n" : "\n");CHKERRQ(ierr);
3634     }
3635     ierr = PetscViewerASCIISubtractTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
3636   } else if (ibinary) {
3637     PetscMPIInt rank;
3638     ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)viewer),&rank);CHKERRQ(ierr);
3639     if (!rank) {
3640       PetscBool skipHeader;
3641       PetscInt  classid = REAL_FILE_CLASSID;
3642 
3643       ierr = PetscViewerBinaryGetSkipHeader(viewer,&skipHeader);CHKERRQ(ierr);
3644       if (!skipHeader) {
3645          ierr = PetscViewerBinaryWrite(viewer,&classid,1,PETSC_INT,PETSC_FALSE);CHKERRQ(ierr);
3646        }
3647       ierr = PetscRealView(1,&ptime,viewer);CHKERRQ(ierr);
3648     } else {
3649       ierr = PetscRealView(0,&ptime,viewer);CHKERRQ(ierr);
3650     }
3651   }
3652   ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
3653   PetscFunctionReturn(0);
3654 }
3655 
3656 #undef __FUNCT__
3657 #define __FUNCT__ "TSAdjointMonitorSet"
3658 /*@C
3659    TSAdjointMonitorSet - Sets an ADDITIONAL function that is to be used at every
3660    timestep to display the iteration's  progress.
3661 
3662    Logically Collective on TS
3663 
3664    Input Parameters:
3665 +  ts - the TS context obtained from TSCreate()
3666 .  adjointmonitor - monitoring routine
3667 .  adjointmctx - [optional] user-defined context for private data for the
3668              monitor routine (use NULL if no context is desired)
3669 -  adjointmonitordestroy - [optional] routine that frees monitor context
3670           (may be NULL)
3671 
3672    Calling sequence of monitor:
3673 $    int adjointmonitor(TS ts,PetscInt steps,PetscReal time,Vec u,PetscInt numcost,Vec *lambda, Vec *mu,void *adjointmctx)
3674 
3675 +    ts - the TS context
3676 .    steps - iteration number (after the final time step the monitor routine is called with a step of -1, this is at the final time which may have
3677                                been interpolated to)
3678 .    time - current time
3679 .    u - current iterate
3680 .    numcost - number of cost functionos
3681 .    lambda - sensitivities to initial conditions
3682 .    mu - sensitivities to parameters
3683 -    adjointmctx - [optional] adjoint monitoring context
3684 
3685    Notes:
3686    This routine adds an additional monitor to the list of monitors that
3687    already has been loaded.
3688 
3689    Fortran notes: Only a single monitor function can be set for each TS object
3690 
3691    Level: intermediate
3692 
3693 .keywords: TS, timestep, set, adjoint, monitor
3694 
3695 .seealso: TSAdjointMonitorCancel()
3696 @*/
3697 PetscErrorCode  TSAdjointMonitorSet(TS ts,PetscErrorCode (*adjointmonitor)(TS,PetscInt,PetscReal,Vec,PetscInt,Vec*,Vec*,void*),void *adjointmctx,PetscErrorCode (*adjointmdestroy)(void**))
3698 {
3699   PetscErrorCode ierr;
3700   PetscInt       i;
3701   PetscBool      identical;
3702 
3703   PetscFunctionBegin;
3704   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3705   for (i=0; i<ts->numbermonitors;i++) {
3706     ierr = PetscMonitorCompare((PetscErrorCode (*)(void))adjointmonitor,adjointmctx,adjointmdestroy,(PetscErrorCode (*)(void))ts->adjointmonitor[i],ts->adjointmonitorcontext[i],ts->adjointmonitordestroy[i],&identical);CHKERRQ(ierr);
3707     if (identical) PetscFunctionReturn(0);
3708   }
3709   if (ts->numberadjointmonitors >= MAXTSMONITORS) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Too many adjoint monitors set");
3710   ts->adjointmonitor[ts->numberadjointmonitors]          = adjointmonitor;
3711   ts->adjointmonitordestroy[ts->numberadjointmonitors]   = adjointmdestroy;
3712   ts->adjointmonitorcontext[ts->numberadjointmonitors++] = (void*)adjointmctx;
3713   PetscFunctionReturn(0);
3714 }
3715 
3716 #undef __FUNCT__
3717 #define __FUNCT__ "TSAdjointMonitorCancel"
3718 /*@C
3719    TSAdjointMonitorCancel - Clears all the adjoint monitors that have been set on a time-step object.
3720 
3721    Logically Collective on TS
3722 
3723    Input Parameters:
3724 .  ts - the TS context obtained from TSCreate()
3725 
3726    Notes:
3727    There is no way to remove a single, specific monitor.
3728 
3729    Level: intermediate
3730 
3731 .keywords: TS, timestep, set, adjoint, monitor
3732 
3733 .seealso: TSAdjointMonitorSet()
3734 @*/
3735 PetscErrorCode  TSAdjointMonitorCancel(TS ts)
3736 {
3737   PetscErrorCode ierr;
3738   PetscInt       i;
3739 
3740   PetscFunctionBegin;
3741   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3742   for (i=0; i<ts->numberadjointmonitors; i++) {
3743     if (ts->adjointmonitordestroy[i]) {
3744       ierr = (*ts->adjointmonitordestroy[i])(&ts->adjointmonitorcontext[i]);CHKERRQ(ierr);
3745     }
3746   }
3747   ts->numberadjointmonitors = 0;
3748   PetscFunctionReturn(0);
3749 }
3750 
3751 #undef __FUNCT__
3752 #define __FUNCT__ "TSAdjointMonitorDefault"
3753 /*@C
3754    TSAdjointMonitorDefault - the default monitor of adjoint computations
3755 
3756    Level: intermediate
3757 
3758 .keywords: TS, set, monitor
3759 
3760 .seealso: TSAdjointMonitorSet()
3761 @*/
3762 PetscErrorCode TSAdjointMonitorDefault(TS ts,PetscInt step,PetscReal ptime,Vec v,PetscInt numcost,Vec *lambda,Vec *mu,PetscViewerAndFormat *vf)
3763 {
3764   PetscErrorCode ierr;
3765   PetscViewer    viewer = vf->viewer;
3766 
3767   PetscFunctionBegin;
3768   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,4);
3769   ierr = PetscViewerPushFormat(viewer,vf->format);CHKERRQ(ierr);
3770   ierr = PetscViewerASCIIAddTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
3771   ierr = PetscViewerASCIIPrintf(viewer,"%D TS dt %g time %g%s",step,(double)ts->time_step,(double)ptime,ts->steprollback ? " (r)\n" : "\n");CHKERRQ(ierr);
3772   ierr = PetscViewerASCIISubtractTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
3773   ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
3774   PetscFunctionReturn(0);
3775 }
3776 
3777 #undef __FUNCT__
3778 #define __FUNCT__ "TSInterpolate"
3779 /*@
3780    TSInterpolate - Interpolate the solution computed during the previous step to an arbitrary location in the interval
3781 
3782    Collective on TS
3783 
3784    Input Argument:
3785 +  ts - time stepping context
3786 -  t - time to interpolate to
3787 
3788    Output Argument:
3789 .  U - state at given time
3790 
3791    Level: intermediate
3792 
3793    Developer Notes:
3794    TSInterpolate() and the storing of previous steps/stages should be generalized to support delay differential equations and continuous adjoints.
3795 
3796 .keywords: TS, set
3797 
3798 .seealso: TSSetExactFinalTime(), TSSolve()
3799 @*/
3800 PetscErrorCode TSInterpolate(TS ts,PetscReal t,Vec U)
3801 {
3802   PetscErrorCode ierr;
3803 
3804   PetscFunctionBegin;
3805   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3806   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
3807   if (t < ts->ptime_prev || t > ts->ptime) SETERRQ3(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_OUTOFRANGE,"Requested time %g not in last time steps [%g,%g]",t,(double)ts->ptime_prev,(double)ts->ptime);
3808   if (!ts->ops->interpolate) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"%s does not provide interpolation",((PetscObject)ts)->type_name);
3809   ierr = (*ts->ops->interpolate)(ts,t,U);CHKERRQ(ierr);
3810   PetscFunctionReturn(0);
3811 }
3812 
3813 #undef __FUNCT__
3814 #define __FUNCT__ "TSStep"
3815 /*@
3816    TSStep - Steps one time step
3817 
3818    Collective on TS
3819 
3820    Input Parameter:
3821 .  ts - the TS context obtained from TSCreate()
3822 
3823    Level: developer
3824 
3825    Notes:
3826    The public interface for the ODE/DAE solvers is TSSolve(), you should almost for sure be using that routine and not this routine.
3827 
3828    The hook set using TSSetPreStep() is called before each attempt to take the step. In general, the time step size may
3829    be changed due to adaptive error controller or solve failures. Note that steps may contain multiple stages.
3830 
3831    This may over-step the final time provided in TSSetDuration() depending on the time-step used. TSSolve() interpolates to exactly the
3832    time provided in TSSetDuration(). One can use TSInterpolate() to determine an interpolated solution within the final timestep.
3833 
3834 .keywords: TS, timestep, solve
3835 
3836 .seealso: TSCreate(), TSSetUp(), TSDestroy(), TSSolve(), TSSetPreStep(), TSSetPreStage(), TSSetPostStage(), TSInterpolate()
3837 @*/
3838 PetscErrorCode  TSStep(TS ts)
3839 {
3840   PetscErrorCode   ierr;
3841   static PetscBool cite = PETSC_FALSE;
3842   PetscReal        ptime;
3843 
3844   PetscFunctionBegin;
3845   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3846   ierr = PetscCitationsRegister("@techreport{tspaper,\n"
3847                                 "  title       = {{PETSc/TS}: A Modern Scalable {DAE/ODE} Solver Library},\n"
3848                                 "  author      = {Shrirang Abhyankar and Jed Brown and Emil Constantinescu and Debojyoti Ghosh and Barry F. Smith},\n"
3849                                 "  type        = {Preprint},\n"
3850                                 "  number      = {ANL/MCS-P5061-0114},\n"
3851                                 "  institution = {Argonne National Laboratory},\n"
3852                                 "  year        = {2014}\n}\n",&cite);CHKERRQ(ierr);
3853 
3854   ierr = TSSetUp(ts);CHKERRQ(ierr);
3855   ierr = TSTrajectorySetUp(ts->trajectory,ts);CHKERRQ(ierr);
3856 
3857   if (ts->exact_final_time == TS_EXACTFINALTIME_UNSPECIFIED) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONGSTATE,"You must call TSSetExactFinalTime() or use -ts_exact_final_time <stepover,interpolate,matchstep> before calling TSStep()");
3858   if (ts->exact_final_time == TS_EXACTFINALTIME_MATCHSTEP && !ts->adapt) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Since TS is not adaptive you cannot use TS_EXACTFINALTIME_MATCHSTEP, suggest TS_EXACTFINALTIME_INTERPOLATE");
3859 
3860   if (!ts->steps) ts->ptime_prev = ts->ptime;
3861   ts->reason = TS_CONVERGED_ITERATING;
3862   ptime = ts->ptime; ts->ptime_prev_rollback = ts->ptime_prev;
3863   if (!ts->ops->step) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSStep not implemented for type '%s'",((PetscObject)ts)->type_name);
3864   ierr = PetscLogEventBegin(TS_Step,ts,0,0,0);CHKERRQ(ierr);
3865   ierr = (*ts->ops->step)(ts);CHKERRQ(ierr);
3866   ierr = PetscLogEventEnd(TS_Step,ts,0,0,0);CHKERRQ(ierr);
3867   ts->ptime_prev = ptime;
3868   ts->steps++; ts->total_steps++;
3869   ts->steprollback = PETSC_FALSE;
3870   ts->steprestart  = PETSC_FALSE;
3871 
3872   if (ts->reason < 0) {
3873     if (ts->errorifstepfailed) {
3874       if (ts->reason == TS_DIVERGED_NONLINEAR_SOLVE) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_NOT_CONVERGED,"TSStep has failed due to %s, increase -ts_max_snes_failures or make negative to attempt recovery",TSConvergedReasons[ts->reason]);
3875       else SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_NOT_CONVERGED,"TSStep has failed due to %s",TSConvergedReasons[ts->reason]);
3876     }
3877   } else if (!ts->reason) {
3878     if (ts->steps >= ts->max_steps)     ts->reason = TS_CONVERGED_ITS;
3879     else if (ts->ptime >= ts->max_time) ts->reason = TS_CONVERGED_TIME;
3880   }
3881   PetscFunctionReturn(0);
3882 }
3883 
3884 #undef __FUNCT__
3885 #define __FUNCT__ "TSAdjointStep"
3886 /*@
3887    TSAdjointStep - Steps one time step backward in the adjoint run
3888 
3889    Collective on TS
3890 
3891    Input Parameter:
3892 .  ts - the TS context obtained from TSCreate()
3893 
3894    Level: intermediate
3895 
3896 .keywords: TS, adjoint, step
3897 
3898 .seealso: TSAdjointSetUp(), TSAdjointSolve()
3899 @*/
3900 PetscErrorCode  TSAdjointStep(TS ts)
3901 {
3902   DM               dm;
3903   PetscErrorCode   ierr;
3904 
3905   PetscFunctionBegin;
3906   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3907   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
3908   ierr = TSAdjointSetUp(ts);CHKERRQ(ierr);
3909 
3910   ierr = VecViewFromOptions(ts->vec_sol,(PetscObject)ts,"-ts_view_solution");CHKERRQ(ierr);
3911 
3912   ts->reason = TS_CONVERGED_ITERATING;
3913   ts->ptime_prev = ts->ptime;
3914   if (!ts->ops->adjointstep) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_NOT_CONVERGED,"TSStep has failed because the adjoint of  %s has not been implemented, try other time stepping methods for adjoint sensitivity analysis",((PetscObject)ts)->type_name);
3915   ierr = PetscLogEventBegin(TS_AdjointStep,ts,0,0,0);CHKERRQ(ierr);
3916   ierr = (*ts->ops->adjointstep)(ts);CHKERRQ(ierr);
3917   ierr = PetscLogEventEnd(TS_AdjointStep,ts,0,0,0);CHKERRQ(ierr);
3918   ts->steps++; ts->total_steps--;
3919 
3920   if (ts->reason < 0) {
3921     if (ts->errorifstepfailed) {
3922       if (ts->reason == TS_DIVERGED_NONLINEAR_SOLVE) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_NOT_CONVERGED,"TSStep has failed due to %s, increase -ts_max_snes_failures or make negative to attempt recovery",TSConvergedReasons[ts->reason]);
3923       else if (ts->reason == TS_DIVERGED_STEP_REJECTED) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_NOT_CONVERGED,"TSStep has failed due to %s, increase -ts_max_reject or make negative to attempt recovery",TSConvergedReasons[ts->reason]);
3924       else SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_NOT_CONVERGED,"TSStep has failed due to %s",TSConvergedReasons[ts->reason]);
3925     }
3926   } else if (!ts->reason) {
3927     if (ts->steps >= ts->adjoint_max_steps) ts->reason = TS_CONVERGED_ITS;
3928   }
3929   PetscFunctionReturn(0);
3930 }
3931 
3932 #undef __FUNCT__
3933 #define __FUNCT__ "TSEvaluateWLTE"
3934 /*@
3935    TSEvaluateWLTE - Evaluate the weighted local truncation error norm
3936    at the end of a time step with a given order of accuracy.
3937 
3938    Collective on TS
3939 
3940    Input Arguments:
3941 +  ts - time stepping context
3942 .  wnormtype - norm type, either NORM_2 or NORM_INFINITY
3943 -  order - optional, desired order for the error evaluation or PETSC_DECIDE
3944 
3945    Output Arguments:
3946 +  order - optional, the actual order of the error evaluation
3947 -  wlte - the weighted local truncation error norm
3948 
3949    Level: advanced
3950 
3951    Notes:
3952    If the timestepper cannot evaluate the error in a particular step
3953    (eg. in the first step or restart steps after event handling),
3954    this routine returns wlte=-1.0 .
3955 
3956 .seealso: TSStep(), TSAdapt, TSErrorWeightedNorm()
3957 @*/
3958 PetscErrorCode TSEvaluateWLTE(TS ts,NormType wnormtype,PetscInt *order,PetscReal *wlte)
3959 {
3960   PetscErrorCode ierr;
3961 
3962   PetscFunctionBegin;
3963   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3964   PetscValidType(ts,1);
3965   PetscValidLogicalCollectiveEnum(ts,wnormtype,4);
3966   if (order) PetscValidIntPointer(order,3);
3967   if (order) PetscValidLogicalCollectiveInt(ts,*order,3);
3968   PetscValidRealPointer(wlte,4);
3969   if (wnormtype != NORM_2 && wnormtype != NORM_INFINITY) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"No support for norm type %s",NormTypes[wnormtype]);
3970   if (!ts->ops->evaluatewlte) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSEvaluateWLTE not implemented for type '%s'",((PetscObject)ts)->type_name);
3971   ierr = (*ts->ops->evaluatewlte)(ts,wnormtype,order,wlte);CHKERRQ(ierr);
3972   PetscFunctionReturn(0);
3973 }
3974 
3975 #undef __FUNCT__
3976 #define __FUNCT__ "TSEvaluateStep"
3977 /*@
3978    TSEvaluateStep - Evaluate the solution at the end of a time step with a given order of accuracy.
3979 
3980    Collective on TS
3981 
3982    Input Arguments:
3983 +  ts - time stepping context
3984 .  order - desired order of accuracy
3985 -  done - whether the step was evaluated at this order (pass NULL to generate an error if not available)
3986 
3987    Output Arguments:
3988 .  U - state at the end of the current step
3989 
3990    Level: advanced
3991 
3992    Notes:
3993    This function cannot be called until all stages have been evaluated.
3994    It is normally called by adaptive controllers before a step has been accepted and may also be called by the user after TSStep() has returned.
3995 
3996 .seealso: TSStep(), TSAdapt
3997 @*/
3998 PetscErrorCode TSEvaluateStep(TS ts,PetscInt order,Vec U,PetscBool *done)
3999 {
4000   PetscErrorCode ierr;
4001 
4002   PetscFunctionBegin;
4003   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4004   PetscValidType(ts,1);
4005   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
4006   if (!ts->ops->evaluatestep) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSEvaluateStep not implemented for type '%s'",((PetscObject)ts)->type_name);
4007   ierr = (*ts->ops->evaluatestep)(ts,order,U,done);CHKERRQ(ierr);
4008   PetscFunctionReturn(0);
4009 }
4010 
4011 #undef __FUNCT__
4012 #define __FUNCT__ "TSForwardCostIntegral"
4013 /*@
4014  TSForwardCostIntegral - Evaluate the cost integral in the forward run.
4015 
4016  Collective on TS
4017 
4018  Input Arguments:
4019  .  ts - time stepping context
4020 
4021  Level: advanced
4022 
4023  Notes:
4024  This function cannot be called until TSStep() has been completed.
4025 
4026  .seealso: TSSolve(), TSAdjointCostIntegral()
4027  @*/
4028 PetscErrorCode TSForwardCostIntegral(TS ts)
4029 {
4030     PetscErrorCode ierr;
4031     PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4032     if (!ts->ops->forwardintegral) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"%s does not provide integral evaluation in the forward run",((PetscObject)ts)->type_name);
4033     ierr = (*ts->ops->forwardintegral)(ts);CHKERRQ(ierr);
4034     PetscFunctionReturn(0);
4035 }
4036 
4037 #undef __FUNCT__
4038 #define __FUNCT__ "TSSolve"
4039 /*@
4040    TSSolve - Steps the requested number of timesteps.
4041 
4042    Collective on TS
4043 
4044    Input Parameter:
4045 +  ts - the TS context obtained from TSCreate()
4046 -  u - the solution vector  (can be null if TSSetSolution() was used and TSSetExactFinalTime(ts,TS_EXACTFINALTIME_MATCHSTEP) was not used,
4047                              otherwise must contain the initial conditions and will contain the solution at the final requested time
4048 
4049    Level: beginner
4050 
4051    Notes:
4052    The final time returned by this function may be different from the time of the internally
4053    held state accessible by TSGetSolution() and TSGetTime() because the method may have
4054    stepped over the final time.
4055 
4056 .keywords: TS, timestep, solve
4057 
4058 .seealso: TSCreate(), TSSetSolution(), TSStep(), TSGetTime(), TSGetSolveTime()
4059 @*/
4060 PetscErrorCode TSSolve(TS ts,Vec u)
4061 {
4062   Vec               solution;
4063   PetscErrorCode    ierr;
4064 
4065   PetscFunctionBegin;
4066   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4067   if (u) PetscValidHeaderSpecific(u,VEC_CLASSID,2);
4068 
4069   if (ts->exact_final_time == TS_EXACTFINALTIME_INTERPOLATE) {   /* Need ts->vec_sol to be distinct so it is not overwritten when we interpolate at the end */
4070     PetscValidHeaderSpecific(u,VEC_CLASSID,2);
4071     if (!ts->vec_sol || u == ts->vec_sol) {
4072       ierr = VecDuplicate(u,&solution);CHKERRQ(ierr);
4073       ierr = TSSetSolution(ts,solution);CHKERRQ(ierr);
4074       ierr = VecDestroy(&solution);CHKERRQ(ierr); /* grant ownership */
4075     }
4076     ierr = VecCopy(u,ts->vec_sol);CHKERRQ(ierr);
4077   } else if (u) {
4078     ierr = TSSetSolution(ts,u);CHKERRQ(ierr);
4079   }
4080   ierr = TSSetUp(ts);CHKERRQ(ierr);
4081   ierr = TSTrajectorySetUp(ts->trajectory,ts);CHKERRQ(ierr);
4082 
4083   if (ts->exact_final_time == TS_EXACTFINALTIME_UNSPECIFIED) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONGSTATE,"You must call TSSetExactFinalTime() or use -ts_exact_final_time <stepover,interpolate,matchstep> before calling TSSolve()");
4084   if (ts->exact_final_time == TS_EXACTFINALTIME_MATCHSTEP && !ts->adapt) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Since TS is not adaptive you cannot use TS_EXACTFINALTIME_MATCHSTEP, suggest TS_EXACTFINALTIME_INTERPOLATE");
4085 
4086   /* reset time step and iteration counters */
4087   ts->steps             = 0;
4088   ts->ksp_its           = 0;
4089   ts->snes_its          = 0;
4090   ts->num_snes_failures = 0;
4091   ts->reject            = 0;
4092   ts->reason            = TS_CONVERGED_ITERATING;
4093 
4094   ierr = TSViewFromOptions(ts,NULL,"-ts_view_pre");CHKERRQ(ierr);
4095 
4096   if (ts->ops->solve) { /* This private interface is transitional and should be removed when all implementations are updated. */
4097     ierr = (*ts->ops->solve)(ts);CHKERRQ(ierr);
4098     if (u) {ierr = VecCopy(ts->vec_sol,u);CHKERRQ(ierr);}
4099     ts->solvetime = ts->ptime;
4100     solution = ts->vec_sol;
4101   } else { /* Step the requested number of timesteps. */
4102     if (ts->steps >= ts->max_steps)     ts->reason = TS_CONVERGED_ITS;
4103     else if (ts->ptime >= ts->max_time) ts->reason = TS_CONVERGED_TIME;
4104     ierr = TSTrajectorySet(ts->trajectory,ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
4105     ierr = TSEventInitialize(ts->event,ts,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
4106     ts->steprollback = PETSC_FALSE;
4107     ts->steprestart  = PETSC_TRUE;
4108 
4109     while (!ts->reason) {
4110       ierr = TSMonitor(ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
4111       if (!ts->steprollback) {
4112         ierr = TSPreStep(ts);CHKERRQ(ierr);
4113       }
4114       ierr = TSStep(ts);CHKERRQ(ierr);
4115       if (ts->vec_costintegral && ts->costintegralfwd) { /* Must evaluate the cost integral before event is handled. The cost integral value can also be rolled back. */
4116         ierr = TSForwardCostIntegral(ts);CHKERRQ(ierr);
4117       }
4118       ierr = TSEventHandler(ts);CHKERRQ(ierr); /* The right-hand side may be changed due to event. Be careful with Any computation using the RHS information after this point. */
4119       if (!ts->steprollback) {
4120         ierr = TSTrajectorySet(ts->trajectory,ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
4121         ierr = TSPostStep(ts);CHKERRQ(ierr);
4122       }
4123     }
4124     ierr = TSMonitor(ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
4125 
4126     if (ts->exact_final_time == TS_EXACTFINALTIME_INTERPOLATE && ts->ptime > ts->max_time) {
4127       ierr = TSInterpolate(ts,ts->max_time,u);CHKERRQ(ierr);
4128       ts->solvetime = ts->max_time;
4129       solution = u;
4130       ierr = TSMonitor(ts,-1,ts->solvetime,solution);CHKERRQ(ierr);
4131     } else {
4132       if (u) {ierr = VecCopy(ts->vec_sol,u);CHKERRQ(ierr);}
4133       ts->solvetime = ts->ptime;
4134       solution = ts->vec_sol;
4135     }
4136   }
4137 
4138   ierr = TSViewFromOptions(ts,NULL,"-ts_view");CHKERRQ(ierr);
4139   ierr = VecViewFromOptions(solution,NULL,"-ts_view_solution");CHKERRQ(ierr);
4140   ierr = PetscObjectSAWsBlock((PetscObject)ts);CHKERRQ(ierr);
4141   if (ts->adjoint_solve) {
4142     ierr = TSAdjointSolve(ts);CHKERRQ(ierr);
4143   }
4144   PetscFunctionReturn(0);
4145 }
4146 
4147 #undef __FUNCT__
4148 #define __FUNCT__ "TSAdjointCostIntegral"
4149 /*@
4150  TSAdjointCostIntegral - Evaluate the cost integral in the adjoint run.
4151 
4152  Collective on TS
4153 
4154  Input Arguments:
4155  .  ts - time stepping context
4156 
4157  Level: advanced
4158 
4159  Notes:
4160  This function cannot be called until TSAdjointStep() has been completed.
4161 
4162  .seealso: TSAdjointSolve(), TSAdjointStep
4163  @*/
4164 PetscErrorCode TSAdjointCostIntegral(TS ts)
4165 {
4166     PetscErrorCode ierr;
4167     PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4168     if (!ts->ops->adjointintegral) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"%s does not provide integral evaluation in the adjoint run",((PetscObject)ts)->type_name);
4169     ierr = (*ts->ops->adjointintegral)(ts);CHKERRQ(ierr);
4170     PetscFunctionReturn(0);
4171 }
4172 
4173 #undef __FUNCT__
4174 #define __FUNCT__ "TSAdjointSolve"
4175 /*@
4176    TSAdjointSolve - Solves the discrete ajoint problem for an ODE/DAE
4177 
4178    Collective on TS
4179 
4180    Input Parameter:
4181 .  ts - the TS context obtained from TSCreate()
4182 
4183    Options Database:
4184 . -ts_adjoint_view_solution <viewerinfo> - views the first gradient with respect to the initial conditions
4185 
4186    Level: intermediate
4187 
4188    Notes:
4189    This must be called after a call to TSSolve() that solves the forward problem
4190 
4191    By default this will integrate back to the initial time, one can use TSAdjointSetSteps() to step back to a later time
4192 
4193 .keywords: TS, timestep, solve
4194 
4195 .seealso: TSCreate(), TSSetCostGradients(), TSSetSolution(), TSAdjointStep()
4196 @*/
4197 PetscErrorCode TSAdjointSolve(TS ts)
4198 {
4199   PetscErrorCode    ierr;
4200 
4201   PetscFunctionBegin;
4202   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4203   ierr = TSAdjointSetUp(ts);CHKERRQ(ierr);
4204 
4205   /* reset time step and iteration counters */
4206   ts->steps             = 0;
4207   ts->ksp_its           = 0;
4208   ts->snes_its          = 0;
4209   ts->num_snes_failures = 0;
4210   ts->reject            = 0;
4211   ts->reason            = TS_CONVERGED_ITERATING;
4212 
4213   if (!ts->adjoint_max_steps) ts->adjoint_max_steps = ts->total_steps;
4214 
4215   if (ts->steps >= ts->adjoint_max_steps)     ts->reason = TS_CONVERGED_ITS;
4216   while (!ts->reason) {
4217     ierr = TSTrajectoryGet(ts->trajectory,ts,ts->total_steps,&ts->ptime);CHKERRQ(ierr);
4218     ierr = TSAdjointMonitor(ts,ts->total_steps,ts->ptime,ts->vec_sol,ts->numcost,ts->vecs_sensi,ts->vecs_sensip);CHKERRQ(ierr);
4219     ierr = TSAdjointEventHandler(ts);CHKERRQ(ierr);
4220     ierr = TSAdjointStep(ts);CHKERRQ(ierr);
4221     if (ts->vec_costintegral && !ts->costintegralfwd) {
4222       ierr = TSAdjointCostIntegral(ts);CHKERRQ(ierr);
4223     }
4224   }
4225   ierr = TSTrajectoryGet(ts->trajectory,ts,ts->total_steps,&ts->ptime);CHKERRQ(ierr);
4226   ierr = TSAdjointMonitor(ts,ts->total_steps,ts->ptime,ts->vec_sol,ts->numcost,ts->vecs_sensi,ts->vecs_sensip);CHKERRQ(ierr);
4227   ts->solvetime = ts->ptime;
4228   ierr = TSTrajectoryViewFromOptions(ts->trajectory,NULL,"-ts_trajectory_view");CHKERRQ(ierr);
4229   ierr = VecViewFromOptions(ts->vecs_sensi[0],(PetscObject) ts, "-ts_adjoint_view_solution");CHKERRQ(ierr);
4230   PetscFunctionReturn(0);
4231 }
4232 
4233 #undef __FUNCT__
4234 #define __FUNCT__ "TSMonitor"
4235 /*@C
4236    TSMonitor - Runs all user-provided monitor routines set using TSMonitorSet()
4237 
4238    Collective on TS
4239 
4240    Input Parameters:
4241 +  ts - time stepping context obtained from TSCreate()
4242 .  step - step number that has just completed
4243 .  ptime - model time of the state
4244 -  u - state at the current model time
4245 
4246    Notes:
4247    TSMonitor() is typically used automatically within the time stepping implementations.
4248    Users would almost never call this routine directly.
4249 
4250    A step of -1 indicates that the monitor is being called on a solution obtained by interpolating from computed solutions
4251 
4252    Level: developer
4253 
4254 .keywords: TS, timestep
4255 @*/
4256 PetscErrorCode TSMonitor(TS ts,PetscInt step,PetscReal ptime,Vec u)
4257 {
4258   DM             dm;
4259   PetscInt       i,n = ts->numbermonitors;
4260   PetscErrorCode ierr;
4261 
4262   PetscFunctionBegin;
4263   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4264   PetscValidHeaderSpecific(u,VEC_CLASSID,4);
4265 
4266   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
4267   ierr = DMSetOutputSequenceNumber(dm,step,ptime);CHKERRQ(ierr);
4268 
4269   ierr = VecLockPush(u);CHKERRQ(ierr);
4270   for (i=0; i<n; i++) {
4271     ierr = (*ts->monitor[i])(ts,step,ptime,u,ts->monitorcontext[i]);CHKERRQ(ierr);
4272   }
4273   ierr = VecLockPop(u);CHKERRQ(ierr);
4274   PetscFunctionReturn(0);
4275 }
4276 
4277 #undef __FUNCT__
4278 #define __FUNCT__ "TSAdjointMonitor"
4279 /*@C
4280    TSAdjointMonitor - Runs all user-provided adjoint monitor routines set using TSAdjointMonitorSet()
4281 
4282    Collective on TS
4283 
4284    Input Parameters:
4285 +  ts - time stepping context obtained from TSCreate()
4286 .  step - step number that has just completed
4287 .  ptime - model time of the state
4288 .  u - state at the current model time
4289 .  numcost - number of cost functions (dimension of lambda  or mu)
4290 .  lambda - vectors containing the gradients of the cost functions with respect to the ODE/DAE solution variables
4291 -  mu - vectors containing the gradients of the cost functions with respect to the problem parameters
4292 
4293    Notes:
4294    TSAdjointMonitor() is typically used automatically within the time stepping implementations.
4295    Users would almost never call this routine directly.
4296 
4297    Level: developer
4298 
4299 .keywords: TS, timestep
4300 @*/
4301 PetscErrorCode TSAdjointMonitor(TS ts,PetscInt step,PetscReal ptime,Vec u,PetscInt numcost,Vec *lambda, Vec *mu)
4302 {
4303   PetscErrorCode ierr;
4304   PetscInt       i,n = ts->numberadjointmonitors;
4305 
4306   PetscFunctionBegin;
4307   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4308   PetscValidHeaderSpecific(u,VEC_CLASSID,4);
4309   ierr = VecLockPush(u);CHKERRQ(ierr);
4310   for (i=0; i<n; i++) {
4311     ierr = (*ts->adjointmonitor[i])(ts,step,ptime,u,numcost,lambda,mu,ts->adjointmonitorcontext[i]);CHKERRQ(ierr);
4312   }
4313   ierr = VecLockPop(u);CHKERRQ(ierr);
4314   PetscFunctionReturn(0);
4315 }
4316 
4317 /* ------------------------------------------------------------------------*/
4318 #undef __FUNCT__
4319 #define __FUNCT__ "TSMonitorLGCtxCreate"
4320 /*@C
4321    TSMonitorLGCtxCreate - Creates a TSMonitorLGCtx context for use with
4322    TS to monitor the solution process graphically in various ways
4323 
4324    Collective on TS
4325 
4326    Input Parameters:
4327 +  host - the X display to open, or null for the local machine
4328 .  label - the title to put in the title bar
4329 .  x, y - the screen coordinates of the upper left coordinate of the window
4330 .  m, n - the screen width and height in pixels
4331 -  howoften - if positive then determines the frequency of the plotting, if -1 then only at the final time
4332 
4333    Output Parameter:
4334 .  ctx - the context
4335 
4336    Options Database Key:
4337 +  -ts_monitor_lg_timestep - automatically sets line graph monitor
4338 .  -ts_monitor_lg_solution - monitor the solution (or certain values of the solution by calling TSMonitorLGSetDisplayVariables() or TSMonitorLGCtxSetDisplayVariables())
4339 .  -ts_monitor_lg_error -  monitor the error
4340 .  -ts_monitor_lg_ksp_iterations - monitor the number of KSP iterations needed for each timestep
4341 .  -ts_monitor_lg_snes_iterations - monitor the number of SNES iterations needed for each timestep
4342 -  -lg_use_markers <true,false> - mark the data points (at each time step) on the plot; default is true
4343 
4344    Notes:
4345    Use TSMonitorLGCtxDestroy() to destroy.
4346 
4347    One can provide a function that transforms the solution before plotting it with TSMonitorLGCtxSetTransform() or TSMonitorLGSetTransform()
4348 
4349    Many of the functions that control the monitoring have two forms: TSMonitorLGSet/GetXXXX() and TSMonitorLGCtxSet/GetXXXX() the first take a TS object as the
4350    first argument (if that TS object does not have a TSMonitorLGCtx associated with it the function call is ignored) and the second takes a TSMonitorLGCtx object
4351    as the first argument.
4352 
4353    One can control the names displayed for each solution or error variable with TSMonitorLGCtxSetVariableNames() or TSMonitorLGSetVariableNames()
4354 
4355 
4356    Level: intermediate
4357 
4358 .keywords: TS, monitor, line graph, residual
4359 
4360 .seealso: TSMonitorLGTimeStep(), TSMonitorSet(), TSMonitorLGSolution(), TSMonitorLGError(), TSMonitorDefault(), VecView(),
4361            TSMonitorLGCtxCreate(), TSMonitorLGCtxSetVariableNames(), TSMonitorLGCtxGetVariableNames(),
4362            TSMonitorLGSetVariableNames(), TSMonitorLGGetVariableNames(), TSMonitorLGSetDisplayVariables(), TSMonitorLGCtxSetDisplayVariables(),
4363            TSMonitorLGCtxSetTransform(), TSMonitorLGSetTransform(), TSMonitorLGError(), TSMonitorLGSNESIterations(), TSMonitorLGKSPIterations(),
4364            TSMonitorEnvelopeCtxCreate(), TSMonitorEnvelopeGetBounds(), TSMonitorEnvelopeCtxDestroy(), TSMonitorEnvelop()
4365 
4366 @*/
4367 PetscErrorCode  TSMonitorLGCtxCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscInt howoften,TSMonitorLGCtx *ctx)
4368 {
4369   PetscDraw      draw;
4370   PetscErrorCode ierr;
4371 
4372   PetscFunctionBegin;
4373   ierr = PetscNew(ctx);CHKERRQ(ierr);
4374   ierr = PetscDrawCreate(comm,host,label,x,y,m,n,&draw);CHKERRQ(ierr);
4375   ierr = PetscDrawSetFromOptions(draw);CHKERRQ(ierr);
4376   ierr = PetscDrawLGCreate(draw,1,&(*ctx)->lg);CHKERRQ(ierr);
4377   ierr = PetscDrawLGSetFromOptions((*ctx)->lg);CHKERRQ(ierr);
4378   ierr = PetscDrawDestroy(&draw);CHKERRQ(ierr);
4379   (*ctx)->howoften = howoften;
4380   PetscFunctionReturn(0);
4381 }
4382 
4383 #undef __FUNCT__
4384 #define __FUNCT__ "TSMonitorLGTimeStep"
4385 PetscErrorCode TSMonitorLGTimeStep(TS ts,PetscInt step,PetscReal ptime,Vec v,void *monctx)
4386 {
4387   TSMonitorLGCtx ctx = (TSMonitorLGCtx) monctx;
4388   PetscReal      x   = ptime,y;
4389   PetscErrorCode ierr;
4390 
4391   PetscFunctionBegin;
4392   if (step < 0) PetscFunctionReturn(0); /* -1 indicates an interpolated solution */
4393   if (!step) {
4394     PetscDrawAxis axis;
4395     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
4396     ierr = PetscDrawAxisSetLabels(axis,"Timestep as function of time","Time","Time Step");CHKERRQ(ierr);
4397     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
4398   }
4399   ierr = TSGetTimeStep(ts,&y);CHKERRQ(ierr);
4400   ierr = PetscDrawLGAddPoint(ctx->lg,&x,&y);CHKERRQ(ierr);
4401   if (((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason)) {
4402     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
4403     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
4404   }
4405   PetscFunctionReturn(0);
4406 }
4407 
4408 #undef __FUNCT__
4409 #define __FUNCT__ "TSMonitorLGCtxDestroy"
4410 /*@C
4411    TSMonitorLGCtxDestroy - Destroys a line graph context that was created
4412    with TSMonitorLGCtxCreate().
4413 
4414    Collective on TSMonitorLGCtx
4415 
4416    Input Parameter:
4417 .  ctx - the monitor context
4418 
4419    Level: intermediate
4420 
4421 .keywords: TS, monitor, line graph, destroy
4422 
4423 .seealso: TSMonitorLGCtxCreate(),  TSMonitorSet(), TSMonitorLGTimeStep();
4424 @*/
4425 PetscErrorCode  TSMonitorLGCtxDestroy(TSMonitorLGCtx *ctx)
4426 {
4427   PetscErrorCode ierr;
4428 
4429   PetscFunctionBegin;
4430   if ((*ctx)->transformdestroy) {
4431     ierr = ((*ctx)->transformdestroy)((*ctx)->transformctx);CHKERRQ(ierr);
4432   }
4433   ierr = PetscDrawLGDestroy(&(*ctx)->lg);CHKERRQ(ierr);
4434   ierr = PetscStrArrayDestroy(&(*ctx)->names);CHKERRQ(ierr);
4435   ierr = PetscStrArrayDestroy(&(*ctx)->displaynames);CHKERRQ(ierr);
4436   ierr = PetscFree((*ctx)->displayvariables);CHKERRQ(ierr);
4437   ierr = PetscFree((*ctx)->displayvalues);CHKERRQ(ierr);
4438   ierr = PetscFree(*ctx);CHKERRQ(ierr);
4439   PetscFunctionReturn(0);
4440 }
4441 
4442 #undef __FUNCT__
4443 #define __FUNCT__ "TSGetTime"
4444 /*@
4445    TSGetTime - Gets the time of the most recently completed step.
4446 
4447    Not Collective
4448 
4449    Input Parameter:
4450 .  ts - the TS context obtained from TSCreate()
4451 
4452    Output Parameter:
4453 .  t  - the current time. This time may not corresponds to the final time set with TSSetDuration(), use TSGetSolveTime().
4454 
4455    Level: beginner
4456 
4457    Note:
4458    When called during time step evaluation (e.g. during residual evaluation or via hooks set using TSSetPreStep(),
4459    TSSetPreStage(), TSSetPostStage(), or TSSetPostStep()), the time is the time at the start of the step being evaluated.
4460 
4461 .seealso: TSSetInitialTimeStep(), TSGetTimeStep(), TSGetSolveTime()
4462 
4463 .keywords: TS, get, time
4464 @*/
4465 PetscErrorCode  TSGetTime(TS ts,PetscReal *t)
4466 {
4467   PetscFunctionBegin;
4468   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4469   PetscValidRealPointer(t,2);
4470   *t = ts->ptime;
4471   PetscFunctionReturn(0);
4472 }
4473 
4474 #undef __FUNCT__
4475 #define __FUNCT__ "TSGetPrevTime"
4476 /*@
4477    TSGetPrevTime - Gets the starting time of the previously completed step.
4478 
4479    Not Collective
4480 
4481    Input Parameter:
4482 .  ts - the TS context obtained from TSCreate()
4483 
4484    Output Parameter:
4485 .  t  - the previous time
4486 
4487    Level: beginner
4488 
4489 .seealso: TSSetInitialTimeStep(), TSGetTimeStep()
4490 
4491 .keywords: TS, get, time
4492 @*/
4493 PetscErrorCode  TSGetPrevTime(TS ts,PetscReal *t)
4494 {
4495   PetscFunctionBegin;
4496   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4497   PetscValidRealPointer(t,2);
4498   *t = ts->ptime_prev;
4499   PetscFunctionReturn(0);
4500 }
4501 
4502 #undef __FUNCT__
4503 #define __FUNCT__ "TSSetTime"
4504 /*@
4505    TSSetTime - Allows one to reset the time.
4506 
4507    Logically Collective on TS
4508 
4509    Input Parameters:
4510 +  ts - the TS context obtained from TSCreate()
4511 -  time - the time
4512 
4513    Level: intermediate
4514 
4515 .seealso: TSGetTime(), TSSetDuration()
4516 
4517 .keywords: TS, set, time
4518 @*/
4519 PetscErrorCode  TSSetTime(TS ts, PetscReal t)
4520 {
4521   PetscFunctionBegin;
4522   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4523   PetscValidLogicalCollectiveReal(ts,t,2);
4524   ts->ptime = t;
4525   PetscFunctionReturn(0);
4526 }
4527 
4528 #undef __FUNCT__
4529 #define __FUNCT__ "TSSetOptionsPrefix"
4530 /*@C
4531    TSSetOptionsPrefix - Sets the prefix used for searching for all
4532    TS options in the database.
4533 
4534    Logically Collective on TS
4535 
4536    Input Parameter:
4537 +  ts     - The TS context
4538 -  prefix - The prefix to prepend to all option names
4539 
4540    Notes:
4541    A hyphen (-) must NOT be given at the beginning of the prefix name.
4542    The first character of all runtime options is AUTOMATICALLY the
4543    hyphen.
4544 
4545    Level: advanced
4546 
4547 .keywords: TS, set, options, prefix, database
4548 
4549 .seealso: TSSetFromOptions()
4550 
4551 @*/
4552 PetscErrorCode  TSSetOptionsPrefix(TS ts,const char prefix[])
4553 {
4554   PetscErrorCode ierr;
4555   SNES           snes;
4556 
4557   PetscFunctionBegin;
4558   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4559   ierr = PetscObjectSetOptionsPrefix((PetscObject)ts,prefix);CHKERRQ(ierr);
4560   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4561   ierr = SNESSetOptionsPrefix(snes,prefix);CHKERRQ(ierr);
4562   PetscFunctionReturn(0);
4563 }
4564 
4565 
4566 #undef __FUNCT__
4567 #define __FUNCT__ "TSAppendOptionsPrefix"
4568 /*@C
4569    TSAppendOptionsPrefix - Appends to the prefix used for searching for all
4570    TS options in the database.
4571 
4572    Logically Collective on TS
4573 
4574    Input Parameter:
4575 +  ts     - The TS context
4576 -  prefix - The prefix to prepend to all option names
4577 
4578    Notes:
4579    A hyphen (-) must NOT be given at the beginning of the prefix name.
4580    The first character of all runtime options is AUTOMATICALLY the
4581    hyphen.
4582 
4583    Level: advanced
4584 
4585 .keywords: TS, append, options, prefix, database
4586 
4587 .seealso: TSGetOptionsPrefix()
4588 
4589 @*/
4590 PetscErrorCode  TSAppendOptionsPrefix(TS ts,const char prefix[])
4591 {
4592   PetscErrorCode ierr;
4593   SNES           snes;
4594 
4595   PetscFunctionBegin;
4596   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4597   ierr = PetscObjectAppendOptionsPrefix((PetscObject)ts,prefix);CHKERRQ(ierr);
4598   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4599   ierr = SNESAppendOptionsPrefix(snes,prefix);CHKERRQ(ierr);
4600   PetscFunctionReturn(0);
4601 }
4602 
4603 #undef __FUNCT__
4604 #define __FUNCT__ "TSGetOptionsPrefix"
4605 /*@C
4606    TSGetOptionsPrefix - Sets the prefix used for searching for all
4607    TS options in the database.
4608 
4609    Not Collective
4610 
4611    Input Parameter:
4612 .  ts - The TS context
4613 
4614    Output Parameter:
4615 .  prefix - A pointer to the prefix string used
4616 
4617    Notes: On the fortran side, the user should pass in a string 'prifix' of
4618    sufficient length to hold the prefix.
4619 
4620    Level: intermediate
4621 
4622 .keywords: TS, get, options, prefix, database
4623 
4624 .seealso: TSAppendOptionsPrefix()
4625 @*/
4626 PetscErrorCode  TSGetOptionsPrefix(TS ts,const char *prefix[])
4627 {
4628   PetscErrorCode ierr;
4629 
4630   PetscFunctionBegin;
4631   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4632   PetscValidPointer(prefix,2);
4633   ierr = PetscObjectGetOptionsPrefix((PetscObject)ts,prefix);CHKERRQ(ierr);
4634   PetscFunctionReturn(0);
4635 }
4636 
4637 #undef __FUNCT__
4638 #define __FUNCT__ "TSGetRHSJacobian"
4639 /*@C
4640    TSGetRHSJacobian - Returns the Jacobian J at the present timestep.
4641 
4642    Not Collective, but parallel objects are returned if TS is parallel
4643 
4644    Input Parameter:
4645 .  ts  - The TS context obtained from TSCreate()
4646 
4647    Output Parameters:
4648 +  Amat - The (approximate) Jacobian J of G, where U_t = G(U,t)  (or NULL)
4649 .  Pmat - The matrix from which the preconditioner is constructed, usually the same as Amat  (or NULL)
4650 .  func - Function to compute the Jacobian of the RHS  (or NULL)
4651 -  ctx - User-defined context for Jacobian evaluation routine  (or NULL)
4652 
4653    Notes: You can pass in NULL for any return argument you do not need.
4654 
4655    Level: intermediate
4656 
4657 .seealso: TSGetTimeStep(), TSGetMatrices(), TSGetTime(), TSGetTimeStepNumber()
4658 
4659 .keywords: TS, timestep, get, matrix, Jacobian
4660 @*/
4661 PetscErrorCode  TSGetRHSJacobian(TS ts,Mat *Amat,Mat *Pmat,TSRHSJacobian *func,void **ctx)
4662 {
4663   PetscErrorCode ierr;
4664   SNES           snes;
4665   DM             dm;
4666 
4667   PetscFunctionBegin;
4668   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4669   ierr = SNESGetJacobian(snes,Amat,Pmat,NULL,NULL);CHKERRQ(ierr);
4670   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
4671   ierr = DMTSGetRHSJacobian(dm,func,ctx);CHKERRQ(ierr);
4672   PetscFunctionReturn(0);
4673 }
4674 
4675 #undef __FUNCT__
4676 #define __FUNCT__ "TSGetIJacobian"
4677 /*@C
4678    TSGetIJacobian - Returns the implicit Jacobian at the present timestep.
4679 
4680    Not Collective, but parallel objects are returned if TS is parallel
4681 
4682    Input Parameter:
4683 .  ts  - The TS context obtained from TSCreate()
4684 
4685    Output Parameters:
4686 +  Amat  - The (approximate) Jacobian of F(t,U,U_t)
4687 .  Pmat - The matrix from which the preconditioner is constructed, often the same as Amat
4688 .  f   - The function to compute the matrices
4689 - ctx - User-defined context for Jacobian evaluation routine
4690 
4691    Notes: You can pass in NULL for any return argument you do not need.
4692 
4693    Level: advanced
4694 
4695 .seealso: TSGetTimeStep(), TSGetRHSJacobian(), TSGetMatrices(), TSGetTime(), TSGetTimeStepNumber()
4696 
4697 .keywords: TS, timestep, get, matrix, Jacobian
4698 @*/
4699 PetscErrorCode  TSGetIJacobian(TS ts,Mat *Amat,Mat *Pmat,TSIJacobian *f,void **ctx)
4700 {
4701   PetscErrorCode ierr;
4702   SNES           snes;
4703   DM             dm;
4704 
4705   PetscFunctionBegin;
4706   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4707   ierr = SNESSetUpMatrices(snes);CHKERRQ(ierr);
4708   ierr = SNESGetJacobian(snes,Amat,Pmat,NULL,NULL);CHKERRQ(ierr);
4709   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
4710   ierr = DMTSGetIJacobian(dm,f,ctx);CHKERRQ(ierr);
4711   PetscFunctionReturn(0);
4712 }
4713 
4714 
4715 #undef __FUNCT__
4716 #define __FUNCT__ "TSMonitorDrawSolution"
4717 /*@C
4718    TSMonitorDrawSolution - Monitors progress of the TS solvers by calling
4719    VecView() for the solution at each timestep
4720 
4721    Collective on TS
4722 
4723    Input Parameters:
4724 +  ts - the TS context
4725 .  step - current time-step
4726 .  ptime - current time
4727 -  dummy - either a viewer or NULL
4728 
4729    Options Database:
4730 .   -ts_monitor_draw_solution_initial - show initial solution as well as current solution
4731 
4732    Notes: the initial solution and current solution are not display with a common axis scaling so generally the option -ts_monitor_draw_solution_initial
4733        will look bad
4734 
4735    Level: intermediate
4736 
4737 .keywords: TS,  vector, monitor, view
4738 
4739 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
4740 @*/
4741 PetscErrorCode  TSMonitorDrawSolution(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
4742 {
4743   PetscErrorCode   ierr;
4744   TSMonitorDrawCtx ictx = (TSMonitorDrawCtx)dummy;
4745   PetscDraw        draw;
4746 
4747   PetscFunctionBegin;
4748   if (!step && ictx->showinitial) {
4749     if (!ictx->initialsolution) {
4750       ierr = VecDuplicate(u,&ictx->initialsolution);CHKERRQ(ierr);
4751     }
4752     ierr = VecCopy(u,ictx->initialsolution);CHKERRQ(ierr);
4753   }
4754   if (!(((ictx->howoften > 0) && (!(step % ictx->howoften))) || ((ictx->howoften == -1) && ts->reason))) PetscFunctionReturn(0);
4755 
4756   if (ictx->showinitial) {
4757     PetscReal pause;
4758     ierr = PetscViewerDrawGetPause(ictx->viewer,&pause);CHKERRQ(ierr);
4759     ierr = PetscViewerDrawSetPause(ictx->viewer,0.0);CHKERRQ(ierr);
4760     ierr = VecView(ictx->initialsolution,ictx->viewer);CHKERRQ(ierr);
4761     ierr = PetscViewerDrawSetPause(ictx->viewer,pause);CHKERRQ(ierr);
4762     ierr = PetscViewerDrawSetHold(ictx->viewer,PETSC_TRUE);CHKERRQ(ierr);
4763   }
4764   ierr = VecView(u,ictx->viewer);CHKERRQ(ierr);
4765   if (ictx->showtimestepandtime) {
4766     PetscReal xl,yl,xr,yr,h;
4767     char      time[32];
4768 
4769     ierr = PetscViewerDrawGetDraw(ictx->viewer,0,&draw);CHKERRQ(ierr);
4770     ierr = PetscSNPrintf(time,32,"Timestep %d Time %g",(int)step,(double)ptime);CHKERRQ(ierr);
4771     ierr = PetscDrawGetCoordinates(draw,&xl,&yl,&xr,&yr);CHKERRQ(ierr);
4772     h    = yl + .95*(yr - yl);
4773     ierr = PetscDrawStringCentered(draw,.5*(xl+xr),h,PETSC_DRAW_BLACK,time);CHKERRQ(ierr);
4774     ierr = PetscDrawFlush(draw);CHKERRQ(ierr);
4775   }
4776 
4777   if (ictx->showinitial) {
4778     ierr = PetscViewerDrawSetHold(ictx->viewer,PETSC_FALSE);CHKERRQ(ierr);
4779   }
4780   PetscFunctionReturn(0);
4781 }
4782 
4783 #undef __FUNCT__
4784 #define __FUNCT__ "TSAdjointMonitorDrawSensi"
4785 /*@C
4786    TSAdjointMonitorDrawSensi - Monitors progress of the adjoint TS solvers by calling
4787    VecView() for the sensitivities to initial states at each timestep
4788 
4789    Collective on TS
4790 
4791    Input Parameters:
4792 +  ts - the TS context
4793 .  step - current time-step
4794 .  ptime - current time
4795 .  u - current state
4796 .  numcost - number of cost functions
4797 .  lambda - sensitivities to initial conditions
4798 .  mu - sensitivities to parameters
4799 -  dummy - either a viewer or NULL
4800 
4801    Level: intermediate
4802 
4803 .keywords: TS,  vector, adjoint, monitor, view
4804 
4805 .seealso: TSAdjointMonitorSet(), TSAdjointMonitorDefault(), VecView()
4806 @*/
4807 PetscErrorCode  TSAdjointMonitorDrawSensi(TS ts,PetscInt step,PetscReal ptime,Vec u,PetscInt numcost,Vec *lambda,Vec *mu,void *dummy)
4808 {
4809   PetscErrorCode   ierr;
4810   TSMonitorDrawCtx ictx = (TSMonitorDrawCtx)dummy;
4811   PetscDraw        draw;
4812   PetscReal        xl,yl,xr,yr,h;
4813   char             time[32];
4814 
4815   PetscFunctionBegin;
4816   if (!(((ictx->howoften > 0) && (!(step % ictx->howoften))) || ((ictx->howoften == -1) && ts->reason))) PetscFunctionReturn(0);
4817 
4818   ierr = VecView(lambda[0],ictx->viewer);CHKERRQ(ierr);
4819   ierr = PetscViewerDrawGetDraw(ictx->viewer,0,&draw);CHKERRQ(ierr);
4820   ierr = PetscSNPrintf(time,32,"Timestep %d Time %g",(int)step,(double)ptime);CHKERRQ(ierr);
4821   ierr = PetscDrawGetCoordinates(draw,&xl,&yl,&xr,&yr);CHKERRQ(ierr);
4822   h    = yl + .95*(yr - yl);
4823   ierr = PetscDrawStringCentered(draw,.5*(xl+xr),h,PETSC_DRAW_BLACK,time);CHKERRQ(ierr);
4824   ierr = PetscDrawFlush(draw);CHKERRQ(ierr);
4825   PetscFunctionReturn(0);
4826 }
4827 
4828 #undef __FUNCT__
4829 #define __FUNCT__ "TSMonitorDrawSolutionPhase"
4830 /*@C
4831    TSMonitorDrawSolutionPhase - Monitors progress of the TS solvers by plotting the solution as a phase diagram
4832 
4833    Collective on TS
4834 
4835    Input Parameters:
4836 +  ts - the TS context
4837 .  step - current time-step
4838 .  ptime - current time
4839 -  dummy - either a viewer or NULL
4840 
4841    Level: intermediate
4842 
4843 .keywords: TS,  vector, monitor, view
4844 
4845 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
4846 @*/
4847 PetscErrorCode  TSMonitorDrawSolutionPhase(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
4848 {
4849   PetscErrorCode    ierr;
4850   TSMonitorDrawCtx  ictx = (TSMonitorDrawCtx)dummy;
4851   PetscDraw         draw;
4852   PetscDrawAxis     axis;
4853   PetscInt          n;
4854   PetscMPIInt       size;
4855   PetscReal         U0,U1,xl,yl,xr,yr,h;
4856   char              time[32];
4857   const PetscScalar *U;
4858 
4859   PetscFunctionBegin;
4860   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)ts),&size);CHKERRQ(ierr);
4861   if (size != 1) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Only allowed for sequential runs");
4862   ierr = VecGetSize(u,&n);CHKERRQ(ierr);
4863   if (n != 2) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Only for ODEs with two unknowns");
4864 
4865   ierr = PetscViewerDrawGetDraw(ictx->viewer,0,&draw);CHKERRQ(ierr);
4866   ierr = PetscViewerDrawGetDrawAxis(ictx->viewer,0,&axis);CHKERRQ(ierr);
4867   ierr = PetscDrawAxisGetLimits(axis,&xl,&xr,&yl,&yr);CHKERRQ(ierr);
4868   if (!step) {
4869     ierr = PetscDrawClear(draw);CHKERRQ(ierr);
4870     ierr = PetscDrawAxisDraw(axis);CHKERRQ(ierr);
4871   }
4872 
4873   ierr = VecGetArrayRead(u,&U);CHKERRQ(ierr);
4874   U0 = PetscRealPart(U[0]);
4875   U1 = PetscRealPart(U[1]);
4876   ierr = VecRestoreArrayRead(u,&U);CHKERRQ(ierr);
4877   if ((U0 < xl) || (U1 < yl) || (U0 > xr) || (U1 > yr)) PetscFunctionReturn(0);
4878 
4879   ierr = PetscDrawCollectiveBegin(draw);CHKERRQ(ierr);
4880   ierr = PetscDrawPoint(draw,U0,U1,PETSC_DRAW_BLACK);CHKERRQ(ierr);
4881   if (ictx->showtimestepandtime) {
4882     ierr = PetscDrawGetCoordinates(draw,&xl,&yl,&xr,&yr);CHKERRQ(ierr);
4883     ierr = PetscSNPrintf(time,32,"Timestep %d Time %g",(int)step,(double)ptime);CHKERRQ(ierr);
4884     h    = yl + .95*(yr - yl);
4885     ierr = PetscDrawStringCentered(draw,.5*(xl+xr),h,PETSC_DRAW_BLACK,time);CHKERRQ(ierr);
4886   }
4887   ierr = PetscDrawCollectiveEnd(draw);CHKERRQ(ierr);
4888   ierr = PetscDrawFlush(draw);CHKERRQ(ierr);
4889   ierr = PetscDrawSave(draw);CHKERRQ(ierr);
4890   PetscFunctionReturn(0);
4891 }
4892 
4893 
4894 #undef __FUNCT__
4895 #define __FUNCT__ "TSMonitorDrawCtxDestroy"
4896 /*@C
4897    TSMonitorDrawCtxDestroy - Destroys the monitor context for TSMonitorDrawSolution()
4898 
4899    Collective on TS
4900 
4901    Input Parameters:
4902 .    ctx - the monitor context
4903 
4904    Level: intermediate
4905 
4906 .keywords: TS,  vector, monitor, view
4907 
4908 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorDrawSolution(), TSMonitorDrawError()
4909 @*/
4910 PetscErrorCode  TSMonitorDrawCtxDestroy(TSMonitorDrawCtx *ictx)
4911 {
4912   PetscErrorCode ierr;
4913 
4914   PetscFunctionBegin;
4915   ierr = PetscViewerDestroy(&(*ictx)->viewer);CHKERRQ(ierr);
4916   ierr = VecDestroy(&(*ictx)->initialsolution);CHKERRQ(ierr);
4917   ierr = PetscFree(*ictx);CHKERRQ(ierr);
4918   PetscFunctionReturn(0);
4919 }
4920 
4921 #undef __FUNCT__
4922 #define __FUNCT__ "TSMonitorDrawCtxCreate"
4923 /*@C
4924    TSMonitorDrawCtxCreate - Creates the monitor context for TSMonitorDrawCtx
4925 
4926    Collective on TS
4927 
4928    Input Parameter:
4929 .    ts - time-step context
4930 
4931    Output Patameter:
4932 .    ctx - the monitor context
4933 
4934    Options Database:
4935 .   -ts_monitor_draw_solution_initial - show initial solution as well as current solution
4936 
4937    Level: intermediate
4938 
4939 .keywords: TS,  vector, monitor, view
4940 
4941 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorDrawCtx()
4942 @*/
4943 PetscErrorCode  TSMonitorDrawCtxCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscInt howoften,TSMonitorDrawCtx *ctx)
4944 {
4945   PetscErrorCode   ierr;
4946 
4947   PetscFunctionBegin;
4948   ierr = PetscNew(ctx);CHKERRQ(ierr);
4949   ierr = PetscViewerDrawOpen(comm,host,label,x,y,m,n,&(*ctx)->viewer);CHKERRQ(ierr);
4950   ierr = PetscViewerSetFromOptions((*ctx)->viewer);CHKERRQ(ierr);
4951 
4952   (*ctx)->howoften    = howoften;
4953   (*ctx)->showinitial = PETSC_FALSE;
4954   ierr = PetscOptionsGetBool(NULL,NULL,"-ts_monitor_draw_solution_initial",&(*ctx)->showinitial,NULL);CHKERRQ(ierr);
4955 
4956   (*ctx)->showtimestepandtime = PETSC_FALSE;
4957   ierr = PetscOptionsGetBool(NULL,NULL,"-ts_monitor_draw_solution_show_time",&(*ctx)->showtimestepandtime,NULL);CHKERRQ(ierr);
4958   PetscFunctionReturn(0);
4959 }
4960 
4961 #undef __FUNCT__
4962 #define __FUNCT__ "TSMonitorDrawError"
4963 /*@C
4964    TSMonitorDrawError - Monitors progress of the TS solvers by calling
4965    VecView() for the error at each timestep
4966 
4967    Collective on TS
4968 
4969    Input Parameters:
4970 +  ts - the TS context
4971 .  step - current time-step
4972 .  ptime - current time
4973 -  dummy - either a viewer or NULL
4974 
4975    Level: intermediate
4976 
4977 .keywords: TS,  vector, monitor, view
4978 
4979 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
4980 @*/
4981 PetscErrorCode  TSMonitorDrawError(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
4982 {
4983   PetscErrorCode   ierr;
4984   TSMonitorDrawCtx ctx    = (TSMonitorDrawCtx)dummy;
4985   PetscViewer      viewer = ctx->viewer;
4986   Vec              work;
4987 
4988   PetscFunctionBegin;
4989   if (!(((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason))) PetscFunctionReturn(0);
4990   ierr = VecDuplicate(u,&work);CHKERRQ(ierr);
4991   ierr = TSComputeSolutionFunction(ts,ptime,work);CHKERRQ(ierr);
4992   ierr = VecAXPY(work,-1.0,u);CHKERRQ(ierr);
4993   ierr = VecView(work,viewer);CHKERRQ(ierr);
4994   ierr = VecDestroy(&work);CHKERRQ(ierr);
4995   PetscFunctionReturn(0);
4996 }
4997 
4998 #include <petsc/private/dmimpl.h>
4999 #undef __FUNCT__
5000 #define __FUNCT__ "TSSetDM"
5001 /*@
5002    TSSetDM - Sets the DM that may be used by some nonlinear solvers or preconditioners under the TS
5003 
5004    Logically Collective on TS and DM
5005 
5006    Input Parameters:
5007 +  ts - the ODE integrator object
5008 -  dm - the dm, cannot be NULL
5009 
5010    Level: intermediate
5011 
5012 
5013 .seealso: TSGetDM(), SNESSetDM(), SNESGetDM()
5014 @*/
5015 PetscErrorCode  TSSetDM(TS ts,DM dm)
5016 {
5017   PetscErrorCode ierr;
5018   SNES           snes;
5019   DMTS           tsdm;
5020 
5021   PetscFunctionBegin;
5022   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5023   PetscValidHeaderSpecific(dm,DM_CLASSID,2);
5024   ierr = PetscObjectReference((PetscObject)dm);CHKERRQ(ierr);
5025   if (ts->dm) {               /* Move the DMTS context over to the new DM unless the new DM already has one */
5026     if (ts->dm->dmts && !dm->dmts) {
5027       ierr = DMCopyDMTS(ts->dm,dm);CHKERRQ(ierr);
5028       ierr = DMGetDMTS(ts->dm,&tsdm);CHKERRQ(ierr);
5029       if (tsdm->originaldm == ts->dm) { /* Grant write privileges to the replacement DM */
5030         tsdm->originaldm = dm;
5031       }
5032     }
5033     ierr = DMDestroy(&ts->dm);CHKERRQ(ierr);
5034   }
5035   ts->dm = dm;
5036 
5037   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
5038   ierr = SNESSetDM(snes,dm);CHKERRQ(ierr);
5039   PetscFunctionReturn(0);
5040 }
5041 
5042 #undef __FUNCT__
5043 #define __FUNCT__ "TSGetDM"
5044 /*@
5045    TSGetDM - Gets the DM that may be used by some preconditioners
5046 
5047    Not Collective
5048 
5049    Input Parameter:
5050 . ts - the preconditioner context
5051 
5052    Output Parameter:
5053 .  dm - the dm
5054 
5055    Level: intermediate
5056 
5057 
5058 .seealso: TSSetDM(), SNESSetDM(), SNESGetDM()
5059 @*/
5060 PetscErrorCode  TSGetDM(TS ts,DM *dm)
5061 {
5062   PetscErrorCode ierr;
5063 
5064   PetscFunctionBegin;
5065   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5066   if (!ts->dm) {
5067     ierr = DMShellCreate(PetscObjectComm((PetscObject)ts),&ts->dm);CHKERRQ(ierr);
5068     if (ts->snes) {ierr = SNESSetDM(ts->snes,ts->dm);CHKERRQ(ierr);}
5069   }
5070   *dm = ts->dm;
5071   PetscFunctionReturn(0);
5072 }
5073 
5074 #undef __FUNCT__
5075 #define __FUNCT__ "SNESTSFormFunction"
5076 /*@
5077    SNESTSFormFunction - Function to evaluate nonlinear residual
5078 
5079    Logically Collective on SNES
5080 
5081    Input Parameter:
5082 + snes - nonlinear solver
5083 . U - the current state at which to evaluate the residual
5084 - ctx - user context, must be a TS
5085 
5086    Output Parameter:
5087 . F - the nonlinear residual
5088 
5089    Notes:
5090    This function is not normally called by users and is automatically registered with the SNES used by TS.
5091    It is most frequently passed to MatFDColoringSetFunction().
5092 
5093    Level: advanced
5094 
5095 .seealso: SNESSetFunction(), MatFDColoringSetFunction()
5096 @*/
5097 PetscErrorCode  SNESTSFormFunction(SNES snes,Vec U,Vec F,void *ctx)
5098 {
5099   TS             ts = (TS)ctx;
5100   PetscErrorCode ierr;
5101 
5102   PetscFunctionBegin;
5103   PetscValidHeaderSpecific(snes,SNES_CLASSID,1);
5104   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
5105   PetscValidHeaderSpecific(F,VEC_CLASSID,3);
5106   PetscValidHeaderSpecific(ts,TS_CLASSID,4);
5107   ierr = (ts->ops->snesfunction)(snes,U,F,ts);CHKERRQ(ierr);
5108   PetscFunctionReturn(0);
5109 }
5110 
5111 #undef __FUNCT__
5112 #define __FUNCT__ "SNESTSFormJacobian"
5113 /*@
5114    SNESTSFormJacobian - Function to evaluate the Jacobian
5115 
5116    Collective on SNES
5117 
5118    Input Parameter:
5119 + snes - nonlinear solver
5120 . U - the current state at which to evaluate the residual
5121 - ctx - user context, must be a TS
5122 
5123    Output Parameter:
5124 + A - the Jacobian
5125 . B - the preconditioning matrix (may be the same as A)
5126 - flag - indicates any structure change in the matrix
5127 
5128    Notes:
5129    This function is not normally called by users and is automatically registered with the SNES used by TS.
5130 
5131    Level: developer
5132 
5133 .seealso: SNESSetJacobian()
5134 @*/
5135 PetscErrorCode  SNESTSFormJacobian(SNES snes,Vec U,Mat A,Mat B,void *ctx)
5136 {
5137   TS             ts = (TS)ctx;
5138   PetscErrorCode ierr;
5139 
5140   PetscFunctionBegin;
5141   PetscValidHeaderSpecific(snes,SNES_CLASSID,1);
5142   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
5143   PetscValidPointer(A,3);
5144   PetscValidHeaderSpecific(A,MAT_CLASSID,3);
5145   PetscValidPointer(B,4);
5146   PetscValidHeaderSpecific(B,MAT_CLASSID,4);
5147   PetscValidHeaderSpecific(ts,TS_CLASSID,6);
5148   ierr = (ts->ops->snesjacobian)(snes,U,A,B,ts);CHKERRQ(ierr);
5149   PetscFunctionReturn(0);
5150 }
5151 
5152 #undef __FUNCT__
5153 #define __FUNCT__ "TSComputeRHSFunctionLinear"
5154 /*@C
5155    TSComputeRHSFunctionLinear - Evaluate the right hand side via the user-provided Jacobian, for linear problems Udot = A U only
5156 
5157    Collective on TS
5158 
5159    Input Arguments:
5160 +  ts - time stepping context
5161 .  t - time at which to evaluate
5162 .  U - state at which to evaluate
5163 -  ctx - context
5164 
5165    Output Arguments:
5166 .  F - right hand side
5167 
5168    Level: intermediate
5169 
5170    Notes:
5171    This function is intended to be passed to TSSetRHSFunction() to evaluate the right hand side for linear problems.
5172    The matrix (and optionally the evaluation context) should be passed to TSSetRHSJacobian().
5173 
5174 .seealso: TSSetRHSFunction(), TSSetRHSJacobian(), TSComputeRHSJacobianConstant()
5175 @*/
5176 PetscErrorCode TSComputeRHSFunctionLinear(TS ts,PetscReal t,Vec U,Vec F,void *ctx)
5177 {
5178   PetscErrorCode ierr;
5179   Mat            Arhs,Brhs;
5180 
5181   PetscFunctionBegin;
5182   ierr = TSGetRHSMats_Private(ts,&Arhs,&Brhs);CHKERRQ(ierr);
5183   ierr = TSComputeRHSJacobian(ts,t,U,Arhs,Brhs);CHKERRQ(ierr);
5184   ierr = MatMult(Arhs,U,F);CHKERRQ(ierr);
5185   PetscFunctionReturn(0);
5186 }
5187 
5188 #undef __FUNCT__
5189 #define __FUNCT__ "TSComputeRHSJacobianConstant"
5190 /*@C
5191    TSComputeRHSJacobianConstant - Reuses a Jacobian that is time-independent.
5192 
5193    Collective on TS
5194 
5195    Input Arguments:
5196 +  ts - time stepping context
5197 .  t - time at which to evaluate
5198 .  U - state at which to evaluate
5199 -  ctx - context
5200 
5201    Output Arguments:
5202 +  A - pointer to operator
5203 .  B - pointer to preconditioning matrix
5204 -  flg - matrix structure flag
5205 
5206    Level: intermediate
5207 
5208    Notes:
5209    This function is intended to be passed to TSSetRHSJacobian() to evaluate the Jacobian for linear time-independent problems.
5210 
5211 .seealso: TSSetRHSFunction(), TSSetRHSJacobian(), TSComputeRHSFunctionLinear()
5212 @*/
5213 PetscErrorCode TSComputeRHSJacobianConstant(TS ts,PetscReal t,Vec U,Mat A,Mat B,void *ctx)
5214 {
5215   PetscFunctionBegin;
5216   PetscFunctionReturn(0);
5217 }
5218 
5219 #undef __FUNCT__
5220 #define __FUNCT__ "TSComputeIFunctionLinear"
5221 /*@C
5222    TSComputeIFunctionLinear - Evaluate the left hand side via the user-provided Jacobian, for linear problems only
5223 
5224    Collective on TS
5225 
5226    Input Arguments:
5227 +  ts - time stepping context
5228 .  t - time at which to evaluate
5229 .  U - state at which to evaluate
5230 .  Udot - time derivative of state vector
5231 -  ctx - context
5232 
5233    Output Arguments:
5234 .  F - left hand side
5235 
5236    Level: intermediate
5237 
5238    Notes:
5239    The assumption here is that the left hand side is of the form A*Udot (and not A*Udot + B*U). For other cases, the
5240    user is required to write their own TSComputeIFunction.
5241    This function is intended to be passed to TSSetIFunction() to evaluate the left hand side for linear problems.
5242    The matrix (and optionally the evaluation context) should be passed to TSSetIJacobian().
5243 
5244    Note that using this function is NOT equivalent to using TSComputeRHSFunctionLinear() since that solves Udot = A U
5245 
5246 .seealso: TSSetIFunction(), TSSetIJacobian(), TSComputeIJacobianConstant(), TSComputeRHSFunctionLinear()
5247 @*/
5248 PetscErrorCode TSComputeIFunctionLinear(TS ts,PetscReal t,Vec U,Vec Udot,Vec F,void *ctx)
5249 {
5250   PetscErrorCode ierr;
5251   Mat            A,B;
5252 
5253   PetscFunctionBegin;
5254   ierr = TSGetIJacobian(ts,&A,&B,NULL,NULL);CHKERRQ(ierr);
5255   ierr = TSComputeIJacobian(ts,t,U,Udot,1.0,A,B,PETSC_TRUE);CHKERRQ(ierr);
5256   ierr = MatMult(A,Udot,F);CHKERRQ(ierr);
5257   PetscFunctionReturn(0);
5258 }
5259 
5260 #undef __FUNCT__
5261 #define __FUNCT__ "TSComputeIJacobianConstant"
5262 /*@C
5263    TSComputeIJacobianConstant - Reuses a time-independent for a semi-implicit DAE or ODE
5264 
5265    Collective on TS
5266 
5267    Input Arguments:
5268 +  ts - time stepping context
5269 .  t - time at which to evaluate
5270 .  U - state at which to evaluate
5271 .  Udot - time derivative of state vector
5272 .  shift - shift to apply
5273 -  ctx - context
5274 
5275    Output Arguments:
5276 +  A - pointer to operator
5277 .  B - pointer to preconditioning matrix
5278 -  flg - matrix structure flag
5279 
5280    Level: advanced
5281 
5282    Notes:
5283    This function is intended to be passed to TSSetIJacobian() to evaluate the Jacobian for linear time-independent problems.
5284 
5285    It is only appropriate for problems of the form
5286 
5287 $     M Udot = F(U,t)
5288 
5289   where M is constant and F is non-stiff.  The user must pass M to TSSetIJacobian().  The current implementation only
5290   works with IMEX time integration methods such as TSROSW and TSARKIMEX, since there is no support for de-constructing
5291   an implicit operator of the form
5292 
5293 $    shift*M + J
5294 
5295   where J is the Jacobian of -F(U).  Support may be added in a future version of PETSc, but for now, the user must store
5296   a copy of M or reassemble it when requested.
5297 
5298 .seealso: TSSetIFunction(), TSSetIJacobian(), TSComputeIFunctionLinear()
5299 @*/
5300 PetscErrorCode TSComputeIJacobianConstant(TS ts,PetscReal t,Vec U,Vec Udot,PetscReal shift,Mat A,Mat B,void *ctx)
5301 {
5302   PetscErrorCode ierr;
5303 
5304   PetscFunctionBegin;
5305   ierr = MatScale(A, shift / ts->ijacobian.shift);CHKERRQ(ierr);
5306   ts->ijacobian.shift = shift;
5307   PetscFunctionReturn(0);
5308 }
5309 
5310 #undef __FUNCT__
5311 #define __FUNCT__ "TSGetEquationType"
5312 /*@
5313    TSGetEquationType - Gets the type of the equation that TS is solving.
5314 
5315    Not Collective
5316 
5317    Input Parameter:
5318 .  ts - the TS context
5319 
5320    Output Parameter:
5321 .  equation_type - see TSEquationType
5322 
5323    Level: beginner
5324 
5325 .keywords: TS, equation type
5326 
5327 .seealso: TSSetEquationType(), TSEquationType
5328 @*/
5329 PetscErrorCode  TSGetEquationType(TS ts,TSEquationType *equation_type)
5330 {
5331   PetscFunctionBegin;
5332   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5333   PetscValidPointer(equation_type,2);
5334   *equation_type = ts->equation_type;
5335   PetscFunctionReturn(0);
5336 }
5337 
5338 #undef __FUNCT__
5339 #define __FUNCT__ "TSSetEquationType"
5340 /*@
5341    TSSetEquationType - Sets the type of the equation that TS is solving.
5342 
5343    Not Collective
5344 
5345    Input Parameter:
5346 +  ts - the TS context
5347 -  equation_type - see TSEquationType
5348 
5349    Level: advanced
5350 
5351 .keywords: TS, equation type
5352 
5353 .seealso: TSGetEquationType(), TSEquationType
5354 @*/
5355 PetscErrorCode  TSSetEquationType(TS ts,TSEquationType equation_type)
5356 {
5357   PetscFunctionBegin;
5358   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5359   ts->equation_type = equation_type;
5360   PetscFunctionReturn(0);
5361 }
5362 
5363 #undef __FUNCT__
5364 #define __FUNCT__ "TSGetConvergedReason"
5365 /*@
5366    TSGetConvergedReason - Gets the reason the TS iteration was stopped.
5367 
5368    Not Collective
5369 
5370    Input Parameter:
5371 .  ts - the TS context
5372 
5373    Output Parameter:
5374 .  reason - negative value indicates diverged, positive value converged, see TSConvergedReason or the
5375             manual pages for the individual convergence tests for complete lists
5376 
5377    Level: beginner
5378 
5379    Notes:
5380    Can only be called after the call to TSSolve() is complete.
5381 
5382 .keywords: TS, nonlinear, set, convergence, test
5383 
5384 .seealso: TSSetConvergenceTest(), TSConvergedReason
5385 @*/
5386 PetscErrorCode  TSGetConvergedReason(TS ts,TSConvergedReason *reason)
5387 {
5388   PetscFunctionBegin;
5389   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5390   PetscValidPointer(reason,2);
5391   *reason = ts->reason;
5392   PetscFunctionReturn(0);
5393 }
5394 
5395 #undef __FUNCT__
5396 #define __FUNCT__ "TSSetConvergedReason"
5397 /*@
5398    TSSetConvergedReason - Sets the reason for handling the convergence of TSSolve.
5399 
5400    Not Collective
5401 
5402    Input Parameter:
5403 +  ts - the TS context
5404 .  reason - negative value indicates diverged, positive value converged, see TSConvergedReason or the
5405             manual pages for the individual convergence tests for complete lists
5406 
5407    Level: advanced
5408 
5409    Notes:
5410    Can only be called during TSSolve() is active.
5411 
5412 .keywords: TS, nonlinear, set, convergence, test
5413 
5414 .seealso: TSConvergedReason
5415 @*/
5416 PetscErrorCode  TSSetConvergedReason(TS ts,TSConvergedReason reason)
5417 {
5418   PetscFunctionBegin;
5419   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5420   ts->reason = reason;
5421   PetscFunctionReturn(0);
5422 }
5423 
5424 #undef __FUNCT__
5425 #define __FUNCT__ "TSGetSolveTime"
5426 /*@
5427    TSGetSolveTime - Gets the time after a call to TSSolve()
5428 
5429    Not Collective
5430 
5431    Input Parameter:
5432 .  ts - the TS context
5433 
5434    Output Parameter:
5435 .  ftime - the final time. This time corresponds to the final time set with TSSetDuration()
5436 
5437    Level: beginner
5438 
5439    Notes:
5440    Can only be called after the call to TSSolve() is complete.
5441 
5442 .keywords: TS, nonlinear, set, convergence, test
5443 
5444 .seealso: TSSetConvergenceTest(), TSConvergedReason
5445 @*/
5446 PetscErrorCode  TSGetSolveTime(TS ts,PetscReal *ftime)
5447 {
5448   PetscFunctionBegin;
5449   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5450   PetscValidPointer(ftime,2);
5451   *ftime = ts->solvetime;
5452   PetscFunctionReturn(0);
5453 }
5454 
5455 #undef __FUNCT__
5456 #define __FUNCT__ "TSGetTotalSteps"
5457 /*@
5458    TSGetTotalSteps - Gets the total number of steps done since the last call to TSSetUp() or TSCreate()
5459 
5460    Not Collective
5461 
5462    Input Parameter:
5463 .  ts - the TS context
5464 
5465    Output Parameter:
5466 .  steps - the number of steps
5467 
5468    Level: beginner
5469 
5470    Notes:
5471    Includes the number of steps for all calls to TSSolve() since TSSetUp() was called
5472 
5473 .keywords: TS, nonlinear, set, convergence, test
5474 
5475 .seealso: TSSetConvergenceTest(), TSConvergedReason
5476 @*/
5477 PetscErrorCode  TSGetTotalSteps(TS ts,PetscInt *steps)
5478 {
5479   PetscFunctionBegin;
5480   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5481   PetscValidPointer(steps,2);
5482   *steps = ts->total_steps;
5483   PetscFunctionReturn(0);
5484 }
5485 
5486 #undef __FUNCT__
5487 #define __FUNCT__ "TSGetSNESIterations"
5488 /*@
5489    TSGetSNESIterations - Gets the total number of nonlinear iterations
5490    used by the time integrator.
5491 
5492    Not Collective
5493 
5494    Input Parameter:
5495 .  ts - TS context
5496 
5497    Output Parameter:
5498 .  nits - number of nonlinear iterations
5499 
5500    Notes:
5501    This counter is reset to zero for each successive call to TSSolve().
5502 
5503    Level: intermediate
5504 
5505 .keywords: TS, get, number, nonlinear, iterations
5506 
5507 .seealso:  TSGetKSPIterations()
5508 @*/
5509 PetscErrorCode TSGetSNESIterations(TS ts,PetscInt *nits)
5510 {
5511   PetscFunctionBegin;
5512   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5513   PetscValidIntPointer(nits,2);
5514   *nits = ts->snes_its;
5515   PetscFunctionReturn(0);
5516 }
5517 
5518 #undef __FUNCT__
5519 #define __FUNCT__ "TSGetKSPIterations"
5520 /*@
5521    TSGetKSPIterations - Gets the total number of linear iterations
5522    used by the time integrator.
5523 
5524    Not Collective
5525 
5526    Input Parameter:
5527 .  ts - TS context
5528 
5529    Output Parameter:
5530 .  lits - number of linear iterations
5531 
5532    Notes:
5533    This counter is reset to zero for each successive call to TSSolve().
5534 
5535    Level: intermediate
5536 
5537 .keywords: TS, get, number, linear, iterations
5538 
5539 .seealso:  TSGetSNESIterations(), SNESGetKSPIterations()
5540 @*/
5541 PetscErrorCode TSGetKSPIterations(TS ts,PetscInt *lits)
5542 {
5543   PetscFunctionBegin;
5544   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5545   PetscValidIntPointer(lits,2);
5546   *lits = ts->ksp_its;
5547   PetscFunctionReturn(0);
5548 }
5549 
5550 #undef __FUNCT__
5551 #define __FUNCT__ "TSGetStepRejections"
5552 /*@
5553    TSGetStepRejections - Gets the total number of rejected steps.
5554 
5555    Not Collective
5556 
5557    Input Parameter:
5558 .  ts - TS context
5559 
5560    Output Parameter:
5561 .  rejects - number of steps rejected
5562 
5563    Notes:
5564    This counter is reset to zero for each successive call to TSSolve().
5565 
5566    Level: intermediate
5567 
5568 .keywords: TS, get, number
5569 
5570 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetSNESFailures(), TSSetMaxSNESFailures(), TSSetErrorIfStepFails()
5571 @*/
5572 PetscErrorCode TSGetStepRejections(TS ts,PetscInt *rejects)
5573 {
5574   PetscFunctionBegin;
5575   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5576   PetscValidIntPointer(rejects,2);
5577   *rejects = ts->reject;
5578   PetscFunctionReturn(0);
5579 }
5580 
5581 #undef __FUNCT__
5582 #define __FUNCT__ "TSGetSNESFailures"
5583 /*@
5584    TSGetSNESFailures - Gets the total number of failed SNES solves
5585 
5586    Not Collective
5587 
5588    Input Parameter:
5589 .  ts - TS context
5590 
5591    Output Parameter:
5592 .  fails - number of failed nonlinear solves
5593 
5594    Notes:
5595    This counter is reset to zero for each successive call to TSSolve().
5596 
5597    Level: intermediate
5598 
5599 .keywords: TS, get, number
5600 
5601 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetStepRejections(), TSSetMaxSNESFailures()
5602 @*/
5603 PetscErrorCode TSGetSNESFailures(TS ts,PetscInt *fails)
5604 {
5605   PetscFunctionBegin;
5606   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5607   PetscValidIntPointer(fails,2);
5608   *fails = ts->num_snes_failures;
5609   PetscFunctionReturn(0);
5610 }
5611 
5612 #undef __FUNCT__
5613 #define __FUNCT__ "TSSetMaxStepRejections"
5614 /*@
5615    TSSetMaxStepRejections - Sets the maximum number of step rejections before a step fails
5616 
5617    Not Collective
5618 
5619    Input Parameter:
5620 +  ts - TS context
5621 -  rejects - maximum number of rejected steps, pass -1 for unlimited
5622 
5623    Notes:
5624    The counter is reset to zero for each step
5625 
5626    Options Database Key:
5627  .  -ts_max_reject - Maximum number of step rejections before a step fails
5628 
5629    Level: intermediate
5630 
5631 .keywords: TS, set, maximum, number
5632 
5633 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxSNESFailures(), TSGetStepRejections(), TSGetSNESFailures(), TSSetErrorIfStepFails(), TSGetConvergedReason()
5634 @*/
5635 PetscErrorCode TSSetMaxStepRejections(TS ts,PetscInt rejects)
5636 {
5637   PetscFunctionBegin;
5638   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5639   ts->max_reject = rejects;
5640   PetscFunctionReturn(0);
5641 }
5642 
5643 #undef __FUNCT__
5644 #define __FUNCT__ "TSSetMaxSNESFailures"
5645 /*@
5646    TSSetMaxSNESFailures - Sets the maximum number of failed SNES solves
5647 
5648    Not Collective
5649 
5650    Input Parameter:
5651 +  ts - TS context
5652 -  fails - maximum number of failed nonlinear solves, pass -1 for unlimited
5653 
5654    Notes:
5655    The counter is reset to zero for each successive call to TSSolve().
5656 
5657    Options Database Key:
5658  .  -ts_max_snes_failures - Maximum number of nonlinear solve failures
5659 
5660    Level: intermediate
5661 
5662 .keywords: TS, set, maximum, number
5663 
5664 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetStepRejections(), TSGetSNESFailures(), SNESGetConvergedReason(), TSGetConvergedReason()
5665 @*/
5666 PetscErrorCode TSSetMaxSNESFailures(TS ts,PetscInt fails)
5667 {
5668   PetscFunctionBegin;
5669   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5670   ts->max_snes_failures = fails;
5671   PetscFunctionReturn(0);
5672 }
5673 
5674 #undef __FUNCT__
5675 #define __FUNCT__ "TSSetErrorIfStepFails"
5676 /*@
5677    TSSetErrorIfStepFails - Error if no step succeeds
5678 
5679    Not Collective
5680 
5681    Input Parameter:
5682 +  ts - TS context
5683 -  err - PETSC_TRUE to error if no step succeeds, PETSC_FALSE to return without failure
5684 
5685    Options Database Key:
5686  .  -ts_error_if_step_fails - Error if no step succeeds
5687 
5688    Level: intermediate
5689 
5690 .keywords: TS, set, error
5691 
5692 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetStepRejections(), TSGetSNESFailures(), TSSetErrorIfStepFails(), TSGetConvergedReason()
5693 @*/
5694 PetscErrorCode TSSetErrorIfStepFails(TS ts,PetscBool err)
5695 {
5696   PetscFunctionBegin;
5697   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5698   ts->errorifstepfailed = err;
5699   PetscFunctionReturn(0);
5700 }
5701 
5702 #undef __FUNCT__
5703 #define __FUNCT__ "TSMonitorSolution"
5704 /*@C
5705    TSMonitorSolution - Monitors progress of the TS solvers by VecView() for the solution at each timestep. Normally the viewer is a binary file or a PetscDraw object
5706 
5707    Collective on TS
5708 
5709    Input Parameters:
5710 +  ts - the TS context
5711 .  step - current time-step
5712 .  ptime - current time
5713 .  u - current state
5714 -  vf - viewer and its format
5715 
5716    Level: intermediate
5717 
5718 .keywords: TS,  vector, monitor, view
5719 
5720 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
5721 @*/
5722 PetscErrorCode  TSMonitorSolution(TS ts,PetscInt step,PetscReal ptime,Vec u,PetscViewerAndFormat *vf)
5723 {
5724   PetscErrorCode ierr;
5725 
5726   PetscFunctionBegin;
5727   ierr = PetscViewerPushFormat(vf->viewer,vf->format);CHKERRQ(ierr);
5728   ierr = VecView(u,vf->viewer);CHKERRQ(ierr);
5729   ierr = PetscViewerPopFormat(vf->viewer);CHKERRQ(ierr);
5730   PetscFunctionReturn(0);
5731 }
5732 
5733 #undef __FUNCT__
5734 #define __FUNCT__ "TSMonitorSolutionVTK"
5735 /*@C
5736    TSMonitorSolutionVTK - Monitors progress of the TS solvers by VecView() for the solution at each timestep.
5737 
5738    Collective on TS
5739 
5740    Input Parameters:
5741 +  ts - the TS context
5742 .  step - current time-step
5743 .  ptime - current time
5744 .  u - current state
5745 -  filenametemplate - string containing a format specifier for the integer time step (e.g. %03D)
5746 
5747    Level: intermediate
5748 
5749    Notes:
5750    The VTK format does not allow writing multiple time steps in the same file, therefore a different file will be written for each time step.
5751    These are named according to the file name template.
5752 
5753    This function is normally passed as an argument to TSMonitorSet() along with TSMonitorSolutionVTKDestroy().
5754 
5755 .keywords: TS,  vector, monitor, view
5756 
5757 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
5758 @*/
5759 PetscErrorCode TSMonitorSolutionVTK(TS ts,PetscInt step,PetscReal ptime,Vec u,void *filenametemplate)
5760 {
5761   PetscErrorCode ierr;
5762   char           filename[PETSC_MAX_PATH_LEN];
5763   PetscViewer    viewer;
5764 
5765   PetscFunctionBegin;
5766   if (step < 0) PetscFunctionReturn(0); /* -1 indicates interpolated solution */
5767   ierr = PetscSNPrintf(filename,sizeof(filename),(const char*)filenametemplate,step);CHKERRQ(ierr);
5768   ierr = PetscViewerVTKOpen(PetscObjectComm((PetscObject)ts),filename,FILE_MODE_WRITE,&viewer);CHKERRQ(ierr);
5769   ierr = VecView(u,viewer);CHKERRQ(ierr);
5770   ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
5771   PetscFunctionReturn(0);
5772 }
5773 
5774 #undef __FUNCT__
5775 #define __FUNCT__ "TSMonitorSolutionVTKDestroy"
5776 /*@C
5777    TSMonitorSolutionVTKDestroy - Destroy context for monitoring
5778 
5779    Collective on TS
5780 
5781    Input Parameters:
5782 .  filenametemplate - string containing a format specifier for the integer time step (e.g. %03D)
5783 
5784    Level: intermediate
5785 
5786    Note:
5787    This function is normally passed to TSMonitorSet() along with TSMonitorSolutionVTK().
5788 
5789 .keywords: TS,  vector, monitor, view
5790 
5791 .seealso: TSMonitorSet(), TSMonitorSolutionVTK()
5792 @*/
5793 PetscErrorCode TSMonitorSolutionVTKDestroy(void *filenametemplate)
5794 {
5795   PetscErrorCode ierr;
5796 
5797   PetscFunctionBegin;
5798   ierr = PetscFree(*(char**)filenametemplate);CHKERRQ(ierr);
5799   PetscFunctionReturn(0);
5800 }
5801 
5802 #undef __FUNCT__
5803 #define __FUNCT__ "TSGetAdapt"
5804 /*@
5805    TSGetAdapt - Get the adaptive controller context for the current method
5806 
5807    Collective on TS if controller has not been created yet
5808 
5809    Input Arguments:
5810 .  ts - time stepping context
5811 
5812    Output Arguments:
5813 .  adapt - adaptive controller
5814 
5815    Level: intermediate
5816 
5817 .seealso: TSAdapt, TSAdaptSetType(), TSAdaptChoose()
5818 @*/
5819 PetscErrorCode TSGetAdapt(TS ts,TSAdapt *adapt)
5820 {
5821   PetscErrorCode ierr;
5822 
5823   PetscFunctionBegin;
5824   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5825   PetscValidPointer(adapt,2);
5826   if (!ts->adapt) {
5827     ierr = TSAdaptCreate(PetscObjectComm((PetscObject)ts),&ts->adapt);CHKERRQ(ierr);
5828     ierr = PetscLogObjectParent((PetscObject)ts,(PetscObject)ts->adapt);CHKERRQ(ierr);
5829     ierr = PetscObjectIncrementTabLevel((PetscObject)ts->adapt,(PetscObject)ts,1);CHKERRQ(ierr);
5830   }
5831   *adapt = ts->adapt;
5832   PetscFunctionReturn(0);
5833 }
5834 
5835 #undef __FUNCT__
5836 #define __FUNCT__ "TSSetTolerances"
5837 /*@
5838    TSSetTolerances - Set tolerances for local truncation error when using adaptive controller
5839 
5840    Logically Collective
5841 
5842    Input Arguments:
5843 +  ts - time integration context
5844 .  atol - scalar absolute tolerances, PETSC_DECIDE to leave current value
5845 .  vatol - vector of absolute tolerances or NULL, used in preference to atol if present
5846 .  rtol - scalar relative tolerances, PETSC_DECIDE to leave current value
5847 -  vrtol - vector of relative tolerances or NULL, used in preference to atol if present
5848 
5849    Options Database keys:
5850 +  -ts_rtol <rtol> - relative tolerance for local truncation error
5851 -  -ts_atol <atol> Absolute tolerance for local truncation error
5852 
5853    Notes:
5854    With PETSc's implicit schemes for DAE problems, the calculation of the local truncation error
5855    (LTE) includes both the differential and the algebraic variables. If one wants the LTE to be
5856    computed only for the differential or the algebraic part then this can be done using the vector of
5857    tolerances vatol. For example, by setting the tolerance vector with the desired tolerance for the
5858    differential part and infinity for the algebraic part, the LTE calculation will include only the
5859    differential variables.
5860 
5861    Level: beginner
5862 
5863 .seealso: TS, TSAdapt, TSVecNormWRMS(), TSGetTolerances()
5864 @*/
5865 PetscErrorCode TSSetTolerances(TS ts,PetscReal atol,Vec vatol,PetscReal rtol,Vec vrtol)
5866 {
5867   PetscErrorCode ierr;
5868 
5869   PetscFunctionBegin;
5870   if (atol != PETSC_DECIDE && atol != PETSC_DEFAULT) ts->atol = atol;
5871   if (vatol) {
5872     ierr = PetscObjectReference((PetscObject)vatol);CHKERRQ(ierr);
5873     ierr = VecDestroy(&ts->vatol);CHKERRQ(ierr);
5874     ts->vatol = vatol;
5875   }
5876   if (rtol != PETSC_DECIDE && rtol != PETSC_DEFAULT) ts->rtol = rtol;
5877   if (vrtol) {
5878     ierr = PetscObjectReference((PetscObject)vrtol);CHKERRQ(ierr);
5879     ierr = VecDestroy(&ts->vrtol);CHKERRQ(ierr);
5880     ts->vrtol = vrtol;
5881   }
5882   PetscFunctionReturn(0);
5883 }
5884 
5885 #undef __FUNCT__
5886 #define __FUNCT__ "TSGetTolerances"
5887 /*@
5888    TSGetTolerances - Get tolerances for local truncation error when using adaptive controller
5889 
5890    Logically Collective
5891 
5892    Input Arguments:
5893 .  ts - time integration context
5894 
5895    Output Arguments:
5896 +  atol - scalar absolute tolerances, NULL to ignore
5897 .  vatol - vector of absolute tolerances, NULL to ignore
5898 .  rtol - scalar relative tolerances, NULL to ignore
5899 -  vrtol - vector of relative tolerances, NULL to ignore
5900 
5901    Level: beginner
5902 
5903 .seealso: TS, TSAdapt, TSVecNormWRMS(), TSSetTolerances()
5904 @*/
5905 PetscErrorCode TSGetTolerances(TS ts,PetscReal *atol,Vec *vatol,PetscReal *rtol,Vec *vrtol)
5906 {
5907   PetscFunctionBegin;
5908   if (atol)  *atol  = ts->atol;
5909   if (vatol) *vatol = ts->vatol;
5910   if (rtol)  *rtol  = ts->rtol;
5911   if (vrtol) *vrtol = ts->vrtol;
5912   PetscFunctionReturn(0);
5913 }
5914 
5915 #undef __FUNCT__
5916 #define __FUNCT__ "TSErrorWeightedNorm2"
5917 /*@
5918    TSErrorWeightedNorm2 - compute a weighted 2-norm of the difference between two state vectors
5919 
5920    Collective on TS
5921 
5922    Input Arguments:
5923 +  ts - time stepping context
5924 .  U - state vector, usually ts->vec_sol
5925 -  Y - state vector to be compared to U
5926 
5927    Output Arguments:
5928 .  norm - weighted norm, a value of 1.0 is considered small
5929 
5930    Level: developer
5931 
5932 .seealso: TSErrorWeightedNorm(), TSErrorWeightedNormInfinity()
5933 @*/
5934 PetscErrorCode TSErrorWeightedNorm2(TS ts,Vec U,Vec Y,PetscReal *norm)
5935 {
5936   PetscErrorCode    ierr;
5937   PetscInt          i,n,N,rstart;
5938   const PetscScalar *u,*y;
5939   PetscReal         sum,gsum;
5940   PetscReal         tol;
5941 
5942   PetscFunctionBegin;
5943   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5944   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
5945   PetscValidHeaderSpecific(Y,VEC_CLASSID,3);
5946   PetscValidType(U,2);
5947   PetscValidType(Y,3);
5948   PetscCheckSameComm(U,2,Y,3);
5949   PetscValidPointer(norm,4);
5950   if (U == Y) SETERRQ(PetscObjectComm((PetscObject)U),PETSC_ERR_ARG_IDN,"U and Y cannot be the same vector");
5951 
5952   ierr = VecGetSize(U,&N);CHKERRQ(ierr);
5953   ierr = VecGetLocalSize(U,&n);CHKERRQ(ierr);
5954   ierr = VecGetOwnershipRange(U,&rstart,NULL);CHKERRQ(ierr);
5955   ierr = VecGetArrayRead(U,&u);CHKERRQ(ierr);
5956   ierr = VecGetArrayRead(Y,&y);CHKERRQ(ierr);
5957   sum  = 0.;
5958   if (ts->vatol && ts->vrtol) {
5959     const PetscScalar *atol,*rtol;
5960     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5961     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5962     for (i=0; i<n; i++) {
5963       tol = PetscRealPart(atol[i]) + PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5964       sum += PetscSqr(PetscAbsScalar(y[i] - u[i]) / tol);
5965     }
5966     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5967     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5968   } else if (ts->vatol) {       /* vector atol, scalar rtol */
5969     const PetscScalar *atol;
5970     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5971     for (i=0; i<n; i++) {
5972       tol = PetscRealPart(atol[i]) + ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5973       sum += PetscSqr(PetscAbsScalar(y[i] - u[i]) / tol);
5974     }
5975     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5976   } else if (ts->vrtol) {       /* scalar atol, vector rtol */
5977     const PetscScalar *rtol;
5978     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5979     for (i=0; i<n; i++) {
5980       tol = ts->atol + PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5981       sum += PetscSqr(PetscAbsScalar(y[i] - u[i]) / tol);
5982     }
5983     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5984   } else {                      /* scalar atol, scalar rtol */
5985     for (i=0; i<n; i++) {
5986       tol = ts->atol + ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5987       sum += PetscSqr(PetscAbsScalar(y[i] - u[i]) / tol);
5988     }
5989   }
5990   ierr = VecRestoreArrayRead(U,&u);CHKERRQ(ierr);
5991   ierr = VecRestoreArrayRead(Y,&y);CHKERRQ(ierr);
5992 
5993   ierr  = MPIU_Allreduce(&sum,&gsum,1,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
5994   *norm = PetscSqrtReal(gsum / N);
5995 
5996   if (PetscIsInfOrNanScalar(*norm)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
5997   PetscFunctionReturn(0);
5998 }
5999 
6000 #undef __FUNCT__
6001 #define __FUNCT__ "TSErrorWeightedNormInfinity"
6002 /*@
6003    TSErrorWeightedNormInfinity - compute a weighted infinity-norm of the difference between two state vectors
6004 
6005    Collective on TS
6006 
6007    Input Arguments:
6008 +  ts - time stepping context
6009 .  U - state vector, usually ts->vec_sol
6010 -  Y - state vector to be compared to U
6011 
6012    Output Arguments:
6013 .  norm - weighted norm, a value of 1.0 is considered small
6014 
6015    Level: developer
6016 
6017 .seealso: TSErrorWeightedNorm(), TSErrorWeightedNorm2()
6018 @*/
6019 PetscErrorCode TSErrorWeightedNormInfinity(TS ts,Vec U,Vec Y,PetscReal *norm)
6020 {
6021   PetscErrorCode    ierr;
6022   PetscInt          i,n,N,rstart,k;
6023   const PetscScalar *u,*y;
6024   PetscReal         max,gmax;
6025   PetscReal         tol;
6026 
6027   PetscFunctionBegin;
6028   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
6029   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
6030   PetscValidHeaderSpecific(Y,VEC_CLASSID,3);
6031   PetscValidType(U,2);
6032   PetscValidType(Y,3);
6033   PetscCheckSameComm(U,2,Y,3);
6034   PetscValidPointer(norm,4);
6035   if (U == Y) SETERRQ(PetscObjectComm((PetscObject)U),PETSC_ERR_ARG_IDN,"U and Y cannot be the same vector");
6036 
6037   ierr = VecGetSize(U,&N);CHKERRQ(ierr);
6038   ierr = VecGetLocalSize(U,&n);CHKERRQ(ierr);
6039   ierr = VecGetOwnershipRange(U,&rstart,NULL);CHKERRQ(ierr);
6040   ierr = VecGetArrayRead(U,&u);CHKERRQ(ierr);
6041   ierr = VecGetArrayRead(Y,&y);CHKERRQ(ierr);
6042   if (ts->vatol && ts->vrtol) {
6043     const PetscScalar *atol,*rtol;
6044     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
6045     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
6046     k = 0;
6047     tol = PetscRealPart(atol[k]) + PetscRealPart(rtol[k]) * PetscMax(PetscAbsScalar(u[k]),PetscAbsScalar(y[k]));
6048     max = PetscAbsScalar(y[k] - u[k]) / tol;
6049     for (i=1; i<n; i++) {
6050       tol = PetscRealPart(atol[i]) + PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
6051       max = PetscMax(max,PetscAbsScalar(y[i] - u[i]) / tol);
6052     }
6053     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
6054     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
6055   } else if (ts->vatol) {       /* vector atol, scalar rtol */
6056     const PetscScalar *atol;
6057     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
6058     k = 0;
6059     tol = PetscRealPart(atol[k]) + ts->rtol * PetscMax(PetscAbsScalar(u[k]),PetscAbsScalar(y[k]));
6060     max = PetscAbsScalar(y[k] - u[k]) / tol;
6061     for (i=1; i<n; i++) {
6062       tol = PetscRealPart(atol[i]) + ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
6063       max = PetscMax(max,PetscAbsScalar(y[i] - u[i]) / tol);
6064     }
6065     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
6066   } else if (ts->vrtol) {       /* scalar atol, vector rtol */
6067     const PetscScalar *rtol;
6068     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
6069     k = 0;
6070     tol = ts->atol + PetscRealPart(rtol[k]) * PetscMax(PetscAbsScalar(u[k]),PetscAbsScalar(y[k]));
6071     max = PetscAbsScalar(y[k] - u[k]) / tol;
6072     for (i=1; i<n; i++) {
6073       tol = ts->atol + PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
6074       max = PetscMax(max,PetscAbsScalar(y[i] - u[i]) / tol);
6075     }
6076     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
6077   } else {                      /* scalar atol, scalar rtol */
6078     k = 0;
6079     tol = ts->atol + ts->rtol * PetscMax(PetscAbsScalar(u[k]),PetscAbsScalar(y[k]));
6080     max = PetscAbsScalar(y[k] - u[k]) / tol;
6081     for (i=1; i<n; i++) {
6082       tol = ts->atol + ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
6083       max = PetscMax(max,PetscAbsScalar(y[i] - u[i]) / tol);
6084     }
6085   }
6086   ierr = VecRestoreArrayRead(U,&u);CHKERRQ(ierr);
6087   ierr = VecRestoreArrayRead(Y,&y);CHKERRQ(ierr);
6088 
6089   ierr  = MPIU_Allreduce(&max,&gmax,1,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
6090   *norm = gmax;
6091 
6092   if (PetscIsInfOrNanScalar(*norm)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
6093   PetscFunctionReturn(0);
6094 }
6095 
6096 #undef __FUNCT__
6097 #define __FUNCT__ "TSErrorWeightedNorm"
6098 /*@
6099    TSErrorWeightedNorm - compute a weighted norm of the difference between two state vectors
6100 
6101    Collective on TS
6102 
6103    Input Arguments:
6104 +  ts - time stepping context
6105 .  U - state vector, usually ts->vec_sol
6106 .  Y - state vector to be compared to U
6107 -  wnormtype - norm type, either NORM_2 or NORM_INFINITY
6108 
6109    Output Arguments:
6110 .  norm - weighted norm, a value of 1.0 is considered small
6111 
6112 
6113    Options Database Keys:
6114 .  -ts_adapt_wnormtype <wnormtype> - 2, INFINITY
6115 
6116    Level: developer
6117 
6118 .seealso: TSErrorWeightedNormInfinity(), TSErrorWeightedNorm2()
6119 @*/
6120 PetscErrorCode TSErrorWeightedNorm(TS ts,Vec U,Vec Y,NormType wnormtype,PetscReal *norm)
6121 {
6122   PetscErrorCode ierr;
6123 
6124   PetscFunctionBegin;
6125   if (wnormtype == NORM_2) {
6126     ierr = TSErrorWeightedNorm2(ts,U,Y,norm);CHKERRQ(ierr);
6127   } else if(wnormtype == NORM_INFINITY) {
6128     ierr = TSErrorWeightedNormInfinity(ts,U,Y,norm);CHKERRQ(ierr);
6129   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support for norm type %s",NormTypes[wnormtype]);
6130   PetscFunctionReturn(0);
6131 }
6132 
6133 #undef __FUNCT__
6134 #define __FUNCT__ "TSSetCFLTimeLocal"
6135 /*@
6136    TSSetCFLTimeLocal - Set the local CFL constraint relative to forward Euler
6137 
6138    Logically Collective on TS
6139 
6140    Input Arguments:
6141 +  ts - time stepping context
6142 -  cfltime - maximum stable time step if using forward Euler (value can be different on each process)
6143 
6144    Note:
6145    After calling this function, the global CFL time can be obtained by calling TSGetCFLTime()
6146 
6147    Level: intermediate
6148 
6149 .seealso: TSGetCFLTime(), TSADAPTCFL
6150 @*/
6151 PetscErrorCode TSSetCFLTimeLocal(TS ts,PetscReal cfltime)
6152 {
6153   PetscFunctionBegin;
6154   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
6155   ts->cfltime_local = cfltime;
6156   ts->cfltime       = -1.;
6157   PetscFunctionReturn(0);
6158 }
6159 
6160 #undef __FUNCT__
6161 #define __FUNCT__ "TSGetCFLTime"
6162 /*@
6163    TSGetCFLTime - Get the maximum stable time step according to CFL criteria applied to forward Euler
6164 
6165    Collective on TS
6166 
6167    Input Arguments:
6168 .  ts - time stepping context
6169 
6170    Output Arguments:
6171 .  cfltime - maximum stable time step for forward Euler
6172 
6173    Level: advanced
6174 
6175 .seealso: TSSetCFLTimeLocal()
6176 @*/
6177 PetscErrorCode TSGetCFLTime(TS ts,PetscReal *cfltime)
6178 {
6179   PetscErrorCode ierr;
6180 
6181   PetscFunctionBegin;
6182   if (ts->cfltime < 0) {
6183     ierr = MPIU_Allreduce(&ts->cfltime_local,&ts->cfltime,1,MPIU_REAL,MPIU_MIN,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
6184   }
6185   *cfltime = ts->cfltime;
6186   PetscFunctionReturn(0);
6187 }
6188 
6189 #undef __FUNCT__
6190 #define __FUNCT__ "TSVISetVariableBounds"
6191 /*@
6192    TSVISetVariableBounds - Sets the lower and upper bounds for the solution vector. xl <= x <= xu
6193 
6194    Input Parameters:
6195 .  ts   - the TS context.
6196 .  xl   - lower bound.
6197 .  xu   - upper bound.
6198 
6199    Notes:
6200    If this routine is not called then the lower and upper bounds are set to
6201    PETSC_NINFINITY and PETSC_INFINITY respectively during SNESSetUp().
6202 
6203    Level: advanced
6204 
6205 @*/
6206 PetscErrorCode TSVISetVariableBounds(TS ts, Vec xl, Vec xu)
6207 {
6208   PetscErrorCode ierr;
6209   SNES           snes;
6210 
6211   PetscFunctionBegin;
6212   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
6213   ierr = SNESVISetVariableBounds(snes,xl,xu);CHKERRQ(ierr);
6214   PetscFunctionReturn(0);
6215 }
6216 
6217 #if defined(PETSC_HAVE_MATLAB_ENGINE)
6218 #include <mex.h>
6219 
6220 typedef struct {char *funcname; mxArray *ctx;} TSMatlabContext;
6221 
6222 #undef __FUNCT__
6223 #define __FUNCT__ "TSComputeFunction_Matlab"
6224 /*
6225    TSComputeFunction_Matlab - Calls the function that has been set with
6226                          TSSetFunctionMatlab().
6227 
6228    Collective on TS
6229 
6230    Input Parameters:
6231 +  snes - the TS context
6232 -  u - input vector
6233 
6234    Output Parameter:
6235 .  y - function vector, as set by TSSetFunction()
6236 
6237    Notes:
6238    TSComputeFunction() is typically used within nonlinear solvers
6239    implementations, so most users would not generally call this routine
6240    themselves.
6241 
6242    Level: developer
6243 
6244 .keywords: TS, nonlinear, compute, function
6245 
6246 .seealso: TSSetFunction(), TSGetFunction()
6247 */
6248 PetscErrorCode  TSComputeFunction_Matlab(TS snes,PetscReal time,Vec u,Vec udot,Vec y, void *ctx)
6249 {
6250   PetscErrorCode  ierr;
6251   TSMatlabContext *sctx = (TSMatlabContext*)ctx;
6252   int             nlhs  = 1,nrhs = 7;
6253   mxArray         *plhs[1],*prhs[7];
6254   long long int   lx = 0,lxdot = 0,ly = 0,ls = 0;
6255 
6256   PetscFunctionBegin;
6257   PetscValidHeaderSpecific(snes,TS_CLASSID,1);
6258   PetscValidHeaderSpecific(u,VEC_CLASSID,3);
6259   PetscValidHeaderSpecific(udot,VEC_CLASSID,4);
6260   PetscValidHeaderSpecific(y,VEC_CLASSID,5);
6261   PetscCheckSameComm(snes,1,u,3);
6262   PetscCheckSameComm(snes,1,y,5);
6263 
6264   ierr = PetscMemcpy(&ls,&snes,sizeof(snes));CHKERRQ(ierr);
6265   ierr = PetscMemcpy(&lx,&u,sizeof(u));CHKERRQ(ierr);
6266   ierr = PetscMemcpy(&lxdot,&udot,sizeof(udot));CHKERRQ(ierr);
6267   ierr = PetscMemcpy(&ly,&y,sizeof(u));CHKERRQ(ierr);
6268 
6269   prhs[0] =  mxCreateDoubleScalar((double)ls);
6270   prhs[1] =  mxCreateDoubleScalar(time);
6271   prhs[2] =  mxCreateDoubleScalar((double)lx);
6272   prhs[3] =  mxCreateDoubleScalar((double)lxdot);
6273   prhs[4] =  mxCreateDoubleScalar((double)ly);
6274   prhs[5] =  mxCreateString(sctx->funcname);
6275   prhs[6] =  sctx->ctx;
6276   ierr    =  mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscTSComputeFunctionInternal");CHKERRQ(ierr);
6277   ierr    =  mxGetScalar(plhs[0]);CHKERRQ(ierr);
6278   mxDestroyArray(prhs[0]);
6279   mxDestroyArray(prhs[1]);
6280   mxDestroyArray(prhs[2]);
6281   mxDestroyArray(prhs[3]);
6282   mxDestroyArray(prhs[4]);
6283   mxDestroyArray(prhs[5]);
6284   mxDestroyArray(plhs[0]);
6285   PetscFunctionReturn(0);
6286 }
6287 
6288 
6289 #undef __FUNCT__
6290 #define __FUNCT__ "TSSetFunctionMatlab"
6291 /*
6292    TSSetFunctionMatlab - Sets the function evaluation routine and function
6293    vector for use by the TS routines in solving ODEs
6294    equations from MATLAB. Here the function is a string containing the name of a MATLAB function
6295 
6296    Logically Collective on TS
6297 
6298    Input Parameters:
6299 +  ts - the TS context
6300 -  func - function evaluation routine
6301 
6302    Calling sequence of func:
6303 $    func (TS ts,PetscReal time,Vec u,Vec udot,Vec f,void *ctx);
6304 
6305    Level: beginner
6306 
6307 .keywords: TS, nonlinear, set, function
6308 
6309 .seealso: TSGetFunction(), TSComputeFunction(), TSSetJacobian(), TSSetFunction()
6310 */
6311 PetscErrorCode  TSSetFunctionMatlab(TS ts,const char *func,mxArray *ctx)
6312 {
6313   PetscErrorCode  ierr;
6314   TSMatlabContext *sctx;
6315 
6316   PetscFunctionBegin;
6317   /* currently sctx is memory bleed */
6318   ierr = PetscNew(&sctx);CHKERRQ(ierr);
6319   ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr);
6320   /*
6321      This should work, but it doesn't
6322   sctx->ctx = ctx;
6323   mexMakeArrayPersistent(sctx->ctx);
6324   */
6325   sctx->ctx = mxDuplicateArray(ctx);
6326 
6327   ierr = TSSetIFunction(ts,NULL,TSComputeFunction_Matlab,sctx);CHKERRQ(ierr);
6328   PetscFunctionReturn(0);
6329 }
6330 
6331 #undef __FUNCT__
6332 #define __FUNCT__ "TSComputeJacobian_Matlab"
6333 /*
6334    TSComputeJacobian_Matlab - Calls the function that has been set with
6335                          TSSetJacobianMatlab().
6336 
6337    Collective on TS
6338 
6339    Input Parameters:
6340 +  ts - the TS context
6341 .  u - input vector
6342 .  A, B - the matrices
6343 -  ctx - user context
6344 
6345    Level: developer
6346 
6347 .keywords: TS, nonlinear, compute, function
6348 
6349 .seealso: TSSetFunction(), TSGetFunction()
6350 @*/
6351 PetscErrorCode  TSComputeJacobian_Matlab(TS ts,PetscReal time,Vec u,Vec udot,PetscReal shift,Mat A,Mat B,void *ctx)
6352 {
6353   PetscErrorCode  ierr;
6354   TSMatlabContext *sctx = (TSMatlabContext*)ctx;
6355   int             nlhs  = 2,nrhs = 9;
6356   mxArray         *plhs[2],*prhs[9];
6357   long long int   lx = 0,lxdot = 0,lA = 0,ls = 0, lB = 0;
6358 
6359   PetscFunctionBegin;
6360   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
6361   PetscValidHeaderSpecific(u,VEC_CLASSID,3);
6362 
6363   /* call Matlab function in ctx with arguments u and y */
6364 
6365   ierr = PetscMemcpy(&ls,&ts,sizeof(ts));CHKERRQ(ierr);
6366   ierr = PetscMemcpy(&lx,&u,sizeof(u));CHKERRQ(ierr);
6367   ierr = PetscMemcpy(&lxdot,&udot,sizeof(u));CHKERRQ(ierr);
6368   ierr = PetscMemcpy(&lA,A,sizeof(u));CHKERRQ(ierr);
6369   ierr = PetscMemcpy(&lB,B,sizeof(u));CHKERRQ(ierr);
6370 
6371   prhs[0] =  mxCreateDoubleScalar((double)ls);
6372   prhs[1] =  mxCreateDoubleScalar((double)time);
6373   prhs[2] =  mxCreateDoubleScalar((double)lx);
6374   prhs[3] =  mxCreateDoubleScalar((double)lxdot);
6375   prhs[4] =  mxCreateDoubleScalar((double)shift);
6376   prhs[5] =  mxCreateDoubleScalar((double)lA);
6377   prhs[6] =  mxCreateDoubleScalar((double)lB);
6378   prhs[7] =  mxCreateString(sctx->funcname);
6379   prhs[8] =  sctx->ctx;
6380   ierr    =  mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscTSComputeJacobianInternal");CHKERRQ(ierr);
6381   ierr    =  mxGetScalar(plhs[0]);CHKERRQ(ierr);
6382   mxDestroyArray(prhs[0]);
6383   mxDestroyArray(prhs[1]);
6384   mxDestroyArray(prhs[2]);
6385   mxDestroyArray(prhs[3]);
6386   mxDestroyArray(prhs[4]);
6387   mxDestroyArray(prhs[5]);
6388   mxDestroyArray(prhs[6]);
6389   mxDestroyArray(prhs[7]);
6390   mxDestroyArray(plhs[0]);
6391   mxDestroyArray(plhs[1]);
6392   PetscFunctionReturn(0);
6393 }
6394 
6395 
6396 #undef __FUNCT__
6397 #define __FUNCT__ "TSSetJacobianMatlab"
6398 /*
6399    TSSetJacobianMatlab - Sets the Jacobian function evaluation routine and two empty Jacobian matrices
6400    vector for use by the TS routines in solving ODEs from MATLAB. Here the function is a string containing the name of a MATLAB function
6401 
6402    Logically Collective on TS
6403 
6404    Input Parameters:
6405 +  ts - the TS context
6406 .  A,B - Jacobian matrices
6407 .  func - function evaluation routine
6408 -  ctx - user context
6409 
6410    Calling sequence of func:
6411 $    flag = func (TS ts,PetscReal time,Vec u,Vec udot,Mat A,Mat B,void *ctx);
6412 
6413 
6414    Level: developer
6415 
6416 .keywords: TS, nonlinear, set, function
6417 
6418 .seealso: TSGetFunction(), TSComputeFunction(), TSSetJacobian(), TSSetFunction()
6419 */
6420 PetscErrorCode  TSSetJacobianMatlab(TS ts,Mat A,Mat B,const char *func,mxArray *ctx)
6421 {
6422   PetscErrorCode  ierr;
6423   TSMatlabContext *sctx;
6424 
6425   PetscFunctionBegin;
6426   /* currently sctx is memory bleed */
6427   ierr = PetscNew(&sctx);CHKERRQ(ierr);
6428   ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr);
6429   /*
6430      This should work, but it doesn't
6431   sctx->ctx = ctx;
6432   mexMakeArrayPersistent(sctx->ctx);
6433   */
6434   sctx->ctx = mxDuplicateArray(ctx);
6435 
6436   ierr = TSSetIJacobian(ts,A,B,TSComputeJacobian_Matlab,sctx);CHKERRQ(ierr);
6437   PetscFunctionReturn(0);
6438 }
6439 
6440 #undef __FUNCT__
6441 #define __FUNCT__ "TSMonitor_Matlab"
6442 /*
6443    TSMonitor_Matlab - Calls the function that has been set with TSMonitorSetMatlab().
6444 
6445    Collective on TS
6446 
6447 .seealso: TSSetFunction(), TSGetFunction()
6448 @*/
6449 PetscErrorCode  TSMonitor_Matlab(TS ts,PetscInt it, PetscReal time,Vec u, void *ctx)
6450 {
6451   PetscErrorCode  ierr;
6452   TSMatlabContext *sctx = (TSMatlabContext*)ctx;
6453   int             nlhs  = 1,nrhs = 6;
6454   mxArray         *plhs[1],*prhs[6];
6455   long long int   lx = 0,ls = 0;
6456 
6457   PetscFunctionBegin;
6458   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
6459   PetscValidHeaderSpecific(u,VEC_CLASSID,4);
6460 
6461   ierr = PetscMemcpy(&ls,&ts,sizeof(ts));CHKERRQ(ierr);
6462   ierr = PetscMemcpy(&lx,&u,sizeof(u));CHKERRQ(ierr);
6463 
6464   prhs[0] =  mxCreateDoubleScalar((double)ls);
6465   prhs[1] =  mxCreateDoubleScalar((double)it);
6466   prhs[2] =  mxCreateDoubleScalar((double)time);
6467   prhs[3] =  mxCreateDoubleScalar((double)lx);
6468   prhs[4] =  mxCreateString(sctx->funcname);
6469   prhs[5] =  sctx->ctx;
6470   ierr    =  mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscTSMonitorInternal");CHKERRQ(ierr);
6471   ierr    =  mxGetScalar(plhs[0]);CHKERRQ(ierr);
6472   mxDestroyArray(prhs[0]);
6473   mxDestroyArray(prhs[1]);
6474   mxDestroyArray(prhs[2]);
6475   mxDestroyArray(prhs[3]);
6476   mxDestroyArray(prhs[4]);
6477   mxDestroyArray(plhs[0]);
6478   PetscFunctionReturn(0);
6479 }
6480 
6481 
6482 #undef __FUNCT__
6483 #define __FUNCT__ "TSMonitorSetMatlab"
6484 /*
6485    TSMonitorSetMatlab - Sets the monitor function from Matlab
6486 
6487    Level: developer
6488 
6489 .keywords: TS, nonlinear, set, function
6490 
6491 .seealso: TSGetFunction(), TSComputeFunction(), TSSetJacobian(), TSSetFunction()
6492 */
6493 PetscErrorCode  TSMonitorSetMatlab(TS ts,const char *func,mxArray *ctx)
6494 {
6495   PetscErrorCode  ierr;
6496   TSMatlabContext *sctx;
6497 
6498   PetscFunctionBegin;
6499   /* currently sctx is memory bleed */
6500   ierr = PetscNew(&sctx);CHKERRQ(ierr);
6501   ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr);
6502   /*
6503      This should work, but it doesn't
6504   sctx->ctx = ctx;
6505   mexMakeArrayPersistent(sctx->ctx);
6506   */
6507   sctx->ctx = mxDuplicateArray(ctx);
6508 
6509   ierr = TSMonitorSet(ts,TSMonitor_Matlab,sctx,NULL);CHKERRQ(ierr);
6510   PetscFunctionReturn(0);
6511 }
6512 #endif
6513 
6514 #undef __FUNCT__
6515 #define __FUNCT__ "TSMonitorLGSolution"
6516 /*@C
6517    TSMonitorLGSolution - Monitors progress of the TS solvers by plotting each component of the solution vector
6518        in a time based line graph
6519 
6520    Collective on TS
6521 
6522    Input Parameters:
6523 +  ts - the TS context
6524 .  step - current time-step
6525 .  ptime - current time
6526 .  u - current solution
6527 -  dctx - the TSMonitorLGCtx object that contains all the options for the monitoring, this is created with TSMonitorLGCtxCreate()
6528 
6529    Options Database:
6530 .   -ts_monitor_lg_solution_variables
6531 
6532    Level: intermediate
6533 
6534    Notes: Each process in a parallel run displays its component solutions in a separate window
6535 
6536 .keywords: TS,  vector, monitor, view
6537 
6538 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGCtxCreate(), TSMonitorLGCtxSetVariableNames(), TSMonitorLGCtxGetVariableNames(),
6539            TSMonitorLGSetVariableNames(), TSMonitorLGGetVariableNames(), TSMonitorLGSetDisplayVariables(), TSMonitorLGCtxSetDisplayVariables(),
6540            TSMonitorLGCtxSetTransform(), TSMonitorLGSetTransform(), TSMonitorLGError(), TSMonitorLGSNESIterations(), TSMonitorLGKSPIterations(),
6541            TSMonitorEnvelopeCtxCreate(), TSMonitorEnvelopeGetBounds(), TSMonitorEnvelopeCtxDestroy(), TSMonitorEnvelop()
6542 @*/
6543 PetscErrorCode  TSMonitorLGSolution(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dctx)
6544 {
6545   PetscErrorCode    ierr;
6546   TSMonitorLGCtx    ctx = (TSMonitorLGCtx)dctx;
6547   const PetscScalar *yy;
6548   Vec               v;
6549 
6550   PetscFunctionBegin;
6551   if (step < 0) PetscFunctionReturn(0); /* -1 indicates interpolated solution */
6552   if (!step) {
6553     PetscDrawAxis axis;
6554     PetscInt      dim;
6555     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
6556     ierr = PetscDrawAxisSetLabels(axis,"Solution as function of time","Time","Solution");CHKERRQ(ierr);
6557     if (!ctx->names) {
6558       PetscBool flg;
6559       /* user provides names of variables to plot but no names has been set so assume names are integer values */
6560       ierr = PetscOptionsHasName(((PetscObject)ts)->options,((PetscObject)ts)->prefix,"-ts_monitor_lg_solution_variables",&flg);CHKERRQ(ierr);
6561       if (flg) {
6562         PetscInt i,n;
6563         char     **names;
6564         ierr = VecGetSize(u,&n);CHKERRQ(ierr);
6565         ierr = PetscMalloc1(n+1,&names);CHKERRQ(ierr);
6566         for (i=0; i<n; i++) {
6567           ierr = PetscMalloc1(5,&names[i]);CHKERRQ(ierr);
6568           ierr = PetscSNPrintf(names[i],5,"%D",i);CHKERRQ(ierr);
6569         }
6570         names[n] = NULL;
6571         ctx->names = names;
6572       }
6573     }
6574     if (ctx->names && !ctx->displaynames) {
6575       char      **displaynames;
6576       PetscBool flg;
6577       ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
6578       ierr = PetscMalloc1(dim+1,&displaynames);CHKERRQ(ierr);
6579       ierr = PetscMemzero(displaynames,(dim+1)*sizeof(char*));CHKERRQ(ierr);
6580       ierr = PetscOptionsGetStringArray(((PetscObject)ts)->options,((PetscObject)ts)->prefix,"-ts_monitor_lg_solution_variables",displaynames,&dim,&flg);CHKERRQ(ierr);
6581       if (flg) {
6582         ierr = TSMonitorLGCtxSetDisplayVariables(ctx,(const char *const *)displaynames);CHKERRQ(ierr);
6583       }
6584       ierr = PetscStrArrayDestroy(&displaynames);CHKERRQ(ierr);
6585     }
6586     if (ctx->displaynames) {
6587       ierr = PetscDrawLGSetDimension(ctx->lg,ctx->ndisplayvariables);CHKERRQ(ierr);
6588       ierr = PetscDrawLGSetLegend(ctx->lg,(const char *const *)ctx->displaynames);CHKERRQ(ierr);
6589     } else if (ctx->names) {
6590       ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
6591       ierr = PetscDrawLGSetDimension(ctx->lg,dim);CHKERRQ(ierr);
6592       ierr = PetscDrawLGSetLegend(ctx->lg,(const char *const *)ctx->names);CHKERRQ(ierr);
6593     } else {
6594       ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
6595       ierr = PetscDrawLGSetDimension(ctx->lg,dim);CHKERRQ(ierr);
6596     }
6597     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
6598   }
6599 
6600   if (!ctx->transform) v = u;
6601   else {ierr = (*ctx->transform)(ctx->transformctx,u,&v);CHKERRQ(ierr);}
6602   ierr = VecGetArrayRead(v,&yy);CHKERRQ(ierr);
6603   if (ctx->displaynames) {
6604     PetscInt i;
6605     for (i=0; i<ctx->ndisplayvariables; i++)
6606       ctx->displayvalues[i] = PetscRealPart(yy[ctx->displayvariables[i]]);
6607     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,ctx->displayvalues);CHKERRQ(ierr);
6608   } else {
6609 #if defined(PETSC_USE_COMPLEX)
6610     PetscInt  i,n;
6611     PetscReal *yreal;
6612     ierr = VecGetLocalSize(v,&n);CHKERRQ(ierr);
6613     ierr = PetscMalloc1(n,&yreal);CHKERRQ(ierr);
6614     for (i=0; i<n; i++) yreal[i] = PetscRealPart(yy[i]);
6615     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yreal);CHKERRQ(ierr);
6616     ierr = PetscFree(yreal);CHKERRQ(ierr);
6617 #else
6618     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yy);CHKERRQ(ierr);
6619 #endif
6620   }
6621   ierr = VecRestoreArrayRead(v,&yy);CHKERRQ(ierr);
6622   if (ctx->transform) {ierr = VecDestroy(&v);CHKERRQ(ierr);}
6623 
6624   if (((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason)) {
6625     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
6626     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
6627   }
6628   PetscFunctionReturn(0);
6629 }
6630 
6631 
6632 #undef __FUNCT__
6633 #define __FUNCT__ "TSMonitorLGSetVariableNames"
6634 /*@C
6635    TSMonitorLGSetVariableNames - Sets the name of each component in the solution vector so that it may be displayed in the plot
6636 
6637    Collective on TS
6638 
6639    Input Parameters:
6640 +  ts - the TS context
6641 -  names - the names of the components, final string must be NULL
6642 
6643    Level: intermediate
6644 
6645    Notes: If the TS object does not have a TSMonitorLGCtx associated with it then this function is ignored
6646 
6647 .keywords: TS,  vector, monitor, view
6648 
6649 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetDisplayVariables(), TSMonitorLGCtxSetVariableNames()
6650 @*/
6651 PetscErrorCode  TSMonitorLGSetVariableNames(TS ts,const char * const *names)
6652 {
6653   PetscErrorCode    ierr;
6654   PetscInt          i;
6655 
6656   PetscFunctionBegin;
6657   for (i=0; i<ts->numbermonitors; i++) {
6658     if (ts->monitor[i] == TSMonitorLGSolution) {
6659       ierr = TSMonitorLGCtxSetVariableNames((TSMonitorLGCtx)ts->monitorcontext[i],names);CHKERRQ(ierr);
6660       break;
6661     }
6662   }
6663   PetscFunctionReturn(0);
6664 }
6665 
6666 #undef __FUNCT__
6667 #define __FUNCT__ "TSMonitorLGCtxSetVariableNames"
6668 /*@C
6669    TSMonitorLGCtxSetVariableNames - Sets the name of each component in the solution vector so that it may be displayed in the plot
6670 
6671    Collective on TS
6672 
6673    Input Parameters:
6674 +  ts - the TS context
6675 -  names - the names of the components, final string must be NULL
6676 
6677    Level: intermediate
6678 
6679 .keywords: TS,  vector, monitor, view
6680 
6681 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetDisplayVariables(), TSMonitorLGSetVariableNames()
6682 @*/
6683 PetscErrorCode  TSMonitorLGCtxSetVariableNames(TSMonitorLGCtx ctx,const char * const *names)
6684 {
6685   PetscErrorCode    ierr;
6686 
6687   PetscFunctionBegin;
6688   ierr = PetscStrArrayDestroy(&ctx->names);CHKERRQ(ierr);
6689   ierr = PetscStrArrayallocpy(names,&ctx->names);CHKERRQ(ierr);
6690   PetscFunctionReturn(0);
6691 }
6692 
6693 #undef __FUNCT__
6694 #define __FUNCT__ "TSMonitorLGGetVariableNames"
6695 /*@C
6696    TSMonitorLGGetVariableNames - Gets the name of each component in the solution vector so that it may be displayed in the plot
6697 
6698    Collective on TS
6699 
6700    Input Parameter:
6701 .  ts - the TS context
6702 
6703    Output Parameter:
6704 .  names - the names of the components, final string must be NULL
6705 
6706    Level: intermediate
6707 
6708    Notes: If the TS object does not have a TSMonitorLGCtx associated with it then this function is ignored
6709 
6710 .keywords: TS,  vector, monitor, view
6711 
6712 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetDisplayVariables()
6713 @*/
6714 PetscErrorCode  TSMonitorLGGetVariableNames(TS ts,const char *const **names)
6715 {
6716   PetscInt       i;
6717 
6718   PetscFunctionBegin;
6719   *names = NULL;
6720   for (i=0; i<ts->numbermonitors; i++) {
6721     if (ts->monitor[i] == TSMonitorLGSolution) {
6722       TSMonitorLGCtx  ctx = (TSMonitorLGCtx) ts->monitorcontext[i];
6723       *names = (const char *const *)ctx->names;
6724       break;
6725     }
6726   }
6727   PetscFunctionReturn(0);
6728 }
6729 
6730 #undef __FUNCT__
6731 #define __FUNCT__ "TSMonitorLGCtxSetDisplayVariables"
6732 /*@C
6733    TSMonitorLGCtxSetDisplayVariables - Sets the variables that are to be display in the monitor
6734 
6735    Collective on TS
6736 
6737    Input Parameters:
6738 +  ctx - the TSMonitorLG context
6739 .  displaynames - the names of the components, final string must be NULL
6740 
6741    Level: intermediate
6742 
6743 .keywords: TS,  vector, monitor, view
6744 
6745 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetVariableNames()
6746 @*/
6747 PetscErrorCode  TSMonitorLGCtxSetDisplayVariables(TSMonitorLGCtx ctx,const char * const *displaynames)
6748 {
6749   PetscInt          j = 0,k;
6750   PetscErrorCode    ierr;
6751 
6752   PetscFunctionBegin;
6753   if (!ctx->names) PetscFunctionReturn(0);
6754   ierr = PetscStrArrayDestroy(&ctx->displaynames);CHKERRQ(ierr);
6755   ierr = PetscStrArrayallocpy(displaynames,&ctx->displaynames);CHKERRQ(ierr);
6756   while (displaynames[j]) j++;
6757   ctx->ndisplayvariables = j;
6758   ierr = PetscMalloc1(ctx->ndisplayvariables,&ctx->displayvariables);CHKERRQ(ierr);
6759   ierr = PetscMalloc1(ctx->ndisplayvariables,&ctx->displayvalues);CHKERRQ(ierr);
6760   j = 0;
6761   while (displaynames[j]) {
6762     k = 0;
6763     while (ctx->names[k]) {
6764       PetscBool flg;
6765       ierr = PetscStrcmp(displaynames[j],ctx->names[k],&flg);CHKERRQ(ierr);
6766       if (flg) {
6767         ctx->displayvariables[j] = k;
6768         break;
6769       }
6770       k++;
6771     }
6772     j++;
6773   }
6774   PetscFunctionReturn(0);
6775 }
6776 
6777 
6778 #undef __FUNCT__
6779 #define __FUNCT__ "TSMonitorLGSetDisplayVariables"
6780 /*@C
6781    TSMonitorLGSetDisplayVariables - Sets the variables that are to be display in the monitor
6782 
6783    Collective on TS
6784 
6785    Input Parameters:
6786 +  ts - the TS context
6787 .  displaynames - the names of the components, final string must be NULL
6788 
6789    Notes: If the TS object does not have a TSMonitorLGCtx associated with it then this function is ignored
6790 
6791    Level: intermediate
6792 
6793 .keywords: TS,  vector, monitor, view
6794 
6795 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetVariableNames()
6796 @*/
6797 PetscErrorCode  TSMonitorLGSetDisplayVariables(TS ts,const char * const *displaynames)
6798 {
6799   PetscInt          i;
6800   PetscErrorCode    ierr;
6801 
6802   PetscFunctionBegin;
6803   for (i=0; i<ts->numbermonitors; i++) {
6804     if (ts->monitor[i] == TSMonitorLGSolution) {
6805       ierr = TSMonitorLGCtxSetDisplayVariables((TSMonitorLGCtx)ts->monitorcontext[i],displaynames);CHKERRQ(ierr);
6806       break;
6807     }
6808   }
6809   PetscFunctionReturn(0);
6810 }
6811 
6812 #undef __FUNCT__
6813 #define __FUNCT__ "TSMonitorLGSetTransform"
6814 /*@C
6815    TSMonitorLGSetTransform - Solution vector will be transformed by provided function before being displayed
6816 
6817    Collective on TS
6818 
6819    Input Parameters:
6820 +  ts - the TS context
6821 .  transform - the transform function
6822 .  destroy - function to destroy the optional context
6823 -  ctx - optional context used by transform function
6824 
6825    Notes: If the TS object does not have a TSMonitorLGCtx associated with it then this function is ignored
6826 
6827    Level: intermediate
6828 
6829 .keywords: TS,  vector, monitor, view
6830 
6831 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetVariableNames(), TSMonitorLGCtxSetTransform()
6832 @*/
6833 PetscErrorCode  TSMonitorLGSetTransform(TS ts,PetscErrorCode (*transform)(void*,Vec,Vec*),PetscErrorCode (*destroy)(void*),void *tctx)
6834 {
6835   PetscInt          i;
6836   PetscErrorCode    ierr;
6837 
6838   PetscFunctionBegin;
6839   for (i=0; i<ts->numbermonitors; i++) {
6840     if (ts->monitor[i] == TSMonitorLGSolution) {
6841       ierr = TSMonitorLGCtxSetTransform((TSMonitorLGCtx)ts->monitorcontext[i],transform,destroy,tctx);CHKERRQ(ierr);
6842     }
6843   }
6844   PetscFunctionReturn(0);
6845 }
6846 
6847 #undef __FUNCT__
6848 #define __FUNCT__ "TSMonitorLGCtxSetTransform"
6849 /*@C
6850    TSMonitorLGCtxSetTransform - Solution vector will be transformed by provided function before being displayed
6851 
6852    Collective on TSLGCtx
6853 
6854    Input Parameters:
6855 +  ts - the TS context
6856 .  transform - the transform function
6857 .  destroy - function to destroy the optional context
6858 -  ctx - optional context used by transform function
6859 
6860    Level: intermediate
6861 
6862 .keywords: TS,  vector, monitor, view
6863 
6864 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetVariableNames(), TSMonitorLGSetTransform()
6865 @*/
6866 PetscErrorCode  TSMonitorLGCtxSetTransform(TSMonitorLGCtx ctx,PetscErrorCode (*transform)(void*,Vec,Vec*),PetscErrorCode (*destroy)(void*),void *tctx)
6867 {
6868   PetscFunctionBegin;
6869   ctx->transform    = transform;
6870   ctx->transformdestroy = destroy;
6871   ctx->transformctx = tctx;
6872   PetscFunctionReturn(0);
6873 }
6874 
6875 #undef __FUNCT__
6876 #define __FUNCT__ "TSMonitorLGError"
6877 /*@C
6878    TSMonitorLGError - Monitors progress of the TS solvers by plotting each component of the solution vector
6879        in a time based line graph
6880 
6881    Collective on TS
6882 
6883    Input Parameters:
6884 +  ts - the TS context
6885 .  step - current time-step
6886 .  ptime - current time
6887 .  u - current solution
6888 -  dctx - TSMonitorLGCtx object created with TSMonitorLGCtxCreate()
6889 
6890    Level: intermediate
6891 
6892    Notes: Each process in a parallel run displays its component errors in a separate window
6893 
6894    The user must provide the solution using TSSetSolutionFunction() to use this monitor.
6895 
6896    Options Database Keys:
6897 .  -ts_monitor_lg_error - create a graphical monitor of error history
6898 
6899 .keywords: TS,  vector, monitor, view
6900 
6901 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSSetSolutionFunction()
6902 @*/
6903 PetscErrorCode  TSMonitorLGError(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
6904 {
6905   PetscErrorCode    ierr;
6906   TSMonitorLGCtx    ctx = (TSMonitorLGCtx)dummy;
6907   const PetscScalar *yy;
6908   Vec               y;
6909 
6910   PetscFunctionBegin;
6911   if (!step) {
6912     PetscDrawAxis axis;
6913     PetscInt      dim;
6914     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
6915     ierr = PetscDrawAxisSetLabels(axis,"Error in solution as function of time","Time","Solution");CHKERRQ(ierr);
6916     ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
6917     ierr = PetscDrawLGSetDimension(ctx->lg,dim);CHKERRQ(ierr);
6918     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
6919   }
6920   ierr = VecDuplicate(u,&y);CHKERRQ(ierr);
6921   ierr = TSComputeSolutionFunction(ts,ptime,y);CHKERRQ(ierr);
6922   ierr = VecAXPY(y,-1.0,u);CHKERRQ(ierr);
6923   ierr = VecGetArrayRead(y,&yy);CHKERRQ(ierr);
6924 #if defined(PETSC_USE_COMPLEX)
6925   {
6926     PetscReal *yreal;
6927     PetscInt  i,n;
6928     ierr = VecGetLocalSize(y,&n);CHKERRQ(ierr);
6929     ierr = PetscMalloc1(n,&yreal);CHKERRQ(ierr);
6930     for (i=0; i<n; i++) yreal[i] = PetscRealPart(yy[i]);
6931     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yreal);CHKERRQ(ierr);
6932     ierr = PetscFree(yreal);CHKERRQ(ierr);
6933   }
6934 #else
6935   ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yy);CHKERRQ(ierr);
6936 #endif
6937   ierr = VecRestoreArrayRead(y,&yy);CHKERRQ(ierr);
6938   ierr = VecDestroy(&y);CHKERRQ(ierr);
6939   if (((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason)) {
6940     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
6941     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
6942   }
6943   PetscFunctionReturn(0);
6944 }
6945 
6946 #undef __FUNCT__
6947 #define __FUNCT__ "TSMonitorLGSNESIterations"
6948 PetscErrorCode TSMonitorLGSNESIterations(TS ts,PetscInt n,PetscReal ptime,Vec v,void *monctx)
6949 {
6950   TSMonitorLGCtx ctx = (TSMonitorLGCtx) monctx;
6951   PetscReal      x   = ptime,y;
6952   PetscErrorCode ierr;
6953   PetscInt       its;
6954 
6955   PetscFunctionBegin;
6956   if (n < 0) PetscFunctionReturn(0); /* -1 indicates interpolated solution */
6957   if (!n) {
6958     PetscDrawAxis axis;
6959     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
6960     ierr = PetscDrawAxisSetLabels(axis,"Nonlinear iterations as function of time","Time","SNES Iterations");CHKERRQ(ierr);
6961     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
6962     ctx->snes_its = 0;
6963   }
6964   ierr = TSGetSNESIterations(ts,&its);CHKERRQ(ierr);
6965   y    = its - ctx->snes_its;
6966   ierr = PetscDrawLGAddPoint(ctx->lg,&x,&y);CHKERRQ(ierr);
6967   if (((ctx->howoften > 0) && (!(n % ctx->howoften)) && (n > -1)) || ((ctx->howoften == -1) && (n == -1))) {
6968     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
6969     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
6970   }
6971   ctx->snes_its = its;
6972   PetscFunctionReturn(0);
6973 }
6974 
6975 #undef __FUNCT__
6976 #define __FUNCT__ "TSMonitorLGKSPIterations"
6977 PetscErrorCode TSMonitorLGKSPIterations(TS ts,PetscInt n,PetscReal ptime,Vec v,void *monctx)
6978 {
6979   TSMonitorLGCtx ctx = (TSMonitorLGCtx) monctx;
6980   PetscReal      x   = ptime,y;
6981   PetscErrorCode ierr;
6982   PetscInt       its;
6983 
6984   PetscFunctionBegin;
6985   if (n < 0) PetscFunctionReturn(0); /* -1 indicates interpolated solution */
6986   if (!n) {
6987     PetscDrawAxis axis;
6988     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
6989     ierr = PetscDrawAxisSetLabels(axis,"Linear iterations as function of time","Time","KSP Iterations");CHKERRQ(ierr);
6990     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
6991     ctx->ksp_its = 0;
6992   }
6993   ierr = TSGetKSPIterations(ts,&its);CHKERRQ(ierr);
6994   y    = its - ctx->ksp_its;
6995   ierr = PetscDrawLGAddPoint(ctx->lg,&x,&y);CHKERRQ(ierr);
6996   if (((ctx->howoften > 0) && (!(n % ctx->howoften)) && (n > -1)) || ((ctx->howoften == -1) && (n == -1))) {
6997     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
6998     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
6999   }
7000   ctx->ksp_its = its;
7001   PetscFunctionReturn(0);
7002 }
7003 
7004 #undef __FUNCT__
7005 #define __FUNCT__ "TSComputeLinearStability"
7006 /*@
7007    TSComputeLinearStability - computes the linear stability function at a point
7008 
7009    Collective on TS and Vec
7010 
7011    Input Parameters:
7012 +  ts - the TS context
7013 -  xr,xi - real and imaginary part of input arguments
7014 
7015    Output Parameters:
7016 .  yr,yi - real and imaginary part of function value
7017 
7018    Level: developer
7019 
7020 .keywords: TS, compute
7021 
7022 .seealso: TSSetRHSFunction(), TSComputeIFunction()
7023 @*/
7024 PetscErrorCode TSComputeLinearStability(TS ts,PetscReal xr,PetscReal xi,PetscReal *yr,PetscReal *yi)
7025 {
7026   PetscErrorCode ierr;
7027 
7028   PetscFunctionBegin;
7029   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
7030   if (!ts->ops->linearstability) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Linearized stability function not provided for this method");
7031   ierr = (*ts->ops->linearstability)(ts,xr,xi,yr,yi);CHKERRQ(ierr);
7032   PetscFunctionReturn(0);
7033 }
7034 
7035 /* ------------------------------------------------------------------------*/
7036 #undef __FUNCT__
7037 #define __FUNCT__ "TSMonitorEnvelopeCtxCreate"
7038 /*@C
7039    TSMonitorEnvelopeCtxCreate - Creates a context for use with TSMonitorEnvelope()
7040 
7041    Collective on TS
7042 
7043    Input Parameters:
7044 .  ts  - the ODE solver object
7045 
7046    Output Parameter:
7047 .  ctx - the context
7048 
7049    Level: intermediate
7050 
7051 .keywords: TS, monitor, line graph, residual, seealso
7052 
7053 .seealso: TSMonitorLGTimeStep(), TSMonitorSet(), TSMonitorLGSolution(), TSMonitorLGError()
7054 
7055 @*/
7056 PetscErrorCode  TSMonitorEnvelopeCtxCreate(TS ts,TSMonitorEnvelopeCtx *ctx)
7057 {
7058   PetscErrorCode ierr;
7059 
7060   PetscFunctionBegin;
7061   ierr = PetscNew(ctx);CHKERRQ(ierr);
7062   PetscFunctionReturn(0);
7063 }
7064 
7065 #undef __FUNCT__
7066 #define __FUNCT__ "TSMonitorEnvelope"
7067 /*@C
7068    TSMonitorEnvelope - Monitors the maximum and minimum value of each component of the solution
7069 
7070    Collective on TS
7071 
7072    Input Parameters:
7073 +  ts - the TS context
7074 .  step - current time-step
7075 .  ptime - current time
7076 .  u  - current solution
7077 -  dctx - the envelope context
7078 
7079    Options Database:
7080 .  -ts_monitor_envelope
7081 
7082    Level: intermediate
7083 
7084    Notes: after a solve you can use TSMonitorEnvelopeGetBounds() to access the envelope
7085 
7086 .keywords: TS,  vector, monitor, view
7087 
7088 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorEnvelopeGetBounds(), TSMonitorEnvelopeCtxCreate()
7089 @*/
7090 PetscErrorCode  TSMonitorEnvelope(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dctx)
7091 {
7092   PetscErrorCode       ierr;
7093   TSMonitorEnvelopeCtx ctx = (TSMonitorEnvelopeCtx)dctx;
7094 
7095   PetscFunctionBegin;
7096   if (!ctx->max) {
7097     ierr = VecDuplicate(u,&ctx->max);CHKERRQ(ierr);
7098     ierr = VecDuplicate(u,&ctx->min);CHKERRQ(ierr);
7099     ierr = VecCopy(u,ctx->max);CHKERRQ(ierr);
7100     ierr = VecCopy(u,ctx->min);CHKERRQ(ierr);
7101   } else {
7102     ierr = VecPointwiseMax(ctx->max,u,ctx->max);CHKERRQ(ierr);
7103     ierr = VecPointwiseMin(ctx->min,u,ctx->min);CHKERRQ(ierr);
7104   }
7105   PetscFunctionReturn(0);
7106 }
7107 
7108 
7109 #undef __FUNCT__
7110 #define __FUNCT__ "TSMonitorEnvelopeGetBounds"
7111 /*@C
7112    TSMonitorEnvelopeGetBounds - Gets the bounds for the components of the solution
7113 
7114    Collective on TS
7115 
7116    Input Parameter:
7117 .  ts - the TS context
7118 
7119    Output Parameter:
7120 +  max - the maximum values
7121 -  min - the minimum values
7122 
7123    Notes: If the TS does not have a TSMonitorEnvelopeCtx associated with it then this function is ignored
7124 
7125    Level: intermediate
7126 
7127 .keywords: TS,  vector, monitor, view
7128 
7129 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetDisplayVariables()
7130 @*/
7131 PetscErrorCode  TSMonitorEnvelopeGetBounds(TS ts,Vec *max,Vec *min)
7132 {
7133   PetscInt i;
7134 
7135   PetscFunctionBegin;
7136   if (max) *max = NULL;
7137   if (min) *min = NULL;
7138   for (i=0; i<ts->numbermonitors; i++) {
7139     if (ts->monitor[i] == TSMonitorEnvelope) {
7140       TSMonitorEnvelopeCtx  ctx = (TSMonitorEnvelopeCtx) ts->monitorcontext[i];
7141       if (max) *max = ctx->max;
7142       if (min) *min = ctx->min;
7143       break;
7144     }
7145   }
7146   PetscFunctionReturn(0);
7147 }
7148 
7149 #undef __FUNCT__
7150 #define __FUNCT__ "TSMonitorEnvelopeCtxDestroy"
7151 /*@C
7152    TSMonitorEnvelopeCtxDestroy - Destroys a context that was created  with TSMonitorEnvelopeCtxCreate().
7153 
7154    Collective on TSMonitorEnvelopeCtx
7155 
7156    Input Parameter:
7157 .  ctx - the monitor context
7158 
7159    Level: intermediate
7160 
7161 .keywords: TS, monitor, line graph, destroy
7162 
7163 .seealso: TSMonitorLGCtxCreate(),  TSMonitorSet(), TSMonitorLGTimeStep()
7164 @*/
7165 PetscErrorCode  TSMonitorEnvelopeCtxDestroy(TSMonitorEnvelopeCtx *ctx)
7166 {
7167   PetscErrorCode ierr;
7168 
7169   PetscFunctionBegin;
7170   ierr = VecDestroy(&(*ctx)->min);CHKERRQ(ierr);
7171   ierr = VecDestroy(&(*ctx)->max);CHKERRQ(ierr);
7172   ierr = PetscFree(*ctx);CHKERRQ(ierr);
7173   PetscFunctionReturn(0);
7174 }
7175 
7176 #undef __FUNCT__
7177 #define __FUNCT__ "TSRollBack"
7178 /*@
7179    TSRollBack - Rolls back one time step
7180 
7181    Collective on TS
7182 
7183    Input Parameter:
7184 .  ts - the TS context obtained from TSCreate()
7185 
7186    Level: advanced
7187 
7188 .keywords: TS, timestep, rollback
7189 
7190 .seealso: TSCreate(), TSSetUp(), TSDestroy(), TSSolve(), TSSetPreStep(), TSSetPreStage(), TSInterpolate()
7191 @*/
7192 PetscErrorCode  TSRollBack(TS ts)
7193 {
7194   PetscErrorCode ierr;
7195 
7196   PetscFunctionBegin;
7197   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
7198   if (ts->steprollback) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONGSTATE,"TSRollBack already called");
7199   if (!ts->ops->rollback) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSRollBack not implemented for type '%s'",((PetscObject)ts)->type_name);
7200   ierr = (*ts->ops->rollback)(ts);CHKERRQ(ierr);
7201   ts->time_step = ts->ptime - ts->ptime_prev;
7202   ts->ptime = ts->ptime_prev;
7203   ts->ptime_prev = ts->ptime_prev_rollback;
7204   ts->steps--; ts->total_steps--;
7205   ts->steprollback = PETSC_TRUE;
7206   PetscFunctionReturn(0);
7207 }
7208 
7209 #undef __FUNCT__
7210 #define __FUNCT__ "TSGetStages"
7211 /*@
7212    TSGetStages - Get the number of stages and stage values
7213 
7214    Input Parameter:
7215 .  ts - the TS context obtained from TSCreate()
7216 
7217    Level: advanced
7218 
7219 .keywords: TS, getstages
7220 
7221 .seealso: TSCreate()
7222 @*/
7223 PetscErrorCode  TSGetStages(TS ts,PetscInt *ns,Vec **Y)
7224 {
7225   PetscErrorCode ierr;
7226 
7227   PetscFunctionBegin;
7228   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
7229   PetscValidPointer(ns,2);
7230 
7231   if (!ts->ops->getstages) *ns=0;
7232   else {
7233     ierr = (*ts->ops->getstages)(ts,ns,Y);CHKERRQ(ierr);
7234   }
7235   PetscFunctionReturn(0);
7236 }
7237 
7238 #undef __FUNCT__
7239 #define __FUNCT__ "TSComputeIJacobianDefaultColor"
7240 /*@C
7241   TSComputeIJacobianDefaultColor - Computes the Jacobian using finite differences and coloring to exploit matrix sparsity.
7242 
7243   Collective on SNES
7244 
7245   Input Parameters:
7246 + ts - the TS context
7247 . t - current timestep
7248 . U - state vector
7249 . Udot - time derivative of state vector
7250 . shift - shift to apply, see note below
7251 - ctx - an optional user context
7252 
7253   Output Parameters:
7254 + J - Jacobian matrix (not altered in this routine)
7255 - B - newly computed Jacobian matrix to use with preconditioner (generally the same as J)
7256 
7257   Level: intermediate
7258 
7259   Notes:
7260   If F(t,U,Udot)=0 is the DAE, the required Jacobian is
7261 
7262   dF/dU + shift*dF/dUdot
7263 
7264   Most users should not need to explicitly call this routine, as it
7265   is used internally within the nonlinear solvers.
7266 
7267   This will first try to get the coloring from the DM.  If the DM type has no coloring
7268   routine, then it will try to get the coloring from the matrix.  This requires that the
7269   matrix have nonzero entries precomputed.
7270 
7271 .keywords: TS, finite differences, Jacobian, coloring, sparse
7272 .seealso: TSSetIJacobian(), MatFDColoringCreate(), MatFDColoringSetFunction()
7273 @*/
7274 PetscErrorCode TSComputeIJacobianDefaultColor(TS ts,PetscReal t,Vec U,Vec Udot,PetscReal shift,Mat J,Mat B,void *ctx)
7275 {
7276   SNES           snes;
7277   MatFDColoring  color;
7278   PetscBool      hascolor, matcolor = PETSC_FALSE;
7279   PetscErrorCode ierr;
7280 
7281   PetscFunctionBegin;
7282   ierr = PetscOptionsGetBool(((PetscObject)ts)->options,((PetscObject) ts)->prefix, "-ts_fd_color_use_mat", &matcolor, NULL);CHKERRQ(ierr);
7283   ierr = PetscObjectQuery((PetscObject) B, "TSMatFDColoring", (PetscObject *) &color);CHKERRQ(ierr);
7284   if (!color) {
7285     DM         dm;
7286     ISColoring iscoloring;
7287 
7288     ierr = TSGetDM(ts, &dm);CHKERRQ(ierr);
7289     ierr = DMHasColoring(dm, &hascolor);CHKERRQ(ierr);
7290     if (hascolor && !matcolor) {
7291       ierr = DMCreateColoring(dm, IS_COLORING_GLOBAL, &iscoloring);CHKERRQ(ierr);
7292       ierr = MatFDColoringCreate(B, iscoloring, &color);CHKERRQ(ierr);
7293       ierr = MatFDColoringSetFunction(color, (PetscErrorCode (*)(void)) SNESTSFormFunction, (void *) ts);CHKERRQ(ierr);
7294       ierr = MatFDColoringSetFromOptions(color);CHKERRQ(ierr);
7295       ierr = MatFDColoringSetUp(B, iscoloring, color);CHKERRQ(ierr);
7296       ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
7297     } else {
7298       MatColoring mc;
7299 
7300       ierr = MatColoringCreate(B, &mc);CHKERRQ(ierr);
7301       ierr = MatColoringSetDistance(mc, 2);CHKERRQ(ierr);
7302       ierr = MatColoringSetType(mc, MATCOLORINGSL);CHKERRQ(ierr);
7303       ierr = MatColoringSetFromOptions(mc);CHKERRQ(ierr);
7304       ierr = MatColoringApply(mc, &iscoloring);CHKERRQ(ierr);
7305       ierr = MatColoringDestroy(&mc);CHKERRQ(ierr);
7306       ierr = MatFDColoringCreate(B, iscoloring, &color);CHKERRQ(ierr);
7307       ierr = MatFDColoringSetFunction(color, (PetscErrorCode (*)(void)) SNESTSFormFunction, (void *) ts);CHKERRQ(ierr);
7308       ierr = MatFDColoringSetFromOptions(color);CHKERRQ(ierr);
7309       ierr = MatFDColoringSetUp(B, iscoloring, color);CHKERRQ(ierr);
7310       ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
7311     }
7312     ierr = PetscObjectCompose((PetscObject) B, "TSMatFDColoring", (PetscObject) color);CHKERRQ(ierr);
7313     ierr = PetscObjectDereference((PetscObject) color);CHKERRQ(ierr);
7314   }
7315   ierr = TSGetSNES(ts, &snes);CHKERRQ(ierr);
7316   ierr = MatFDColoringApply(B, color, U, snes);CHKERRQ(ierr);
7317   if (J != B) {
7318     ierr = MatAssemblyBegin(J, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
7319     ierr = MatAssemblyEnd(J, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
7320   }
7321   PetscFunctionReturn(0);
7322 }
7323 
7324 #undef __FUNCT__
7325 #define __FUNCT__ "TSSetFunctionDomainError"
7326 /*@
7327     TSSetFunctionDomainError - Set the function testing if the current state vector is valid
7328 
7329     Input Parameters:
7330     ts - the TS context
7331     func - function called within TSFunctionDomainError
7332 
7333     Level: intermediate
7334 
7335 .keywords: TS, state, domain
7336 .seealso: TSAdaptCheckStage(), TSFunctionDomainError()
7337 @*/
7338 
7339 PetscErrorCode TSSetFunctionDomainError(TS ts, PetscErrorCode (*func)(TS,PetscReal,Vec,PetscBool*))
7340 {
7341   PetscFunctionBegin;
7342   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
7343   ts->functiondomainerror = func;
7344   PetscFunctionReturn(0);
7345 }
7346 
7347 #undef __FUNCT__
7348 #define __FUNCT__ "TSFunctionDomainError"
7349 /*@
7350     TSFunctionDomainError - Check if the current state is valid
7351 
7352     Input Parameters:
7353     ts - the TS context
7354     stagetime - time of the simulation
7355     Y - state vector to check.
7356 
7357     Output Parameter:
7358     accept - Set to PETSC_FALSE if the current state vector is valid.
7359 
7360     Note:
7361     This function should be used to ensure the state is in a valid part of the space.
7362     For example, one can ensure here all values are positive.
7363 
7364     Level: advanced
7365 @*/
7366 PetscErrorCode TSFunctionDomainError(TS ts,PetscReal stagetime,Vec Y,PetscBool* accept)
7367 {
7368   PetscErrorCode ierr;
7369 
7370   PetscFunctionBegin;
7371 
7372   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
7373   *accept = PETSC_TRUE;
7374   if (ts->functiondomainerror) {
7375     PetscStackCallStandard((*ts->functiondomainerror),(ts,stagetime,Y,accept));
7376   }
7377   PetscFunctionReturn(0);
7378 }
7379 
7380 #undef  __FUNCT__
7381 #define __FUNCT__ "TSClone"
7382 /*@C
7383   TSClone - This function clones a time step object.
7384 
7385   Collective on MPI_Comm
7386 
7387   Input Parameter:
7388 . tsin    - The input TS
7389 
7390   Output Parameter:
7391 . tsout   - The output TS (cloned)
7392 
7393   Notes:
7394   This function is used to create a clone of a TS object. It is used in ARKIMEX for initializing the slope for first stage explicit methods. It will likely be replaced in the future with a mechanism of switching methods on the fly.
7395 
7396   When using TSDestroy() on a clone the user has to first reset the correct TS reference in the embedded SNES object: e.g.: by running SNES snes_dup=NULL; TSGetSNES(ts,&snes_dup); ierr = TSSetSNES(ts,snes_dup);
7397 
7398   Level: developer
7399 
7400 .keywords: TS, clone
7401 .seealso: TSCreate(), TSSetType(), TSSetUp(), TSDestroy(), TSSetProblemType()
7402 @*/
7403 PetscErrorCode  TSClone(TS tsin, TS *tsout)
7404 {
7405   TS             t;
7406   PetscErrorCode ierr;
7407   SNES           snes_start;
7408   DM             dm;
7409   TSType         type;
7410 
7411   PetscFunctionBegin;
7412   PetscValidPointer(tsin,1);
7413   *tsout = NULL;
7414 
7415   ierr = PetscHeaderCreate(t, TS_CLASSID, "TS", "Time stepping", "TS", PetscObjectComm((PetscObject)tsin), TSDestroy, TSView);CHKERRQ(ierr);
7416 
7417   /* General TS description */
7418   t->numbermonitors    = 0;
7419   t->setupcalled       = 0;
7420   t->ksp_its           = 0;
7421   t->snes_its          = 0;
7422   t->nwork             = 0;
7423   t->rhsjacobian.time  = -1e20;
7424   t->rhsjacobian.scale = 1.;
7425   t->ijacobian.shift   = 1.;
7426 
7427   ierr = TSGetSNES(tsin,&snes_start);CHKERRQ(ierr);
7428   ierr = TSSetSNES(t,snes_start);CHKERRQ(ierr);
7429 
7430   ierr = TSGetDM(tsin,&dm);CHKERRQ(ierr);
7431   ierr = TSSetDM(t,dm);CHKERRQ(ierr);
7432 
7433   t->adapt = tsin->adapt;
7434   ierr = PetscObjectReference((PetscObject)t->adapt);CHKERRQ(ierr);
7435 
7436   t->problem_type      = tsin->problem_type;
7437   t->ptime             = tsin->ptime;
7438   t->time_step         = tsin->time_step;
7439   t->max_time          = tsin->max_time;
7440   t->steps             = tsin->steps;
7441   t->max_steps         = tsin->max_steps;
7442   t->equation_type     = tsin->equation_type;
7443   t->atol              = tsin->atol;
7444   t->rtol              = tsin->rtol;
7445   t->max_snes_failures = tsin->max_snes_failures;
7446   t->max_reject        = tsin->max_reject;
7447   t->errorifstepfailed = tsin->errorifstepfailed;
7448 
7449   ierr = TSGetType(tsin,&type);CHKERRQ(ierr);
7450   ierr = TSSetType(t,type);CHKERRQ(ierr);
7451 
7452   t->vec_sol           = NULL;
7453 
7454   t->cfltime          = tsin->cfltime;
7455   t->cfltime_local    = tsin->cfltime_local;
7456   t->exact_final_time = tsin->exact_final_time;
7457 
7458   ierr = PetscMemcpy(t->ops,tsin->ops,sizeof(struct _TSOps));CHKERRQ(ierr);
7459 
7460   if (((PetscObject)tsin)->fortran_func_pointers) {
7461     PetscInt i;
7462     ierr = PetscMalloc((10)*sizeof(void(*)(void)),&((PetscObject)t)->fortran_func_pointers);CHKERRQ(ierr);
7463     for (i=0; i<10; i++) {
7464       ((PetscObject)t)->fortran_func_pointers[i] = ((PetscObject)tsin)->fortran_func_pointers[i];
7465     }
7466   }
7467   *tsout = t;
7468   PetscFunctionReturn(0);
7469 }
7470