xref: /petsc/src/ts/interface/ts.c (revision e5afcf2835ad2df3c79a70d4d9a0fbb86e97247e)
1 #include <petsc/private/tsimpl.h>        /*I "petscts.h"  I*/
2 #include <petscdmshell.h>
3 #include <petscdmda.h>
4 #include <petscviewer.h>
5 #include <petscdraw.h>
6 
7 /* Logging support */
8 PetscClassId  TS_CLASSID, DMTS_CLASSID;
9 PetscLogEvent TS_Step, TS_PseudoComputeTimeStep, TS_FunctionEval, TS_JacobianEval;
10 
11 const char *const TSExactFinalTimeOptions[] = {"UNSPECIFIED","STEPOVER","INTERPOLATE","MATCHSTEP","TSExactFinalTimeOption","TS_EXACTFINALTIME_",0};
12 
13 /*@C
14    TSMonitorSetFromOptions - Sets a monitor function and viewer appropriate for the type indicated by the user
15 
16    Collective on TS
17 
18    Input Parameters:
19 +  ts - TS object you wish to monitor
20 .  name - the monitor type one is seeking
21 .  help - message indicating what monitoring is done
22 .  manual - manual page for the monitor
23 .  monitor - the monitor function
24 -  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
25 
26    Level: developer
27 
28 .seealso: PetscOptionsGetViewer(), PetscOptionsGetReal(), PetscOptionsHasName(), PetscOptionsGetString(),
29           PetscOptionsGetIntArray(), PetscOptionsGetRealArray(), PetscOptionsBool()
30           PetscOptionsInt(), PetscOptionsString(), PetscOptionsReal(), PetscOptionsBool(),
31           PetscOptionsName(), PetscOptionsBegin(), PetscOptionsEnd(), PetscOptionsHead(),
32           PetscOptionsStringArray(),PetscOptionsRealArray(), PetscOptionsScalar(),
33           PetscOptionsBoolGroupBegin(), PetscOptionsBoolGroup(), PetscOptionsBoolGroupEnd(),
34           PetscOptionsFList(), PetscOptionsEList()
35 @*/
36 PetscErrorCode  TSMonitorSetFromOptions(TS ts,const char name[],const char help[], const char manual[],PetscErrorCode (*monitor)(TS,PetscInt,PetscReal,Vec,PetscViewerAndFormat*),PetscErrorCode (*monitorsetup)(TS,PetscViewerAndFormat*))
37 {
38   PetscErrorCode    ierr;
39   PetscViewer       viewer;
40   PetscViewerFormat format;
41   PetscBool         flg;
42 
43   PetscFunctionBegin;
44   ierr = PetscOptionsGetViewer(PetscObjectComm((PetscObject)ts),((PetscObject) ts)->options,((PetscObject)ts)->prefix,name,&viewer,&format,&flg);CHKERRQ(ierr);
45   if (flg) {
46     PetscViewerAndFormat *vf;
47     ierr = PetscViewerAndFormatCreate(viewer,format,&vf);CHKERRQ(ierr);
48     ierr = PetscObjectDereference((PetscObject)viewer);CHKERRQ(ierr);
49     if (monitorsetup) {
50       ierr = (*monitorsetup)(ts,vf);CHKERRQ(ierr);
51     }
52     ierr = TSMonitorSet(ts,(PetscErrorCode (*)(TS,PetscInt,PetscReal,Vec,void*))monitor,vf,(PetscErrorCode (*)(void**))PetscViewerAndFormatDestroy);CHKERRQ(ierr);
53   }
54   PetscFunctionReturn(0);
55 }
56 
57 static PetscErrorCode TSAdaptSetDefaultType(TSAdapt adapt,TSAdaptType default_type)
58 {
59   PetscErrorCode ierr;
60 
61   PetscFunctionBegin;
62   PetscValidHeaderSpecific(adapt,TSADAPT_CLASSID,1);
63   PetscValidCharPointer(default_type,2);
64   if (!((PetscObject)adapt)->type_name) {
65     ierr = TSAdaptSetType(adapt,default_type);CHKERRQ(ierr);
66   }
67   PetscFunctionReturn(0);
68 }
69 
70 /*@
71    TSSetFromOptions - Sets various TS parameters from user options.
72 
73    Collective on TS
74 
75    Input Parameter:
76 .  ts - the TS context obtained from TSCreate()
77 
78    Options Database Keys:
79 +  -ts_type <type> - TSEULER, TSBEULER, TSSUNDIALS, TSPSEUDO, TSCN, TSRK, TSTHETA, TSALPHA, TSGLLE, TSSSP, TSGLEE, TSBSYMP
80 .  -ts_save_trajectory - checkpoint the solution at each time-step
81 .  -ts_max_time <time> - maximum time to compute to
82 .  -ts_max_steps <steps> - maximum number of time-steps to take
83 .  -ts_init_time <time> - initial time to start computation
84 .  -ts_final_time <time> - final time to compute to (deprecated: use -ts_max_time)
85 .  -ts_dt <dt> - initial time step
86 .  -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
87 .  -ts_max_snes_failures <maxfailures> - Maximum number of nonlinear solve failures allowed
88 .  -ts_max_reject <maxrejects> - Maximum number of step rejections before step fails
89 .  -ts_error_if_step_fails <true,false> - Error if no step succeeds
90 .  -ts_rtol <rtol> - relative tolerance for local truncation error
91 .  -ts_atol <atol> Absolute tolerance for local truncation error
92 .  -ts_rhs_jacobian_test_mult -mat_shell_test_mult_view - test the Jacobian at each iteration against finite difference with RHS function
93 .  -ts_rhs_jacobian_test_mult_transpose -mat_shell_test_mult_transpose_view - test the Jacobian at each iteration against finite difference with RHS function
94 .  -ts_adjoint_solve <yes,no> After solving the ODE/DAE solve the adjoint problem (requires -ts_save_trajectory)
95 .  -ts_fd_color - Use finite differences with coloring to compute IJacobian
96 .  -ts_monitor - print information at each timestep
97 .  -ts_monitor_lg_solution - Monitor solution graphically
98 .  -ts_monitor_lg_error - Monitor error graphically
99 .  -ts_monitor_error - Monitors norm of error
100 .  -ts_monitor_lg_timestep - Monitor timestep size graphically
101 .  -ts_monitor_lg_timestep_log - Monitor log timestep size graphically
102 .  -ts_monitor_lg_snes_iterations - Monitor number nonlinear iterations for each timestep graphically
103 .  -ts_monitor_lg_ksp_iterations - Monitor number nonlinear iterations for each timestep graphically
104 .  -ts_monitor_sp_eig - Monitor eigenvalues of linearized operator graphically
105 .  -ts_monitor_draw_solution - Monitor solution graphically
106 .  -ts_monitor_draw_solution_phase  <xleft,yleft,xright,yright> - Monitor solution graphically with phase diagram, requires problem with exactly 2 degrees of freedom
107 .  -ts_monitor_draw_error - Monitor error graphically, requires use to have provided TSSetSolutionFunction()
108 .  -ts_monitor_solution [ascii binary draw][:filename][:viewerformat] - monitors the solution at each timestep
109 .  -ts_monitor_solution_vtk <filename.vts,filename.vtu> - Save each time step to a binary file, use filename-%%03D.vts (filename-%%03D.vtu)
110 .  -ts_monitor_envelope - determine maximum and minimum value of each component of the solution over the solution time
111 
112    Developer Note: We should unify all the -ts_monitor options in the way that -xxx_view has been unified
113 
114    Level: beginner
115 
116 .keywords: TS, timestep, set, options, database
117 
118 .seealso: TSGetType()
119 @*/
120 PetscErrorCode  TSSetFromOptions(TS ts)
121 {
122   PetscBool              opt,flg,tflg;
123   PetscErrorCode         ierr;
124   char                   monfilename[PETSC_MAX_PATH_LEN];
125   PetscReal              time_step;
126   TSExactFinalTimeOption eftopt;
127   char                   dir[16];
128   TSIFunction            ifun;
129   const char             *defaultType;
130   char                   typeName[256];
131 
132   PetscFunctionBegin;
133   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
134 
135   ierr = TSRegisterAll();CHKERRQ(ierr);
136   ierr = TSGetIFunction(ts,NULL,&ifun,NULL);CHKERRQ(ierr);
137 
138   ierr = PetscObjectOptionsBegin((PetscObject)ts);CHKERRQ(ierr);
139   if (((PetscObject)ts)->type_name) defaultType = ((PetscObject)ts)->type_name;
140   else defaultType = ifun ? TSBEULER : TSEULER;
141   ierr = PetscOptionsFList("-ts_type","TS method","TSSetType",TSList,defaultType,typeName,256,&opt);CHKERRQ(ierr);
142   if (opt) {
143     ierr = TSSetType(ts,typeName);CHKERRQ(ierr);
144   } else {
145     ierr = TSSetType(ts,defaultType);CHKERRQ(ierr);
146   }
147 
148   /* Handle generic TS options */
149   ierr = PetscOptionsDeprecated("-ts_final_time","-ts_max_time","3.10",NULL);CHKERRQ(ierr);
150   ierr = PetscOptionsReal("-ts_max_time","Maximum time to run to","TSSetMaxTime",ts->max_time,&ts->max_time,NULL);CHKERRQ(ierr);
151   ierr = PetscOptionsInt("-ts_max_steps","Maximum number of time steps","TSSetMaxSteps",ts->max_steps,&ts->max_steps,NULL);CHKERRQ(ierr);
152   ierr = PetscOptionsReal("-ts_init_time","Initial time","TSSetTime",ts->ptime,&ts->ptime,NULL);CHKERRQ(ierr);
153   ierr = PetscOptionsReal("-ts_dt","Initial time step","TSSetTimeStep",ts->time_step,&time_step,&flg);CHKERRQ(ierr);
154   if (flg) {ierr = TSSetTimeStep(ts,time_step);CHKERRQ(ierr);}
155   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);
156   if (flg) {ierr = TSSetExactFinalTime(ts,eftopt);CHKERRQ(ierr);}
157   ierr = PetscOptionsInt("-ts_max_snes_failures","Maximum number of nonlinear solve failures","TSSetMaxSNESFailures",ts->max_snes_failures,&ts->max_snes_failures,NULL);CHKERRQ(ierr);
158   ierr = PetscOptionsInt("-ts_max_reject","Maximum number of step rejections before step fails","TSSetMaxStepRejections",ts->max_reject,&ts->max_reject,NULL);CHKERRQ(ierr);
159   ierr = PetscOptionsBool("-ts_error_if_step_fails","Error if no step succeeds","TSSetErrorIfStepFails",ts->errorifstepfailed,&ts->errorifstepfailed,NULL);CHKERRQ(ierr);
160   ierr = PetscOptionsReal("-ts_rtol","Relative tolerance for local truncation error","TSSetTolerances",ts->rtol,&ts->rtol,NULL);CHKERRQ(ierr);
161   ierr = PetscOptionsReal("-ts_atol","Absolute tolerance for local truncation error","TSSetTolerances",ts->atol,&ts->atol,NULL);CHKERRQ(ierr);
162 
163   ierr = PetscOptionsBool("-ts_rhs_jacobian_test_mult","Test the RHS Jacobian for consistency with RHS at each solve ","None",ts->testjacobian,&ts->testjacobian,NULL);CHKERRQ(ierr);
164   ierr = PetscOptionsBool("-ts_rhs_jacobian_test_mult_transpose","Test the RHS Jacobian transpose for consistency with RHS at each solve ","None",ts->testjacobiantranspose,&ts->testjacobiantranspose,NULL);CHKERRQ(ierr);
165   ierr = PetscOptionsBool("-ts_use_splitrhsfunction","Use the split RHS function for multirate solvers ","TSSetUseSplitRHSFunction",ts->use_splitrhsfunction,&ts->use_splitrhsfunction,NULL);CHKERRQ(ierr);
166 #if defined(PETSC_HAVE_SAWS)
167   {
168   PetscBool set;
169   flg  = PETSC_FALSE;
170   ierr = PetscOptionsBool("-ts_saws_block","Block for SAWs memory snooper at end of TSSolve","PetscObjectSAWsBlock",((PetscObject)ts)->amspublishblock,&flg,&set);CHKERRQ(ierr);
171   if (set) {
172     ierr = PetscObjectSAWsSetBlock((PetscObject)ts,flg);CHKERRQ(ierr);
173   }
174   }
175 #endif
176 
177   /* Monitor options */
178   ierr = TSMonitorSetFromOptions(ts,"-ts_monitor","Monitor time and timestep size","TSMonitorDefault",TSMonitorDefault,NULL);CHKERRQ(ierr);
179   ierr = TSMonitorSetFromOptions(ts,"-ts_monitor_extreme","Monitor extreme values of the solution","TSMonitorExtreme",TSMonitorExtreme,NULL);CHKERRQ(ierr);
180   ierr = TSMonitorSetFromOptions(ts,"-ts_monitor_solution","View the solution at each timestep","TSMonitorSolution",TSMonitorSolution,NULL);CHKERRQ(ierr);
181 
182   ierr = PetscOptionsString("-ts_monitor_python","Use Python function","TSMonitorSet",0,monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
183   if (flg) {ierr = PetscPythonMonitorSet((PetscObject)ts,monfilename);CHKERRQ(ierr);}
184 
185   ierr = PetscOptionsName("-ts_monitor_lg_solution","Monitor solution graphically","TSMonitorLGSolution",&opt);CHKERRQ(ierr);
186   if (opt) {
187     TSMonitorLGCtx ctx;
188     PetscInt       howoften = 1;
189 
190     ierr = PetscOptionsInt("-ts_monitor_lg_solution","Monitor solution graphically","TSMonitorLGSolution",howoften,&howoften,NULL);CHKERRQ(ierr);
191     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
192     ierr = TSMonitorSet(ts,TSMonitorLGSolution,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
193   }
194 
195   ierr = PetscOptionsName("-ts_monitor_lg_error","Monitor error graphically","TSMonitorLGError",&opt);CHKERRQ(ierr);
196   if (opt) {
197     TSMonitorLGCtx ctx;
198     PetscInt       howoften = 1;
199 
200     ierr = PetscOptionsInt("-ts_monitor_lg_error","Monitor error graphically","TSMonitorLGError",howoften,&howoften,NULL);CHKERRQ(ierr);
201     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
202     ierr = TSMonitorSet(ts,TSMonitorLGError,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
203   }
204   ierr = TSMonitorSetFromOptions(ts,"-ts_monitor_error","View the error at each timestep","TSMonitorError",TSMonitorError,NULL);CHKERRQ(ierr);
205 
206   ierr = PetscOptionsName("-ts_monitor_lg_timestep","Monitor timestep size graphically","TSMonitorLGTimeStep",&opt);CHKERRQ(ierr);
207   if (opt) {
208     TSMonitorLGCtx ctx;
209     PetscInt       howoften = 1;
210 
211     ierr = PetscOptionsInt("-ts_monitor_lg_timestep","Monitor timestep size graphically","TSMonitorLGTimeStep",howoften,&howoften,NULL);CHKERRQ(ierr);
212     ierr = TSMonitorLGCtxCreate(PetscObjectComm((PetscObject)ts),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
213     ierr = TSMonitorSet(ts,TSMonitorLGTimeStep,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
214   }
215   ierr = PetscOptionsName("-ts_monitor_lg_timestep_log","Monitor log timestep size graphically","TSMonitorLGTimeStep",&opt);CHKERRQ(ierr);
216   if (opt) {
217     TSMonitorLGCtx ctx;
218     PetscInt       howoften = 1;
219 
220     ierr = PetscOptionsInt("-ts_monitor_lg_timestep_log","Monitor log timestep size graphically","TSMonitorLGTimeStep",howoften,&howoften,NULL);CHKERRQ(ierr);
221     ierr = TSMonitorLGCtxCreate(PetscObjectComm((PetscObject)ts),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
222     ierr = TSMonitorSet(ts,TSMonitorLGTimeStep,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
223     ctx->semilogy = PETSC_TRUE;
224   }
225 
226   ierr = PetscOptionsName("-ts_monitor_lg_snes_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGSNESIterations",&opt);CHKERRQ(ierr);
227   if (opt) {
228     TSMonitorLGCtx ctx;
229     PetscInt       howoften = 1;
230 
231     ierr = PetscOptionsInt("-ts_monitor_lg_snes_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGSNESIterations",howoften,&howoften,NULL);CHKERRQ(ierr);
232     ierr = TSMonitorLGCtxCreate(PetscObjectComm((PetscObject)ts),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
233     ierr = TSMonitorSet(ts,TSMonitorLGSNESIterations,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
234   }
235   ierr = PetscOptionsName("-ts_monitor_lg_ksp_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGKSPIterations",&opt);CHKERRQ(ierr);
236   if (opt) {
237     TSMonitorLGCtx ctx;
238     PetscInt       howoften = 1;
239 
240     ierr = PetscOptionsInt("-ts_monitor_lg_ksp_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGKSPIterations",howoften,&howoften,NULL);CHKERRQ(ierr);
241     ierr = TSMonitorLGCtxCreate(PetscObjectComm((PetscObject)ts),NULL,NULL,PETSC_DECIDE,PETSC_DECIDE,400,300,howoften,&ctx);CHKERRQ(ierr);
242     ierr = TSMonitorSet(ts,TSMonitorLGKSPIterations,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
243   }
244   ierr = PetscOptionsName("-ts_monitor_sp_eig","Monitor eigenvalues of linearized operator graphically","TSMonitorSPEig",&opt);CHKERRQ(ierr);
245   if (opt) {
246     TSMonitorSPEigCtx ctx;
247     PetscInt          howoften = 1;
248 
249     ierr = PetscOptionsInt("-ts_monitor_sp_eig","Monitor eigenvalues of linearized operator graphically","TSMonitorSPEig",howoften,&howoften,NULL);CHKERRQ(ierr);
250     ierr = TSMonitorSPEigCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
251     ierr = TSMonitorSet(ts,TSMonitorSPEig,ctx,(PetscErrorCode (*)(void**))TSMonitorSPEigCtxDestroy);CHKERRQ(ierr);
252   }
253   ierr = PetscOptionsName("-ts_monitor_sp_swarm","Display particle phase from the DMSwarm","TSMonitorSPSwarm",&opt);CHKERRQ(ierr);
254   if (opt) {
255     TSMonitorSPCtx  ctx;
256     PetscInt        howoften = 1;
257     ierr = PetscOptionsInt("-ts_monitor_sp_swarm","Display particles phase from the DMSwarm","TSMonitorSPSwarm",howoften,&howoften,NULL);CHKERRQ(ierr);
258     ierr = TSMonitorSPCtxCreate(PETSC_COMM_SELF, NULL, NULL, PETSC_DECIDE, PETSC_DECIDE, 300, 300, howoften, &ctx);CHKERRQ(ierr);
259     ierr = TSMonitorSet(ts, TSMonitorSPSwarmSolution, ctx, (PetscErrorCode (*)(void**))TSMonitorSPCtxDestroy);CHKERRQ(ierr);
260   }
261   opt  = PETSC_FALSE;
262   ierr = PetscOptionsName("-ts_monitor_draw_solution","Monitor solution graphically","TSMonitorDrawSolution",&opt);CHKERRQ(ierr);
263   if (opt) {
264     TSMonitorDrawCtx ctx;
265     PetscInt         howoften = 1;
266 
267     ierr = PetscOptionsInt("-ts_monitor_draw_solution","Monitor solution graphically","TSMonitorDrawSolution",howoften,&howoften,NULL);CHKERRQ(ierr);
268     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,"Computed Solution",PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
269     ierr = TSMonitorSet(ts,TSMonitorDrawSolution,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
270   }
271   opt  = PETSC_FALSE;
272   ierr = PetscOptionsName("-ts_monitor_draw_solution_phase","Monitor solution graphically","TSMonitorDrawSolutionPhase",&opt);CHKERRQ(ierr);
273   if (opt) {
274     TSMonitorDrawCtx ctx;
275     PetscReal        bounds[4];
276     PetscInt         n = 4;
277     PetscDraw        draw;
278     PetscDrawAxis    axis;
279 
280     ierr = PetscOptionsRealArray("-ts_monitor_draw_solution_phase","Monitor solution graphically","TSMonitorDrawSolutionPhase",bounds,&n,NULL);CHKERRQ(ierr);
281     if (n != 4) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Must provide bounding box of phase field");
282     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,1,&ctx);CHKERRQ(ierr);
283     ierr = PetscViewerDrawGetDraw(ctx->viewer,0,&draw);CHKERRQ(ierr);
284     ierr = PetscViewerDrawGetDrawAxis(ctx->viewer,0,&axis);CHKERRQ(ierr);
285     ierr = PetscDrawAxisSetLimits(axis,bounds[0],bounds[2],bounds[1],bounds[3]);CHKERRQ(ierr);
286     ierr = PetscDrawAxisSetLabels(axis,"Phase Diagram","Variable 1","Variable 2");CHKERRQ(ierr);
287     ierr = TSMonitorSet(ts,TSMonitorDrawSolutionPhase,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
288   }
289   opt  = PETSC_FALSE;
290   ierr = PetscOptionsName("-ts_monitor_draw_error","Monitor error graphically","TSMonitorDrawError",&opt);CHKERRQ(ierr);
291   if (opt) {
292     TSMonitorDrawCtx ctx;
293     PetscInt         howoften = 1;
294 
295     ierr = PetscOptionsInt("-ts_monitor_draw_error","Monitor error graphically","TSMonitorDrawError",howoften,&howoften,NULL);CHKERRQ(ierr);
296     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,"Error",PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
297     ierr = TSMonitorSet(ts,TSMonitorDrawError,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
298   }
299   opt  = PETSC_FALSE;
300   ierr = PetscOptionsName("-ts_monitor_draw_solution_function","Monitor solution provided by TSMonitorSetSolutionFunction() graphically","TSMonitorDrawSolutionFunction",&opt);CHKERRQ(ierr);
301   if (opt) {
302     TSMonitorDrawCtx ctx;
303     PetscInt         howoften = 1;
304 
305     ierr = PetscOptionsInt("-ts_monitor_draw_solution_function","Monitor solution provided by TSMonitorSetSolutionFunction() graphically","TSMonitorDrawSolutionFunction",howoften,&howoften,NULL);CHKERRQ(ierr);
306     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,"Solution provided by user function",PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
307     ierr = TSMonitorSet(ts,TSMonitorDrawSolutionFunction,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
308   }
309 
310   opt  = PETSC_FALSE;
311   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);
312   if (flg) {
313     const char *ptr,*ptr2;
314     char       *filetemplate;
315     if (!monfilename[0]) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"-ts_monitor_solution_vtk requires a file template, e.g. filename-%%03D.vts");
316     /* Do some cursory validation of the input. */
317     ierr = PetscStrstr(monfilename,"%",(char**)&ptr);CHKERRQ(ierr);
318     if (!ptr) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"-ts_monitor_solution_vtk requires a file template, e.g. filename-%%03D.vts");
319     for (ptr++; ptr && *ptr; ptr++) {
320       ierr = PetscStrchr("DdiouxX",*ptr,(char**)&ptr2);CHKERRQ(ierr);
321       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");
322       if (ptr2) break;
323     }
324     ierr = PetscStrallocpy(monfilename,&filetemplate);CHKERRQ(ierr);
325     ierr = TSMonitorSet(ts,TSMonitorSolutionVTK,filetemplate,(PetscErrorCode (*)(void**))TSMonitorSolutionVTKDestroy);CHKERRQ(ierr);
326   }
327 
328   ierr = PetscOptionsString("-ts_monitor_dmda_ray","Display a ray of the solution","None","y=0",dir,16,&flg);CHKERRQ(ierr);
329   if (flg) {
330     TSMonitorDMDARayCtx *rayctx;
331     int                  ray = 0;
332     DMDADirection        ddir;
333     DM                   da;
334     PetscMPIInt          rank;
335 
336     if (dir[1] != '=') SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Unknown ray %s",dir);
337     if (dir[0] == 'x') ddir = DMDA_X;
338     else if (dir[0] == 'y') ddir = DMDA_Y;
339     else SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Unknown ray %s",dir);
340     sscanf(dir+2,"%d",&ray);
341 
342     ierr = PetscInfo2(((PetscObject)ts),"Displaying DMDA ray %c = %D\n",dir[0],ray);CHKERRQ(ierr);
343     ierr = PetscNew(&rayctx);CHKERRQ(ierr);
344     ierr = TSGetDM(ts,&da);CHKERRQ(ierr);
345     ierr = DMDAGetRay(da,ddir,ray,&rayctx->ray,&rayctx->scatter);CHKERRQ(ierr);
346     ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)ts),&rank);CHKERRQ(ierr);
347     if (!rank) {
348       ierr = PetscViewerDrawOpen(PETSC_COMM_SELF,0,0,0,0,600,300,&rayctx->viewer);CHKERRQ(ierr);
349     }
350     rayctx->lgctx = NULL;
351     ierr = TSMonitorSet(ts,TSMonitorDMDARay,rayctx,TSMonitorDMDARayDestroy);CHKERRQ(ierr);
352   }
353   ierr = PetscOptionsString("-ts_monitor_lg_dmda_ray","Display a ray of the solution","None","x=0",dir,16,&flg);CHKERRQ(ierr);
354   if (flg) {
355     TSMonitorDMDARayCtx *rayctx;
356     int                 ray = 0;
357     DMDADirection       ddir;
358     DM                  da;
359     PetscInt            howoften = 1;
360 
361     if (dir[1] != '=') SETERRQ1(PetscObjectComm((PetscObject) ts), PETSC_ERR_ARG_WRONG, "Malformed ray %s", dir);
362     if      (dir[0] == 'x') ddir = DMDA_X;
363     else if (dir[0] == 'y') ddir = DMDA_Y;
364     else SETERRQ1(PetscObjectComm((PetscObject) ts), PETSC_ERR_ARG_WRONG, "Unknown ray direction %s", dir);
365     sscanf(dir+2, "%d", &ray);
366 
367     ierr = PetscInfo2(((PetscObject) ts),"Displaying LG DMDA ray %c = %D\n", dir[0], ray);CHKERRQ(ierr);
368     ierr = PetscNew(&rayctx);CHKERRQ(ierr);
369     ierr = TSGetDM(ts, &da);CHKERRQ(ierr);
370     ierr = DMDAGetRay(da, ddir, ray, &rayctx->ray, &rayctx->scatter);CHKERRQ(ierr);
371     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,600,400,howoften,&rayctx->lgctx);CHKERRQ(ierr);
372     ierr = TSMonitorSet(ts, TSMonitorLGDMDARay, rayctx, TSMonitorDMDARayDestroy);CHKERRQ(ierr);
373   }
374 
375   ierr = PetscOptionsName("-ts_monitor_envelope","Monitor maximum and minimum value of each component of the solution","TSMonitorEnvelope",&opt);CHKERRQ(ierr);
376   if (opt) {
377     TSMonitorEnvelopeCtx ctx;
378 
379     ierr = TSMonitorEnvelopeCtxCreate(ts,&ctx);CHKERRQ(ierr);
380     ierr = TSMonitorSet(ts,TSMonitorEnvelope,ctx,(PetscErrorCode (*)(void**))TSMonitorEnvelopeCtxDestroy);CHKERRQ(ierr);
381   }
382 
383   flg  = PETSC_FALSE;
384   ierr = PetscOptionsBool("-ts_fd_color", "Use finite differences with coloring to compute IJacobian", "TSComputeJacobianDefaultColor", flg, &flg, NULL);CHKERRQ(ierr);
385   if (flg) {
386     DM   dm;
387     DMTS tdm;
388 
389     ierr = TSGetDM(ts, &dm);CHKERRQ(ierr);
390     ierr = DMGetDMTS(dm, &tdm);CHKERRQ(ierr);
391     tdm->ijacobianctx = NULL;
392     ierr = TSSetIJacobian(ts, NULL, NULL, TSComputeIJacobianDefaultColor, 0);CHKERRQ(ierr);
393     ierr = PetscInfo(ts, "Setting default finite difference coloring Jacobian matrix\n");CHKERRQ(ierr);
394   }
395 
396   /* Handle specific TS options */
397   if (ts->ops->setfromoptions) {
398     ierr = (*ts->ops->setfromoptions)(PetscOptionsObject,ts);CHKERRQ(ierr);
399   }
400 
401   /* Handle TSAdapt options */
402   ierr = TSGetAdapt(ts,&ts->adapt);CHKERRQ(ierr);
403   ierr = TSAdaptSetDefaultType(ts->adapt,ts->default_adapt_type);CHKERRQ(ierr);
404   ierr = TSAdaptSetFromOptions(PetscOptionsObject,ts->adapt);CHKERRQ(ierr);
405 
406   /* TS trajectory must be set after TS, since it may use some TS options above */
407   tflg = ts->trajectory ? PETSC_TRUE : PETSC_FALSE;
408   ierr = PetscOptionsBool("-ts_save_trajectory","Save the solution at each timestep","TSSetSaveTrajectory",tflg,&tflg,NULL);CHKERRQ(ierr);
409   if (tflg) {
410     ierr = TSSetSaveTrajectory(ts);CHKERRQ(ierr);
411   }
412 
413   ierr = TSAdjointSetFromOptions(PetscOptionsObject,ts);CHKERRQ(ierr);
414 
415   /* process any options handlers added with PetscObjectAddOptionsHandler() */
416   ierr = PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)ts);CHKERRQ(ierr);
417   ierr = PetscOptionsEnd();CHKERRQ(ierr);
418 
419   if (ts->trajectory) {
420     ierr = TSTrajectorySetFromOptions(ts->trajectory,ts);CHKERRQ(ierr);
421   }
422 
423   /* why do we have to do this here and not during TSSetUp? */
424   ierr = TSGetSNES(ts,&ts->snes);CHKERRQ(ierr);
425   if (ts->problem_type == TS_LINEAR) {
426     ierr = PetscObjectTypeCompareAny((PetscObject)ts->snes,&flg,SNESKSPONLY,SNESKSPTRANSPOSEONLY,"");CHKERRQ(ierr);
427     if (!flg) { ierr = SNESSetType(ts->snes,SNESKSPONLY);CHKERRQ(ierr); }
428   }
429   ierr = SNESSetFromOptions(ts->snes);CHKERRQ(ierr);
430   PetscFunctionReturn(0);
431 }
432 
433 /*@
434    TSGetTrajectory - Gets the trajectory from a TS if it exists
435 
436    Collective on TS
437 
438    Input Parameters:
439 .  ts - the TS context obtained from TSCreate()
440 
441    Output Parameters;
442 .  tr - the TSTrajectory object, if it exists
443 
444    Note: This routine should be called after all TS options have been set
445 
446    Level: advanced
447 
448 .seealso: TSGetTrajectory(), TSAdjointSolve(), TSTrajectory, TSTrajectoryCreate()
449 
450 .keywords: TS, set, checkpoint,
451 @*/
452 PetscErrorCode  TSGetTrajectory(TS ts,TSTrajectory *tr)
453 {
454   PetscFunctionBegin;
455   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
456   *tr = ts->trajectory;
457   PetscFunctionReturn(0);
458 }
459 
460 /*@
461    TSSetSaveTrajectory - Causes the TS to save its solutions as it iterates forward in time in a TSTrajectory object
462 
463    Collective on TS
464 
465    Input Parameters:
466 .  ts - the TS context obtained from TSCreate()
467 
468    Options Database:
469 +  -ts_save_trajectory - saves the trajectory to a file
470 -  -ts_trajectory_type type
471 
472 Note: This routine should be called after all TS options have been set
473 
474     The TSTRAJECTORYVISUALIZATION files can be loaded into Python with $PETSC_DIR/lib/petsc/bin/PetscBinaryIOTrajectory.py and
475    MATLAB with $PETSC_DIR/share/petsc/matlab/PetscReadBinaryTrajectory.m
476 
477    Level: intermediate
478 
479 .seealso: TSGetTrajectory(), TSAdjointSolve()
480 
481 .keywords: TS, set, checkpoint,
482 @*/
483 PetscErrorCode  TSSetSaveTrajectory(TS ts)
484 {
485   PetscErrorCode ierr;
486 
487   PetscFunctionBegin;
488   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
489   if (!ts->trajectory) {
490     ierr = TSTrajectoryCreate(PetscObjectComm((PetscObject)ts),&ts->trajectory);CHKERRQ(ierr);
491   }
492   PetscFunctionReturn(0);
493 }
494 
495 /*@
496    TSResetTrajectory - Destroys and recreates the internal TSTrajectory object
497 
498    Collective on TS
499 
500    Input Parameters:
501 .  ts - the TS context obtained from TSCreate()
502 
503    Level: intermediate
504 
505 .seealso: TSGetTrajectory(), TSAdjointSolve()
506 
507 .keywords: TS, set, checkpoint,
508 @*/
509 PetscErrorCode  TSResetTrajectory(TS ts)
510 {
511   PetscErrorCode ierr;
512 
513   PetscFunctionBegin;
514   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
515   if (ts->trajectory) {
516     ierr = TSTrajectoryDestroy(&ts->trajectory);CHKERRQ(ierr);
517     ierr = TSTrajectoryCreate(PetscObjectComm((PetscObject)ts),&ts->trajectory);CHKERRQ(ierr);
518   }
519   PetscFunctionReturn(0);
520 }
521 
522 /*@
523    TSComputeRHSJacobian - Computes the Jacobian matrix that has been
524       set with TSSetRHSJacobian().
525 
526    Collective on TS and Vec
527 
528    Input Parameters:
529 +  ts - the TS context
530 .  t - current timestep
531 -  U - input vector
532 
533    Output Parameters:
534 +  A - Jacobian matrix
535 .  B - optional preconditioning matrix
536 -  flag - flag indicating matrix structure
537 
538    Notes:
539    Most users should not need to explicitly call this routine, as it
540    is used internally within the nonlinear solvers.
541 
542    See KSPSetOperators() for important information about setting the
543    flag parameter.
544 
545    Level: developer
546 
547 .keywords: SNES, compute, Jacobian, matrix
548 
549 .seealso:  TSSetRHSJacobian(), KSPSetOperators()
550 @*/
551 PetscErrorCode  TSComputeRHSJacobian(TS ts,PetscReal t,Vec U,Mat A,Mat B)
552 {
553   PetscErrorCode   ierr;
554   PetscObjectState Ustate;
555   PetscObjectId    Uid;
556   DM               dm;
557   DMTS             tsdm;
558   TSRHSJacobian    rhsjacobianfunc;
559   void             *ctx;
560   TSIJacobian      ijacobianfunc;
561   TSRHSFunction    rhsfunction;
562 
563   PetscFunctionBegin;
564   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
565   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
566   PetscCheckSameComm(ts,1,U,3);
567   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
568   ierr = DMGetDMTS(dm,&tsdm);CHKERRQ(ierr);
569   ierr = DMTSGetRHSJacobian(dm,&rhsjacobianfunc,&ctx);CHKERRQ(ierr);
570   ierr = DMTSGetIJacobian(dm,&ijacobianfunc,NULL);CHKERRQ(ierr);
571   ierr = DMTSGetRHSFunction(dm,&rhsfunction,&ctx);CHKERRQ(ierr);
572   ierr = PetscObjectStateGet((PetscObject)U,&Ustate);CHKERRQ(ierr);
573   ierr = PetscObjectGetId((PetscObject)U,&Uid);CHKERRQ(ierr);
574 
575   if (ts->rhsjacobian.time == t && (ts->problem_type == TS_LINEAR || (ts->rhsjacobian.Xid == Uid && ts->rhsjacobian.Xstate == Ustate)) && (rhsfunction != TSComputeRHSFunctionLinear)) {
576     /* restore back RHS Jacobian matrices if they have been shifted/scaled */
577     if (A == ts->Arhs) {
578       if (ts->rhsjacobian.shift != 0) {
579         ierr = MatShift(A,-ts->rhsjacobian.shift);CHKERRQ(ierr);
580       }
581       if (ts->rhsjacobian.scale != 1.) {
582         ierr = MatScale(A,1./ts->rhsjacobian.scale);CHKERRQ(ierr);
583       }
584     }
585     if (B && B == ts->Brhs && A != B) {
586       if (ts->rhsjacobian.shift != 0) {
587         ierr = MatShift(B,-ts->rhsjacobian.shift);CHKERRQ(ierr);
588       }
589       if (ts->rhsjacobian.scale != 1.) {
590         ierr = MatScale(B,1./ts->rhsjacobian.scale);CHKERRQ(ierr);
591       }
592     }
593     ts->rhsjacobian.shift = 0;
594     ts->rhsjacobian.scale = 1.;
595     PetscFunctionReturn(0);
596   }
597 
598   if (!rhsjacobianfunc && !ijacobianfunc) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSJacobian() and / or TSSetIJacobian()");
599 
600   if (ts->rhsjacobian.reuse) {
601     if (A == ts->Arhs) {
602       /* MatScale has a short path for this case.
603          However, this code path is taken the first time TSComputeRHSJacobian is called
604          and the matrices have not assembled yet */
605       if (ts->rhsjacobian.shift != 0) {
606         ierr = MatShift(A,-ts->rhsjacobian.shift);CHKERRQ(ierr);
607       }
608       if (ts->rhsjacobian.scale != 1.) {
609         ierr = MatScale(A,1./ts->rhsjacobian.scale);CHKERRQ(ierr);
610       }
611     }
612     if (B && B == ts->Brhs && A != B) {
613       if (ts->rhsjacobian.shift != 0) {
614         ierr = MatShift(B,-ts->rhsjacobian.shift);CHKERRQ(ierr);
615       }
616       if (ts->rhsjacobian.scale != 1.) {
617         ierr = MatScale(B,1./ts->rhsjacobian.scale);CHKERRQ(ierr);
618       }
619     }
620   }
621 
622   if (rhsjacobianfunc) {
623     PetscBool missing;
624     ierr = PetscLogEventBegin(TS_JacobianEval,ts,U,A,B);CHKERRQ(ierr);
625     PetscStackPush("TS user Jacobian function");
626     ierr = (*rhsjacobianfunc)(ts,t,U,A,B,ctx);CHKERRQ(ierr);
627     PetscStackPop;
628     ierr = PetscLogEventEnd(TS_JacobianEval,ts,U,A,B);CHKERRQ(ierr);
629     if (A) {
630       ierr = MatMissingDiagonal(A,&missing,NULL);CHKERRQ(ierr);
631       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");
632     }
633     if (B && B != A) {
634       ierr = MatMissingDiagonal(B,&missing,NULL);CHKERRQ(ierr);
635       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");
636     }
637   } else {
638     ierr = MatZeroEntries(A);CHKERRQ(ierr);
639     if (B && A != B) {ierr = MatZeroEntries(B);CHKERRQ(ierr);}
640   }
641   ts->rhsjacobian.time  = t;
642   ts->rhsjacobian.shift = 0;
643   ts->rhsjacobian.scale = 1.;
644   ierr                  = PetscObjectGetId((PetscObject)U,&ts->rhsjacobian.Xid);CHKERRQ(ierr);
645   ierr                  = PetscObjectStateGet((PetscObject)U,&ts->rhsjacobian.Xstate);CHKERRQ(ierr);
646   PetscFunctionReturn(0);
647 }
648 
649 /*@
650    TSComputeRHSFunction - Evaluates the right-hand-side function.
651 
652    Collective on TS and Vec
653 
654    Input Parameters:
655 +  ts - the TS context
656 .  t - current time
657 -  U - state vector
658 
659    Output Parameter:
660 .  y - right hand side
661 
662    Note:
663    Most users should not need to explicitly call this routine, as it
664    is used internally within the nonlinear solvers.
665 
666    Level: developer
667 
668 .keywords: TS, compute
669 
670 .seealso: TSSetRHSFunction(), TSComputeIFunction()
671 @*/
672 PetscErrorCode TSComputeRHSFunction(TS ts,PetscReal t,Vec U,Vec y)
673 {
674   PetscErrorCode ierr;
675   TSRHSFunction  rhsfunction;
676   TSIFunction    ifunction;
677   void           *ctx;
678   DM             dm;
679 
680   PetscFunctionBegin;
681   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
682   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
683   PetscValidHeaderSpecific(y,VEC_CLASSID,4);
684   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
685   ierr = DMTSGetRHSFunction(dm,&rhsfunction,&ctx);CHKERRQ(ierr);
686   ierr = DMTSGetIFunction(dm,&ifunction,NULL);CHKERRQ(ierr);
687 
688   if (!rhsfunction && !ifunction) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSFunction() and / or TSSetIFunction()");
689 
690   ierr = PetscLogEventBegin(TS_FunctionEval,ts,U,y,0);CHKERRQ(ierr);
691   if (rhsfunction) {
692     PetscStackPush("TS user right-hand-side function");
693     ierr = (*rhsfunction)(ts,t,U,y,ctx);CHKERRQ(ierr);
694     PetscStackPop;
695   } else {
696     ierr = VecZeroEntries(y);CHKERRQ(ierr);
697   }
698 
699   ierr = PetscLogEventEnd(TS_FunctionEval,ts,U,y,0);CHKERRQ(ierr);
700   PetscFunctionReturn(0);
701 }
702 
703 /*@
704    TSComputeSolutionFunction - Evaluates the solution function.
705 
706    Collective on TS and Vec
707 
708    Input Parameters:
709 +  ts - the TS context
710 -  t - current time
711 
712    Output Parameter:
713 .  U - the solution
714 
715    Note:
716    Most users should not need to explicitly call this routine, as it
717    is used internally within the nonlinear solvers.
718 
719    Level: developer
720 
721 .keywords: TS, compute
722 
723 .seealso: TSSetSolutionFunction(), TSSetRHSFunction(), TSComputeIFunction()
724 @*/
725 PetscErrorCode TSComputeSolutionFunction(TS ts,PetscReal t,Vec U)
726 {
727   PetscErrorCode     ierr;
728   TSSolutionFunction solutionfunction;
729   void               *ctx;
730   DM                 dm;
731 
732   PetscFunctionBegin;
733   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
734   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
735   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
736   ierr = DMTSGetSolutionFunction(dm,&solutionfunction,&ctx);CHKERRQ(ierr);
737 
738   if (solutionfunction) {
739     PetscStackPush("TS user solution function");
740     ierr = (*solutionfunction)(ts,t,U,ctx);CHKERRQ(ierr);
741     PetscStackPop;
742   }
743   PetscFunctionReturn(0);
744 }
745 /*@
746    TSComputeForcingFunction - Evaluates the forcing function.
747 
748    Collective on TS and Vec
749 
750    Input Parameters:
751 +  ts - the TS context
752 -  t - current time
753 
754    Output Parameter:
755 .  U - the function value
756 
757    Note:
758    Most users should not need to explicitly call this routine, as it
759    is used internally within the nonlinear solvers.
760 
761    Level: developer
762 
763 .keywords: TS, compute
764 
765 .seealso: TSSetSolutionFunction(), TSSetRHSFunction(), TSComputeIFunction()
766 @*/
767 PetscErrorCode TSComputeForcingFunction(TS ts,PetscReal t,Vec U)
768 {
769   PetscErrorCode     ierr, (*forcing)(TS,PetscReal,Vec,void*);
770   void               *ctx;
771   DM                 dm;
772 
773   PetscFunctionBegin;
774   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
775   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
776   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
777   ierr = DMTSGetForcingFunction(dm,&forcing,&ctx);CHKERRQ(ierr);
778 
779   if (forcing) {
780     PetscStackPush("TS user forcing function");
781     ierr = (*forcing)(ts,t,U,ctx);CHKERRQ(ierr);
782     PetscStackPop;
783   }
784   PetscFunctionReturn(0);
785 }
786 
787 static PetscErrorCode TSGetRHSVec_Private(TS ts,Vec *Frhs)
788 {
789   Vec            F;
790   PetscErrorCode ierr;
791 
792   PetscFunctionBegin;
793   *Frhs = NULL;
794   ierr  = TSGetIFunction(ts,&F,NULL,NULL);CHKERRQ(ierr);
795   if (!ts->Frhs) {
796     ierr = VecDuplicate(F,&ts->Frhs);CHKERRQ(ierr);
797   }
798   *Frhs = ts->Frhs;
799   PetscFunctionReturn(0);
800 }
801 
802 PetscErrorCode TSGetRHSMats_Private(TS ts,Mat *Arhs,Mat *Brhs)
803 {
804   Mat            A,B;
805   PetscErrorCode ierr;
806   TSIJacobian    ijacobian;
807 
808   PetscFunctionBegin;
809   if (Arhs) *Arhs = NULL;
810   if (Brhs) *Brhs = NULL;
811   ierr = TSGetIJacobian(ts,&A,&B,&ijacobian,NULL);CHKERRQ(ierr);
812   if (Arhs) {
813     if (!ts->Arhs) {
814       if (ijacobian) {
815         ierr = MatDuplicate(A,MAT_DO_NOT_COPY_VALUES,&ts->Arhs);CHKERRQ(ierr);
816       } else {
817         ts->Arhs = A;
818         ierr = PetscObjectReference((PetscObject)A);CHKERRQ(ierr);
819       }
820     } else {
821       PetscBool flg;
822       ierr = SNESGetUseMatrixFree(ts->snes,NULL,&flg);CHKERRQ(ierr);
823       /* Handle case where user provided only RHSJacobian and used -snes_mf_operator */
824       if (flg && !ijacobian && ts->Arhs == ts->Brhs){
825         ierr = PetscObjectDereference((PetscObject)ts->Arhs);CHKERRQ(ierr);
826         ts->Arhs = A;
827         ierr = PetscObjectReference((PetscObject)A);CHKERRQ(ierr);
828       }
829     }
830     *Arhs = ts->Arhs;
831   }
832   if (Brhs) {
833     if (!ts->Brhs) {
834       if (A != B) {
835         if (ijacobian) {
836           ierr = MatDuplicate(B,MAT_DO_NOT_COPY_VALUES,&ts->Brhs);CHKERRQ(ierr);
837         } else {
838           ts->Brhs = B;
839           ierr = PetscObjectReference((PetscObject)B);CHKERRQ(ierr);
840         }
841       } else {
842         ierr = PetscObjectReference((PetscObject)ts->Arhs);CHKERRQ(ierr);
843         ts->Brhs = ts->Arhs;
844       }
845     }
846     *Brhs = ts->Brhs;
847   }
848   PetscFunctionReturn(0);
849 }
850 
851 /*@
852    TSComputeIFunction - Evaluates the DAE residual written in implicit form F(t,U,Udot)=0
853 
854    Collective on TS and Vec
855 
856    Input Parameters:
857 +  ts - the TS context
858 .  t - current time
859 .  U - state vector
860 .  Udot - time derivative of state vector
861 -  imex - flag indicates if the method is IMEX so that the RHSFunction should be kept separate
862 
863    Output Parameter:
864 .  Y - right hand side
865 
866    Note:
867    Most users should not need to explicitly call this routine, as it
868    is used internally within the nonlinear solvers.
869 
870    If the user did did not write their equations in implicit form, this
871    function recasts them in implicit form.
872 
873    Level: developer
874 
875 .keywords: TS, compute
876 
877 .seealso: TSSetIFunction(), TSComputeRHSFunction()
878 @*/
879 PetscErrorCode TSComputeIFunction(TS ts,PetscReal t,Vec U,Vec Udot,Vec Y,PetscBool imex)
880 {
881   PetscErrorCode ierr;
882   TSIFunction    ifunction;
883   TSRHSFunction  rhsfunction;
884   void           *ctx;
885   DM             dm;
886 
887   PetscFunctionBegin;
888   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
889   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
890   PetscValidHeaderSpecific(Udot,VEC_CLASSID,4);
891   PetscValidHeaderSpecific(Y,VEC_CLASSID,5);
892 
893   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
894   ierr = DMTSGetIFunction(dm,&ifunction,&ctx);CHKERRQ(ierr);
895   ierr = DMTSGetRHSFunction(dm,&rhsfunction,NULL);CHKERRQ(ierr);
896 
897   if (!rhsfunction && !ifunction) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSFunction() and / or TSSetIFunction()");
898 
899   ierr = PetscLogEventBegin(TS_FunctionEval,ts,U,Udot,Y);CHKERRQ(ierr);
900   if (ifunction) {
901     PetscStackPush("TS user implicit function");
902     ierr = (*ifunction)(ts,t,U,Udot,Y,ctx);CHKERRQ(ierr);
903     PetscStackPop;
904   }
905   if (imex) {
906     if (!ifunction) {
907       ierr = VecCopy(Udot,Y);CHKERRQ(ierr);
908     }
909   } else if (rhsfunction) {
910     if (ifunction) {
911       Vec Frhs;
912       ierr = TSGetRHSVec_Private(ts,&Frhs);CHKERRQ(ierr);
913       ierr = TSComputeRHSFunction(ts,t,U,Frhs);CHKERRQ(ierr);
914       ierr = VecAXPY(Y,-1,Frhs);CHKERRQ(ierr);
915     } else {
916       ierr = TSComputeRHSFunction(ts,t,U,Y);CHKERRQ(ierr);
917       ierr = VecAYPX(Y,-1,Udot);CHKERRQ(ierr);
918     }
919   }
920   ierr = PetscLogEventEnd(TS_FunctionEval,ts,U,Udot,Y);CHKERRQ(ierr);
921   PetscFunctionReturn(0);
922 }
923 
924 /*@
925    TSComputeIJacobian - Evaluates the Jacobian of the DAE
926 
927    Collective on TS and Vec
928 
929    Input
930       Input Parameters:
931 +  ts - the TS context
932 .  t - current timestep
933 .  U - state vector
934 .  Udot - time derivative of state vector
935 .  shift - shift to apply, see note below
936 -  imex - flag indicates if the method is IMEX so that the RHSJacobian should be kept separate
937 
938    Output Parameters:
939 +  A - Jacobian matrix
940 -  B - matrix from which the preconditioner is constructed; often the same as A
941 
942    Notes:
943    If F(t,U,Udot)=0 is the DAE, the required Jacobian is
944 
945    dF/dU + shift*dF/dUdot
946 
947    Most users should not need to explicitly call this routine, as it
948    is used internally within the nonlinear solvers.
949 
950    Level: developer
951 
952 .keywords: TS, compute, Jacobian, matrix
953 
954 .seealso:  TSSetIJacobian()
955 @*/
956 PetscErrorCode TSComputeIJacobian(TS ts,PetscReal t,Vec U,Vec Udot,PetscReal shift,Mat A,Mat B,PetscBool imex)
957 {
958   PetscErrorCode ierr;
959   TSIJacobian    ijacobian;
960   TSRHSJacobian  rhsjacobian;
961   DM             dm;
962   void           *ctx;
963 
964   PetscFunctionBegin;
965   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
966   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
967   PetscValidHeaderSpecific(Udot,VEC_CLASSID,4);
968   PetscValidPointer(A,6);
969   PetscValidHeaderSpecific(A,MAT_CLASSID,6);
970   PetscValidPointer(B,7);
971   PetscValidHeaderSpecific(B,MAT_CLASSID,7);
972 
973   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
974   ierr = DMTSGetIJacobian(dm,&ijacobian,&ctx);CHKERRQ(ierr);
975   ierr = DMTSGetRHSJacobian(dm,&rhsjacobian,NULL);CHKERRQ(ierr);
976 
977   if (!rhsjacobian && !ijacobian) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSJacobian() and / or TSSetIJacobian()");
978 
979   ierr = PetscLogEventBegin(TS_JacobianEval,ts,U,A,B);CHKERRQ(ierr);
980   if (ijacobian) {
981     PetscBool missing;
982     PetscStackPush("TS user implicit Jacobian");
983     ierr = (*ijacobian)(ts,t,U,Udot,shift,A,B,ctx);CHKERRQ(ierr);
984     PetscStackPop;
985     ierr = MatMissingDiagonal(A,&missing,NULL);CHKERRQ(ierr);
986     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");
987     if (B != A) {
988       ierr = MatMissingDiagonal(B,&missing,NULL);CHKERRQ(ierr);
989       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");
990     }
991   }
992   if (imex) {
993     if (!ijacobian) {  /* system was written as Udot = G(t,U) */
994       PetscBool assembled;
995       if (rhsjacobian) {
996         Mat Arhs = NULL;
997         ierr = TSGetRHSMats_Private(ts,&Arhs,NULL);CHKERRQ(ierr);
998         if (A == Arhs) {
999           if (rhsjacobian == TSComputeRHSJacobianConstant) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Unsupported operation! cannot use TSComputeRHSJacobianConstant");
1000           ts->rhsjacobian.time = PETSC_MIN_REAL;
1001         }
1002       }
1003       ierr = MatZeroEntries(A);CHKERRQ(ierr);
1004       ierr = MatAssembled(A,&assembled);CHKERRQ(ierr);
1005       if (!assembled) {
1006         ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1007         ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1008       }
1009       ierr = MatShift(A,shift);CHKERRQ(ierr);
1010       if (A != B) {
1011         ierr = MatZeroEntries(B);CHKERRQ(ierr);
1012         ierr = MatAssembled(B,&assembled);CHKERRQ(ierr);
1013         if (!assembled) {
1014           ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1015           ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1016         }
1017         ierr = MatShift(B,shift);CHKERRQ(ierr);
1018       }
1019     }
1020   } else {
1021     Mat Arhs = NULL,Brhs = NULL;
1022     if (rhsjacobian) {
1023       ierr = TSGetRHSMats_Private(ts,&Arhs,&Brhs);CHKERRQ(ierr);
1024       ierr = TSComputeRHSJacobian(ts,t,U,Arhs,Brhs);CHKERRQ(ierr);
1025     }
1026     if (Arhs == A) {           /* No IJacobian, so we only have the RHS matrix */
1027       PetscBool flg;
1028       ts->rhsjacobian.scale = -1;
1029       ts->rhsjacobian.shift = shift;
1030       ierr = SNESGetUseMatrixFree(ts->snes,NULL,&flg);CHKERRQ(ierr);
1031       /* since -snes_mf_operator uses the full SNES function it does not need to be shifted or scaled here */
1032       if (!flg) {
1033         ierr = MatScale(A,-1);CHKERRQ(ierr);
1034         ierr = MatShift(A,shift);CHKERRQ(ierr);
1035       }
1036       if (A != B) {
1037         ierr = MatScale(B,-1);CHKERRQ(ierr);
1038         ierr = MatShift(B,shift);CHKERRQ(ierr);
1039       }
1040     } else if (Arhs) {          /* Both IJacobian and RHSJacobian */
1041       MatStructure axpy = DIFFERENT_NONZERO_PATTERN;
1042       if (!ijacobian) {         /* No IJacobian provided, but we have a separate RHS matrix */
1043         ierr = MatZeroEntries(A);CHKERRQ(ierr);
1044         ierr = MatShift(A,shift);CHKERRQ(ierr);
1045         if (A != B) {
1046           ierr = MatZeroEntries(B);CHKERRQ(ierr);
1047           ierr = MatShift(B,shift);CHKERRQ(ierr);
1048         }
1049       }
1050       ierr = MatAXPY(A,-1,Arhs,axpy);CHKERRQ(ierr);
1051       if (A != B) {
1052         ierr = MatAXPY(B,-1,Brhs,axpy);CHKERRQ(ierr);
1053       }
1054     }
1055   }
1056   ierr = PetscLogEventEnd(TS_JacobianEval,ts,U,A,B);CHKERRQ(ierr);
1057   PetscFunctionReturn(0);
1058 }
1059 
1060 /*@C
1061     TSSetRHSFunction - Sets the routine for evaluating the function,
1062     where U_t = G(t,u).
1063 
1064     Logically Collective on TS
1065 
1066     Input Parameters:
1067 +   ts - the TS context obtained from TSCreate()
1068 .   r - vector to put the computed right hand side (or NULL to have it created)
1069 .   f - routine for evaluating the right-hand-side 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,Vec F,void *ctx);
1075 
1076 +   t - current timestep
1077 .   u - input vector
1078 .   F - function vector
1079 -   ctx - [optional] user-defined function context
1080 
1081     Level: beginner
1082 
1083     Notes:
1084     You must call this function or TSSetIFunction() to define your ODE. You cannot use this function when solving a DAE.
1085 
1086 .keywords: TS, timestep, set, right-hand-side, function
1087 
1088 .seealso: TSSetRHSJacobian(), TSSetIJacobian(), TSSetIFunction()
1089 @*/
1090 PetscErrorCode  TSSetRHSFunction(TS ts,Vec r,PetscErrorCode (*f)(TS,PetscReal,Vec,Vec,void*),void *ctx)
1091 {
1092   PetscErrorCode ierr;
1093   SNES           snes;
1094   Vec            ralloc = NULL;
1095   DM             dm;
1096 
1097   PetscFunctionBegin;
1098   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1099   if (r) PetscValidHeaderSpecific(r,VEC_CLASSID,2);
1100 
1101   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1102   ierr = DMTSSetRHSFunction(dm,f,ctx);CHKERRQ(ierr);
1103   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1104   if (!r && !ts->dm && ts->vec_sol) {
1105     ierr = VecDuplicate(ts->vec_sol,&ralloc);CHKERRQ(ierr);
1106     r = ralloc;
1107   }
1108   ierr = SNESSetFunction(snes,r,SNESTSFormFunction,ts);CHKERRQ(ierr);
1109   ierr = VecDestroy(&ralloc);CHKERRQ(ierr);
1110   PetscFunctionReturn(0);
1111 }
1112 
1113 /*@C
1114     TSSetSolutionFunction - Provide a function that computes the solution of the ODE or DAE
1115 
1116     Logically Collective on TS
1117 
1118     Input Parameters:
1119 +   ts - the TS context obtained from TSCreate()
1120 .   f - routine for evaluating the solution
1121 -   ctx - [optional] user-defined context for private data for the
1122           function evaluation routine (may be NULL)
1123 
1124     Calling sequence of func:
1125 $     func (TS ts,PetscReal t,Vec u,void *ctx);
1126 
1127 +   t - current timestep
1128 .   u - output vector
1129 -   ctx - [optional] user-defined function context
1130 
1131     Options Database:
1132 +  -ts_monitor_lg_error - create a graphical monitor of error history, requires user to have provided TSSetSolutionFunction()
1133 -  -ts_monitor_draw_error - Monitor error graphically, requires user to have provided TSSetSolutionFunction()
1134 
1135     Notes:
1136     This routine is used for testing accuracy of time integration schemes when you already know the solution.
1137     If analytic solutions are not known for your system, consider using the Method of Manufactured Solutions to
1138     create closed-form solutions with non-physical forcing terms.
1139 
1140     For low-dimensional problems solved in serial, such as small discrete systems, TSMonitorLGError() can be used to monitor the error history.
1141 
1142     Level: beginner
1143 
1144 .keywords: TS, timestep, set, right-hand-side, function
1145 
1146 .seealso: TSSetRHSJacobian(), TSSetIJacobian(), TSComputeSolutionFunction(), TSSetForcingFunction(), TSSetSolution(), TSGetSolution(), TSMonitorLGError(), TSMonitorDrawError()
1147 @*/
1148 PetscErrorCode  TSSetSolutionFunction(TS ts,PetscErrorCode (*f)(TS,PetscReal,Vec,void*),void *ctx)
1149 {
1150   PetscErrorCode ierr;
1151   DM             dm;
1152 
1153   PetscFunctionBegin;
1154   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1155   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1156   ierr = DMTSSetSolutionFunction(dm,f,ctx);CHKERRQ(ierr);
1157   PetscFunctionReturn(0);
1158 }
1159 
1160 /*@C
1161     TSSetForcingFunction - Provide a function that computes a forcing term for a ODE or PDE
1162 
1163     Logically Collective on TS
1164 
1165     Input Parameters:
1166 +   ts - the TS context obtained from TSCreate()
1167 .   func - routine for evaluating the forcing function
1168 -   ctx - [optional] user-defined context for private data for the
1169           function evaluation routine (may be NULL)
1170 
1171     Calling sequence of func:
1172 $     func (TS ts,PetscReal t,Vec f,void *ctx);
1173 
1174 +   t - current timestep
1175 .   f - output vector
1176 -   ctx - [optional] user-defined function context
1177 
1178     Notes:
1179     This routine is useful for testing accuracy of time integration schemes when using the Method of Manufactured Solutions to
1180     create closed-form solutions with a non-physical forcing term. It allows you to use the Method of Manufactored Solution without directly editing the
1181     definition of the problem you are solving and hence possibly introducing bugs.
1182 
1183     This replaces the ODE F(u,u_t,t) = 0 the TS is solving with F(u,u_t,t) - func(t) = 0
1184 
1185     This forcing function does not depend on the solution to the equations, it can only depend on spatial location, time, and possibly parameters, the
1186     parameters can be passed in the ctx variable.
1187 
1188     For low-dimensional problems solved in serial, such as small discrete systems, TSMonitorLGError() can be used to monitor the error history.
1189 
1190     Level: beginner
1191 
1192 .keywords: TS, timestep, set, right-hand-side, function
1193 
1194 .seealso: TSSetRHSJacobian(), TSSetIJacobian(), TSComputeSolutionFunction(), TSSetSolutionFunction()
1195 @*/
1196 PetscErrorCode  TSSetForcingFunction(TS ts,TSForcingFunction func,void *ctx)
1197 {
1198   PetscErrorCode ierr;
1199   DM             dm;
1200 
1201   PetscFunctionBegin;
1202   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1203   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1204   ierr = DMTSSetForcingFunction(dm,func,ctx);CHKERRQ(ierr);
1205   PetscFunctionReturn(0);
1206 }
1207 
1208 /*@C
1209    TSSetRHSJacobian - Sets the function to compute the Jacobian of G,
1210    where U_t = G(U,t), as well as the location to store the matrix.
1211 
1212    Logically Collective on TS
1213 
1214    Input Parameters:
1215 +  ts  - the TS context obtained from TSCreate()
1216 .  Amat - (approximate) Jacobian matrix
1217 .  Pmat - matrix from which preconditioner is to be constructed (usually the same as Amat)
1218 .  f   - the Jacobian evaluation routine
1219 -  ctx - [optional] user-defined context for private data for the
1220          Jacobian evaluation routine (may be NULL)
1221 
1222    Calling sequence of f:
1223 $     func (TS ts,PetscReal t,Vec u,Mat A,Mat B,void *ctx);
1224 
1225 +  t - current timestep
1226 .  u - input vector
1227 .  Amat - (approximate) Jacobian matrix
1228 .  Pmat - matrix from which preconditioner is to be constructed (usually the same as Amat)
1229 -  ctx - [optional] user-defined context for matrix evaluation routine
1230 
1231    Notes:
1232    You must set all the diagonal entries of the matrices, if they are zero you must still set them with a zero value
1233 
1234    The TS solver may modify the nonzero structure and the entries of the matrices Amat and Pmat between the calls to f()
1235    You should not assume the values are the same in the next call to f() as you set them in the previous call.
1236 
1237    Level: beginner
1238 
1239 .keywords: TS, timestep, set, right-hand-side, Jacobian
1240 
1241 .seealso: SNESComputeJacobianDefaultColor(), TSSetRHSFunction(), TSRHSJacobianSetReuse(), TSSetIJacobian()
1242 
1243 @*/
1244 PetscErrorCode  TSSetRHSJacobian(TS ts,Mat Amat,Mat Pmat,TSRHSJacobian f,void *ctx)
1245 {
1246   PetscErrorCode ierr;
1247   SNES           snes;
1248   DM             dm;
1249   TSIJacobian    ijacobian;
1250 
1251   PetscFunctionBegin;
1252   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1253   if (Amat) PetscValidHeaderSpecific(Amat,MAT_CLASSID,2);
1254   if (Pmat) PetscValidHeaderSpecific(Pmat,MAT_CLASSID,3);
1255   if (Amat) PetscCheckSameComm(ts,1,Amat,2);
1256   if (Pmat) PetscCheckSameComm(ts,1,Pmat,3);
1257 
1258   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1259   ierr = DMTSSetRHSJacobian(dm,f,ctx);CHKERRQ(ierr);
1260   if (f == TSComputeRHSJacobianConstant) {
1261     /* Handle this case automatically for the user; otherwise user should call themselves. */
1262     ierr = TSRHSJacobianSetReuse(ts,PETSC_TRUE);CHKERRQ(ierr);
1263   }
1264   ierr = DMTSGetIJacobian(dm,&ijacobian,NULL);CHKERRQ(ierr);
1265   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1266   if (!ijacobian) {
1267     ierr = SNESSetJacobian(snes,Amat,Pmat,SNESTSFormJacobian,ts);CHKERRQ(ierr);
1268   }
1269   if (Amat) {
1270     ierr = PetscObjectReference((PetscObject)Amat);CHKERRQ(ierr);
1271     ierr = MatDestroy(&ts->Arhs);CHKERRQ(ierr);
1272     ts->Arhs = Amat;
1273   }
1274   if (Pmat) {
1275     ierr = PetscObjectReference((PetscObject)Pmat);CHKERRQ(ierr);
1276     ierr = MatDestroy(&ts->Brhs);CHKERRQ(ierr);
1277     ts->Brhs = Pmat;
1278   }
1279   PetscFunctionReturn(0);
1280 }
1281 
1282 /*@C
1283    TSSetIFunction - Set the function to compute F(t,U,U_t) where F() = 0 is the DAE to be solved.
1284 
1285    Logically Collective on TS
1286 
1287    Input Parameters:
1288 +  ts  - the TS context obtained from TSCreate()
1289 .  r   - vector to hold the residual (or NULL to have it created internally)
1290 .  f   - the function evaluation routine
1291 -  ctx - user-defined context for private data for the function evaluation routine (may be NULL)
1292 
1293    Calling sequence of f:
1294 $  f(TS ts,PetscReal t,Vec u,Vec u_t,Vec F,ctx);
1295 
1296 +  t   - time at step/stage being solved
1297 .  u   - state vector
1298 .  u_t - time derivative of state vector
1299 .  F   - function vector
1300 -  ctx - [optional] user-defined context for matrix evaluation routine
1301 
1302    Important:
1303    The user MUST call either this routine or TSSetRHSFunction() to define the ODE.  When solving DAEs you must use this function.
1304 
1305    Level: beginner
1306 
1307 .keywords: TS, timestep, set, DAE, Jacobian
1308 
1309 .seealso: TSSetRHSJacobian(), TSSetRHSFunction(), TSSetIJacobian()
1310 @*/
1311 PetscErrorCode  TSSetIFunction(TS ts,Vec r,TSIFunction f,void *ctx)
1312 {
1313   PetscErrorCode ierr;
1314   SNES           snes;
1315   Vec            ralloc = NULL;
1316   DM             dm;
1317 
1318   PetscFunctionBegin;
1319   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1320   if (r) PetscValidHeaderSpecific(r,VEC_CLASSID,2);
1321 
1322   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1323   ierr = DMTSSetIFunction(dm,f,ctx);CHKERRQ(ierr);
1324 
1325   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1326   if (!r && !ts->dm && ts->vec_sol) {
1327     ierr = VecDuplicate(ts->vec_sol,&ralloc);CHKERRQ(ierr);
1328     r  = ralloc;
1329   }
1330   ierr = SNESSetFunction(snes,r,SNESTSFormFunction,ts);CHKERRQ(ierr);
1331   ierr = VecDestroy(&ralloc);CHKERRQ(ierr);
1332   PetscFunctionReturn(0);
1333 }
1334 
1335 /*@C
1336    TSGetIFunction - Returns the vector where the implicit residual is stored and the function/contex to compute it.
1337 
1338    Not Collective
1339 
1340    Input Parameter:
1341 .  ts - the TS context
1342 
1343    Output Parameter:
1344 +  r - vector to hold residual (or NULL)
1345 .  func - the function to compute residual (or NULL)
1346 -  ctx - the function context (or NULL)
1347 
1348    Level: advanced
1349 
1350 .keywords: TS, nonlinear, get, function
1351 
1352 .seealso: TSSetIFunction(), SNESGetFunction()
1353 @*/
1354 PetscErrorCode TSGetIFunction(TS ts,Vec *r,TSIFunction *func,void **ctx)
1355 {
1356   PetscErrorCode ierr;
1357   SNES           snes;
1358   DM             dm;
1359 
1360   PetscFunctionBegin;
1361   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1362   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1363   ierr = SNESGetFunction(snes,r,NULL,NULL);CHKERRQ(ierr);
1364   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1365   ierr = DMTSGetIFunction(dm,func,ctx);CHKERRQ(ierr);
1366   PetscFunctionReturn(0);
1367 }
1368 
1369 /*@C
1370    TSGetRHSFunction - Returns the vector where the right hand side is stored and the function/context to compute it.
1371 
1372    Not Collective
1373 
1374    Input Parameter:
1375 .  ts - the TS context
1376 
1377    Output Parameter:
1378 +  r - vector to hold computed right hand side (or NULL)
1379 .  func - the function to compute right hand side (or NULL)
1380 -  ctx - the function context (or NULL)
1381 
1382    Level: advanced
1383 
1384 .keywords: TS, nonlinear, get, function
1385 
1386 .seealso: TSSetRHSFunction(), SNESGetFunction()
1387 @*/
1388 PetscErrorCode TSGetRHSFunction(TS ts,Vec *r,TSRHSFunction *func,void **ctx)
1389 {
1390   PetscErrorCode ierr;
1391   SNES           snes;
1392   DM             dm;
1393 
1394   PetscFunctionBegin;
1395   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1396   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1397   ierr = SNESGetFunction(snes,r,NULL,NULL);CHKERRQ(ierr);
1398   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1399   ierr = DMTSGetRHSFunction(dm,func,ctx);CHKERRQ(ierr);
1400   PetscFunctionReturn(0);
1401 }
1402 
1403 /*@C
1404    TSSetIJacobian - Set the function to compute the matrix dF/dU + a*dF/dU_t where F(t,U,U_t) is the function
1405         provided with TSSetIFunction().
1406 
1407    Logically Collective on TS
1408 
1409    Input Parameters:
1410 +  ts  - the TS context obtained from TSCreate()
1411 .  Amat - (approximate) Jacobian matrix
1412 .  Pmat - matrix used to compute preconditioner (usually the same as Amat)
1413 .  f   - the Jacobian evaluation routine
1414 -  ctx - user-defined context for private data for the Jacobian evaluation routine (may be NULL)
1415 
1416    Calling sequence of f:
1417 $  f(TS ts,PetscReal t,Vec U,Vec U_t,PetscReal a,Mat Amat,Mat Pmat,void *ctx);
1418 
1419 +  t    - time at step/stage being solved
1420 .  U    - state vector
1421 .  U_t  - time derivative of state vector
1422 .  a    - shift
1423 .  Amat - (approximate) Jacobian of F(t,U,W+a*U), equivalent to dF/dU + a*dF/dU_t
1424 .  Pmat - matrix used for constructing preconditioner, usually the same as Amat
1425 -  ctx  - [optional] user-defined context for matrix evaluation routine
1426 
1427    Notes:
1428    The matrices Amat and Pmat are exactly the matrices that are used by SNES for the nonlinear solve.
1429 
1430    If you know the operator Amat has a null space you can use MatSetNullSpace() and MatSetTransposeNullSpace() to supply the null
1431    space to Amat and the KSP solvers will automatically use that null space as needed during the solution process.
1432 
1433    The matrix dF/dU + a*dF/dU_t you provide turns out to be
1434    the Jacobian of F(t,U,W+a*U) where F(t,U,U_t) = 0 is the DAE to be solved.
1435    The time integrator internally approximates U_t by W+a*U where the positive "shift"
1436    a and vector W depend on the integration method, step size, and past states. For example with
1437    the backward Euler method a = 1/dt and W = -a*U(previous timestep) so
1438    W + a*U = a*(U - U(previous timestep)) = (U - U(previous timestep))/dt
1439 
1440    You must set all the diagonal entries of the matrices, if they are zero you must still set them with a zero value
1441 
1442    The TS solver may modify the nonzero structure and the entries of the matrices Amat and Pmat between the calls to f()
1443    You should not assume the values are the same in the next call to f() as you set them in the previous call.
1444 
1445    Level: beginner
1446 
1447 .keywords: TS, timestep, DAE, Jacobian
1448 
1449 .seealso: TSSetIFunction(), TSSetRHSJacobian(), SNESComputeJacobianDefaultColor(), SNESComputeJacobianDefault(), TSSetRHSFunction()
1450 
1451 @*/
1452 PetscErrorCode  TSSetIJacobian(TS ts,Mat Amat,Mat Pmat,TSIJacobian f,void *ctx)
1453 {
1454   PetscErrorCode ierr;
1455   SNES           snes;
1456   DM             dm;
1457 
1458   PetscFunctionBegin;
1459   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1460   if (Amat) PetscValidHeaderSpecific(Amat,MAT_CLASSID,2);
1461   if (Pmat) PetscValidHeaderSpecific(Pmat,MAT_CLASSID,3);
1462   if (Amat) PetscCheckSameComm(ts,1,Amat,2);
1463   if (Pmat) PetscCheckSameComm(ts,1,Pmat,3);
1464 
1465   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1466   ierr = DMTSSetIJacobian(dm,f,ctx);CHKERRQ(ierr);
1467 
1468   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1469   ierr = SNESSetJacobian(snes,Amat,Pmat,SNESTSFormJacobian,ts);CHKERRQ(ierr);
1470   PetscFunctionReturn(0);
1471 }
1472 
1473 /*@
1474    TSRHSJacobianSetReuse - restore RHS Jacobian before re-evaluating.  Without this flag, TS will change the sign and
1475    shift the RHS Jacobian for a finite-time-step implicit solve, in which case the user function will need to recompute
1476    the entire Jacobian.  The reuse flag must be set if the evaluation function will assume that the matrix entries have
1477    not been changed by the TS.
1478 
1479    Logically Collective
1480 
1481    Input Arguments:
1482 +  ts - TS context obtained from TSCreate()
1483 -  reuse - PETSC_TRUE if the RHS Jacobian
1484 
1485    Level: intermediate
1486 
1487 .seealso: TSSetRHSJacobian(), TSComputeRHSJacobianConstant()
1488 @*/
1489 PetscErrorCode TSRHSJacobianSetReuse(TS ts,PetscBool reuse)
1490 {
1491   PetscFunctionBegin;
1492   ts->rhsjacobian.reuse = reuse;
1493   PetscFunctionReturn(0);
1494 }
1495 
1496 /*@C
1497    TSSetI2Function - Set the function to compute F(t,U,U_t,U_tt) where F = 0 is the DAE to be solved.
1498 
1499    Logically Collective on TS
1500 
1501    Input Parameters:
1502 +  ts  - the TS context obtained from TSCreate()
1503 .  F   - vector to hold the residual (or NULL to have it created internally)
1504 .  fun - the function evaluation routine
1505 -  ctx - user-defined context for private data for the function evaluation routine (may be NULL)
1506 
1507    Calling sequence of fun:
1508 $  fun(TS ts,PetscReal t,Vec U,Vec U_t,Vec U_tt,Vec F,ctx);
1509 
1510 +  t    - time at step/stage being solved
1511 .  U    - state vector
1512 .  U_t  - time derivative of state vector
1513 .  U_tt - second time derivative of state vector
1514 .  F    - function vector
1515 -  ctx  - [optional] user-defined context for matrix evaluation routine (may be NULL)
1516 
1517    Level: beginner
1518 
1519 .keywords: TS, timestep, set, ODE, DAE, Function
1520 
1521 .seealso: TSSetI2Jacobian()
1522 @*/
1523 PetscErrorCode TSSetI2Function(TS ts,Vec F,TSI2Function fun,void *ctx)
1524 {
1525   DM             dm;
1526   PetscErrorCode ierr;
1527 
1528   PetscFunctionBegin;
1529   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1530   if (F) PetscValidHeaderSpecific(F,VEC_CLASSID,2);
1531   ierr = TSSetIFunction(ts,F,NULL,NULL);CHKERRQ(ierr);
1532   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1533   ierr = DMTSSetI2Function(dm,fun,ctx);CHKERRQ(ierr);
1534   PetscFunctionReturn(0);
1535 }
1536 
1537 /*@C
1538   TSGetI2Function - Returns the vector where the implicit residual is stored and the function/contex to compute it.
1539 
1540   Not Collective
1541 
1542   Input Parameter:
1543 . ts - the TS context
1544 
1545   Output Parameter:
1546 + r - vector to hold residual (or NULL)
1547 . fun - the function to compute residual (or NULL)
1548 - ctx - the function context (or NULL)
1549 
1550   Level: advanced
1551 
1552 .keywords: TS, nonlinear, get, function
1553 
1554 .seealso: TSSetI2Function(), SNESGetFunction()
1555 @*/
1556 PetscErrorCode TSGetI2Function(TS ts,Vec *r,TSI2Function *fun,void **ctx)
1557 {
1558   PetscErrorCode ierr;
1559   SNES           snes;
1560   DM             dm;
1561 
1562   PetscFunctionBegin;
1563   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1564   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1565   ierr = SNESGetFunction(snes,r,NULL,NULL);CHKERRQ(ierr);
1566   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1567   ierr = DMTSGetI2Function(dm,fun,ctx);CHKERRQ(ierr);
1568   PetscFunctionReturn(0);
1569 }
1570 
1571 /*@C
1572    TSSetI2Jacobian - Set the function to compute the matrix dF/dU + v*dF/dU_t  + a*dF/dU_tt
1573         where F(t,U,U_t,U_tt) is the function you provided with TSSetI2Function().
1574 
1575    Logically Collective on TS
1576 
1577    Input Parameters:
1578 +  ts  - the TS context obtained from TSCreate()
1579 .  J   - Jacobian matrix
1580 .  P   - preconditioning matrix for J (may be same as J)
1581 .  jac - the Jacobian evaluation routine
1582 -  ctx - user-defined context for private data for the Jacobian evaluation routine (may be NULL)
1583 
1584    Calling sequence of jac:
1585 $  jac(TS ts,PetscReal t,Vec U,Vec U_t,Vec U_tt,PetscReal v,PetscReal a,Mat J,Mat P,void *ctx);
1586 
1587 +  t    - time at step/stage being solved
1588 .  U    - state vector
1589 .  U_t  - time derivative of state vector
1590 .  U_tt - second time derivative of state vector
1591 .  v    - shift for U_t
1592 .  a    - shift for U_tt
1593 .  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
1594 .  P    - preconditioning matrix for J, may be same as J
1595 -  ctx  - [optional] user-defined context for matrix evaluation routine
1596 
1597    Notes:
1598    The matrices J and P are exactly the matrices that are used by SNES for the nonlinear solve.
1599 
1600    The matrix dF/dU + v*dF/dU_t + a*dF/dU_tt you provide turns out to be
1601    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.
1602    The time integrator internally approximates U_t by W+v*U and U_tt by W'+a*U  where the positive "shift"
1603    parameters 'v' and 'a' and vectors W, W' depend on the integration method, step size, and past states.
1604 
1605    Level: beginner
1606 
1607 .keywords: TS, timestep, set, ODE, DAE, Jacobian
1608 
1609 .seealso: TSSetI2Function()
1610 @*/
1611 PetscErrorCode TSSetI2Jacobian(TS ts,Mat J,Mat P,TSI2Jacobian jac,void *ctx)
1612 {
1613   DM             dm;
1614   PetscErrorCode ierr;
1615 
1616   PetscFunctionBegin;
1617   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1618   if (J) PetscValidHeaderSpecific(J,MAT_CLASSID,2);
1619   if (P) PetscValidHeaderSpecific(P,MAT_CLASSID,3);
1620   ierr = TSSetIJacobian(ts,J,P,NULL,NULL);CHKERRQ(ierr);
1621   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1622   ierr = DMTSSetI2Jacobian(dm,jac,ctx);CHKERRQ(ierr);
1623   PetscFunctionReturn(0);
1624 }
1625 
1626 /*@C
1627   TSGetI2Jacobian - Returns the implicit Jacobian at the present timestep.
1628 
1629   Not Collective, but parallel objects are returned if TS is parallel
1630 
1631   Input Parameter:
1632 . ts  - The TS context obtained from TSCreate()
1633 
1634   Output Parameters:
1635 + J  - The (approximate) Jacobian of F(t,U,U_t,U_tt)
1636 . P - The matrix from which the preconditioner is constructed, often the same as J
1637 . jac - The function to compute the Jacobian matrices
1638 - ctx - User-defined context for Jacobian evaluation routine
1639 
1640   Notes:
1641     You can pass in NULL for any return argument you do not need.
1642 
1643   Level: advanced
1644 
1645 .seealso: TSGetTimeStep(), TSGetMatrices(), TSGetTime(), TSGetStepNumber()
1646 
1647 .keywords: TS, timestep, get, matrix, Jacobian
1648 @*/
1649 PetscErrorCode  TSGetI2Jacobian(TS ts,Mat *J,Mat *P,TSI2Jacobian *jac,void **ctx)
1650 {
1651   PetscErrorCode ierr;
1652   SNES           snes;
1653   DM             dm;
1654 
1655   PetscFunctionBegin;
1656   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1657   ierr = SNESSetUpMatrices(snes);CHKERRQ(ierr);
1658   ierr = SNESGetJacobian(snes,J,P,NULL,NULL);CHKERRQ(ierr);
1659   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1660   ierr = DMTSGetI2Jacobian(dm,jac,ctx);CHKERRQ(ierr);
1661   PetscFunctionReturn(0);
1662 }
1663 
1664 /*@
1665   TSComputeI2Function - Evaluates the DAE residual written in implicit form F(t,U,U_t,U_tt) = 0
1666 
1667   Collective on TS and Vec
1668 
1669   Input Parameters:
1670 + ts - the TS context
1671 . t - current time
1672 . U - state vector
1673 . V - time derivative of state vector (U_t)
1674 - A - second time derivative of state vector (U_tt)
1675 
1676   Output Parameter:
1677 . F - the residual vector
1678 
1679   Note:
1680   Most users should not need to explicitly call this routine, as it
1681   is used internally within the nonlinear solvers.
1682 
1683   Level: developer
1684 
1685 .keywords: TS, compute, function, vector
1686 
1687 .seealso: TSSetI2Function()
1688 @*/
1689 PetscErrorCode TSComputeI2Function(TS ts,PetscReal t,Vec U,Vec V,Vec A,Vec F)
1690 {
1691   DM             dm;
1692   TSI2Function   I2Function;
1693   void           *ctx;
1694   TSRHSFunction  rhsfunction;
1695   PetscErrorCode ierr;
1696 
1697   PetscFunctionBegin;
1698   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1699   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
1700   PetscValidHeaderSpecific(V,VEC_CLASSID,4);
1701   PetscValidHeaderSpecific(A,VEC_CLASSID,5);
1702   PetscValidHeaderSpecific(F,VEC_CLASSID,6);
1703 
1704   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1705   ierr = DMTSGetI2Function(dm,&I2Function,&ctx);CHKERRQ(ierr);
1706   ierr = DMTSGetRHSFunction(dm,&rhsfunction,NULL);CHKERRQ(ierr);
1707 
1708   if (!I2Function) {
1709     ierr = TSComputeIFunction(ts,t,U,A,F,PETSC_FALSE);CHKERRQ(ierr);
1710     PetscFunctionReturn(0);
1711   }
1712 
1713   ierr = PetscLogEventBegin(TS_FunctionEval,ts,U,V,F);CHKERRQ(ierr);
1714 
1715   PetscStackPush("TS user implicit function");
1716   ierr = I2Function(ts,t,U,V,A,F,ctx);CHKERRQ(ierr);
1717   PetscStackPop;
1718 
1719   if (rhsfunction) {
1720     Vec Frhs;
1721     ierr = TSGetRHSVec_Private(ts,&Frhs);CHKERRQ(ierr);
1722     ierr = TSComputeRHSFunction(ts,t,U,Frhs);CHKERRQ(ierr);
1723     ierr = VecAXPY(F,-1,Frhs);CHKERRQ(ierr);
1724   }
1725 
1726   ierr = PetscLogEventEnd(TS_FunctionEval,ts,U,V,F);CHKERRQ(ierr);
1727   PetscFunctionReturn(0);
1728 }
1729 
1730 /*@
1731   TSComputeI2Jacobian - Evaluates the Jacobian of the DAE
1732 
1733   Collective on TS and Vec
1734 
1735   Input Parameters:
1736 + ts - the TS context
1737 . t - current timestep
1738 . U - state vector
1739 . V - time derivative of state vector
1740 . A - second time derivative of state vector
1741 . shiftV - shift to apply, see note below
1742 - shiftA - shift to apply, see note below
1743 
1744   Output Parameters:
1745 + J - Jacobian matrix
1746 - P - optional preconditioning matrix
1747 
1748   Notes:
1749   If F(t,U,V,A)=0 is the DAE, the required Jacobian is
1750 
1751   dF/dU + shiftV*dF/dV + shiftA*dF/dA
1752 
1753   Most users should not need to explicitly call this routine, as it
1754   is used internally within the nonlinear solvers.
1755 
1756   Level: developer
1757 
1758 .keywords: TS, compute, Jacobian, matrix
1759 
1760 .seealso:  TSSetI2Jacobian()
1761 @*/
1762 PetscErrorCode TSComputeI2Jacobian(TS ts,PetscReal t,Vec U,Vec V,Vec A,PetscReal shiftV,PetscReal shiftA,Mat J,Mat P)
1763 {
1764   DM             dm;
1765   TSI2Jacobian   I2Jacobian;
1766   void           *ctx;
1767   TSRHSJacobian  rhsjacobian;
1768   PetscErrorCode ierr;
1769 
1770   PetscFunctionBegin;
1771   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1772   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
1773   PetscValidHeaderSpecific(V,VEC_CLASSID,4);
1774   PetscValidHeaderSpecific(A,VEC_CLASSID,5);
1775   PetscValidHeaderSpecific(J,MAT_CLASSID,8);
1776   PetscValidHeaderSpecific(P,MAT_CLASSID,9);
1777 
1778   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1779   ierr = DMTSGetI2Jacobian(dm,&I2Jacobian,&ctx);CHKERRQ(ierr);
1780   ierr = DMTSGetRHSJacobian(dm,&rhsjacobian,NULL);CHKERRQ(ierr);
1781 
1782   if (!I2Jacobian) {
1783     ierr = TSComputeIJacobian(ts,t,U,A,shiftA,J,P,PETSC_FALSE);CHKERRQ(ierr);
1784     PetscFunctionReturn(0);
1785   }
1786 
1787   ierr = PetscLogEventBegin(TS_JacobianEval,ts,U,J,P);CHKERRQ(ierr);
1788 
1789   PetscStackPush("TS user implicit Jacobian");
1790   ierr = I2Jacobian(ts,t,U,V,A,shiftV,shiftA,J,P,ctx);CHKERRQ(ierr);
1791   PetscStackPop;
1792 
1793   if (rhsjacobian) {
1794     Mat Jrhs,Prhs; MatStructure axpy = DIFFERENT_NONZERO_PATTERN;
1795     ierr = TSGetRHSMats_Private(ts,&Jrhs,&Prhs);CHKERRQ(ierr);
1796     ierr = TSComputeRHSJacobian(ts,t,U,Jrhs,Prhs);CHKERRQ(ierr);
1797     ierr = MatAXPY(J,-1,Jrhs,axpy);CHKERRQ(ierr);
1798     if (P != J) {ierr = MatAXPY(P,-1,Prhs,axpy);CHKERRQ(ierr);}
1799   }
1800 
1801   ierr = PetscLogEventEnd(TS_JacobianEval,ts,U,J,P);CHKERRQ(ierr);
1802   PetscFunctionReturn(0);
1803 }
1804 
1805 /*@
1806    TS2SetSolution - Sets the initial solution and time derivative vectors
1807    for use by the TS routines handling second order equations.
1808 
1809    Logically Collective on TS and Vec
1810 
1811    Input Parameters:
1812 +  ts - the TS context obtained from TSCreate()
1813 .  u - the solution vector
1814 -  v - the time derivative vector
1815 
1816    Level: beginner
1817 
1818 .keywords: TS, timestep, set, solution, initial conditions
1819 @*/
1820 PetscErrorCode  TS2SetSolution(TS ts,Vec u,Vec v)
1821 {
1822   PetscErrorCode ierr;
1823 
1824   PetscFunctionBegin;
1825   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1826   PetscValidHeaderSpecific(u,VEC_CLASSID,2);
1827   PetscValidHeaderSpecific(v,VEC_CLASSID,3);
1828   ierr = TSSetSolution(ts,u);CHKERRQ(ierr);
1829   ierr = PetscObjectReference((PetscObject)v);CHKERRQ(ierr);
1830   ierr = VecDestroy(&ts->vec_dot);CHKERRQ(ierr);
1831   ts->vec_dot = v;
1832   PetscFunctionReturn(0);
1833 }
1834 
1835 /*@
1836    TS2GetSolution - Returns the solution and time derivative at the present timestep
1837    for second order equations. It is valid to call this routine inside the function
1838    that you are evaluating in order to move to the new timestep. This vector not
1839    changed until the solution at the next timestep has been calculated.
1840 
1841    Not Collective, but Vec returned is parallel if TS is parallel
1842 
1843    Input Parameter:
1844 .  ts - the TS context obtained from TSCreate()
1845 
1846    Output Parameter:
1847 +  u - the vector containing the solution
1848 -  v - the vector containing the time derivative
1849 
1850    Level: intermediate
1851 
1852 .seealso: TS2SetSolution(), TSGetTimeStep(), TSGetTime()
1853 
1854 .keywords: TS, timestep, get, solution
1855 @*/
1856 PetscErrorCode  TS2GetSolution(TS ts,Vec *u,Vec *v)
1857 {
1858   PetscFunctionBegin;
1859   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1860   if (u) PetscValidPointer(u,2);
1861   if (v) PetscValidPointer(v,3);
1862   if (u) *u = ts->vec_sol;
1863   if (v) *v = ts->vec_dot;
1864   PetscFunctionReturn(0);
1865 }
1866 
1867 /*@C
1868   TSLoad - Loads a KSP that has been stored in binary  with KSPView().
1869 
1870   Collective on PetscViewer
1871 
1872   Input Parameters:
1873 + newdm - the newly loaded TS, this needs to have been created with TSCreate() or
1874            some related function before a call to TSLoad().
1875 - viewer - binary file viewer, obtained from PetscViewerBinaryOpen()
1876 
1877    Level: intermediate
1878 
1879   Notes:
1880    The type is determined by the data in the file, any type set into the TS before this call is ignored.
1881 
1882   Notes for advanced users:
1883   Most users should not need to know the details of the binary storage
1884   format, since TSLoad() and TSView() completely hide these details.
1885   But for anyone who's interested, the standard binary matrix storage
1886   format is
1887 .vb
1888      has not yet been determined
1889 .ve
1890 
1891 .seealso: PetscViewerBinaryOpen(), TSView(), MatLoad(), VecLoad()
1892 @*/
1893 PetscErrorCode  TSLoad(TS ts, PetscViewer viewer)
1894 {
1895   PetscErrorCode ierr;
1896   PetscBool      isbinary;
1897   PetscInt       classid;
1898   char           type[256];
1899   DMTS           sdm;
1900   DM             dm;
1901 
1902   PetscFunctionBegin;
1903   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1904   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2);
1905   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1906   if (!isbinary) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid viewer; open viewer with PetscViewerBinaryOpen()");
1907 
1908   ierr = PetscViewerBinaryRead(viewer,&classid,1,NULL,PETSC_INT);CHKERRQ(ierr);
1909   if (classid != TS_FILE_CLASSID) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Not TS next in file");
1910   ierr = PetscViewerBinaryRead(viewer,type,256,NULL,PETSC_CHAR);CHKERRQ(ierr);
1911   ierr = TSSetType(ts, type);CHKERRQ(ierr);
1912   if (ts->ops->load) {
1913     ierr = (*ts->ops->load)(ts,viewer);CHKERRQ(ierr);
1914   }
1915   ierr = DMCreate(PetscObjectComm((PetscObject)ts),&dm);CHKERRQ(ierr);
1916   ierr = DMLoad(dm,viewer);CHKERRQ(ierr);
1917   ierr = TSSetDM(ts,dm);CHKERRQ(ierr);
1918   ierr = DMCreateGlobalVector(ts->dm,&ts->vec_sol);CHKERRQ(ierr);
1919   ierr = VecLoad(ts->vec_sol,viewer);CHKERRQ(ierr);
1920   ierr = DMGetDMTS(ts->dm,&sdm);CHKERRQ(ierr);
1921   ierr = DMTSLoad(sdm,viewer);CHKERRQ(ierr);
1922   PetscFunctionReturn(0);
1923 }
1924 
1925 #include <petscdraw.h>
1926 #if defined(PETSC_HAVE_SAWS)
1927 #include <petscviewersaws.h>
1928 #endif
1929 /*@C
1930     TSView - Prints the TS data structure.
1931 
1932     Collective on TS
1933 
1934     Input Parameters:
1935 +   ts - the TS context obtained from TSCreate()
1936 -   viewer - visualization context
1937 
1938     Options Database Key:
1939 .   -ts_view - calls TSView() at end of TSStep()
1940 
1941     Notes:
1942     The available visualization contexts include
1943 +     PETSC_VIEWER_STDOUT_SELF - standard output (default)
1944 -     PETSC_VIEWER_STDOUT_WORLD - synchronized standard
1945          output where only the first processor opens
1946          the file.  All other processors send their
1947          data to the first processor to print.
1948 
1949     The user can open an alternative visualization context with
1950     PetscViewerASCIIOpen() - output to a specified file.
1951 
1952     Level: beginner
1953 
1954 .keywords: TS, timestep, view
1955 
1956 .seealso: PetscViewerASCIIOpen()
1957 @*/
1958 PetscErrorCode  TSView(TS ts,PetscViewer viewer)
1959 {
1960   PetscErrorCode ierr;
1961   TSType         type;
1962   PetscBool      iascii,isstring,isundials,isbinary,isdraw;
1963   DMTS           sdm;
1964 #if defined(PETSC_HAVE_SAWS)
1965   PetscBool      issaws;
1966 #endif
1967 
1968   PetscFunctionBegin;
1969   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1970   if (!viewer) {
1971     ierr = PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)ts),&viewer);CHKERRQ(ierr);
1972   }
1973   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2);
1974   PetscCheckSameComm(ts,1,viewer,2);
1975 
1976   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1977   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);CHKERRQ(ierr);
1978   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1979   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1980 #if defined(PETSC_HAVE_SAWS)
1981   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSAWS,&issaws);CHKERRQ(ierr);
1982 #endif
1983   if (iascii) {
1984     ierr = PetscObjectPrintClassNamePrefixType((PetscObject)ts,viewer);CHKERRQ(ierr);
1985     if (ts->ops->view) {
1986       ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
1987       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
1988       ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
1989     }
1990     if (ts->max_steps < PETSC_MAX_INT) {
1991       ierr = PetscViewerASCIIPrintf(viewer,"  maximum steps=%D\n",ts->max_steps);CHKERRQ(ierr);
1992     }
1993     if (ts->max_time < PETSC_MAX_REAL) {
1994       ierr = PetscViewerASCIIPrintf(viewer,"  maximum time=%g\n",(double)ts->max_time);CHKERRQ(ierr);
1995     }
1996     if (ts->usessnes) {
1997       PetscBool lin;
1998       if (ts->problem_type == TS_NONLINEAR) {
1999         ierr = PetscViewerASCIIPrintf(viewer,"  total number of nonlinear solver iterations=%D\n",ts->snes_its);CHKERRQ(ierr);
2000       }
2001       ierr = PetscViewerASCIIPrintf(viewer,"  total number of linear solver iterations=%D\n",ts->ksp_its);CHKERRQ(ierr);
2002       ierr = PetscObjectTypeCompareAny((PetscObject)ts->snes,&lin,SNESKSPONLY,SNESKSPTRANSPOSEONLY,"");CHKERRQ(ierr);
2003       ierr = PetscViewerASCIIPrintf(viewer,"  total number of %slinear solve failures=%D\n",lin ? "" : "non",ts->num_snes_failures);CHKERRQ(ierr);
2004     }
2005     ierr = PetscViewerASCIIPrintf(viewer,"  total number of rejected steps=%D\n",ts->reject);CHKERRQ(ierr);
2006     if (ts->vrtol) {
2007       ierr = PetscViewerASCIIPrintf(viewer,"  using vector of relative error tolerances, ");CHKERRQ(ierr);
2008     } else {
2009       ierr = PetscViewerASCIIPrintf(viewer,"  using relative error tolerance of %g, ",(double)ts->rtol);CHKERRQ(ierr);
2010     }
2011     if (ts->vatol) {
2012       ierr = PetscViewerASCIIPrintf(viewer,"  using vector of absolute error tolerances\n");CHKERRQ(ierr);
2013     } else {
2014       ierr = PetscViewerASCIIPrintf(viewer,"  using absolute error tolerance of %g\n",(double)ts->atol);CHKERRQ(ierr);
2015     }
2016     ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
2017     ierr = TSAdaptView(ts->adapt,viewer);CHKERRQ(ierr);
2018     ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
2019     if (ts->snes && ts->usessnes)  {
2020       ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
2021       ierr = SNESView(ts->snes,viewer);CHKERRQ(ierr);
2022       ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
2023     }
2024     ierr = DMGetDMTS(ts->dm,&sdm);CHKERRQ(ierr);
2025     ierr = DMTSView(sdm,viewer);CHKERRQ(ierr);
2026   } else if (isstring) {
2027     ierr = TSGetType(ts,&type);CHKERRQ(ierr);
2028     ierr = PetscViewerStringSPrintf(viewer," %-7.7s",type);CHKERRQ(ierr);
2029   } else if (isbinary) {
2030     PetscInt    classid = TS_FILE_CLASSID;
2031     MPI_Comm    comm;
2032     PetscMPIInt rank;
2033     char        type[256];
2034 
2035     ierr = PetscObjectGetComm((PetscObject)ts,&comm);CHKERRQ(ierr);
2036     ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
2037     if (!rank) {
2038       ierr = PetscViewerBinaryWrite(viewer,&classid,1,PETSC_INT,PETSC_FALSE);CHKERRQ(ierr);
2039       ierr = PetscStrncpy(type,((PetscObject)ts)->type_name,256);CHKERRQ(ierr);
2040       ierr = PetscViewerBinaryWrite(viewer,type,256,PETSC_CHAR,PETSC_FALSE);CHKERRQ(ierr);
2041     }
2042     if (ts->ops->view) {
2043       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
2044     }
2045     if (ts->adapt) {ierr = TSAdaptView(ts->adapt,viewer);CHKERRQ(ierr);}
2046     ierr = DMView(ts->dm,viewer);CHKERRQ(ierr);
2047     ierr = VecView(ts->vec_sol,viewer);CHKERRQ(ierr);
2048     ierr = DMGetDMTS(ts->dm,&sdm);CHKERRQ(ierr);
2049     ierr = DMTSView(sdm,viewer);CHKERRQ(ierr);
2050   } else if (isdraw) {
2051     PetscDraw draw;
2052     char      str[36];
2053     PetscReal x,y,bottom,h;
2054 
2055     ierr   = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
2056     ierr   = PetscDrawGetCurrentPoint(draw,&x,&y);CHKERRQ(ierr);
2057     ierr   = PetscStrcpy(str,"TS: ");CHKERRQ(ierr);
2058     ierr   = PetscStrcat(str,((PetscObject)ts)->type_name);CHKERRQ(ierr);
2059     ierr   = PetscDrawStringBoxed(draw,x,y,PETSC_DRAW_BLACK,PETSC_DRAW_BLACK,str,NULL,&h);CHKERRQ(ierr);
2060     bottom = y - h;
2061     ierr   = PetscDrawPushCurrentPoint(draw,x,bottom);CHKERRQ(ierr);
2062     if (ts->ops->view) {
2063       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
2064     }
2065     if (ts->adapt) {ierr = TSAdaptView(ts->adapt,viewer);CHKERRQ(ierr);}
2066     if (ts->snes)  {ierr = SNESView(ts->snes,viewer);CHKERRQ(ierr);}
2067     ierr = PetscDrawPopCurrentPoint(draw);CHKERRQ(ierr);
2068 #if defined(PETSC_HAVE_SAWS)
2069   } else if (issaws) {
2070     PetscMPIInt rank;
2071     const char  *name;
2072 
2073     ierr = PetscObjectGetName((PetscObject)ts,&name);CHKERRQ(ierr);
2074     ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
2075     if (!((PetscObject)ts)->amsmem && !rank) {
2076       char       dir[1024];
2077 
2078       ierr = PetscObjectViewSAWs((PetscObject)ts,viewer);CHKERRQ(ierr);
2079       ierr = PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/time_step",name);CHKERRQ(ierr);
2080       PetscStackCallSAWs(SAWs_Register,(dir,&ts->steps,1,SAWs_READ,SAWs_INT));
2081       ierr = PetscSNPrintf(dir,1024,"/PETSc/Objects/%s/time",name);CHKERRQ(ierr);
2082       PetscStackCallSAWs(SAWs_Register,(dir,&ts->ptime,1,SAWs_READ,SAWs_DOUBLE));
2083     }
2084     if (ts->ops->view) {
2085       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
2086     }
2087 #endif
2088   }
2089 
2090   ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
2091   ierr = PetscObjectTypeCompare((PetscObject)ts,TSSUNDIALS,&isundials);CHKERRQ(ierr);
2092   ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
2093   PetscFunctionReturn(0);
2094 }
2095 
2096 /*@
2097    TSSetApplicationContext - Sets an optional user-defined context for
2098    the timesteppers.
2099 
2100    Logically Collective on TS
2101 
2102    Input Parameters:
2103 +  ts - the TS context obtained from TSCreate()
2104 -  usrP - optional user context
2105 
2106    Fortran Notes:
2107     To use this from Fortran you must write a Fortran interface definition for this
2108     function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
2109 
2110    Level: intermediate
2111 
2112 .keywords: TS, timestep, set, application, context
2113 
2114 .seealso: TSGetApplicationContext()
2115 @*/
2116 PetscErrorCode  TSSetApplicationContext(TS ts,void *usrP)
2117 {
2118   PetscFunctionBegin;
2119   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2120   ts->user = usrP;
2121   PetscFunctionReturn(0);
2122 }
2123 
2124 /*@
2125     TSGetApplicationContext - Gets the user-defined context for the
2126     timestepper.
2127 
2128     Not Collective
2129 
2130     Input Parameter:
2131 .   ts - the TS context obtained from TSCreate()
2132 
2133     Output Parameter:
2134 .   usrP - user context
2135 
2136    Fortran Notes:
2137     To use this from Fortran you must write a Fortran interface definition for this
2138     function that tells Fortran the Fortran derived data type that you are passing in as the ctx argument.
2139 
2140     Level: intermediate
2141 
2142 .keywords: TS, timestep, get, application, context
2143 
2144 .seealso: TSSetApplicationContext()
2145 @*/
2146 PetscErrorCode  TSGetApplicationContext(TS ts,void *usrP)
2147 {
2148   PetscFunctionBegin;
2149   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2150   *(void**)usrP = ts->user;
2151   PetscFunctionReturn(0);
2152 }
2153 
2154 /*@
2155    TSGetStepNumber - Gets the number of steps completed.
2156 
2157    Not Collective
2158 
2159    Input Parameter:
2160 .  ts - the TS context obtained from TSCreate()
2161 
2162    Output Parameter:
2163 .  steps - number of steps completed so far
2164 
2165    Level: intermediate
2166 
2167 .keywords: TS, timestep, get, iteration, number
2168 .seealso: TSGetTime(), TSGetTimeStep(), TSSetPreStep(), TSSetPreStage(), TSSetPostStage(), TSSetPostStep()
2169 @*/
2170 PetscErrorCode TSGetStepNumber(TS ts,PetscInt *steps)
2171 {
2172   PetscFunctionBegin;
2173   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2174   PetscValidIntPointer(steps,2);
2175   *steps = ts->steps;
2176   PetscFunctionReturn(0);
2177 }
2178 
2179 /*@
2180    TSSetStepNumber - Sets the number of steps completed.
2181 
2182    Logically Collective on TS
2183 
2184    Input Parameters:
2185 +  ts - the TS context
2186 -  steps - number of steps completed so far
2187 
2188    Notes:
2189    For most uses of the TS solvers the user need not explicitly call
2190    TSSetStepNumber(), as the step counter is appropriately updated in
2191    TSSolve()/TSStep()/TSRollBack(). Power users may call this routine to
2192    reinitialize timestepping by setting the step counter to zero (and time
2193    to the initial time) to solve a similar problem with different initial
2194    conditions or parameters. Other possible use case is to continue
2195    timestepping from a previously interrupted run in such a way that TS
2196    monitors will be called with a initial nonzero step counter.
2197 
2198    Level: advanced
2199 
2200 .keywords: TS, timestep, set, iteration, number
2201 .seealso: TSGetStepNumber(), TSSetTime(), TSSetTimeStep(), TSSetSolution()
2202 @*/
2203 PetscErrorCode TSSetStepNumber(TS ts,PetscInt steps)
2204 {
2205   PetscFunctionBegin;
2206   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2207   PetscValidLogicalCollectiveInt(ts,steps,2);
2208   if (steps < 0) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_OUTOFRANGE,"Step number must be non-negative");
2209   ts->steps = steps;
2210   PetscFunctionReturn(0);
2211 }
2212 
2213 /*@
2214    TSSetTimeStep - Allows one to reset the timestep at any time,
2215    useful for simple pseudo-timestepping codes.
2216 
2217    Logically Collective on TS
2218 
2219    Input Parameters:
2220 +  ts - the TS context obtained from TSCreate()
2221 -  time_step - the size of the timestep
2222 
2223    Level: intermediate
2224 
2225 .seealso: TSGetTimeStep(), TSSetTime()
2226 
2227 .keywords: TS, set, timestep
2228 @*/
2229 PetscErrorCode  TSSetTimeStep(TS ts,PetscReal time_step)
2230 {
2231   PetscFunctionBegin;
2232   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2233   PetscValidLogicalCollectiveReal(ts,time_step,2);
2234   ts->time_step = time_step;
2235   PetscFunctionReturn(0);
2236 }
2237 
2238 /*@
2239    TSSetExactFinalTime - Determines whether to adapt the final time step to
2240      match the exact final time, interpolate solution to the exact final time,
2241      or just return at the final time TS computed.
2242 
2243   Logically Collective on TS
2244 
2245    Input Parameter:
2246 +   ts - the time-step context
2247 -   eftopt - exact final time option
2248 
2249 $  TS_EXACTFINALTIME_STEPOVER    - Don't do anything if final time is exceeded
2250 $  TS_EXACTFINALTIME_INTERPOLATE - Interpolate back to final time
2251 $  TS_EXACTFINALTIME_MATCHSTEP - Adapt final time step to match the final time
2252 
2253    Options Database:
2254 .   -ts_exact_final_time <stepover,interpolate,matchstep> - select the final step at runtime
2255 
2256    Warning: If you use the option TS_EXACTFINALTIME_STEPOVER the solution may be at a very different time
2257     then the final time you selected.
2258 
2259    Level: beginner
2260 
2261 .seealso: TSExactFinalTimeOption, TSGetExactFinalTime()
2262 @*/
2263 PetscErrorCode TSSetExactFinalTime(TS ts,TSExactFinalTimeOption eftopt)
2264 {
2265   PetscFunctionBegin;
2266   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2267   PetscValidLogicalCollectiveEnum(ts,eftopt,2);
2268   ts->exact_final_time = eftopt;
2269   PetscFunctionReturn(0);
2270 }
2271 
2272 /*@
2273    TSGetExactFinalTime - Gets the exact final time option.
2274 
2275    Not Collective
2276 
2277    Input Parameter:
2278 .  ts - the TS context
2279 
2280    Output Parameter:
2281 .  eftopt - exact final time option
2282 
2283    Level: beginner
2284 
2285 .seealso: TSExactFinalTimeOption, TSSetExactFinalTime()
2286 @*/
2287 PetscErrorCode TSGetExactFinalTime(TS ts,TSExactFinalTimeOption *eftopt)
2288 {
2289   PetscFunctionBegin;
2290   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2291   PetscValidPointer(eftopt,2);
2292   *eftopt = ts->exact_final_time;
2293   PetscFunctionReturn(0);
2294 }
2295 
2296 /*@
2297    TSGetTimeStep - Gets the current timestep size.
2298 
2299    Not Collective
2300 
2301    Input Parameter:
2302 .  ts - the TS context obtained from TSCreate()
2303 
2304    Output Parameter:
2305 .  dt - the current timestep size
2306 
2307    Level: intermediate
2308 
2309 .seealso: TSSetTimeStep(), TSGetTime()
2310 
2311 .keywords: TS, get, timestep
2312 @*/
2313 PetscErrorCode  TSGetTimeStep(TS ts,PetscReal *dt)
2314 {
2315   PetscFunctionBegin;
2316   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2317   PetscValidRealPointer(dt,2);
2318   *dt = ts->time_step;
2319   PetscFunctionReturn(0);
2320 }
2321 
2322 /*@
2323    TSGetSolution - Returns the solution at the present timestep. It
2324    is valid to call this routine inside the function that you are evaluating
2325    in order to move to the new timestep. This vector not changed until
2326    the solution at the next timestep has been calculated.
2327 
2328    Not Collective, but Vec returned is parallel if TS is parallel
2329 
2330    Input Parameter:
2331 .  ts - the TS context obtained from TSCreate()
2332 
2333    Output Parameter:
2334 .  v - the vector containing the solution
2335 
2336    Note: If you used TSSetExactFinalTime(ts,TS_EXACTFINALTIME_MATCHSTEP); this does not return the solution at the requested
2337    final time. It returns the solution at the next timestep.
2338 
2339    Level: intermediate
2340 
2341 .seealso: TSGetTimeStep(), TSGetTime(), TSGetSolveTime(), TSGetSolutionComponents(), TSSetSolutionFunction()
2342 
2343 .keywords: TS, timestep, get, solution
2344 @*/
2345 PetscErrorCode  TSGetSolution(TS ts,Vec *v)
2346 {
2347   PetscFunctionBegin;
2348   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2349   PetscValidPointer(v,2);
2350   *v = ts->vec_sol;
2351   PetscFunctionReturn(0);
2352 }
2353 
2354 /*@
2355    TSGetSolutionComponents - Returns any solution components at the present
2356    timestep, if available for the time integration method being used.
2357    Solution components are quantities that share the same size and
2358    structure as the solution vector.
2359 
2360    Not Collective, but Vec returned is parallel if TS is parallel
2361 
2362    Parameters :
2363 .  ts - the TS context obtained from TSCreate() (input parameter).
2364 .  n - If v is PETSC_NULL, then the number of solution components is
2365        returned through n, else the n-th solution component is
2366        returned in v.
2367 .  v - the vector containing the n-th solution component
2368        (may be PETSC_NULL to use this function to find out
2369         the number of solutions components).
2370 
2371    Level: advanced
2372 
2373 .seealso: TSGetSolution()
2374 
2375 .keywords: TS, timestep, get, solution
2376 @*/
2377 PetscErrorCode  TSGetSolutionComponents(TS ts,PetscInt *n,Vec *v)
2378 {
2379   PetscErrorCode ierr;
2380 
2381   PetscFunctionBegin;
2382   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2383   if (!ts->ops->getsolutioncomponents) *n = 0;
2384   else {
2385     ierr = (*ts->ops->getsolutioncomponents)(ts,n,v);CHKERRQ(ierr);
2386   }
2387   PetscFunctionReturn(0);
2388 }
2389 
2390 /*@
2391    TSGetAuxSolution - Returns an auxiliary solution at the present
2392    timestep, if available for the time integration method being used.
2393 
2394    Not Collective, but Vec returned is parallel if TS is parallel
2395 
2396    Parameters :
2397 .  ts - the TS context obtained from TSCreate() (input parameter).
2398 .  v - the vector containing the auxiliary solution
2399 
2400    Level: intermediate
2401 
2402 .seealso: TSGetSolution()
2403 
2404 .keywords: TS, timestep, get, solution
2405 @*/
2406 PetscErrorCode  TSGetAuxSolution(TS ts,Vec *v)
2407 {
2408   PetscErrorCode ierr;
2409 
2410   PetscFunctionBegin;
2411   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2412   if (ts->ops->getauxsolution) {
2413     ierr = (*ts->ops->getauxsolution)(ts,v);CHKERRQ(ierr);
2414   } else {
2415     ierr = VecZeroEntries(*v); CHKERRQ(ierr);
2416   }
2417   PetscFunctionReturn(0);
2418 }
2419 
2420 /*@
2421    TSGetTimeError - Returns the estimated error vector, if the chosen
2422    TSType has an error estimation functionality.
2423 
2424    Not Collective, but Vec returned is parallel if TS is parallel
2425 
2426    Note: MUST call after TSSetUp()
2427 
2428    Parameters :
2429 .  ts - the TS context obtained from TSCreate() (input parameter).
2430 .  n - current estimate (n=0) or previous one (n=-1)
2431 .  v - the vector containing the error (same size as the solution).
2432 
2433    Level: intermediate
2434 
2435 .seealso: TSGetSolution(), TSSetTimeError()
2436 
2437 .keywords: TS, timestep, get, error
2438 @*/
2439 PetscErrorCode  TSGetTimeError(TS ts,PetscInt n,Vec *v)
2440 {
2441   PetscErrorCode ierr;
2442 
2443   PetscFunctionBegin;
2444   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2445   if (ts->ops->gettimeerror) {
2446     ierr = (*ts->ops->gettimeerror)(ts,n,v);CHKERRQ(ierr);
2447   } else {
2448     ierr = VecZeroEntries(*v);CHKERRQ(ierr);
2449   }
2450   PetscFunctionReturn(0);
2451 }
2452 
2453 /*@
2454    TSSetTimeError - Sets the estimated error vector, if the chosen
2455    TSType has an error estimation functionality. This can be used
2456    to restart such a time integrator with a given error vector.
2457 
2458    Not Collective, but Vec returned is parallel if TS is parallel
2459 
2460    Parameters :
2461 .  ts - the TS context obtained from TSCreate() (input parameter).
2462 .  v - the vector containing the error (same size as the solution).
2463 
2464    Level: intermediate
2465 
2466 .seealso: TSSetSolution(), TSGetTimeError)
2467 
2468 .keywords: TS, timestep, get, error
2469 @*/
2470 PetscErrorCode  TSSetTimeError(TS ts,Vec v)
2471 {
2472   PetscErrorCode ierr;
2473 
2474   PetscFunctionBegin;
2475   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2476   if (!ts->setupcalled) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call TSSetUp() first");
2477   if (ts->ops->settimeerror) {
2478     ierr = (*ts->ops->settimeerror)(ts,v);CHKERRQ(ierr);
2479   }
2480   PetscFunctionReturn(0);
2481 }
2482 
2483 /* ----- Routines to initialize and destroy a timestepper ---- */
2484 /*@
2485   TSSetProblemType - Sets the type of problem to be solved.
2486 
2487   Not collective
2488 
2489   Input Parameters:
2490 + ts   - The TS
2491 - type - One of TS_LINEAR, TS_NONLINEAR where these types refer to problems of the forms
2492 .vb
2493          U_t - A U = 0      (linear)
2494          U_t - A(t) U = 0   (linear)
2495          F(t,U,U_t) = 0     (nonlinear)
2496 .ve
2497 
2498    Level: beginner
2499 
2500 .keywords: TS, problem type
2501 .seealso: TSSetUp(), TSProblemType, TS
2502 @*/
2503 PetscErrorCode  TSSetProblemType(TS ts, TSProblemType type)
2504 {
2505   PetscErrorCode ierr;
2506 
2507   PetscFunctionBegin;
2508   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2509   ts->problem_type = type;
2510   if (type == TS_LINEAR) {
2511     SNES snes;
2512     ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2513     ierr = SNESSetType(snes,SNESKSPONLY);CHKERRQ(ierr);
2514   }
2515   PetscFunctionReturn(0);
2516 }
2517 
2518 /*@C
2519   TSGetProblemType - Gets the type of problem to be solved.
2520 
2521   Not collective
2522 
2523   Input Parameter:
2524 . ts   - The TS
2525 
2526   Output Parameter:
2527 . type - One of TS_LINEAR, TS_NONLINEAR where these types refer to problems of the forms
2528 .vb
2529          M U_t = A U
2530          M(t) U_t = A(t) U
2531          F(t,U,U_t)
2532 .ve
2533 
2534    Level: beginner
2535 
2536 .keywords: TS, problem type
2537 .seealso: TSSetUp(), TSProblemType, TS
2538 @*/
2539 PetscErrorCode  TSGetProblemType(TS ts, TSProblemType *type)
2540 {
2541   PetscFunctionBegin;
2542   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2543   PetscValidIntPointer(type,2);
2544   *type = ts->problem_type;
2545   PetscFunctionReturn(0);
2546 }
2547 
2548 /*@
2549    TSSetUp - Sets up the internal data structures for the later use
2550    of a timestepper.
2551 
2552    Collective on TS
2553 
2554    Input Parameter:
2555 .  ts - the TS context obtained from TSCreate()
2556 
2557    Notes:
2558    For basic use of the TS solvers the user need not explicitly call
2559    TSSetUp(), since these actions will automatically occur during
2560    the call to TSStep() or TSSolve().  However, if one wishes to control this
2561    phase separately, TSSetUp() should be called after TSCreate()
2562    and optional routines of the form TSSetXXX(), but before TSStep() and TSSolve().
2563 
2564    Level: advanced
2565 
2566 .keywords: TS, timestep, setup
2567 
2568 .seealso: TSCreate(), TSStep(), TSDestroy(), TSSolve()
2569 @*/
2570 PetscErrorCode  TSSetUp(TS ts)
2571 {
2572   PetscErrorCode ierr;
2573   DM             dm;
2574   PetscErrorCode (*func)(SNES,Vec,Vec,void*);
2575   PetscErrorCode (*jac)(SNES,Vec,Mat,Mat,void*);
2576   TSIFunction    ifun;
2577   TSIJacobian    ijac;
2578   TSI2Jacobian   i2jac;
2579   TSRHSJacobian  rhsjac;
2580   PetscBool      isnone;
2581 
2582   PetscFunctionBegin;
2583   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2584   if (ts->setupcalled) PetscFunctionReturn(0);
2585 
2586   if (!((PetscObject)ts)->type_name) {
2587     ierr = TSGetIFunction(ts,NULL,&ifun,NULL);CHKERRQ(ierr);
2588     ierr = TSSetType(ts,ifun ? TSBEULER : TSEULER);CHKERRQ(ierr);
2589   }
2590 
2591   if (!ts->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call TSSetSolution() first");
2592 
2593   ierr = TSGetRHSJacobian(ts,NULL,NULL,&rhsjac,NULL);CHKERRQ(ierr);
2594   if (ts->rhsjacobian.reuse && rhsjac == TSComputeRHSJacobianConstant) {
2595     Mat Amat,Pmat;
2596     SNES snes;
2597     ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2598     ierr = SNESGetJacobian(snes,&Amat,&Pmat,NULL,NULL);CHKERRQ(ierr);
2599     /* Matching matrices implies that an IJacobian is NOT set, because if it had been set, the IJacobian's matrix would
2600      * have displaced the RHS matrix */
2601     if (Amat && Amat == ts->Arhs) {
2602       /* we need to copy the values of the matrix because for the constant Jacobian case the user will never set the numerical values in this new location */
2603       ierr = MatDuplicate(ts->Arhs,MAT_COPY_VALUES,&Amat);CHKERRQ(ierr);
2604       ierr = SNESSetJacobian(snes,Amat,NULL,NULL,NULL);CHKERRQ(ierr);
2605       ierr = MatDestroy(&Amat);CHKERRQ(ierr);
2606     }
2607     if (Pmat && Pmat == ts->Brhs) {
2608       ierr = MatDuplicate(ts->Brhs,MAT_COPY_VALUES,&Pmat);CHKERRQ(ierr);
2609       ierr = SNESSetJacobian(snes,NULL,Pmat,NULL,NULL);CHKERRQ(ierr);
2610       ierr = MatDestroy(&Pmat);CHKERRQ(ierr);
2611     }
2612   }
2613 
2614   ierr = TSGetAdapt(ts,&ts->adapt);CHKERRQ(ierr);
2615   ierr = TSAdaptSetDefaultType(ts->adapt,ts->default_adapt_type);CHKERRQ(ierr);
2616 
2617   if (ts->ops->setup) {
2618     ierr = (*ts->ops->setup)(ts);CHKERRQ(ierr);
2619   }
2620 
2621   /* Attempt to check/preset a default value for the exact final time option */
2622   ierr = PetscObjectTypeCompare((PetscObject)ts->adapt,TSADAPTNONE,&isnone);CHKERRQ(ierr);
2623   if (!isnone && ts->exact_final_time == TS_EXACTFINALTIME_UNSPECIFIED)
2624     ts->exact_final_time = TS_EXACTFINALTIME_MATCHSTEP;
2625 
2626   /* In the case where we've set a DMTSFunction or what have you, we need the default SNESFunction
2627      to be set right but can't do it elsewhere due to the overreliance on ctx=ts.
2628    */
2629   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
2630   ierr = DMSNESGetFunction(dm,&func,NULL);CHKERRQ(ierr);
2631   if (!func) {
2632     ierr = DMSNESSetFunction(dm,SNESTSFormFunction,ts);CHKERRQ(ierr);
2633   }
2634   /* If the SNES doesn't have a jacobian set and the TS has an ijacobian or rhsjacobian set, set the SNES to use it.
2635      Otherwise, the SNES will use coloring internally to form the Jacobian.
2636    */
2637   ierr = DMSNESGetJacobian(dm,&jac,NULL);CHKERRQ(ierr);
2638   ierr = DMTSGetIJacobian(dm,&ijac,NULL);CHKERRQ(ierr);
2639   ierr = DMTSGetI2Jacobian(dm,&i2jac,NULL);CHKERRQ(ierr);
2640   ierr = DMTSGetRHSJacobian(dm,&rhsjac,NULL);CHKERRQ(ierr);
2641   if (!jac && (ijac || i2jac || rhsjac)) {
2642     ierr = DMSNESSetJacobian(dm,SNESTSFormJacobian,ts);CHKERRQ(ierr);
2643   }
2644 
2645   /* if time integration scheme has a starting method, call it */
2646   if (ts->ops->startingmethod) {
2647     ierr = (*ts->ops->startingmethod)(ts);CHKERRQ(ierr);
2648   }
2649 
2650   ts->setupcalled = PETSC_TRUE;
2651   PetscFunctionReturn(0);
2652 }
2653 
2654 /*@
2655    TSReset - Resets a TS context and removes any allocated Vecs and Mats.
2656 
2657    Collective on TS
2658 
2659    Input Parameter:
2660 .  ts - the TS context obtained from TSCreate()
2661 
2662    Level: beginner
2663 
2664 .keywords: TS, timestep, reset
2665 
2666 .seealso: TSCreate(), TSSetup(), TSDestroy()
2667 @*/
2668 PetscErrorCode  TSReset(TS ts)
2669 {
2670   TS_RHSSplitLink ilink = ts->tsrhssplit,next;
2671   PetscErrorCode  ierr;
2672 
2673   PetscFunctionBegin;
2674   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2675 
2676   if (ts->ops->reset) {
2677     ierr = (*ts->ops->reset)(ts);CHKERRQ(ierr);
2678   }
2679   if (ts->snes) {ierr = SNESReset(ts->snes);CHKERRQ(ierr);}
2680   if (ts->adapt) {ierr = TSAdaptReset(ts->adapt);CHKERRQ(ierr);}
2681 
2682   ierr = MatDestroy(&ts->Arhs);CHKERRQ(ierr);
2683   ierr = MatDestroy(&ts->Brhs);CHKERRQ(ierr);
2684   ierr = VecDestroy(&ts->Frhs);CHKERRQ(ierr);
2685   ierr = VecDestroy(&ts->vec_sol);CHKERRQ(ierr);
2686   ierr = VecDestroy(&ts->vec_dot);CHKERRQ(ierr);
2687   ierr = VecDestroy(&ts->vatol);CHKERRQ(ierr);
2688   ierr = VecDestroy(&ts->vrtol);CHKERRQ(ierr);
2689   ierr = VecDestroyVecs(ts->nwork,&ts->work);CHKERRQ(ierr);
2690 
2691   ierr = VecDestroyVecs(ts->numcost,&ts->vecs_drdy);CHKERRQ(ierr);
2692   ierr = VecDestroyVecs(ts->numcost,&ts->vecs_drdp);CHKERRQ(ierr);
2693 
2694   ierr = MatDestroy(&ts->Jacp);CHKERRQ(ierr);
2695   ierr = VecDestroy(&ts->vec_costintegral);CHKERRQ(ierr);
2696   ierr = VecDestroy(&ts->vec_costintegrand);CHKERRQ(ierr);
2697   ierr = MatDestroy(&ts->mat_sensip);CHKERRQ(ierr);
2698 
2699   while (ilink) {
2700     next = ilink->next;
2701     ierr = TSDestroy(&ilink->ts);CHKERRQ(ierr);
2702     ierr = PetscFree(ilink->splitname);CHKERRQ(ierr);
2703     ierr = ISDestroy(&ilink->is);CHKERRQ(ierr);
2704     ierr = PetscFree(ilink);CHKERRQ(ierr);
2705     ilink = next;
2706   }
2707   ts->num_rhs_splits = 0;
2708   ts->setupcalled = PETSC_FALSE;
2709   PetscFunctionReturn(0);
2710 }
2711 
2712 /*@
2713    TSDestroy - Destroys the timestepper context that was created
2714    with TSCreate().
2715 
2716    Collective on TS
2717 
2718    Input Parameter:
2719 .  ts - the TS context obtained from TSCreate()
2720 
2721    Level: beginner
2722 
2723 .keywords: TS, timestepper, destroy
2724 
2725 .seealso: TSCreate(), TSSetUp(), TSSolve()
2726 @*/
2727 PetscErrorCode  TSDestroy(TS *ts)
2728 {
2729   PetscErrorCode ierr;
2730 
2731   PetscFunctionBegin;
2732   if (!*ts) PetscFunctionReturn(0);
2733   PetscValidHeaderSpecific((*ts),TS_CLASSID,1);
2734   if (--((PetscObject)(*ts))->refct > 0) {*ts = 0; PetscFunctionReturn(0);}
2735 
2736   ierr = TSReset((*ts));CHKERRQ(ierr);
2737 
2738   /* if memory was published with SAWs then destroy it */
2739   ierr = PetscObjectSAWsViewOff((PetscObject)*ts);CHKERRQ(ierr);
2740   if ((*ts)->ops->destroy) {ierr = (*(*ts)->ops->destroy)((*ts));CHKERRQ(ierr);}
2741 
2742   ierr = TSTrajectoryDestroy(&(*ts)->trajectory);CHKERRQ(ierr);
2743 
2744   ierr = TSAdaptDestroy(&(*ts)->adapt);CHKERRQ(ierr);
2745   ierr = TSEventDestroy(&(*ts)->event);CHKERRQ(ierr);
2746 
2747   ierr = SNESDestroy(&(*ts)->snes);CHKERRQ(ierr);
2748   ierr = DMDestroy(&(*ts)->dm);CHKERRQ(ierr);
2749   ierr = TSMonitorCancel((*ts));CHKERRQ(ierr);
2750   ierr = TSAdjointMonitorCancel((*ts));CHKERRQ(ierr);
2751 
2752   ierr = PetscHeaderDestroy(ts);CHKERRQ(ierr);
2753   PetscFunctionReturn(0);
2754 }
2755 
2756 /*@
2757    TSGetSNES - Returns the SNES (nonlinear solver) associated with
2758    a TS (timestepper) context. Valid only for nonlinear problems.
2759 
2760    Not Collective, but SNES is parallel if TS is parallel
2761 
2762    Input Parameter:
2763 .  ts - the TS context obtained from TSCreate()
2764 
2765    Output Parameter:
2766 .  snes - the nonlinear solver context
2767 
2768    Notes:
2769    The user can then directly manipulate the SNES context to set various
2770    options, etc.  Likewise, the user can then extract and manipulate the
2771    KSP, KSP, and PC contexts as well.
2772 
2773    TSGetSNES() does not work for integrators that do not use SNES; in
2774    this case TSGetSNES() returns NULL in snes.
2775 
2776    Level: beginner
2777 
2778 .keywords: timestep, get, SNES
2779 @*/
2780 PetscErrorCode  TSGetSNES(TS ts,SNES *snes)
2781 {
2782   PetscErrorCode ierr;
2783 
2784   PetscFunctionBegin;
2785   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2786   PetscValidPointer(snes,2);
2787   if (!ts->snes) {
2788     ierr = SNESCreate(PetscObjectComm((PetscObject)ts),&ts->snes);CHKERRQ(ierr);
2789     ierr = PetscObjectSetOptions((PetscObject)ts->snes,((PetscObject)ts)->options);CHKERRQ(ierr);
2790     ierr = SNESSetFunction(ts->snes,NULL,SNESTSFormFunction,ts);CHKERRQ(ierr);
2791     ierr = PetscLogObjectParent((PetscObject)ts,(PetscObject)ts->snes);CHKERRQ(ierr);
2792     ierr = PetscObjectIncrementTabLevel((PetscObject)ts->snes,(PetscObject)ts,1);CHKERRQ(ierr);
2793     if (ts->dm) {ierr = SNESSetDM(ts->snes,ts->dm);CHKERRQ(ierr);}
2794     if (ts->problem_type == TS_LINEAR) {
2795       ierr = SNESSetType(ts->snes,SNESKSPONLY);CHKERRQ(ierr);
2796     }
2797   }
2798   *snes = ts->snes;
2799   PetscFunctionReturn(0);
2800 }
2801 
2802 /*@
2803    TSSetSNES - Set the SNES (nonlinear solver) to be used by the timestepping context
2804 
2805    Collective
2806 
2807    Input Parameter:
2808 +  ts - the TS context obtained from TSCreate()
2809 -  snes - the nonlinear solver context
2810 
2811    Notes:
2812    Most users should have the TS created by calling TSGetSNES()
2813 
2814    Level: developer
2815 
2816 .keywords: timestep, set, SNES
2817 @*/
2818 PetscErrorCode TSSetSNES(TS ts,SNES snes)
2819 {
2820   PetscErrorCode ierr;
2821   PetscErrorCode (*func)(SNES,Vec,Mat,Mat,void*);
2822 
2823   PetscFunctionBegin;
2824   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2825   PetscValidHeaderSpecific(snes,SNES_CLASSID,2);
2826   ierr = PetscObjectReference((PetscObject)snes);CHKERRQ(ierr);
2827   ierr = SNESDestroy(&ts->snes);CHKERRQ(ierr);
2828 
2829   ts->snes = snes;
2830 
2831   ierr = SNESSetFunction(ts->snes,NULL,SNESTSFormFunction,ts);CHKERRQ(ierr);
2832   ierr = SNESGetJacobian(ts->snes,NULL,NULL,&func,NULL);CHKERRQ(ierr);
2833   if (func == SNESTSFormJacobian) {
2834     ierr = SNESSetJacobian(ts->snes,NULL,NULL,SNESTSFormJacobian,ts);CHKERRQ(ierr);
2835   }
2836   PetscFunctionReturn(0);
2837 }
2838 
2839 /*@
2840    TSGetKSP - Returns the KSP (linear solver) associated with
2841    a TS (timestepper) context.
2842 
2843    Not Collective, but KSP is parallel if TS is parallel
2844 
2845    Input Parameter:
2846 .  ts - the TS context obtained from TSCreate()
2847 
2848    Output Parameter:
2849 .  ksp - the nonlinear solver context
2850 
2851    Notes:
2852    The user can then directly manipulate the KSP context to set various
2853    options, etc.  Likewise, the user can then extract and manipulate the
2854    KSP and PC contexts as well.
2855 
2856    TSGetKSP() does not work for integrators that do not use KSP;
2857    in this case TSGetKSP() returns NULL in ksp.
2858 
2859    Level: beginner
2860 
2861 .keywords: timestep, get, KSP
2862 @*/
2863 PetscErrorCode  TSGetKSP(TS ts,KSP *ksp)
2864 {
2865   PetscErrorCode ierr;
2866   SNES           snes;
2867 
2868   PetscFunctionBegin;
2869   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2870   PetscValidPointer(ksp,2);
2871   if (!((PetscObject)ts)->type_name) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"KSP is not created yet. Call TSSetType() first");
2872   if (ts->problem_type != TS_LINEAR) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Linear only; use TSGetSNES()");
2873   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2874   ierr = SNESGetKSP(snes,ksp);CHKERRQ(ierr);
2875   PetscFunctionReturn(0);
2876 }
2877 
2878 /* ----------- Routines to set solver parameters ---------- */
2879 
2880 /*@
2881    TSSetMaxSteps - Sets the maximum number of steps to use.
2882 
2883    Logically Collective on TS
2884 
2885    Input Parameters:
2886 +  ts - the TS context obtained from TSCreate()
2887 -  maxsteps - maximum number of steps to use
2888 
2889    Options Database Keys:
2890 .  -ts_max_steps <maxsteps> - Sets maxsteps
2891 
2892    Notes:
2893    The default maximum number of steps is 5000
2894 
2895    Level: intermediate
2896 
2897 .keywords: TS, timestep, set, maximum, steps
2898 
2899 .seealso: TSGetMaxSteps(), TSSetMaxTime(), TSSetExactFinalTime()
2900 @*/
2901 PetscErrorCode TSSetMaxSteps(TS ts,PetscInt maxsteps)
2902 {
2903   PetscFunctionBegin;
2904   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2905   PetscValidLogicalCollectiveInt(ts,maxsteps,2);
2906   if (maxsteps < 0 ) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_OUTOFRANGE,"Maximum number of steps must be non-negative");
2907   ts->max_steps = maxsteps;
2908   PetscFunctionReturn(0);
2909 }
2910 
2911 /*@
2912    TSGetMaxSteps - Gets the maximum number of steps to use.
2913 
2914    Not Collective
2915 
2916    Input Parameters:
2917 .  ts - the TS context obtained from TSCreate()
2918 
2919    Output Parameter:
2920 .  maxsteps - maximum number of steps to use
2921 
2922    Level: advanced
2923 
2924 .keywords: TS, timestep, get, maximum, steps
2925 
2926 .seealso: TSSetMaxSteps(), TSGetMaxTime(), TSSetMaxTime()
2927 @*/
2928 PetscErrorCode TSGetMaxSteps(TS ts,PetscInt *maxsteps)
2929 {
2930   PetscFunctionBegin;
2931   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2932   PetscValidIntPointer(maxsteps,2);
2933   *maxsteps = ts->max_steps;
2934   PetscFunctionReturn(0);
2935 }
2936 
2937 /*@
2938    TSSetMaxTime - Sets the maximum (or final) time for timestepping.
2939 
2940    Logically Collective on TS
2941 
2942    Input Parameters:
2943 +  ts - the TS context obtained from TSCreate()
2944 -  maxtime - final time to step to
2945 
2946    Options Database Keys:
2947 .  -ts_max_time <maxtime> - Sets maxtime
2948 
2949    Notes:
2950    The default maximum time is 5.0
2951 
2952    Level: intermediate
2953 
2954 .keywords: TS, timestep, set, maximum, time
2955 
2956 .seealso: TSGetMaxTime(), TSSetMaxSteps(), TSSetExactFinalTime()
2957 @*/
2958 PetscErrorCode TSSetMaxTime(TS ts,PetscReal maxtime)
2959 {
2960   PetscFunctionBegin;
2961   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2962   PetscValidLogicalCollectiveReal(ts,maxtime,2);
2963   ts->max_time = maxtime;
2964   PetscFunctionReturn(0);
2965 }
2966 
2967 /*@
2968    TSGetMaxTime - Gets the maximum (or final) time for timestepping.
2969 
2970    Not Collective
2971 
2972    Input Parameters:
2973 .  ts - the TS context obtained from TSCreate()
2974 
2975    Output Parameter:
2976 .  maxtime - final time to step to
2977 
2978    Level: advanced
2979 
2980 .keywords: TS, timestep, get, maximum, time
2981 
2982 .seealso: TSSetMaxTime(), TSGetMaxSteps(), TSSetMaxSteps()
2983 @*/
2984 PetscErrorCode TSGetMaxTime(TS ts,PetscReal *maxtime)
2985 {
2986   PetscFunctionBegin;
2987   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2988   PetscValidRealPointer(maxtime,2);
2989   *maxtime = ts->max_time;
2990   PetscFunctionReturn(0);
2991 }
2992 
2993 /*@
2994    TSSetInitialTimeStep - Deprecated, use TSSetTime() and TSSetTimeStep().
2995 
2996    Level: deprecated
2997 
2998 @*/
2999 PetscErrorCode  TSSetInitialTimeStep(TS ts,PetscReal initial_time,PetscReal time_step)
3000 {
3001   PetscErrorCode ierr;
3002   PetscFunctionBegin;
3003   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3004   ierr = TSSetTime(ts,initial_time);CHKERRQ(ierr);
3005   ierr = TSSetTimeStep(ts,time_step);CHKERRQ(ierr);
3006   PetscFunctionReturn(0);
3007 }
3008 
3009 /*@
3010    TSGetDuration - Deprecated, use TSGetMaxSteps() and TSGetMaxTime().
3011 
3012    Level: deprecated
3013 
3014 @*/
3015 PetscErrorCode TSGetDuration(TS ts, PetscInt *maxsteps, PetscReal *maxtime)
3016 {
3017   PetscFunctionBegin;
3018   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3019   if (maxsteps) {
3020     PetscValidIntPointer(maxsteps,2);
3021     *maxsteps = ts->max_steps;
3022   }
3023   if (maxtime) {
3024     PetscValidScalarPointer(maxtime,3);
3025     *maxtime = ts->max_time;
3026   }
3027   PetscFunctionReturn(0);
3028 }
3029 
3030 /*@
3031    TSSetDuration - Deprecated, use TSSetMaxSteps() and TSSetMaxTime().
3032 
3033    Level: deprecated
3034 
3035 @*/
3036 PetscErrorCode TSSetDuration(TS ts,PetscInt maxsteps,PetscReal maxtime)
3037 {
3038   PetscFunctionBegin;
3039   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3040   PetscValidLogicalCollectiveInt(ts,maxsteps,2);
3041   PetscValidLogicalCollectiveReal(ts,maxtime,2);
3042   if (maxsteps >= 0) ts->max_steps = maxsteps;
3043   if (maxtime != PETSC_DEFAULT) ts->max_time = maxtime;
3044   PetscFunctionReturn(0);
3045 }
3046 
3047 /*@
3048    TSGetTimeStepNumber - Deprecated, use TSGetStepNumber().
3049 
3050    Level: deprecated
3051 
3052 @*/
3053 PetscErrorCode TSGetTimeStepNumber(TS ts,PetscInt *steps) { return TSGetStepNumber(ts,steps); }
3054 
3055 /*@
3056    TSGetTotalSteps - Deprecated, use TSGetStepNumber().
3057 
3058    Level: deprecated
3059 
3060 @*/
3061 PetscErrorCode TSGetTotalSteps(TS ts,PetscInt *steps) { return TSGetStepNumber(ts,steps); }
3062 
3063 /*@
3064    TSSetSolution - Sets the initial solution vector
3065    for use by the TS routines.
3066 
3067    Logically Collective on TS and Vec
3068 
3069    Input Parameters:
3070 +  ts - the TS context obtained from TSCreate()
3071 -  u - the solution vector
3072 
3073    Level: beginner
3074 
3075 .keywords: TS, timestep, set, solution, initial values
3076 
3077 .seealso: TSSetSolutionFunction(), TSGetSolution(), TSCreate()
3078 @*/
3079 PetscErrorCode  TSSetSolution(TS ts,Vec u)
3080 {
3081   PetscErrorCode ierr;
3082   DM             dm;
3083 
3084   PetscFunctionBegin;
3085   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3086   PetscValidHeaderSpecific(u,VEC_CLASSID,2);
3087   ierr = PetscObjectReference((PetscObject)u);CHKERRQ(ierr);
3088   ierr = VecDestroy(&ts->vec_sol);CHKERRQ(ierr);
3089   ts->vec_sol = u;
3090 
3091   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
3092   ierr = DMShellSetGlobalVector(dm,u);CHKERRQ(ierr);
3093   PetscFunctionReturn(0);
3094 }
3095 
3096 /*@C
3097   TSSetPreStep - Sets the general-purpose function
3098   called once at the beginning of each time step.
3099 
3100   Logically Collective on TS
3101 
3102   Input Parameters:
3103 + ts   - The TS context obtained from TSCreate()
3104 - func - The function
3105 
3106   Calling sequence of func:
3107 . func (TS ts);
3108 
3109   Level: intermediate
3110 
3111 .keywords: TS, timestep
3112 .seealso: TSSetPreStage(), TSSetPostStage(), TSSetPostStep(), TSStep(), TSRestartStep()
3113 @*/
3114 PetscErrorCode  TSSetPreStep(TS ts, PetscErrorCode (*func)(TS))
3115 {
3116   PetscFunctionBegin;
3117   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3118   ts->prestep = func;
3119   PetscFunctionReturn(0);
3120 }
3121 
3122 /*@
3123   TSPreStep - Runs the user-defined pre-step function.
3124 
3125   Collective on TS
3126 
3127   Input Parameters:
3128 . ts   - The TS context obtained from TSCreate()
3129 
3130   Notes:
3131   TSPreStep() is typically used within time stepping implementations,
3132   so most users would not generally call this routine themselves.
3133 
3134   Level: developer
3135 
3136 .keywords: TS, timestep
3137 .seealso: TSSetPreStep(), TSPreStage(), TSPostStage(), TSPostStep()
3138 @*/
3139 PetscErrorCode  TSPreStep(TS ts)
3140 {
3141   PetscErrorCode ierr;
3142 
3143   PetscFunctionBegin;
3144   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3145   if (ts->prestep) {
3146     Vec              U;
3147     PetscObjectState sprev,spost;
3148 
3149     ierr = TSGetSolution(ts,&U);CHKERRQ(ierr);
3150     ierr = PetscObjectStateGet((PetscObject)U,&sprev);CHKERRQ(ierr);
3151     PetscStackCallStandard((*ts->prestep),(ts));
3152     ierr = PetscObjectStateGet((PetscObject)U,&spost);CHKERRQ(ierr);
3153     if (sprev != spost) {ierr = TSRestartStep(ts);CHKERRQ(ierr);}
3154   }
3155   PetscFunctionReturn(0);
3156 }
3157 
3158 /*@C
3159   TSSetPreStage - Sets the general-purpose function
3160   called once at the beginning of each stage.
3161 
3162   Logically Collective on TS
3163 
3164   Input Parameters:
3165 + ts   - The TS context obtained from TSCreate()
3166 - func - The function
3167 
3168   Calling sequence of func:
3169 . PetscErrorCode func(TS ts, PetscReal stagetime);
3170 
3171   Level: intermediate
3172 
3173   Note:
3174   There may be several stages per time step. If the solve for a given stage fails, the step may be rejected and retried.
3175   The time step number being computed can be queried using TSGetStepNumber() and the total size of the step being
3176   attempted can be obtained using TSGetTimeStep(). The time at the start of the step is available via TSGetTime().
3177 
3178 .keywords: TS, timestep
3179 .seealso: TSSetPostStage(), TSSetPreStep(), TSSetPostStep(), TSGetApplicationContext()
3180 @*/
3181 PetscErrorCode  TSSetPreStage(TS ts, PetscErrorCode (*func)(TS,PetscReal))
3182 {
3183   PetscFunctionBegin;
3184   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3185   ts->prestage = func;
3186   PetscFunctionReturn(0);
3187 }
3188 
3189 /*@C
3190   TSSetPostStage - Sets the general-purpose function
3191   called once at the end of each stage.
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 . PetscErrorCode func(TS ts, PetscReal stagetime, PetscInt stageindex, Vec* Y);
3201 
3202   Level: intermediate
3203 
3204   Note:
3205   There may be several stages per time step. If the solve for a given stage fails, the step may be rejected and retried.
3206   The time step number being computed can be queried using TSGetStepNumber() and the total size of the step being
3207   attempted can be obtained using TSGetTimeStep(). The time at the start of the step is available via TSGetTime().
3208 
3209 .keywords: TS, timestep
3210 .seealso: TSSetPreStage(), TSSetPreStep(), TSSetPostStep(), TSGetApplicationContext()
3211 @*/
3212 PetscErrorCode  TSSetPostStage(TS ts, PetscErrorCode (*func)(TS,PetscReal,PetscInt,Vec*))
3213 {
3214   PetscFunctionBegin;
3215   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3216   ts->poststage = func;
3217   PetscFunctionReturn(0);
3218 }
3219 
3220 /*@C
3221   TSSetPostEvaluate - Sets the general-purpose function
3222   called once at the end of each step evaluation.
3223 
3224   Logically Collective on TS
3225 
3226   Input Parameters:
3227 + ts   - The TS context obtained from TSCreate()
3228 - func - The function
3229 
3230   Calling sequence of func:
3231 . PetscErrorCode func(TS ts);
3232 
3233   Level: intermediate
3234 
3235   Note:
3236   Semantically, TSSetPostEvaluate() differs from TSSetPostStep() since the function it sets is called before event-handling
3237   thus guaranteeing the same solution (computed by the time-stepper) will be passed to it. On the other hand, TSPostStep()
3238   may be passed a different solution, possibly changed by the event handler. TSPostEvaluate() is called after the next step
3239   solution is evaluated allowing to modify it, if need be. The solution can be obtained with TSGetSolution(), the time step
3240   with TSGetTimeStep(), and the time at the start of the step is available via TSGetTime()
3241 
3242 .keywords: TS, timestep
3243 .seealso: TSSetPreStage(), TSSetPreStep(), TSSetPostStep(), TSGetApplicationContext()
3244 @*/
3245 PetscErrorCode  TSSetPostEvaluate(TS ts, PetscErrorCode (*func)(TS))
3246 {
3247   PetscFunctionBegin;
3248   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3249   ts->postevaluate = func;
3250   PetscFunctionReturn(0);
3251 }
3252 
3253 /*@
3254   TSPreStage - Runs the user-defined pre-stage function set using TSSetPreStage()
3255 
3256   Collective on TS
3257 
3258   Input Parameters:
3259 . ts          - The TS context obtained from TSCreate()
3260   stagetime   - The absolute time of the current stage
3261 
3262   Notes:
3263   TSPreStage() is typically used within time stepping implementations,
3264   most users would not generally call this routine themselves.
3265 
3266   Level: developer
3267 
3268 .keywords: TS, timestep
3269 .seealso: TSPostStage(), TSSetPreStep(), TSPreStep(), TSPostStep()
3270 @*/
3271 PetscErrorCode  TSPreStage(TS ts, PetscReal stagetime)
3272 {
3273   PetscFunctionBegin;
3274   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3275   if (ts->prestage) {
3276     PetscStackCallStandard((*ts->prestage),(ts,stagetime));
3277   }
3278   PetscFunctionReturn(0);
3279 }
3280 
3281 /*@
3282   TSPostStage - Runs the user-defined post-stage function set using TSSetPostStage()
3283 
3284   Collective on TS
3285 
3286   Input Parameters:
3287 . ts          - The TS context obtained from TSCreate()
3288   stagetime   - The absolute time of the current stage
3289   stageindex  - Stage number
3290   Y           - Array of vectors (of size = total number
3291                 of stages) with the stage solutions
3292 
3293   Notes:
3294   TSPostStage() is typically used within time stepping implementations,
3295   most users would not generally call this routine themselves.
3296 
3297   Level: developer
3298 
3299 .keywords: TS, timestep
3300 .seealso: TSPreStage(), TSSetPreStep(), TSPreStep(), TSPostStep()
3301 @*/
3302 PetscErrorCode  TSPostStage(TS ts, PetscReal stagetime, PetscInt stageindex, Vec *Y)
3303 {
3304   PetscFunctionBegin;
3305   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3306   if (ts->poststage) {
3307     PetscStackCallStandard((*ts->poststage),(ts,stagetime,stageindex,Y));
3308   }
3309   PetscFunctionReturn(0);
3310 }
3311 
3312 /*@
3313   TSPostEvaluate - Runs the user-defined post-evaluate function set using TSSetPostEvaluate()
3314 
3315   Collective on TS
3316 
3317   Input Parameters:
3318 . ts          - The TS context obtained from TSCreate()
3319 
3320   Notes:
3321   TSPostEvaluate() is typically used within time stepping implementations,
3322   most users would not generally call this routine themselves.
3323 
3324   Level: developer
3325 
3326 .keywords: TS, timestep
3327 .seealso: TSSetPostEvaluate(), TSSetPreStep(), TSPreStep(), TSPostStep()
3328 @*/
3329 PetscErrorCode  TSPostEvaluate(TS ts)
3330 {
3331   PetscErrorCode ierr;
3332 
3333   PetscFunctionBegin;
3334   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3335   if (ts->postevaluate) {
3336     Vec              U;
3337     PetscObjectState sprev,spost;
3338 
3339     ierr = TSGetSolution(ts,&U);CHKERRQ(ierr);
3340     ierr = PetscObjectStateGet((PetscObject)U,&sprev);CHKERRQ(ierr);
3341     PetscStackCallStandard((*ts->postevaluate),(ts));
3342     ierr = PetscObjectStateGet((PetscObject)U,&spost);CHKERRQ(ierr);
3343     if (sprev != spost) {ierr = TSRestartStep(ts);CHKERRQ(ierr);}
3344   }
3345   PetscFunctionReturn(0);
3346 }
3347 
3348 /*@C
3349   TSSetPostStep - Sets the general-purpose function
3350   called once at the end of each time step.
3351 
3352   Logically Collective on TS
3353 
3354   Input Parameters:
3355 + ts   - The TS context obtained from TSCreate()
3356 - func - The function
3357 
3358   Calling sequence of func:
3359 $ func (TS ts);
3360 
3361   Notes:
3362   The function set by TSSetPostStep() is called after each successful step. The solution vector X
3363   obtained by TSGetSolution() may be different than that computed at the step end if the event handler
3364   locates an event and TSPostEvent() modifies it. Use TSSetPostEvaluate() if an unmodified solution is needed instead.
3365 
3366   Level: intermediate
3367 
3368 .keywords: TS, timestep
3369 .seealso: TSSetPreStep(), TSSetPreStage(), TSSetPostEvaluate(), TSGetTimeStep(), TSGetStepNumber(), TSGetTime(), TSRestartStep()
3370 @*/
3371 PetscErrorCode  TSSetPostStep(TS ts, PetscErrorCode (*func)(TS))
3372 {
3373   PetscFunctionBegin;
3374   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
3375   ts->poststep = func;
3376   PetscFunctionReturn(0);
3377 }
3378 
3379 /*@
3380   TSPostStep - Runs the user-defined post-step function.
3381 
3382   Collective on TS
3383 
3384   Input Parameters:
3385 . ts   - The TS context obtained from TSCreate()
3386 
3387   Notes:
3388   TSPostStep() is typically used within time stepping implementations,
3389   so most users would not generally call this routine themselves.
3390 
3391   Level: developer
3392 
3393 .keywords: TS, timestep
3394 @*/
3395 PetscErrorCode  TSPostStep(TS ts)
3396 {
3397   PetscErrorCode ierr;
3398 
3399   PetscFunctionBegin;
3400   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3401   if (ts->poststep) {
3402     Vec              U;
3403     PetscObjectState sprev,spost;
3404 
3405     ierr = TSGetSolution(ts,&U);CHKERRQ(ierr);
3406     ierr = PetscObjectStateGet((PetscObject)U,&sprev);CHKERRQ(ierr);
3407     PetscStackCallStandard((*ts->poststep),(ts));
3408     ierr = PetscObjectStateGet((PetscObject)U,&spost);CHKERRQ(ierr);
3409     if (sprev != spost) {ierr = TSRestartStep(ts);CHKERRQ(ierr);}
3410   }
3411   PetscFunctionReturn(0);
3412 }
3413 
3414 /* ------------ Routines to set performance monitoring options ----------- */
3415 
3416 /*@C
3417    TSMonitorSet - Sets an ADDITIONAL function that is to be used at every
3418    timestep to display the iteration's  progress.
3419 
3420    Logically Collective on TS
3421 
3422    Input Parameters:
3423 +  ts - the TS context obtained from TSCreate()
3424 .  monitor - monitoring routine
3425 .  mctx - [optional] user-defined context for private data for the
3426              monitor routine (use NULL if no context is desired)
3427 -  monitordestroy - [optional] routine that frees monitor context
3428           (may be NULL)
3429 
3430    Calling sequence of monitor:
3431 $    PetscErrorCode monitor(TS ts,PetscInt steps,PetscReal time,Vec u,void *mctx)
3432 
3433 +    ts - the TS context
3434 .    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)
3435 .    time - current time
3436 .    u - current iterate
3437 -    mctx - [optional] monitoring context
3438 
3439    Notes:
3440    This routine adds an additional monitor to the list of monitors that
3441    already has been loaded.
3442 
3443    Fortran Notes:
3444     Only a single monitor function can be set for each TS object
3445 
3446    Level: intermediate
3447 
3448 .keywords: TS, timestep, set, monitor
3449 
3450 .seealso: TSMonitorDefault(), TSMonitorCancel()
3451 @*/
3452 PetscErrorCode  TSMonitorSet(TS ts,PetscErrorCode (*monitor)(TS,PetscInt,PetscReal,Vec,void*),void *mctx,PetscErrorCode (*mdestroy)(void**))
3453 {
3454   PetscErrorCode ierr;
3455   PetscInt       i;
3456   PetscBool      identical;
3457 
3458   PetscFunctionBegin;
3459   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3460   for (i=0; i<ts->numbermonitors;i++) {
3461     ierr = PetscMonitorCompare((PetscErrorCode (*)(void))monitor,mctx,mdestroy,(PetscErrorCode (*)(void))ts->monitor[i],ts->monitorcontext[i],ts->monitordestroy[i],&identical);CHKERRQ(ierr);
3462     if (identical) PetscFunctionReturn(0);
3463   }
3464   if (ts->numbermonitors >= MAXTSMONITORS) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Too many monitors set");
3465   ts->monitor[ts->numbermonitors]          = monitor;
3466   ts->monitordestroy[ts->numbermonitors]   = mdestroy;
3467   ts->monitorcontext[ts->numbermonitors++] = (void*)mctx;
3468   PetscFunctionReturn(0);
3469 }
3470 
3471 /*@C
3472    TSMonitorCancel - Clears all the monitors that have been set on a time-step object.
3473 
3474    Logically Collective on TS
3475 
3476    Input Parameters:
3477 .  ts - the TS context obtained from TSCreate()
3478 
3479    Notes:
3480    There is no way to remove a single, specific monitor.
3481 
3482    Level: intermediate
3483 
3484 .keywords: TS, timestep, set, monitor
3485 
3486 .seealso: TSMonitorDefault(), TSMonitorSet()
3487 @*/
3488 PetscErrorCode  TSMonitorCancel(TS ts)
3489 {
3490   PetscErrorCode ierr;
3491   PetscInt       i;
3492 
3493   PetscFunctionBegin;
3494   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3495   for (i=0; i<ts->numbermonitors; i++) {
3496     if (ts->monitordestroy[i]) {
3497       ierr = (*ts->monitordestroy[i])(&ts->monitorcontext[i]);CHKERRQ(ierr);
3498     }
3499   }
3500   ts->numbermonitors = 0;
3501   PetscFunctionReturn(0);
3502 }
3503 
3504 /*@C
3505    TSMonitorDefault - The Default monitor, prints the timestep and time for each step
3506 
3507    Level: intermediate
3508 
3509 .keywords: TS, set, monitor
3510 
3511 .seealso:  TSMonitorSet()
3512 @*/
3513 PetscErrorCode TSMonitorDefault(TS ts,PetscInt step,PetscReal ptime,Vec v,PetscViewerAndFormat *vf)
3514 {
3515   PetscErrorCode ierr;
3516   PetscViewer    viewer =  vf->viewer;
3517   PetscBool      iascii,ibinary;
3518 
3519   PetscFunctionBegin;
3520   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,4);
3521   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
3522   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&ibinary);CHKERRQ(ierr);
3523   ierr = PetscViewerPushFormat(viewer,vf->format);CHKERRQ(ierr);
3524   if (iascii) {
3525     ierr = PetscViewerASCIIAddTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
3526     if (step == -1){ /* this indicates it is an interpolated solution */
3527       ierr = PetscViewerASCIIPrintf(viewer,"Interpolated solution at time %g between steps %D and %D\n",(double)ptime,ts->steps-1,ts->steps);CHKERRQ(ierr);
3528     } else {
3529       ierr = PetscViewerASCIIPrintf(viewer,"%D TS dt %g time %g%s",step,(double)ts->time_step,(double)ptime,ts->steprollback ? " (r)\n" : "\n");CHKERRQ(ierr);
3530     }
3531     ierr = PetscViewerASCIISubtractTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
3532   } else if (ibinary) {
3533     PetscMPIInt rank;
3534     ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)viewer),&rank);CHKERRQ(ierr);
3535     if (!rank) {
3536       PetscBool skipHeader;
3537       PetscInt  classid = REAL_FILE_CLASSID;
3538 
3539       ierr = PetscViewerBinaryGetSkipHeader(viewer,&skipHeader);CHKERRQ(ierr);
3540       if (!skipHeader) {
3541          ierr = PetscViewerBinaryWrite(viewer,&classid,1,PETSC_INT,PETSC_FALSE);CHKERRQ(ierr);
3542        }
3543       ierr = PetscRealView(1,&ptime,viewer);CHKERRQ(ierr);
3544     } else {
3545       ierr = PetscRealView(0,&ptime,viewer);CHKERRQ(ierr);
3546     }
3547   }
3548   ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
3549   PetscFunctionReturn(0);
3550 }
3551 
3552 /*@C
3553    TSMonitorExtreme - Prints the extreme values of the solution at each timestep
3554 
3555    Level: intermediate
3556 
3557 .keywords: TS, set, monitor
3558 
3559 .seealso:  TSMonitorSet()
3560 @*/
3561 PetscErrorCode TSMonitorExtreme(TS ts,PetscInt step,PetscReal ptime,Vec v,PetscViewerAndFormat *vf)
3562 {
3563   PetscErrorCode ierr;
3564   PetscViewer    viewer =  vf->viewer;
3565   PetscBool      iascii;
3566   PetscReal      max,min;
3567 
3568 
3569   PetscFunctionBegin;
3570   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,4);
3571   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
3572   ierr = PetscViewerPushFormat(viewer,vf->format);CHKERRQ(ierr);
3573   if (iascii) {
3574     ierr = VecMax(v,NULL,&max);CHKERRQ(ierr);
3575     ierr = VecMin(v,NULL,&min);CHKERRQ(ierr);
3576     ierr = PetscViewerASCIIAddTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
3577     ierr = PetscViewerASCIIPrintf(viewer,"%D TS dt %g time %g%s max %g min %g\n",step,(double)ts->time_step,(double)ptime,ts->steprollback ? " (r)" : "",(double)max,(double)min);CHKERRQ(ierr);
3578     ierr = PetscViewerASCIISubtractTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
3579   }
3580   ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
3581   PetscFunctionReturn(0);
3582 }
3583 
3584 /*@
3585    TSInterpolate - Interpolate the solution computed during the previous step to an arbitrary location in the interval
3586 
3587    Collective on TS
3588 
3589    Input Argument:
3590 +  ts - time stepping context
3591 -  t - time to interpolate to
3592 
3593    Output Argument:
3594 .  U - state at given time
3595 
3596    Level: intermediate
3597 
3598    Developer Notes:
3599    TSInterpolate() and the storing of previous steps/stages should be generalized to support delay differential equations and continuous adjoints.
3600 
3601 .keywords: TS, set
3602 
3603 .seealso: TSSetExactFinalTime(), TSSolve()
3604 @*/
3605 PetscErrorCode TSInterpolate(TS ts,PetscReal t,Vec U)
3606 {
3607   PetscErrorCode ierr;
3608 
3609   PetscFunctionBegin;
3610   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3611   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
3612   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);
3613   if (!ts->ops->interpolate) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"%s does not provide interpolation",((PetscObject)ts)->type_name);
3614   ierr = (*ts->ops->interpolate)(ts,t,U);CHKERRQ(ierr);
3615   PetscFunctionReturn(0);
3616 }
3617 
3618 /*@
3619    TSStep - Steps one time step
3620 
3621    Collective on TS
3622 
3623    Input Parameter:
3624 .  ts - the TS context obtained from TSCreate()
3625 
3626    Level: developer
3627 
3628    Notes:
3629    The public interface for the ODE/DAE solvers is TSSolve(), you should almost for sure be using that routine and not this routine.
3630 
3631    The hook set using TSSetPreStep() is called before each attempt to take the step. In general, the time step size may
3632    be changed due to adaptive error controller or solve failures. Note that steps may contain multiple stages.
3633 
3634    This may over-step the final time provided in TSSetMaxTime() depending on the time-step used. TSSolve() interpolates to exactly the
3635    time provided in TSSetMaxTime(). One can use TSInterpolate() to determine an interpolated solution within the final timestep.
3636 
3637 .keywords: TS, timestep, solve
3638 
3639 .seealso: TSCreate(), TSSetUp(), TSDestroy(), TSSolve(), TSSetPreStep(), TSSetPreStage(), TSSetPostStage(), TSInterpolate()
3640 @*/
3641 PetscErrorCode  TSStep(TS ts)
3642 {
3643   PetscErrorCode   ierr;
3644   static PetscBool cite = PETSC_FALSE;
3645   PetscReal        ptime;
3646 
3647   PetscFunctionBegin;
3648   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3649   ierr = PetscCitationsRegister("@techreport{tspaper,\n"
3650                                 "  title       = {{PETSc/TS}: A Modern Scalable {DAE/ODE} Solver Library},\n"
3651                                 "  author      = {Shrirang Abhyankar and Jed Brown and Emil Constantinescu and Debojyoti Ghosh and Barry F. Smith},\n"
3652                                 "  type        = {Preprint},\n"
3653                                 "  number      = {ANL/MCS-P5061-0114},\n"
3654                                 "  institution = {Argonne National Laboratory},\n"
3655                                 "  year        = {2014}\n}\n",&cite);CHKERRQ(ierr);
3656 
3657   ierr = TSSetUp(ts);CHKERRQ(ierr);
3658   ierr = TSTrajectorySetUp(ts->trajectory,ts);CHKERRQ(ierr);
3659 
3660   if (ts->max_time >= PETSC_MAX_REAL && ts->max_steps == PETSC_MAX_INT) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONGSTATE,"You must call TSSetMaxTime() or TSSetMaxSteps(), or use -ts_max_time <time> or -ts_max_steps <steps>");
3661   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()");
3662   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");
3663 
3664   if (!ts->steps) ts->ptime_prev = ts->ptime;
3665   ptime = ts->ptime; ts->ptime_prev_rollback = ts->ptime_prev;
3666   ts->reason = TS_CONVERGED_ITERATING;
3667   if (!ts->ops->step) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSStep not implemented for type '%s'",((PetscObject)ts)->type_name);
3668   ierr = PetscLogEventBegin(TS_Step,ts,0,0,0);CHKERRQ(ierr);
3669   ierr = (*ts->ops->step)(ts);CHKERRQ(ierr);
3670   ierr = PetscLogEventEnd(TS_Step,ts,0,0,0);CHKERRQ(ierr);
3671   ts->ptime_prev = ptime;
3672   ts->steps++;
3673   ts->steprollback = PETSC_FALSE;
3674   ts->steprestart  = PETSC_FALSE;
3675 
3676   if (ts->reason < 0) {
3677     if (ts->errorifstepfailed) {
3678       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]);
3679       else SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_NOT_CONVERGED,"TSStep has failed due to %s",TSConvergedReasons[ts->reason]);
3680     }
3681   } else if (!ts->reason) {
3682     if (ts->steps >= ts->max_steps) ts->reason = TS_CONVERGED_ITS;
3683     else if (ts->ptime >= ts->max_time) ts->reason = TS_CONVERGED_TIME;
3684   }
3685   PetscFunctionReturn(0);
3686 }
3687 
3688 /*@
3689    TSEvaluateWLTE - Evaluate the weighted local truncation error norm
3690    at the end of a time step with a given order of accuracy.
3691 
3692    Collective on TS
3693 
3694    Input Arguments:
3695 +  ts - time stepping context
3696 .  wnormtype - norm type, either NORM_2 or NORM_INFINITY
3697 -  order - optional, desired order for the error evaluation or PETSC_DECIDE
3698 
3699    Output Arguments:
3700 +  order - optional, the actual order of the error evaluation
3701 -  wlte - the weighted local truncation error norm
3702 
3703    Level: advanced
3704 
3705    Notes:
3706    If the timestepper cannot evaluate the error in a particular step
3707    (eg. in the first step or restart steps after event handling),
3708    this routine returns wlte=-1.0 .
3709 
3710 .seealso: TSStep(), TSAdapt, TSErrorWeightedNorm()
3711 @*/
3712 PetscErrorCode TSEvaluateWLTE(TS ts,NormType wnormtype,PetscInt *order,PetscReal *wlte)
3713 {
3714   PetscErrorCode ierr;
3715 
3716   PetscFunctionBegin;
3717   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3718   PetscValidType(ts,1);
3719   PetscValidLogicalCollectiveEnum(ts,wnormtype,4);
3720   if (order) PetscValidIntPointer(order,3);
3721   if (order) PetscValidLogicalCollectiveInt(ts,*order,3);
3722   PetscValidRealPointer(wlte,4);
3723   if (wnormtype != NORM_2 && wnormtype != NORM_INFINITY) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"No support for norm type %s",NormTypes[wnormtype]);
3724   if (!ts->ops->evaluatewlte) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSEvaluateWLTE not implemented for type '%s'",((PetscObject)ts)->type_name);
3725   ierr = (*ts->ops->evaluatewlte)(ts,wnormtype,order,wlte);CHKERRQ(ierr);
3726   PetscFunctionReturn(0);
3727 }
3728 
3729 /*@
3730    TSEvaluateStep - Evaluate the solution at the end of a time step with a given order of accuracy.
3731 
3732    Collective on TS
3733 
3734    Input Arguments:
3735 +  ts - time stepping context
3736 .  order - desired order of accuracy
3737 -  done - whether the step was evaluated at this order (pass NULL to generate an error if not available)
3738 
3739    Output Arguments:
3740 .  U - state at the end of the current step
3741 
3742    Level: advanced
3743 
3744    Notes:
3745    This function cannot be called until all stages have been evaluated.
3746    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.
3747 
3748 .seealso: TSStep(), TSAdapt
3749 @*/
3750 PetscErrorCode TSEvaluateStep(TS ts,PetscInt order,Vec U,PetscBool *done)
3751 {
3752   PetscErrorCode ierr;
3753 
3754   PetscFunctionBegin;
3755   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3756   PetscValidType(ts,1);
3757   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
3758   if (!ts->ops->evaluatestep) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSEvaluateStep not implemented for type '%s'",((PetscObject)ts)->type_name);
3759   ierr = (*ts->ops->evaluatestep)(ts,order,U,done);CHKERRQ(ierr);
3760   PetscFunctionReturn(0);
3761 }
3762 
3763 /*@
3764    TSSolve - Steps the requested number of timesteps.
3765 
3766    Collective on TS
3767 
3768    Input Parameter:
3769 +  ts - the TS context obtained from TSCreate()
3770 -  u - the solution vector  (can be null if TSSetSolution() was used and TSSetExactFinalTime(ts,TS_EXACTFINALTIME_MATCHSTEP) was not used,
3771                              otherwise must contain the initial conditions and will contain the solution at the final requested time
3772 
3773    Level: beginner
3774 
3775    Notes:
3776    The final time returned by this function may be different from the time of the internally
3777    held state accessible by TSGetSolution() and TSGetTime() because the method may have
3778    stepped over the final time.
3779 
3780 .keywords: TS, timestep, solve
3781 
3782 .seealso: TSCreate(), TSSetSolution(), TSStep(), TSGetTime(), TSGetSolveTime()
3783 @*/
3784 PetscErrorCode TSSolve(TS ts,Vec u)
3785 {
3786   Vec               solution;
3787   PetscErrorCode    ierr;
3788 
3789   PetscFunctionBegin;
3790   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3791   if (u) PetscValidHeaderSpecific(u,VEC_CLASSID,2);
3792 
3793   if (ts->exact_final_time == TS_EXACTFINALTIME_INTERPOLATE && u) {   /* Need ts->vec_sol to be distinct so it is not overwritten when we interpolate at the end */
3794     if (!ts->vec_sol || u == ts->vec_sol) {
3795       ierr = VecDuplicate(u,&solution);CHKERRQ(ierr);
3796       ierr = TSSetSolution(ts,solution);CHKERRQ(ierr);
3797       ierr = VecDestroy(&solution);CHKERRQ(ierr); /* grant ownership */
3798     }
3799     ierr = VecCopy(u,ts->vec_sol);CHKERRQ(ierr);
3800     if (ts->forward_solve) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Sensitivity analysis does not support the mode TS_EXACTFINALTIME_INTERPOLATE");
3801   } else if (u) {
3802     ierr = TSSetSolution(ts,u);CHKERRQ(ierr);
3803   }
3804   ierr = TSSetUp(ts);CHKERRQ(ierr);
3805   ierr = TSTrajectorySetUp(ts->trajectory,ts);CHKERRQ(ierr);
3806 
3807   if (ts->max_time >= PETSC_MAX_REAL && ts->max_steps == PETSC_MAX_INT) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONGSTATE,"You must call TSSetMaxTime() or TSSetMaxSteps(), or use -ts_max_time <time> or -ts_max_steps <steps>");
3808   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()");
3809   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");
3810 
3811   if (ts->forward_solve) {
3812     ierr = TSForwardSetUp(ts);CHKERRQ(ierr);
3813   }
3814 
3815   /* reset number of steps only when the step is not restarted. ARKIMEX
3816      restarts the step after an event. Resetting these counters in such case causes
3817      TSTrajectory to incorrectly save the output files
3818   */
3819   /* reset time step and iteration counters */
3820   if (!ts->steps) {
3821     ts->ksp_its           = 0;
3822     ts->snes_its          = 0;
3823     ts->num_snes_failures = 0;
3824     ts->reject            = 0;
3825     ts->steprestart       = PETSC_TRUE;
3826     ts->steprollback      = PETSC_FALSE;
3827   }
3828   if (ts->exact_final_time == TS_EXACTFINALTIME_MATCHSTEP && ts->ptime + ts->time_step > ts->max_time) ts->time_step = ts->max_time - ts->ptime;
3829   ts->reason = TS_CONVERGED_ITERATING;
3830 
3831   ierr = TSViewFromOptions(ts,NULL,"-ts_view_pre");CHKERRQ(ierr);
3832 
3833   if (ts->ops->solve) { /* This private interface is transitional and should be removed when all implementations are updated. */
3834     ierr = (*ts->ops->solve)(ts);CHKERRQ(ierr);
3835     if (u) {ierr = VecCopy(ts->vec_sol,u);CHKERRQ(ierr);}
3836     ts->solvetime = ts->ptime;
3837     solution = ts->vec_sol;
3838   } else { /* Step the requested number of timesteps. */
3839     if (ts->steps >= ts->max_steps) ts->reason = TS_CONVERGED_ITS;
3840     else if (ts->ptime >= ts->max_time) ts->reason = TS_CONVERGED_TIME;
3841 
3842     if (!ts->steps) {
3843       ierr = TSTrajectorySet(ts->trajectory,ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
3844       ierr = TSEventInitialize(ts->event,ts,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
3845     }
3846 
3847     while (!ts->reason) {
3848       ierr = TSMonitor(ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
3849       if (!ts->steprollback) {
3850         ierr = TSPreStep(ts);CHKERRQ(ierr);
3851       }
3852       ierr = TSStep(ts);CHKERRQ(ierr);
3853       if (ts->testjacobian) {
3854         ierr = TSRHSJacobianTest(ts,NULL);CHKERRQ(ierr);
3855       }
3856       if (ts->testjacobiantranspose) {
3857         ierr = TSRHSJacobianTestTranspose(ts,NULL);CHKERRQ(ierr);
3858       }
3859       if (ts->vec_costintegral && ts->costintegralfwd) { /* Must evaluate the cost integral before event is handled. The cost integral value can also be rolled back. */
3860         ierr = TSForwardCostIntegral(ts);CHKERRQ(ierr);
3861       }
3862       if (ts->forward_solve) { /* compute forward sensitivities before event handling because postevent() may change RHS and jump conditions may have to be applied */
3863         ierr = TSForwardStep(ts);CHKERRQ(ierr);
3864       }
3865       ierr = TSPostEvaluate(ts);CHKERRQ(ierr);
3866       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. */
3867       if (ts->steprollback) {
3868         ierr = TSPostEvaluate(ts);CHKERRQ(ierr);
3869       }
3870       if (!ts->steprollback) {
3871         ierr = TSTrajectorySet(ts->trajectory,ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
3872         ierr = TSPostStep(ts);CHKERRQ(ierr);
3873       }
3874     }
3875     ierr = TSMonitor(ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
3876 
3877     if (ts->exact_final_time == TS_EXACTFINALTIME_INTERPOLATE && ts->ptime > ts->max_time) {
3878       ierr = TSInterpolate(ts,ts->max_time,u);CHKERRQ(ierr);
3879       ts->solvetime = ts->max_time;
3880       solution = u;
3881       ierr = TSMonitor(ts,-1,ts->solvetime,solution);CHKERRQ(ierr);
3882     } else {
3883       if (u) {ierr = VecCopy(ts->vec_sol,u);CHKERRQ(ierr);}
3884       ts->solvetime = ts->ptime;
3885       solution = ts->vec_sol;
3886     }
3887   }
3888 
3889   ierr = TSViewFromOptions(ts,NULL,"-ts_view");CHKERRQ(ierr);
3890   ierr = VecViewFromOptions(solution,NULL,"-ts_view_solution");CHKERRQ(ierr);
3891   ierr = PetscObjectSAWsBlock((PetscObject)ts);CHKERRQ(ierr);
3892   if (ts->adjoint_solve) {
3893     ierr = TSAdjointSolve(ts);CHKERRQ(ierr);
3894   }
3895   PetscFunctionReturn(0);
3896 }
3897 
3898 /*@C
3899    TSMonitor - Runs all user-provided monitor routines set using TSMonitorSet()
3900 
3901    Collective on TS
3902 
3903    Input Parameters:
3904 +  ts - time stepping context obtained from TSCreate()
3905 .  step - step number that has just completed
3906 .  ptime - model time of the state
3907 -  u - state at the current model time
3908 
3909    Notes:
3910    TSMonitor() is typically used automatically within the time stepping implementations.
3911    Users would almost never call this routine directly.
3912 
3913    A step of -1 indicates that the monitor is being called on a solution obtained by interpolating from computed solutions
3914 
3915    Level: developer
3916 
3917 .keywords: TS, timestep
3918 @*/
3919 PetscErrorCode TSMonitor(TS ts,PetscInt step,PetscReal ptime,Vec u)
3920 {
3921   DM             dm;
3922   PetscInt       i,n = ts->numbermonitors;
3923   PetscErrorCode ierr;
3924 
3925   PetscFunctionBegin;
3926   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3927   PetscValidHeaderSpecific(u,VEC_CLASSID,4);
3928 
3929   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
3930   ierr = DMSetOutputSequenceNumber(dm,step,ptime);CHKERRQ(ierr);
3931 
3932   ierr = VecLockReadPush(u);CHKERRQ(ierr);
3933   for (i=0; i<n; i++) {
3934     ierr = (*ts->monitor[i])(ts,step,ptime,u,ts->monitorcontext[i]);CHKERRQ(ierr);
3935   }
3936   ierr = VecLockReadPop(u);CHKERRQ(ierr);
3937   PetscFunctionReturn(0);
3938 }
3939 
3940 /* ------------------------------------------------------------------------*/
3941 /*@C
3942    TSMonitorLGCtxCreate - Creates a TSMonitorLGCtx context for use with
3943    TS to monitor the solution process graphically in various ways
3944 
3945    Collective on TS
3946 
3947    Input Parameters:
3948 +  host - the X display to open, or null for the local machine
3949 .  label - the title to put in the title bar
3950 .  x, y - the screen coordinates of the upper left coordinate of the window
3951 .  m, n - the screen width and height in pixels
3952 -  howoften - if positive then determines the frequency of the plotting, if -1 then only at the final time
3953 
3954    Output Parameter:
3955 .  ctx - the context
3956 
3957    Options Database Key:
3958 +  -ts_monitor_lg_timestep - automatically sets line graph monitor
3959 +  -ts_monitor_lg_timestep_log - automatically sets line graph monitor
3960 .  -ts_monitor_lg_solution - monitor the solution (or certain values of the solution by calling TSMonitorLGSetDisplayVariables() or TSMonitorLGCtxSetDisplayVariables())
3961 .  -ts_monitor_lg_error -  monitor the error
3962 .  -ts_monitor_lg_ksp_iterations - monitor the number of KSP iterations needed for each timestep
3963 .  -ts_monitor_lg_snes_iterations - monitor the number of SNES iterations needed for each timestep
3964 -  -lg_use_markers <true,false> - mark the data points (at each time step) on the plot; default is true
3965 
3966    Notes:
3967    Use TSMonitorLGCtxDestroy() to destroy.
3968 
3969    One can provide a function that transforms the solution before plotting it with TSMonitorLGCtxSetTransform() or TSMonitorLGSetTransform()
3970 
3971    Many of the functions that control the monitoring have two forms: TSMonitorLGSet/GetXXXX() and TSMonitorLGCtxSet/GetXXXX() the first take a TS object as the
3972    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
3973    as the first argument.
3974 
3975    One can control the names displayed for each solution or error variable with TSMonitorLGCtxSetVariableNames() or TSMonitorLGSetVariableNames()
3976 
3977    Level: intermediate
3978 
3979 .keywords: TS, monitor, line graph, residual
3980 
3981 .seealso: TSMonitorLGTimeStep(), TSMonitorSet(), TSMonitorLGSolution(), TSMonitorLGError(), TSMonitorDefault(), VecView(),
3982            TSMonitorLGCtxCreate(), TSMonitorLGCtxSetVariableNames(), TSMonitorLGCtxGetVariableNames(),
3983            TSMonitorLGSetVariableNames(), TSMonitorLGGetVariableNames(), TSMonitorLGSetDisplayVariables(), TSMonitorLGCtxSetDisplayVariables(),
3984            TSMonitorLGCtxSetTransform(), TSMonitorLGSetTransform(), TSMonitorLGError(), TSMonitorLGSNESIterations(), TSMonitorLGKSPIterations(),
3985            TSMonitorEnvelopeCtxCreate(), TSMonitorEnvelopeGetBounds(), TSMonitorEnvelopeCtxDestroy(), TSMonitorEnvelop()
3986 
3987 @*/
3988 PetscErrorCode  TSMonitorLGCtxCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscInt howoften,TSMonitorLGCtx *ctx)
3989 {
3990   PetscDraw      draw;
3991   PetscErrorCode ierr;
3992 
3993   PetscFunctionBegin;
3994   ierr = PetscNew(ctx);CHKERRQ(ierr);
3995   ierr = PetscDrawCreate(comm,host,label,x,y,m,n,&draw);CHKERRQ(ierr);
3996   ierr = PetscDrawSetFromOptions(draw);CHKERRQ(ierr);
3997   ierr = PetscDrawLGCreate(draw,1,&(*ctx)->lg);CHKERRQ(ierr);
3998   ierr = PetscDrawLGSetFromOptions((*ctx)->lg);CHKERRQ(ierr);
3999   ierr = PetscDrawDestroy(&draw);CHKERRQ(ierr);
4000   (*ctx)->howoften = howoften;
4001   PetscFunctionReturn(0);
4002 }
4003 
4004 PetscErrorCode TSMonitorLGTimeStep(TS ts,PetscInt step,PetscReal ptime,Vec v,void *monctx)
4005 {
4006   TSMonitorLGCtx ctx = (TSMonitorLGCtx) monctx;
4007   PetscReal      x   = ptime,y;
4008   PetscErrorCode ierr;
4009 
4010   PetscFunctionBegin;
4011   if (step < 0) PetscFunctionReturn(0); /* -1 indicates an interpolated solution */
4012   if (!step) {
4013     PetscDrawAxis axis;
4014     const char *ylabel = ctx->semilogy ? "Log Time Step" : "Time Step";
4015     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
4016     ierr = PetscDrawAxisSetLabels(axis,"Timestep as function of time","Time",ylabel);CHKERRQ(ierr);
4017     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
4018   }
4019   ierr = TSGetTimeStep(ts,&y);CHKERRQ(ierr);
4020   if (ctx->semilogy) y = PetscLog10Real(y);
4021   ierr = PetscDrawLGAddPoint(ctx->lg,&x,&y);CHKERRQ(ierr);
4022   if (((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason)) {
4023     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
4024     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
4025   }
4026   PetscFunctionReturn(0);
4027 }
4028 
4029 /*@C
4030    TSMonitorLGCtxDestroy - Destroys a line graph context that was created
4031    with TSMonitorLGCtxCreate().
4032 
4033    Collective on TSMonitorLGCtx
4034 
4035    Input Parameter:
4036 .  ctx - the monitor context
4037 
4038    Level: intermediate
4039 
4040 .keywords: TS, monitor, line graph, destroy
4041 
4042 .seealso: TSMonitorLGCtxCreate(),  TSMonitorSet(), TSMonitorLGTimeStep();
4043 @*/
4044 PetscErrorCode  TSMonitorLGCtxDestroy(TSMonitorLGCtx *ctx)
4045 {
4046   PetscErrorCode ierr;
4047 
4048   PetscFunctionBegin;
4049   if ((*ctx)->transformdestroy) {
4050     ierr = ((*ctx)->transformdestroy)((*ctx)->transformctx);CHKERRQ(ierr);
4051   }
4052   ierr = PetscDrawLGDestroy(&(*ctx)->lg);CHKERRQ(ierr);
4053   ierr = PetscStrArrayDestroy(&(*ctx)->names);CHKERRQ(ierr);
4054   ierr = PetscStrArrayDestroy(&(*ctx)->displaynames);CHKERRQ(ierr);
4055   ierr = PetscFree((*ctx)->displayvariables);CHKERRQ(ierr);
4056   ierr = PetscFree((*ctx)->displayvalues);CHKERRQ(ierr);
4057   ierr = PetscFree(*ctx);CHKERRQ(ierr);
4058   PetscFunctionReturn(0);
4059 }
4060 
4061 /*
4062 
4063   Creates a TS Monitor SPCtx for use with DM Swarm particle visualizations
4064 
4065 */
4066 PetscErrorCode TSMonitorSPCtxCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscInt howoften,TSMonitorSPCtx *ctx)
4067 {
4068   PetscDraw      draw;
4069   PetscErrorCode ierr;
4070 
4071   PetscFunctionBegin;
4072   ierr = PetscNew(ctx);CHKERRQ(ierr);
4073   ierr = PetscDrawCreate(comm,host,label,x,y,m,n,&draw);CHKERRQ(ierr);
4074   ierr = PetscDrawSetFromOptions(draw);CHKERRQ(ierr);
4075   ierr = PetscDrawSPCreate(draw,1,&(*ctx)->sp);CHKERRQ(ierr);
4076   ierr = PetscDrawDestroy(&draw);CHKERRQ(ierr);
4077   (*ctx)->howoften = howoften;
4078   PetscFunctionReturn(0);
4079 
4080 }
4081 
4082 /*
4083   Destroys a TSMonitorSPCtx that was created with TSMonitorSPCtxCreate
4084 */
4085 PetscErrorCode TSMonitorSPCtxDestroy(TSMonitorSPCtx *ctx)
4086 {
4087   PetscErrorCode ierr;
4088 
4089   PetscFunctionBegin;
4090 
4091   ierr = PetscDrawSPDestroy(&(*ctx)->sp);CHKERRQ(ierr);
4092   ierr = PetscFree(*ctx);CHKERRQ(ierr);
4093 
4094   PetscFunctionReturn(0);
4095 
4096 }
4097 
4098 /*@
4099    TSGetTime - Gets the time of the most recently completed step.
4100 
4101    Not Collective
4102 
4103    Input Parameter:
4104 .  ts - the TS context obtained from TSCreate()
4105 
4106    Output Parameter:
4107 .  t  - the current time. This time may not corresponds to the final time set with TSSetMaxTime(), use TSGetSolveTime().
4108 
4109    Level: beginner
4110 
4111    Note:
4112    When called during time step evaluation (e.g. during residual evaluation or via hooks set using TSSetPreStep(),
4113    TSSetPreStage(), TSSetPostStage(), or TSSetPostStep()), the time is the time at the start of the step being evaluated.
4114 
4115 .seealso:  TSGetSolveTime(), TSSetTime(), TSGetTimeStep()
4116 
4117 .keywords: TS, get, time
4118 @*/
4119 PetscErrorCode  TSGetTime(TS ts,PetscReal *t)
4120 {
4121   PetscFunctionBegin;
4122   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4123   PetscValidRealPointer(t,2);
4124   *t = ts->ptime;
4125   PetscFunctionReturn(0);
4126 }
4127 
4128 /*@
4129    TSGetPrevTime - Gets the starting time of the previously completed step.
4130 
4131    Not Collective
4132 
4133    Input Parameter:
4134 .  ts - the TS context obtained from TSCreate()
4135 
4136    Output Parameter:
4137 .  t  - the previous time
4138 
4139    Level: beginner
4140 
4141 .seealso: TSGetTime(), TSGetSolveTime(), TSGetTimeStep()
4142 
4143 .keywords: TS, get, time
4144 @*/
4145 PetscErrorCode  TSGetPrevTime(TS ts,PetscReal *t)
4146 {
4147   PetscFunctionBegin;
4148   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4149   PetscValidRealPointer(t,2);
4150   *t = ts->ptime_prev;
4151   PetscFunctionReturn(0);
4152 }
4153 
4154 /*@
4155    TSSetTime - Allows one to reset the time.
4156 
4157    Logically Collective on TS
4158 
4159    Input Parameters:
4160 +  ts - the TS context obtained from TSCreate()
4161 -  time - the time
4162 
4163    Level: intermediate
4164 
4165 .seealso: TSGetTime(), TSSetMaxSteps()
4166 
4167 .keywords: TS, set, time
4168 @*/
4169 PetscErrorCode  TSSetTime(TS ts, PetscReal t)
4170 {
4171   PetscFunctionBegin;
4172   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4173   PetscValidLogicalCollectiveReal(ts,t,2);
4174   ts->ptime = t;
4175   PetscFunctionReturn(0);
4176 }
4177 
4178 /*@C
4179    TSSetOptionsPrefix - Sets the prefix used for searching for all
4180    TS options in the database.
4181 
4182    Logically Collective on TS
4183 
4184    Input Parameter:
4185 +  ts     - The TS context
4186 -  prefix - The prefix to prepend to all option names
4187 
4188    Notes:
4189    A hyphen (-) must NOT be given at the beginning of the prefix name.
4190    The first character of all runtime options is AUTOMATICALLY the
4191    hyphen.
4192 
4193    Level: advanced
4194 
4195 .keywords: TS, set, options, prefix, database
4196 
4197 .seealso: TSSetFromOptions()
4198 
4199 @*/
4200 PetscErrorCode  TSSetOptionsPrefix(TS ts,const char prefix[])
4201 {
4202   PetscErrorCode ierr;
4203   SNES           snes;
4204 
4205   PetscFunctionBegin;
4206   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4207   ierr = PetscObjectSetOptionsPrefix((PetscObject)ts,prefix);CHKERRQ(ierr);
4208   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4209   ierr = SNESSetOptionsPrefix(snes,prefix);CHKERRQ(ierr);
4210   PetscFunctionReturn(0);
4211 }
4212 
4213 /*@C
4214    TSAppendOptionsPrefix - Appends to the prefix used for searching for all
4215    TS options in the database.
4216 
4217    Logically Collective on TS
4218 
4219    Input Parameter:
4220 +  ts     - The TS context
4221 -  prefix - The prefix to prepend to all option names
4222 
4223    Notes:
4224    A hyphen (-) must NOT be given at the beginning of the prefix name.
4225    The first character of all runtime options is AUTOMATICALLY the
4226    hyphen.
4227 
4228    Level: advanced
4229 
4230 .keywords: TS, append, options, prefix, database
4231 
4232 .seealso: TSGetOptionsPrefix()
4233 
4234 @*/
4235 PetscErrorCode  TSAppendOptionsPrefix(TS ts,const char prefix[])
4236 {
4237   PetscErrorCode ierr;
4238   SNES           snes;
4239 
4240   PetscFunctionBegin;
4241   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4242   ierr = PetscObjectAppendOptionsPrefix((PetscObject)ts,prefix);CHKERRQ(ierr);
4243   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4244   ierr = SNESAppendOptionsPrefix(snes,prefix);CHKERRQ(ierr);
4245   PetscFunctionReturn(0);
4246 }
4247 
4248 /*@C
4249    TSGetOptionsPrefix - Sets the prefix used for searching for all
4250    TS options in the database.
4251 
4252    Not Collective
4253 
4254    Input Parameter:
4255 .  ts - The TS context
4256 
4257    Output Parameter:
4258 .  prefix - A pointer to the prefix string used
4259 
4260    Notes:
4261     On the fortran side, the user should pass in a string 'prifix' of
4262    sufficient length to hold the prefix.
4263 
4264    Level: intermediate
4265 
4266 .keywords: TS, get, options, prefix, database
4267 
4268 .seealso: TSAppendOptionsPrefix()
4269 @*/
4270 PetscErrorCode  TSGetOptionsPrefix(TS ts,const char *prefix[])
4271 {
4272   PetscErrorCode ierr;
4273 
4274   PetscFunctionBegin;
4275   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4276   PetscValidPointer(prefix,2);
4277   ierr = PetscObjectGetOptionsPrefix((PetscObject)ts,prefix);CHKERRQ(ierr);
4278   PetscFunctionReturn(0);
4279 }
4280 
4281 /*@C
4282    TSGetRHSJacobian - Returns the Jacobian J at the present timestep.
4283 
4284    Not Collective, but parallel objects are returned if TS is parallel
4285 
4286    Input Parameter:
4287 .  ts  - The TS context obtained from TSCreate()
4288 
4289    Output Parameters:
4290 +  Amat - The (approximate) Jacobian J of G, where U_t = G(U,t)  (or NULL)
4291 .  Pmat - The matrix from which the preconditioner is constructed, usually the same as Amat  (or NULL)
4292 .  func - Function to compute the Jacobian of the RHS  (or NULL)
4293 -  ctx - User-defined context for Jacobian evaluation routine  (or NULL)
4294 
4295    Notes:
4296     You can pass in NULL for any return argument you do not need.
4297 
4298    Level: intermediate
4299 
4300 .seealso: TSGetTimeStep(), TSGetMatrices(), TSGetTime(), TSGetStepNumber()
4301 
4302 .keywords: TS, timestep, get, matrix, Jacobian
4303 @*/
4304 PetscErrorCode  TSGetRHSJacobian(TS ts,Mat *Amat,Mat *Pmat,TSRHSJacobian *func,void **ctx)
4305 {
4306   PetscErrorCode ierr;
4307   DM             dm;
4308 
4309   PetscFunctionBegin;
4310   if (Amat || Pmat) {
4311     SNES snes;
4312     ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4313     ierr = SNESSetUpMatrices(snes);CHKERRQ(ierr);
4314     ierr = SNESGetJacobian(snes,Amat,Pmat,NULL,NULL);CHKERRQ(ierr);
4315   }
4316   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
4317   ierr = DMTSGetRHSJacobian(dm,func,ctx);CHKERRQ(ierr);
4318   PetscFunctionReturn(0);
4319 }
4320 
4321 /*@C
4322    TSGetIJacobian - Returns the implicit Jacobian at the present timestep.
4323 
4324    Not Collective, but parallel objects are returned if TS is parallel
4325 
4326    Input Parameter:
4327 .  ts  - The TS context obtained from TSCreate()
4328 
4329    Output Parameters:
4330 +  Amat  - The (approximate) Jacobian of F(t,U,U_t)
4331 .  Pmat - The matrix from which the preconditioner is constructed, often the same as Amat
4332 .  f   - The function to compute the matrices
4333 - ctx - User-defined context for Jacobian evaluation routine
4334 
4335    Notes:
4336     You can pass in NULL for any return argument you do not need.
4337 
4338    Level: advanced
4339 
4340 .seealso: TSGetTimeStep(), TSGetRHSJacobian(), TSGetMatrices(), TSGetTime(), TSGetStepNumber()
4341 
4342 .keywords: TS, timestep, get, matrix, Jacobian
4343 @*/
4344 PetscErrorCode  TSGetIJacobian(TS ts,Mat *Amat,Mat *Pmat,TSIJacobian *f,void **ctx)
4345 {
4346   PetscErrorCode ierr;
4347   DM             dm;
4348 
4349   PetscFunctionBegin;
4350   if (Amat || Pmat) {
4351     SNES snes;
4352     ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4353     ierr = SNESSetUpMatrices(snes);CHKERRQ(ierr);
4354     ierr = SNESGetJacobian(snes,Amat,Pmat,NULL,NULL);CHKERRQ(ierr);
4355   }
4356   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
4357   ierr = DMTSGetIJacobian(dm,f,ctx);CHKERRQ(ierr);
4358   PetscFunctionReturn(0);
4359 }
4360 
4361 /*@C
4362    TSMonitorDrawSolution - Monitors progress of the TS solvers by calling
4363    VecView() for the solution at each timestep
4364 
4365    Collective on TS
4366 
4367    Input Parameters:
4368 +  ts - the TS context
4369 .  step - current time-step
4370 .  ptime - current time
4371 -  dummy - either a viewer or NULL
4372 
4373    Options Database:
4374 .   -ts_monitor_draw_solution_initial - show initial solution as well as current solution
4375 
4376    Notes:
4377     the initial solution and current solution are not display with a common axis scaling so generally the option -ts_monitor_draw_solution_initial
4378        will look bad
4379 
4380    Level: intermediate
4381 
4382 .keywords: TS,  vector, monitor, view
4383 
4384 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
4385 @*/
4386 PetscErrorCode  TSMonitorDrawSolution(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
4387 {
4388   PetscErrorCode   ierr;
4389   TSMonitorDrawCtx ictx = (TSMonitorDrawCtx)dummy;
4390   PetscDraw        draw;
4391 
4392   PetscFunctionBegin;
4393   if (!step && ictx->showinitial) {
4394     if (!ictx->initialsolution) {
4395       ierr = VecDuplicate(u,&ictx->initialsolution);CHKERRQ(ierr);
4396     }
4397     ierr = VecCopy(u,ictx->initialsolution);CHKERRQ(ierr);
4398   }
4399   if (!(((ictx->howoften > 0) && (!(step % ictx->howoften))) || ((ictx->howoften == -1) && ts->reason))) PetscFunctionReturn(0);
4400 
4401   if (ictx->showinitial) {
4402     PetscReal pause;
4403     ierr = PetscViewerDrawGetPause(ictx->viewer,&pause);CHKERRQ(ierr);
4404     ierr = PetscViewerDrawSetPause(ictx->viewer,0.0);CHKERRQ(ierr);
4405     ierr = VecView(ictx->initialsolution,ictx->viewer);CHKERRQ(ierr);
4406     ierr = PetscViewerDrawSetPause(ictx->viewer,pause);CHKERRQ(ierr);
4407     ierr = PetscViewerDrawSetHold(ictx->viewer,PETSC_TRUE);CHKERRQ(ierr);
4408   }
4409   ierr = VecView(u,ictx->viewer);CHKERRQ(ierr);
4410   if (ictx->showtimestepandtime) {
4411     PetscReal xl,yl,xr,yr,h;
4412     char      time[32];
4413 
4414     ierr = PetscViewerDrawGetDraw(ictx->viewer,0,&draw);CHKERRQ(ierr);
4415     ierr = PetscSNPrintf(time,32,"Timestep %d Time %g",(int)step,(double)ptime);CHKERRQ(ierr);
4416     ierr = PetscDrawGetCoordinates(draw,&xl,&yl,&xr,&yr);CHKERRQ(ierr);
4417     h    = yl + .95*(yr - yl);
4418     ierr = PetscDrawStringCentered(draw,.5*(xl+xr),h,PETSC_DRAW_BLACK,time);CHKERRQ(ierr);
4419     ierr = PetscDrawFlush(draw);CHKERRQ(ierr);
4420   }
4421 
4422   if (ictx->showinitial) {
4423     ierr = PetscViewerDrawSetHold(ictx->viewer,PETSC_FALSE);CHKERRQ(ierr);
4424   }
4425   PetscFunctionReturn(0);
4426 }
4427 
4428 /*@C
4429    TSMonitorDrawSolutionPhase - Monitors progress of the TS solvers by plotting the solution as a phase diagram
4430 
4431    Collective on TS
4432 
4433    Input Parameters:
4434 +  ts - the TS context
4435 .  step - current time-step
4436 .  ptime - current time
4437 -  dummy - either a viewer or NULL
4438 
4439    Level: intermediate
4440 
4441 .keywords: TS,  vector, monitor, view
4442 
4443 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
4444 @*/
4445 PetscErrorCode  TSMonitorDrawSolutionPhase(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
4446 {
4447   PetscErrorCode    ierr;
4448   TSMonitorDrawCtx  ictx = (TSMonitorDrawCtx)dummy;
4449   PetscDraw         draw;
4450   PetscDrawAxis     axis;
4451   PetscInt          n;
4452   PetscMPIInt       size;
4453   PetscReal         U0,U1,xl,yl,xr,yr,h;
4454   char              time[32];
4455   const PetscScalar *U;
4456 
4457   PetscFunctionBegin;
4458   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)ts),&size);CHKERRQ(ierr);
4459   if (size != 1) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Only allowed for sequential runs");
4460   ierr = VecGetSize(u,&n);CHKERRQ(ierr);
4461   if (n != 2) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Only for ODEs with two unknowns");
4462 
4463   ierr = PetscViewerDrawGetDraw(ictx->viewer,0,&draw);CHKERRQ(ierr);
4464   ierr = PetscViewerDrawGetDrawAxis(ictx->viewer,0,&axis);CHKERRQ(ierr);
4465   ierr = PetscDrawAxisGetLimits(axis,&xl,&xr,&yl,&yr);CHKERRQ(ierr);
4466   if (!step) {
4467     ierr = PetscDrawClear(draw);CHKERRQ(ierr);
4468     ierr = PetscDrawAxisDraw(axis);CHKERRQ(ierr);
4469   }
4470 
4471   ierr = VecGetArrayRead(u,&U);CHKERRQ(ierr);
4472   U0 = PetscRealPart(U[0]);
4473   U1 = PetscRealPart(U[1]);
4474   ierr = VecRestoreArrayRead(u,&U);CHKERRQ(ierr);
4475   if ((U0 < xl) || (U1 < yl) || (U0 > xr) || (U1 > yr)) PetscFunctionReturn(0);
4476 
4477   ierr = PetscDrawCollectiveBegin(draw);CHKERRQ(ierr);
4478   ierr = PetscDrawPoint(draw,U0,U1,PETSC_DRAW_BLACK);CHKERRQ(ierr);
4479   if (ictx->showtimestepandtime) {
4480     ierr = PetscDrawGetCoordinates(draw,&xl,&yl,&xr,&yr);CHKERRQ(ierr);
4481     ierr = PetscSNPrintf(time,32,"Timestep %d Time %g",(int)step,(double)ptime);CHKERRQ(ierr);
4482     h    = yl + .95*(yr - yl);
4483     ierr = PetscDrawStringCentered(draw,.5*(xl+xr),h,PETSC_DRAW_BLACK,time);CHKERRQ(ierr);
4484   }
4485   ierr = PetscDrawCollectiveEnd(draw);CHKERRQ(ierr);
4486   ierr = PetscDrawFlush(draw);CHKERRQ(ierr);
4487   ierr = PetscDrawPause(draw);CHKERRQ(ierr);
4488   ierr = PetscDrawSave(draw);CHKERRQ(ierr);
4489   PetscFunctionReturn(0);
4490 }
4491 
4492 /*@C
4493    TSMonitorDrawCtxDestroy - Destroys the monitor context for TSMonitorDrawSolution()
4494 
4495    Collective on TS
4496 
4497    Input Parameters:
4498 .    ctx - the monitor context
4499 
4500    Level: intermediate
4501 
4502 .keywords: TS,  vector, monitor, view
4503 
4504 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorDrawSolution(), TSMonitorDrawError()
4505 @*/
4506 PetscErrorCode  TSMonitorDrawCtxDestroy(TSMonitorDrawCtx *ictx)
4507 {
4508   PetscErrorCode ierr;
4509 
4510   PetscFunctionBegin;
4511   ierr = PetscViewerDestroy(&(*ictx)->viewer);CHKERRQ(ierr);
4512   ierr = VecDestroy(&(*ictx)->initialsolution);CHKERRQ(ierr);
4513   ierr = PetscFree(*ictx);CHKERRQ(ierr);
4514   PetscFunctionReturn(0);
4515 }
4516 
4517 /*@C
4518    TSMonitorDrawCtxCreate - Creates the monitor context for TSMonitorDrawCtx
4519 
4520    Collective on TS
4521 
4522    Input Parameter:
4523 .    ts - time-step context
4524 
4525    Output Patameter:
4526 .    ctx - the monitor context
4527 
4528    Options Database:
4529 .   -ts_monitor_draw_solution_initial - show initial solution as well as current solution
4530 
4531    Level: intermediate
4532 
4533 .keywords: TS,  vector, monitor, view
4534 
4535 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorDrawCtx()
4536 @*/
4537 PetscErrorCode  TSMonitorDrawCtxCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscInt howoften,TSMonitorDrawCtx *ctx)
4538 {
4539   PetscErrorCode   ierr;
4540 
4541   PetscFunctionBegin;
4542   ierr = PetscNew(ctx);CHKERRQ(ierr);
4543   ierr = PetscViewerDrawOpen(comm,host,label,x,y,m,n,&(*ctx)->viewer);CHKERRQ(ierr);
4544   ierr = PetscViewerSetFromOptions((*ctx)->viewer);CHKERRQ(ierr);
4545 
4546   (*ctx)->howoften    = howoften;
4547   (*ctx)->showinitial = PETSC_FALSE;
4548   ierr = PetscOptionsGetBool(NULL,NULL,"-ts_monitor_draw_solution_initial",&(*ctx)->showinitial,NULL);CHKERRQ(ierr);
4549 
4550   (*ctx)->showtimestepandtime = PETSC_FALSE;
4551   ierr = PetscOptionsGetBool(NULL,NULL,"-ts_monitor_draw_solution_show_time",&(*ctx)->showtimestepandtime,NULL);CHKERRQ(ierr);
4552   PetscFunctionReturn(0);
4553 }
4554 
4555 /*@C
4556    TSMonitorDrawSolutionFunction - Monitors progress of the TS solvers by calling
4557    VecView() for the solution provided by TSSetSolutionFunction() at each timestep
4558 
4559    Collective on TS
4560 
4561    Input Parameters:
4562 +  ts - the TS context
4563 .  step - current time-step
4564 .  ptime - current time
4565 -  dummy - either a viewer or NULL
4566 
4567    Options Database:
4568 .  -ts_monitor_draw_solution_function - Monitor error graphically, requires user to have provided TSSetSolutionFunction()
4569 
4570    Level: intermediate
4571 
4572 .keywords: TS,  vector, monitor, view
4573 
4574 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSSetSolutionFunction()
4575 @*/
4576 PetscErrorCode  TSMonitorDrawSolutionFunction(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
4577 {
4578   PetscErrorCode   ierr;
4579   TSMonitorDrawCtx ctx    = (TSMonitorDrawCtx)dummy;
4580   PetscViewer      viewer = ctx->viewer;
4581   Vec              work;
4582 
4583   PetscFunctionBegin;
4584   if (!(((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason))) PetscFunctionReturn(0);
4585   ierr = VecDuplicate(u,&work);CHKERRQ(ierr);
4586   ierr = TSComputeSolutionFunction(ts,ptime,work);CHKERRQ(ierr);
4587   ierr = VecView(work,viewer);CHKERRQ(ierr);
4588   ierr = VecDestroy(&work);CHKERRQ(ierr);
4589   PetscFunctionReturn(0);
4590 }
4591 
4592 /*@C
4593    TSMonitorDrawError - Monitors progress of the TS solvers by calling
4594    VecView() for the error at each timestep
4595 
4596    Collective on TS
4597 
4598    Input Parameters:
4599 +  ts - the TS context
4600 .  step - current time-step
4601 .  ptime - current time
4602 -  dummy - either a viewer or NULL
4603 
4604    Options Database:
4605 .  -ts_monitor_draw_error - Monitor error graphically, requires user to have provided TSSetSolutionFunction()
4606 
4607    Level: intermediate
4608 
4609 .keywords: TS,  vector, monitor, view
4610 
4611 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSSetSolutionFunction()
4612 @*/
4613 PetscErrorCode  TSMonitorDrawError(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
4614 {
4615   PetscErrorCode   ierr;
4616   TSMonitorDrawCtx ctx    = (TSMonitorDrawCtx)dummy;
4617   PetscViewer      viewer = ctx->viewer;
4618   Vec              work;
4619 
4620   PetscFunctionBegin;
4621   if (!(((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason))) PetscFunctionReturn(0);
4622   ierr = VecDuplicate(u,&work);CHKERRQ(ierr);
4623   ierr = TSComputeSolutionFunction(ts,ptime,work);CHKERRQ(ierr);
4624   ierr = VecAXPY(work,-1.0,u);CHKERRQ(ierr);
4625   ierr = VecView(work,viewer);CHKERRQ(ierr);
4626   ierr = VecDestroy(&work);CHKERRQ(ierr);
4627   PetscFunctionReturn(0);
4628 }
4629 
4630 #include <petsc/private/dmimpl.h>
4631 /*@
4632    TSSetDM - Sets the DM that may be used by some nonlinear solvers or preconditioners under the TS
4633 
4634    Logically Collective on TS and DM
4635 
4636    Input Parameters:
4637 +  ts - the ODE integrator object
4638 -  dm - the dm, cannot be NULL
4639 
4640    Notes:
4641    A DM can only be used for solving one problem at a time because information about the problem is stored on the DM,
4642    even when not using interfaces like DMTSSetIFunction().  Use DMClone() to get a distinct DM when solving
4643    different problems using the same function space.
4644 
4645    Level: intermediate
4646 
4647 .seealso: TSGetDM(), SNESSetDM(), SNESGetDM()
4648 @*/
4649 PetscErrorCode  TSSetDM(TS ts,DM dm)
4650 {
4651   PetscErrorCode ierr;
4652   SNES           snes;
4653   DMTS           tsdm;
4654 
4655   PetscFunctionBegin;
4656   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4657   PetscValidHeaderSpecific(dm,DM_CLASSID,2);
4658   ierr = PetscObjectReference((PetscObject)dm);CHKERRQ(ierr);
4659   if (ts->dm) {               /* Move the DMTS context over to the new DM unless the new DM already has one */
4660     if (ts->dm->dmts && !dm->dmts) {
4661       ierr = DMCopyDMTS(ts->dm,dm);CHKERRQ(ierr);
4662       ierr = DMGetDMTS(ts->dm,&tsdm);CHKERRQ(ierr);
4663       if (tsdm->originaldm == ts->dm) { /* Grant write privileges to the replacement DM */
4664         tsdm->originaldm = dm;
4665       }
4666     }
4667     ierr = DMDestroy(&ts->dm);CHKERRQ(ierr);
4668   }
4669   ts->dm = dm;
4670 
4671   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4672   ierr = SNESSetDM(snes,dm);CHKERRQ(ierr);
4673   PetscFunctionReturn(0);
4674 }
4675 
4676 /*@
4677    TSGetDM - Gets the DM that may be used by some preconditioners
4678 
4679    Not Collective
4680 
4681    Input Parameter:
4682 . ts - the preconditioner context
4683 
4684    Output Parameter:
4685 .  dm - the dm
4686 
4687    Level: intermediate
4688 
4689 .seealso: TSSetDM(), SNESSetDM(), SNESGetDM()
4690 @*/
4691 PetscErrorCode  TSGetDM(TS ts,DM *dm)
4692 {
4693   PetscErrorCode ierr;
4694 
4695   PetscFunctionBegin;
4696   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4697   if (!ts->dm) {
4698     ierr = DMShellCreate(PetscObjectComm((PetscObject)ts),&ts->dm);CHKERRQ(ierr);
4699     if (ts->snes) {ierr = SNESSetDM(ts->snes,ts->dm);CHKERRQ(ierr);}
4700   }
4701   *dm = ts->dm;
4702   PetscFunctionReturn(0);
4703 }
4704 
4705 /*@
4706    SNESTSFormFunction - Function to evaluate nonlinear residual
4707 
4708    Logically Collective on SNES
4709 
4710    Input Parameter:
4711 + snes - nonlinear solver
4712 . U - the current state at which to evaluate the residual
4713 - ctx - user context, must be a TS
4714 
4715    Output Parameter:
4716 . F - the nonlinear residual
4717 
4718    Notes:
4719    This function is not normally called by users and is automatically registered with the SNES used by TS.
4720    It is most frequently passed to MatFDColoringSetFunction().
4721 
4722    Level: advanced
4723 
4724 .seealso: SNESSetFunction(), MatFDColoringSetFunction()
4725 @*/
4726 PetscErrorCode  SNESTSFormFunction(SNES snes,Vec U,Vec F,void *ctx)
4727 {
4728   TS             ts = (TS)ctx;
4729   PetscErrorCode ierr;
4730 
4731   PetscFunctionBegin;
4732   PetscValidHeaderSpecific(snes,SNES_CLASSID,1);
4733   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
4734   PetscValidHeaderSpecific(F,VEC_CLASSID,3);
4735   PetscValidHeaderSpecific(ts,TS_CLASSID,4);
4736   ierr = (ts->ops->snesfunction)(snes,U,F,ts);CHKERRQ(ierr);
4737   PetscFunctionReturn(0);
4738 }
4739 
4740 /*@
4741    SNESTSFormJacobian - Function to evaluate the Jacobian
4742 
4743    Collective on SNES
4744 
4745    Input Parameter:
4746 + snes - nonlinear solver
4747 . U - the current state at which to evaluate the residual
4748 - ctx - user context, must be a TS
4749 
4750    Output Parameter:
4751 + A - the Jacobian
4752 . B - the preconditioning matrix (may be the same as A)
4753 - flag - indicates any structure change in the matrix
4754 
4755    Notes:
4756    This function is not normally called by users and is automatically registered with the SNES used by TS.
4757 
4758    Level: developer
4759 
4760 .seealso: SNESSetJacobian()
4761 @*/
4762 PetscErrorCode  SNESTSFormJacobian(SNES snes,Vec U,Mat A,Mat B,void *ctx)
4763 {
4764   TS             ts = (TS)ctx;
4765   PetscErrorCode ierr;
4766 
4767   PetscFunctionBegin;
4768   PetscValidHeaderSpecific(snes,SNES_CLASSID,1);
4769   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
4770   PetscValidPointer(A,3);
4771   PetscValidHeaderSpecific(A,MAT_CLASSID,3);
4772   PetscValidPointer(B,4);
4773   PetscValidHeaderSpecific(B,MAT_CLASSID,4);
4774   PetscValidHeaderSpecific(ts,TS_CLASSID,6);
4775   ierr = (ts->ops->snesjacobian)(snes,U,A,B,ts);CHKERRQ(ierr);
4776   PetscFunctionReturn(0);
4777 }
4778 
4779 /*@C
4780    TSComputeRHSFunctionLinear - Evaluate the right hand side via the user-provided Jacobian, for linear problems Udot = A U only
4781 
4782    Collective on TS
4783 
4784    Input Arguments:
4785 +  ts - time stepping context
4786 .  t - time at which to evaluate
4787 .  U - state at which to evaluate
4788 -  ctx - context
4789 
4790    Output Arguments:
4791 .  F - right hand side
4792 
4793    Level: intermediate
4794 
4795    Notes:
4796    This function is intended to be passed to TSSetRHSFunction() to evaluate the right hand side for linear problems.
4797    The matrix (and optionally the evaluation context) should be passed to TSSetRHSJacobian().
4798 
4799 .seealso: TSSetRHSFunction(), TSSetRHSJacobian(), TSComputeRHSJacobianConstant()
4800 @*/
4801 PetscErrorCode TSComputeRHSFunctionLinear(TS ts,PetscReal t,Vec U,Vec F,void *ctx)
4802 {
4803   PetscErrorCode ierr;
4804   Mat            Arhs,Brhs;
4805 
4806   PetscFunctionBegin;
4807   ierr = TSGetRHSMats_Private(ts,&Arhs,&Brhs);CHKERRQ(ierr);
4808   ierr = TSComputeRHSJacobian(ts,t,U,Arhs,Brhs);CHKERRQ(ierr);
4809   ierr = MatMult(Arhs,U,F);CHKERRQ(ierr);
4810   PetscFunctionReturn(0);
4811 }
4812 
4813 /*@C
4814    TSComputeRHSJacobianConstant - Reuses a Jacobian that is time-independent.
4815 
4816    Collective on TS
4817 
4818    Input Arguments:
4819 +  ts - time stepping context
4820 .  t - time at which to evaluate
4821 .  U - state at which to evaluate
4822 -  ctx - context
4823 
4824    Output Arguments:
4825 +  A - pointer to operator
4826 .  B - pointer to preconditioning matrix
4827 -  flg - matrix structure flag
4828 
4829    Level: intermediate
4830 
4831    Notes:
4832    This function is intended to be passed to TSSetRHSJacobian() to evaluate the Jacobian for linear time-independent problems.
4833 
4834 .seealso: TSSetRHSFunction(), TSSetRHSJacobian(), TSComputeRHSFunctionLinear()
4835 @*/
4836 PetscErrorCode TSComputeRHSJacobianConstant(TS ts,PetscReal t,Vec U,Mat A,Mat B,void *ctx)
4837 {
4838   PetscFunctionBegin;
4839   PetscFunctionReturn(0);
4840 }
4841 
4842 /*@C
4843    TSComputeIFunctionLinear - Evaluate the left hand side via the user-provided Jacobian, for linear problems only
4844 
4845    Collective on TS
4846 
4847    Input Arguments:
4848 +  ts - time stepping context
4849 .  t - time at which to evaluate
4850 .  U - state at which to evaluate
4851 .  Udot - time derivative of state vector
4852 -  ctx - context
4853 
4854    Output Arguments:
4855 .  F - left hand side
4856 
4857    Level: intermediate
4858 
4859    Notes:
4860    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
4861    user is required to write their own TSComputeIFunction.
4862    This function is intended to be passed to TSSetIFunction() to evaluate the left hand side for linear problems.
4863    The matrix (and optionally the evaluation context) should be passed to TSSetIJacobian().
4864 
4865    Note that using this function is NOT equivalent to using TSComputeRHSFunctionLinear() since that solves Udot = A U
4866 
4867 .seealso: TSSetIFunction(), TSSetIJacobian(), TSComputeIJacobianConstant(), TSComputeRHSFunctionLinear()
4868 @*/
4869 PetscErrorCode TSComputeIFunctionLinear(TS ts,PetscReal t,Vec U,Vec Udot,Vec F,void *ctx)
4870 {
4871   PetscErrorCode ierr;
4872   Mat            A,B;
4873 
4874   PetscFunctionBegin;
4875   ierr = TSGetIJacobian(ts,&A,&B,NULL,NULL);CHKERRQ(ierr);
4876   ierr = TSComputeIJacobian(ts,t,U,Udot,1.0,A,B,PETSC_TRUE);CHKERRQ(ierr);
4877   ierr = MatMult(A,Udot,F);CHKERRQ(ierr);
4878   PetscFunctionReturn(0);
4879 }
4880 
4881 /*@C
4882    TSComputeIJacobianConstant - Reuses a time-independent for a semi-implicit DAE or ODE
4883 
4884    Collective on TS
4885 
4886    Input Arguments:
4887 +  ts - time stepping context
4888 .  t - time at which to evaluate
4889 .  U - state at which to evaluate
4890 .  Udot - time derivative of state vector
4891 .  shift - shift to apply
4892 -  ctx - context
4893 
4894    Output Arguments:
4895 +  A - pointer to operator
4896 .  B - pointer to preconditioning matrix
4897 -  flg - matrix structure flag
4898 
4899    Level: advanced
4900 
4901    Notes:
4902    This function is intended to be passed to TSSetIJacobian() to evaluate the Jacobian for linear time-independent problems.
4903 
4904    It is only appropriate for problems of the form
4905 
4906 $     M Udot = F(U,t)
4907 
4908   where M is constant and F is non-stiff.  The user must pass M to TSSetIJacobian().  The current implementation only
4909   works with IMEX time integration methods such as TSROSW and TSARKIMEX, since there is no support for de-constructing
4910   an implicit operator of the form
4911 
4912 $    shift*M + J
4913 
4914   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
4915   a copy of M or reassemble it when requested.
4916 
4917 .seealso: TSSetIFunction(), TSSetIJacobian(), TSComputeIFunctionLinear()
4918 @*/
4919 PetscErrorCode TSComputeIJacobianConstant(TS ts,PetscReal t,Vec U,Vec Udot,PetscReal shift,Mat A,Mat B,void *ctx)
4920 {
4921   PetscErrorCode ierr;
4922 
4923   PetscFunctionBegin;
4924   ierr = MatScale(A, shift / ts->ijacobian.shift);CHKERRQ(ierr);
4925   ts->ijacobian.shift = shift;
4926   PetscFunctionReturn(0);
4927 }
4928 
4929 /*@
4930    TSGetEquationType - Gets the type of the equation that TS is solving.
4931 
4932    Not Collective
4933 
4934    Input Parameter:
4935 .  ts - the TS context
4936 
4937    Output Parameter:
4938 .  equation_type - see TSEquationType
4939 
4940    Level: beginner
4941 
4942 .keywords: TS, equation type
4943 
4944 .seealso: TSSetEquationType(), TSEquationType
4945 @*/
4946 PetscErrorCode  TSGetEquationType(TS ts,TSEquationType *equation_type)
4947 {
4948   PetscFunctionBegin;
4949   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4950   PetscValidPointer(equation_type,2);
4951   *equation_type = ts->equation_type;
4952   PetscFunctionReturn(0);
4953 }
4954 
4955 /*@
4956    TSSetEquationType - Sets the type of the equation that TS is solving.
4957 
4958    Not Collective
4959 
4960    Input Parameter:
4961 +  ts - the TS context
4962 -  equation_type - see TSEquationType
4963 
4964    Level: advanced
4965 
4966 .keywords: TS, equation type
4967 
4968 .seealso: TSGetEquationType(), TSEquationType
4969 @*/
4970 PetscErrorCode  TSSetEquationType(TS ts,TSEquationType equation_type)
4971 {
4972   PetscFunctionBegin;
4973   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4974   ts->equation_type = equation_type;
4975   PetscFunctionReturn(0);
4976 }
4977 
4978 /*@
4979    TSGetConvergedReason - Gets the reason the TS iteration was stopped.
4980 
4981    Not Collective
4982 
4983    Input Parameter:
4984 .  ts - the TS context
4985 
4986    Output Parameter:
4987 .  reason - negative value indicates diverged, positive value converged, see TSConvergedReason or the
4988             manual pages for the individual convergence tests for complete lists
4989 
4990    Level: beginner
4991 
4992    Notes:
4993    Can only be called after the call to TSSolve() is complete.
4994 
4995 .keywords: TS, nonlinear, set, convergence, test
4996 
4997 .seealso: TSSetConvergenceTest(), TSConvergedReason
4998 @*/
4999 PetscErrorCode  TSGetConvergedReason(TS ts,TSConvergedReason *reason)
5000 {
5001   PetscFunctionBegin;
5002   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5003   PetscValidPointer(reason,2);
5004   *reason = ts->reason;
5005   PetscFunctionReturn(0);
5006 }
5007 
5008 /*@
5009    TSSetConvergedReason - Sets the reason for handling the convergence of TSSolve.
5010 
5011    Not Collective
5012 
5013    Input Parameter:
5014 +  ts - the TS context
5015 .  reason - negative value indicates diverged, positive value converged, see TSConvergedReason or the
5016             manual pages for the individual convergence tests for complete lists
5017 
5018    Level: advanced
5019 
5020    Notes:
5021    Can only be called during TSSolve() is active.
5022 
5023 .keywords: TS, nonlinear, set, convergence, test
5024 
5025 .seealso: TSConvergedReason
5026 @*/
5027 PetscErrorCode  TSSetConvergedReason(TS ts,TSConvergedReason reason)
5028 {
5029   PetscFunctionBegin;
5030   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5031   ts->reason = reason;
5032   PetscFunctionReturn(0);
5033 }
5034 
5035 /*@
5036    TSGetSolveTime - Gets the time after a call to TSSolve()
5037 
5038    Not Collective
5039 
5040    Input Parameter:
5041 .  ts - the TS context
5042 
5043    Output Parameter:
5044 .  ftime - the final time. This time corresponds to the final time set with TSSetMaxTime()
5045 
5046    Level: beginner
5047 
5048    Notes:
5049    Can only be called after the call to TSSolve() is complete.
5050 
5051 .keywords: TS, nonlinear, set, convergence, test
5052 
5053 .seealso: TSSetConvergenceTest(), TSConvergedReason
5054 @*/
5055 PetscErrorCode  TSGetSolveTime(TS ts,PetscReal *ftime)
5056 {
5057   PetscFunctionBegin;
5058   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5059   PetscValidPointer(ftime,2);
5060   *ftime = ts->solvetime;
5061   PetscFunctionReturn(0);
5062 }
5063 
5064 /*@
5065    TSGetSNESIterations - Gets the total number of nonlinear iterations
5066    used by the time integrator.
5067 
5068    Not Collective
5069 
5070    Input Parameter:
5071 .  ts - TS context
5072 
5073    Output Parameter:
5074 .  nits - number of nonlinear iterations
5075 
5076    Notes:
5077    This counter is reset to zero for each successive call to TSSolve().
5078 
5079    Level: intermediate
5080 
5081 .keywords: TS, get, number, nonlinear, iterations
5082 
5083 .seealso:  TSGetKSPIterations()
5084 @*/
5085 PetscErrorCode TSGetSNESIterations(TS ts,PetscInt *nits)
5086 {
5087   PetscFunctionBegin;
5088   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5089   PetscValidIntPointer(nits,2);
5090   *nits = ts->snes_its;
5091   PetscFunctionReturn(0);
5092 }
5093 
5094 /*@
5095    TSGetKSPIterations - Gets the total number of linear iterations
5096    used by the time integrator.
5097 
5098    Not Collective
5099 
5100    Input Parameter:
5101 .  ts - TS context
5102 
5103    Output Parameter:
5104 .  lits - number of linear iterations
5105 
5106    Notes:
5107    This counter is reset to zero for each successive call to TSSolve().
5108 
5109    Level: intermediate
5110 
5111 .keywords: TS, get, number, linear, iterations
5112 
5113 .seealso:  TSGetSNESIterations(), SNESGetKSPIterations()
5114 @*/
5115 PetscErrorCode TSGetKSPIterations(TS ts,PetscInt *lits)
5116 {
5117   PetscFunctionBegin;
5118   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5119   PetscValidIntPointer(lits,2);
5120   *lits = ts->ksp_its;
5121   PetscFunctionReturn(0);
5122 }
5123 
5124 /*@
5125    TSGetStepRejections - Gets the total number of rejected steps.
5126 
5127    Not Collective
5128 
5129    Input Parameter:
5130 .  ts - TS context
5131 
5132    Output Parameter:
5133 .  rejects - number of steps rejected
5134 
5135    Notes:
5136    This counter is reset to zero for each successive call to TSSolve().
5137 
5138    Level: intermediate
5139 
5140 .keywords: TS, get, number
5141 
5142 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetSNESFailures(), TSSetMaxSNESFailures(), TSSetErrorIfStepFails()
5143 @*/
5144 PetscErrorCode TSGetStepRejections(TS ts,PetscInt *rejects)
5145 {
5146   PetscFunctionBegin;
5147   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5148   PetscValidIntPointer(rejects,2);
5149   *rejects = ts->reject;
5150   PetscFunctionReturn(0);
5151 }
5152 
5153 /*@
5154    TSGetSNESFailures - Gets the total number of failed SNES solves
5155 
5156    Not Collective
5157 
5158    Input Parameter:
5159 .  ts - TS context
5160 
5161    Output Parameter:
5162 .  fails - number of failed nonlinear solves
5163 
5164    Notes:
5165    This counter is reset to zero for each successive call to TSSolve().
5166 
5167    Level: intermediate
5168 
5169 .keywords: TS, get, number
5170 
5171 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetStepRejections(), TSSetMaxSNESFailures()
5172 @*/
5173 PetscErrorCode TSGetSNESFailures(TS ts,PetscInt *fails)
5174 {
5175   PetscFunctionBegin;
5176   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5177   PetscValidIntPointer(fails,2);
5178   *fails = ts->num_snes_failures;
5179   PetscFunctionReturn(0);
5180 }
5181 
5182 /*@
5183    TSSetMaxStepRejections - Sets the maximum number of step rejections before a step fails
5184 
5185    Not Collective
5186 
5187    Input Parameter:
5188 +  ts - TS context
5189 -  rejects - maximum number of rejected steps, pass -1 for unlimited
5190 
5191    Notes:
5192    The counter is reset to zero for each step
5193 
5194    Options Database Key:
5195  .  -ts_max_reject - Maximum number of step rejections before a step fails
5196 
5197    Level: intermediate
5198 
5199 .keywords: TS, set, maximum, number
5200 
5201 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxSNESFailures(), TSGetStepRejections(), TSGetSNESFailures(), TSSetErrorIfStepFails(), TSGetConvergedReason()
5202 @*/
5203 PetscErrorCode TSSetMaxStepRejections(TS ts,PetscInt rejects)
5204 {
5205   PetscFunctionBegin;
5206   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5207   ts->max_reject = rejects;
5208   PetscFunctionReturn(0);
5209 }
5210 
5211 /*@
5212    TSSetMaxSNESFailures - Sets the maximum number of failed SNES solves
5213 
5214    Not Collective
5215 
5216    Input Parameter:
5217 +  ts - TS context
5218 -  fails - maximum number of failed nonlinear solves, pass -1 for unlimited
5219 
5220    Notes:
5221    The counter is reset to zero for each successive call to TSSolve().
5222 
5223    Options Database Key:
5224  .  -ts_max_snes_failures - Maximum number of nonlinear solve failures
5225 
5226    Level: intermediate
5227 
5228 .keywords: TS, set, maximum, number
5229 
5230 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetStepRejections(), TSGetSNESFailures(), SNESGetConvergedReason(), TSGetConvergedReason()
5231 @*/
5232 PetscErrorCode TSSetMaxSNESFailures(TS ts,PetscInt fails)
5233 {
5234   PetscFunctionBegin;
5235   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5236   ts->max_snes_failures = fails;
5237   PetscFunctionReturn(0);
5238 }
5239 
5240 /*@
5241    TSSetErrorIfStepFails - Error if no step succeeds
5242 
5243    Not Collective
5244 
5245    Input Parameter:
5246 +  ts - TS context
5247 -  err - PETSC_TRUE to error if no step succeeds, PETSC_FALSE to return without failure
5248 
5249    Options Database Key:
5250  .  -ts_error_if_step_fails - Error if no step succeeds
5251 
5252    Level: intermediate
5253 
5254 .keywords: TS, set, error
5255 
5256 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetStepRejections(), TSGetSNESFailures(), TSSetErrorIfStepFails(), TSGetConvergedReason()
5257 @*/
5258 PetscErrorCode TSSetErrorIfStepFails(TS ts,PetscBool err)
5259 {
5260   PetscFunctionBegin;
5261   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5262   ts->errorifstepfailed = err;
5263   PetscFunctionReturn(0);
5264 }
5265 
5266 /*@C
5267    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
5268 
5269    Collective on TS
5270 
5271    Input Parameters:
5272 +  ts - the TS context
5273 .  step - current time-step
5274 .  ptime - current time
5275 .  u - current state
5276 -  vf - viewer and its format
5277 
5278    Level: intermediate
5279 
5280 .keywords: TS,  vector, monitor, view
5281 
5282 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
5283 @*/
5284 PetscErrorCode  TSMonitorSolution(TS ts,PetscInt step,PetscReal ptime,Vec u,PetscViewerAndFormat *vf)
5285 {
5286   PetscErrorCode ierr;
5287 
5288   PetscFunctionBegin;
5289   ierr = PetscViewerPushFormat(vf->viewer,vf->format);CHKERRQ(ierr);
5290   ierr = VecView(u,vf->viewer);CHKERRQ(ierr);
5291   ierr = PetscViewerPopFormat(vf->viewer);CHKERRQ(ierr);
5292   PetscFunctionReturn(0);
5293 }
5294 
5295 /*@C
5296    TSMonitorSolutionVTK - Monitors progress of the TS solvers by VecView() for the solution at each timestep.
5297 
5298    Collective on TS
5299 
5300    Input Parameters:
5301 +  ts - the TS context
5302 .  step - current time-step
5303 .  ptime - current time
5304 .  u - current state
5305 -  filenametemplate - string containing a format specifier for the integer time step (e.g. %03D)
5306 
5307    Level: intermediate
5308 
5309    Notes:
5310    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.
5311    These are named according to the file name template.
5312 
5313    This function is normally passed as an argument to TSMonitorSet() along with TSMonitorSolutionVTKDestroy().
5314 
5315 .keywords: TS,  vector, monitor, view
5316 
5317 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
5318 @*/
5319 PetscErrorCode TSMonitorSolutionVTK(TS ts,PetscInt step,PetscReal ptime,Vec u,void *filenametemplate)
5320 {
5321   PetscErrorCode ierr;
5322   char           filename[PETSC_MAX_PATH_LEN];
5323   PetscViewer    viewer;
5324 
5325   PetscFunctionBegin;
5326   if (step < 0) PetscFunctionReturn(0); /* -1 indicates interpolated solution */
5327   ierr = PetscSNPrintf(filename,sizeof(filename),(const char*)filenametemplate,step);CHKERRQ(ierr);
5328   ierr = PetscViewerVTKOpen(PetscObjectComm((PetscObject)ts),filename,FILE_MODE_WRITE,&viewer);CHKERRQ(ierr);
5329   ierr = VecView(u,viewer);CHKERRQ(ierr);
5330   ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
5331   PetscFunctionReturn(0);
5332 }
5333 
5334 /*@C
5335    TSMonitorSolutionVTKDestroy - Destroy context for monitoring
5336 
5337    Collective on TS
5338 
5339    Input Parameters:
5340 .  filenametemplate - string containing a format specifier for the integer time step (e.g. %03D)
5341 
5342    Level: intermediate
5343 
5344    Note:
5345    This function is normally passed to TSMonitorSet() along with TSMonitorSolutionVTK().
5346 
5347 .keywords: TS,  vector, monitor, view
5348 
5349 .seealso: TSMonitorSet(), TSMonitorSolutionVTK()
5350 @*/
5351 PetscErrorCode TSMonitorSolutionVTKDestroy(void *filenametemplate)
5352 {
5353   PetscErrorCode ierr;
5354 
5355   PetscFunctionBegin;
5356   ierr = PetscFree(*(char**)filenametemplate);CHKERRQ(ierr);
5357   PetscFunctionReturn(0);
5358 }
5359 
5360 /*@
5361    TSGetAdapt - Get the adaptive controller context for the current method
5362 
5363    Collective on TS if controller has not been created yet
5364 
5365    Input Arguments:
5366 .  ts - time stepping context
5367 
5368    Output Arguments:
5369 .  adapt - adaptive controller
5370 
5371    Level: intermediate
5372 
5373 .seealso: TSAdapt, TSAdaptSetType(), TSAdaptChoose()
5374 @*/
5375 PetscErrorCode TSGetAdapt(TS ts,TSAdapt *adapt)
5376 {
5377   PetscErrorCode ierr;
5378 
5379   PetscFunctionBegin;
5380   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5381   PetscValidPointer(adapt,2);
5382   if (!ts->adapt) {
5383     ierr = TSAdaptCreate(PetscObjectComm((PetscObject)ts),&ts->adapt);CHKERRQ(ierr);
5384     ierr = PetscLogObjectParent((PetscObject)ts,(PetscObject)ts->adapt);CHKERRQ(ierr);
5385     ierr = PetscObjectIncrementTabLevel((PetscObject)ts->adapt,(PetscObject)ts,1);CHKERRQ(ierr);
5386   }
5387   *adapt = ts->adapt;
5388   PetscFunctionReturn(0);
5389 }
5390 
5391 /*@
5392    TSSetTolerances - Set tolerances for local truncation error when using adaptive controller
5393 
5394    Logically Collective
5395 
5396    Input Arguments:
5397 +  ts - time integration context
5398 .  atol - scalar absolute tolerances, PETSC_DECIDE to leave current value
5399 .  vatol - vector of absolute tolerances or NULL, used in preference to atol if present
5400 .  rtol - scalar relative tolerances, PETSC_DECIDE to leave current value
5401 -  vrtol - vector of relative tolerances or NULL, used in preference to atol if present
5402 
5403    Options Database keys:
5404 +  -ts_rtol <rtol> - relative tolerance for local truncation error
5405 -  -ts_atol <atol> Absolute tolerance for local truncation error
5406 
5407    Notes:
5408    With PETSc's implicit schemes for DAE problems, the calculation of the local truncation error
5409    (LTE) includes both the differential and the algebraic variables. If one wants the LTE to be
5410    computed only for the differential or the algebraic part then this can be done using the vector of
5411    tolerances vatol. For example, by setting the tolerance vector with the desired tolerance for the
5412    differential part and infinity for the algebraic part, the LTE calculation will include only the
5413    differential variables.
5414 
5415    Level: beginner
5416 
5417 .seealso: TS, TSAdapt, TSVecNormWRMS(), TSGetTolerances()
5418 @*/
5419 PetscErrorCode TSSetTolerances(TS ts,PetscReal atol,Vec vatol,PetscReal rtol,Vec vrtol)
5420 {
5421   PetscErrorCode ierr;
5422 
5423   PetscFunctionBegin;
5424   if (atol != PETSC_DECIDE && atol != PETSC_DEFAULT) ts->atol = atol;
5425   if (vatol) {
5426     ierr = PetscObjectReference((PetscObject)vatol);CHKERRQ(ierr);
5427     ierr = VecDestroy(&ts->vatol);CHKERRQ(ierr);
5428     ts->vatol = vatol;
5429   }
5430   if (rtol != PETSC_DECIDE && rtol != PETSC_DEFAULT) ts->rtol = rtol;
5431   if (vrtol) {
5432     ierr = PetscObjectReference((PetscObject)vrtol);CHKERRQ(ierr);
5433     ierr = VecDestroy(&ts->vrtol);CHKERRQ(ierr);
5434     ts->vrtol = vrtol;
5435   }
5436   PetscFunctionReturn(0);
5437 }
5438 
5439 /*@
5440    TSGetTolerances - Get tolerances for local truncation error when using adaptive controller
5441 
5442    Logically Collective
5443 
5444    Input Arguments:
5445 .  ts - time integration context
5446 
5447    Output Arguments:
5448 +  atol - scalar absolute tolerances, NULL to ignore
5449 .  vatol - vector of absolute tolerances, NULL to ignore
5450 .  rtol - scalar relative tolerances, NULL to ignore
5451 -  vrtol - vector of relative tolerances, NULL to ignore
5452 
5453    Level: beginner
5454 
5455 .seealso: TS, TSAdapt, TSVecNormWRMS(), TSSetTolerances()
5456 @*/
5457 PetscErrorCode TSGetTolerances(TS ts,PetscReal *atol,Vec *vatol,PetscReal *rtol,Vec *vrtol)
5458 {
5459   PetscFunctionBegin;
5460   if (atol)  *atol  = ts->atol;
5461   if (vatol) *vatol = ts->vatol;
5462   if (rtol)  *rtol  = ts->rtol;
5463   if (vrtol) *vrtol = ts->vrtol;
5464   PetscFunctionReturn(0);
5465 }
5466 
5467 /*@
5468    TSErrorWeightedNorm2 - compute a weighted 2-norm of the difference between two state vectors
5469 
5470    Collective on TS
5471 
5472    Input Arguments:
5473 +  ts - time stepping context
5474 .  U - state vector, usually ts->vec_sol
5475 -  Y - state vector to be compared to U
5476 
5477    Output Arguments:
5478 .  norm - weighted norm, a value of 1.0 means that the error matches the tolerances
5479 .  norma - weighted norm based on the absolute tolerance, a value of 1.0 means that the error matches the tolerances
5480 .  normr - weighted norm based on the relative tolerance, a value of 1.0 means that the error matches the tolerances
5481 
5482    Level: developer
5483 
5484 .seealso: TSErrorWeightedNorm(), TSErrorWeightedNormInfinity()
5485 @*/
5486 PetscErrorCode TSErrorWeightedNorm2(TS ts,Vec U,Vec Y,PetscReal *norm,PetscReal *norma,PetscReal *normr)
5487 {
5488   PetscErrorCode    ierr;
5489   PetscInt          i,n,N,rstart;
5490   PetscInt          n_loc,na_loc,nr_loc;
5491   PetscReal         n_glb,na_glb,nr_glb;
5492   const PetscScalar *u,*y;
5493   PetscReal         sum,suma,sumr,gsum,gsuma,gsumr,diff;
5494   PetscReal         tol,tola,tolr;
5495   PetscReal         err_loc[6],err_glb[6];
5496 
5497   PetscFunctionBegin;
5498   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5499   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
5500   PetscValidHeaderSpecific(Y,VEC_CLASSID,3);
5501   PetscValidType(U,2);
5502   PetscValidType(Y,3);
5503   PetscCheckSameComm(U,2,Y,3);
5504   PetscValidPointer(norm,4);
5505   PetscValidPointer(norma,5);
5506   PetscValidPointer(normr,6);
5507   if (U == Y) SETERRQ(PetscObjectComm((PetscObject)U),PETSC_ERR_ARG_IDN,"U and Y cannot be the same vector");
5508 
5509   ierr = VecGetSize(U,&N);CHKERRQ(ierr);
5510   ierr = VecGetLocalSize(U,&n);CHKERRQ(ierr);
5511   ierr = VecGetOwnershipRange(U,&rstart,NULL);CHKERRQ(ierr);
5512   ierr = VecGetArrayRead(U,&u);CHKERRQ(ierr);
5513   ierr = VecGetArrayRead(Y,&y);CHKERRQ(ierr);
5514   sum  = 0.; n_loc  = 0;
5515   suma = 0.; na_loc = 0;
5516   sumr = 0.; nr_loc = 0;
5517   if (ts->vatol && ts->vrtol) {
5518     const PetscScalar *atol,*rtol;
5519     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5520     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5521     for (i=0; i<n; i++) {
5522       diff = PetscAbsScalar(y[i] - u[i]);
5523       tola = PetscRealPart(atol[i]);
5524       if(tola>0.){
5525         suma  += PetscSqr(diff/tola);
5526         na_loc++;
5527       }
5528       tolr = PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5529       if(tolr>0.){
5530         sumr  += PetscSqr(diff/tolr);
5531         nr_loc++;
5532       }
5533       tol=tola+tolr;
5534       if(tol>0.){
5535         sum  += PetscSqr(diff/tol);
5536         n_loc++;
5537       }
5538     }
5539     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5540     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5541   } else if (ts->vatol) {       /* vector atol, scalar rtol */
5542     const PetscScalar *atol;
5543     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5544     for (i=0; i<n; i++) {
5545       diff = PetscAbsScalar(y[i] - u[i]);
5546       tola = PetscRealPart(atol[i]);
5547       if(tola>0.){
5548         suma  += PetscSqr(diff/tola);
5549         na_loc++;
5550       }
5551       tolr = ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5552       if(tolr>0.){
5553         sumr  += PetscSqr(diff/tolr);
5554         nr_loc++;
5555       }
5556       tol=tola+tolr;
5557       if(tol>0.){
5558         sum  += PetscSqr(diff/tol);
5559         n_loc++;
5560       }
5561     }
5562     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5563   } else if (ts->vrtol) {       /* scalar atol, vector rtol */
5564     const PetscScalar *rtol;
5565     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5566     for (i=0; i<n; i++) {
5567       diff = PetscAbsScalar(y[i] - u[i]);
5568       tola = ts->atol;
5569       if(tola>0.){
5570         suma  += PetscSqr(diff/tola);
5571         na_loc++;
5572       }
5573       tolr = PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5574       if(tolr>0.){
5575         sumr  += PetscSqr(diff/tolr);
5576         nr_loc++;
5577       }
5578       tol=tola+tolr;
5579       if(tol>0.){
5580         sum  += PetscSqr(diff/tol);
5581         n_loc++;
5582       }
5583     }
5584     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5585   } else {                      /* scalar atol, scalar rtol */
5586     for (i=0; i<n; i++) {
5587       diff = PetscAbsScalar(y[i] - u[i]);
5588      tola = ts->atol;
5589       if(tola>0.){
5590         suma  += PetscSqr(diff/tola);
5591         na_loc++;
5592       }
5593       tolr = ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5594       if(tolr>0.){
5595         sumr  += PetscSqr(diff/tolr);
5596         nr_loc++;
5597       }
5598       tol=tola+tolr;
5599       if(tol>0.){
5600         sum  += PetscSqr(diff/tol);
5601         n_loc++;
5602       }
5603     }
5604   }
5605   ierr = VecRestoreArrayRead(U,&u);CHKERRQ(ierr);
5606   ierr = VecRestoreArrayRead(Y,&y);CHKERRQ(ierr);
5607 
5608   err_loc[0] = sum;
5609   err_loc[1] = suma;
5610   err_loc[2] = sumr;
5611   err_loc[3] = (PetscReal)n_loc;
5612   err_loc[4] = (PetscReal)na_loc;
5613   err_loc[5] = (PetscReal)nr_loc;
5614 
5615   ierr = MPIU_Allreduce(err_loc,err_glb,6,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
5616 
5617   gsum   = err_glb[0];
5618   gsuma  = err_glb[1];
5619   gsumr  = err_glb[2];
5620   n_glb  = err_glb[3];
5621   na_glb = err_glb[4];
5622   nr_glb = err_glb[5];
5623 
5624   *norm  = 0.;
5625   if(n_glb>0. ){*norm  = PetscSqrtReal(gsum  / n_glb );}
5626   *norma = 0.;
5627   if(na_glb>0.){*norma = PetscSqrtReal(gsuma / na_glb);}
5628   *normr = 0.;
5629   if(nr_glb>0.){*normr = PetscSqrtReal(gsumr / nr_glb);}
5630 
5631   if (PetscIsInfOrNanScalar(*norm)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
5632   if (PetscIsInfOrNanScalar(*norma)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norma");
5633   if (PetscIsInfOrNanScalar(*normr)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in normr");
5634   PetscFunctionReturn(0);
5635 }
5636 
5637 /*@
5638    TSErrorWeightedNormInfinity - compute a weighted infinity-norm of the difference between two state vectors
5639 
5640    Collective on TS
5641 
5642    Input Arguments:
5643 +  ts - time stepping context
5644 .  U - state vector, usually ts->vec_sol
5645 -  Y - state vector to be compared to U
5646 
5647    Output Arguments:
5648 .  norm - weighted norm, a value of 1.0 means that the error matches the tolerances
5649 .  norma - weighted norm based on the absolute tolerance, a value of 1.0 means that the error matches the tolerances
5650 .  normr - weighted norm based on the relative tolerance, a value of 1.0 means that the error matches the tolerances
5651 
5652    Level: developer
5653 
5654 .seealso: TSErrorWeightedNorm(), TSErrorWeightedNorm2()
5655 @*/
5656 PetscErrorCode TSErrorWeightedNormInfinity(TS ts,Vec U,Vec Y,PetscReal *norm,PetscReal *norma,PetscReal *normr)
5657 {
5658   PetscErrorCode    ierr;
5659   PetscInt          i,n,N,rstart;
5660   const PetscScalar *u,*y;
5661   PetscReal         max,gmax,maxa,gmaxa,maxr,gmaxr;
5662   PetscReal         tol,tola,tolr,diff;
5663   PetscReal         err_loc[3],err_glb[3];
5664 
5665   PetscFunctionBegin;
5666   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5667   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
5668   PetscValidHeaderSpecific(Y,VEC_CLASSID,3);
5669   PetscValidType(U,2);
5670   PetscValidType(Y,3);
5671   PetscCheckSameComm(U,2,Y,3);
5672   PetscValidPointer(norm,4);
5673   PetscValidPointer(norma,5);
5674   PetscValidPointer(normr,6);
5675   if (U == Y) SETERRQ(PetscObjectComm((PetscObject)U),PETSC_ERR_ARG_IDN,"U and Y cannot be the same vector");
5676 
5677   ierr = VecGetSize(U,&N);CHKERRQ(ierr);
5678   ierr = VecGetLocalSize(U,&n);CHKERRQ(ierr);
5679   ierr = VecGetOwnershipRange(U,&rstart,NULL);CHKERRQ(ierr);
5680   ierr = VecGetArrayRead(U,&u);CHKERRQ(ierr);
5681   ierr = VecGetArrayRead(Y,&y);CHKERRQ(ierr);
5682 
5683   max=0.;
5684   maxa=0.;
5685   maxr=0.;
5686 
5687   if (ts->vatol && ts->vrtol) {     /* vector atol, vector rtol */
5688     const PetscScalar *atol,*rtol;
5689     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5690     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5691 
5692     for (i=0; i<n; i++) {
5693       diff = PetscAbsScalar(y[i] - u[i]);
5694       tola = PetscRealPart(atol[i]);
5695       tolr = PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5696       tol  = tola+tolr;
5697       if(tola>0.){
5698         maxa = PetscMax(maxa,diff / tola);
5699       }
5700       if(tolr>0.){
5701         maxr = PetscMax(maxr,diff / tolr);
5702       }
5703       if(tol>0.){
5704         max = PetscMax(max,diff / tol);
5705       }
5706     }
5707     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5708     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5709   } else if (ts->vatol) {       /* vector atol, scalar rtol */
5710     const PetscScalar *atol;
5711     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5712     for (i=0; i<n; i++) {
5713       diff = PetscAbsScalar(y[i] - u[i]);
5714       tola = PetscRealPart(atol[i]);
5715       tolr = ts->rtol  * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5716       tol  = tola+tolr;
5717       if(tola>0.){
5718         maxa = PetscMax(maxa,diff / tola);
5719       }
5720       if(tolr>0.){
5721         maxr = PetscMax(maxr,diff / tolr);
5722       }
5723       if(tol>0.){
5724         max = PetscMax(max,diff / tol);
5725       }
5726     }
5727     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5728   } else if (ts->vrtol) {       /* scalar atol, vector rtol */
5729     const PetscScalar *rtol;
5730     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5731 
5732     for (i=0; i<n; i++) {
5733       diff = PetscAbsScalar(y[i] - u[i]);
5734       tola = ts->atol;
5735       tolr = PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5736       tol  = tola+tolr;
5737       if(tola>0.){
5738         maxa = PetscMax(maxa,diff / tola);
5739       }
5740       if(tolr>0.){
5741         maxr = PetscMax(maxr,diff / tolr);
5742       }
5743       if(tol>0.){
5744         max = PetscMax(max,diff / tol);
5745       }
5746     }
5747     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5748   } else {                      /* scalar atol, scalar rtol */
5749 
5750     for (i=0; i<n; i++) {
5751       diff = PetscAbsScalar(y[i] - u[i]);
5752       tola = ts->atol;
5753       tolr = ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5754       tol  = tola+tolr;
5755       if(tola>0.){
5756         maxa = PetscMax(maxa,diff / tola);
5757       }
5758       if(tolr>0.){
5759         maxr = PetscMax(maxr,diff / tolr);
5760       }
5761       if(tol>0.){
5762         max = PetscMax(max,diff / tol);
5763       }
5764     }
5765   }
5766   ierr = VecRestoreArrayRead(U,&u);CHKERRQ(ierr);
5767   ierr = VecRestoreArrayRead(Y,&y);CHKERRQ(ierr);
5768   err_loc[0] = max;
5769   err_loc[1] = maxa;
5770   err_loc[2] = maxr;
5771   ierr  = MPIU_Allreduce(err_loc,err_glb,3,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
5772   gmax   = err_glb[0];
5773   gmaxa  = err_glb[1];
5774   gmaxr  = err_glb[2];
5775 
5776   *norm = gmax;
5777   *norma = gmaxa;
5778   *normr = gmaxr;
5779   if (PetscIsInfOrNanScalar(*norm)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
5780     if (PetscIsInfOrNanScalar(*norma)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norma");
5781     if (PetscIsInfOrNanScalar(*normr)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in normr");
5782   PetscFunctionReturn(0);
5783 }
5784 
5785 /*@
5786    TSErrorWeightedNorm - compute a weighted norm of the difference between two state vectors based on supplied absolute and relative tolerances
5787 
5788    Collective on TS
5789 
5790    Input Arguments:
5791 +  ts - time stepping context
5792 .  U - state vector, usually ts->vec_sol
5793 .  Y - state vector to be compared to U
5794 -  wnormtype - norm type, either NORM_2 or NORM_INFINITY
5795 
5796    Output Arguments:
5797 .  norm  - weighted norm, a value of 1.0 achieves a balance between absolute and relative tolerances
5798 .  norma - weighted norm, a value of 1.0 means that the error meets the absolute tolerance set by the user
5799 .  normr - weighted norm, a value of 1.0 means that the error meets the relative tolerance set by the user
5800 
5801    Options Database Keys:
5802 .  -ts_adapt_wnormtype <wnormtype> - 2, INFINITY
5803 
5804    Level: developer
5805 
5806 .seealso: TSErrorWeightedNormInfinity(), TSErrorWeightedNorm2(), TSErrorWeightedENorm
5807 @*/
5808 PetscErrorCode TSErrorWeightedNorm(TS ts,Vec U,Vec Y,NormType wnormtype,PetscReal *norm,PetscReal *norma,PetscReal *normr)
5809 {
5810   PetscErrorCode ierr;
5811 
5812   PetscFunctionBegin;
5813   if (wnormtype == NORM_2) {
5814     ierr = TSErrorWeightedNorm2(ts,U,Y,norm,norma,normr);CHKERRQ(ierr);
5815   } else if(wnormtype == NORM_INFINITY) {
5816     ierr = TSErrorWeightedNormInfinity(ts,U,Y,norm,norma,normr);CHKERRQ(ierr);
5817   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support for norm type %s",NormTypes[wnormtype]);
5818   PetscFunctionReturn(0);
5819 }
5820 
5821 
5822 /*@
5823    TSErrorWeightedENorm2 - compute a weighted 2 error norm based on supplied absolute and relative tolerances
5824 
5825    Collective on TS
5826 
5827    Input Arguments:
5828 +  ts - time stepping context
5829 .  E - error vector
5830 .  U - state vector, usually ts->vec_sol
5831 -  Y - state vector, previous time step
5832 
5833    Output Arguments:
5834 .  norm - weighted norm, a value of 1.0 means that the error matches the tolerances
5835 .  norma - weighted norm based on the absolute tolerance, a value of 1.0 means that the error matches the tolerances
5836 .  normr - weighted norm based on the relative tolerance, a value of 1.0 means that the error matches the tolerances
5837 
5838    Level: developer
5839 
5840 .seealso: TSErrorWeightedENorm(), TSErrorWeightedENormInfinity()
5841 @*/
5842 PetscErrorCode TSErrorWeightedENorm2(TS ts,Vec E,Vec U,Vec Y,PetscReal *norm,PetscReal *norma,PetscReal *normr)
5843 {
5844   PetscErrorCode    ierr;
5845   PetscInt          i,n,N,rstart;
5846   PetscInt          n_loc,na_loc,nr_loc;
5847   PetscReal         n_glb,na_glb,nr_glb;
5848   const PetscScalar *e,*u,*y;
5849   PetscReal         err,sum,suma,sumr,gsum,gsuma,gsumr;
5850   PetscReal         tol,tola,tolr;
5851   PetscReal         err_loc[6],err_glb[6];
5852 
5853   PetscFunctionBegin;
5854   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
5855   PetscValidHeaderSpecific(E,VEC_CLASSID,2);
5856   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
5857   PetscValidHeaderSpecific(Y,VEC_CLASSID,4);
5858   PetscValidType(E,2);
5859   PetscValidType(U,3);
5860   PetscValidType(Y,4);
5861   PetscCheckSameComm(E,2,U,3);
5862   PetscCheckSameComm(U,2,Y,3);
5863   PetscValidPointer(norm,5);
5864   PetscValidPointer(norma,6);
5865   PetscValidPointer(normr,7);
5866 
5867   ierr = VecGetSize(E,&N);CHKERRQ(ierr);
5868   ierr = VecGetLocalSize(E,&n);CHKERRQ(ierr);
5869   ierr = VecGetOwnershipRange(E,&rstart,NULL);CHKERRQ(ierr);
5870   ierr = VecGetArrayRead(E,&e);CHKERRQ(ierr);
5871   ierr = VecGetArrayRead(U,&u);CHKERRQ(ierr);
5872   ierr = VecGetArrayRead(Y,&y);CHKERRQ(ierr);
5873   sum  = 0.; n_loc  = 0;
5874   suma = 0.; na_loc = 0;
5875   sumr = 0.; nr_loc = 0;
5876   if (ts->vatol && ts->vrtol) {
5877     const PetscScalar *atol,*rtol;
5878     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5879     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5880     for (i=0; i<n; i++) {
5881       err = PetscAbsScalar(e[i]);
5882       tola = PetscRealPart(atol[i]);
5883       if(tola>0.){
5884         suma  += PetscSqr(err/tola);
5885         na_loc++;
5886       }
5887       tolr = PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5888       if(tolr>0.){
5889         sumr  += PetscSqr(err/tolr);
5890         nr_loc++;
5891       }
5892       tol=tola+tolr;
5893       if(tol>0.){
5894         sum  += PetscSqr(err/tol);
5895         n_loc++;
5896       }
5897     }
5898     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5899     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5900   } else if (ts->vatol) {       /* vector atol, scalar rtol */
5901     const PetscScalar *atol;
5902     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5903     for (i=0; i<n; i++) {
5904       err = PetscAbsScalar(e[i]);
5905       tola = PetscRealPart(atol[i]);
5906       if(tola>0.){
5907         suma  += PetscSqr(err/tola);
5908         na_loc++;
5909       }
5910       tolr = ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5911       if(tolr>0.){
5912         sumr  += PetscSqr(err/tolr);
5913         nr_loc++;
5914       }
5915       tol=tola+tolr;
5916       if(tol>0.){
5917         sum  += PetscSqr(err/tol);
5918         n_loc++;
5919       }
5920     }
5921     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
5922   } else if (ts->vrtol) {       /* scalar atol, vector rtol */
5923     const PetscScalar *rtol;
5924     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5925     for (i=0; i<n; i++) {
5926       err = PetscAbsScalar(e[i]);
5927       tola = ts->atol;
5928       if(tola>0.){
5929         suma  += PetscSqr(err/tola);
5930         na_loc++;
5931       }
5932       tolr = PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5933       if(tolr>0.){
5934         sumr  += PetscSqr(err/tolr);
5935         nr_loc++;
5936       }
5937       tol=tola+tolr;
5938       if(tol>0.){
5939         sum  += PetscSqr(err/tol);
5940         n_loc++;
5941       }
5942     }
5943     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
5944   } else {                      /* scalar atol, scalar rtol */
5945     for (i=0; i<n; i++) {
5946       err = PetscAbsScalar(e[i]);
5947      tola = ts->atol;
5948       if(tola>0.){
5949         suma  += PetscSqr(err/tola);
5950         na_loc++;
5951       }
5952       tolr = ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
5953       if(tolr>0.){
5954         sumr  += PetscSqr(err/tolr);
5955         nr_loc++;
5956       }
5957       tol=tola+tolr;
5958       if(tol>0.){
5959         sum  += PetscSqr(err/tol);
5960         n_loc++;
5961       }
5962     }
5963   }
5964   ierr = VecRestoreArrayRead(E,&e);CHKERRQ(ierr);
5965   ierr = VecRestoreArrayRead(U,&u);CHKERRQ(ierr);
5966   ierr = VecRestoreArrayRead(Y,&y);CHKERRQ(ierr);
5967 
5968   err_loc[0] = sum;
5969   err_loc[1] = suma;
5970   err_loc[2] = sumr;
5971   err_loc[3] = (PetscReal)n_loc;
5972   err_loc[4] = (PetscReal)na_loc;
5973   err_loc[5] = (PetscReal)nr_loc;
5974 
5975   ierr = MPIU_Allreduce(err_loc,err_glb,6,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
5976 
5977   gsum   = err_glb[0];
5978   gsuma  = err_glb[1];
5979   gsumr  = err_glb[2];
5980   n_glb  = err_glb[3];
5981   na_glb = err_glb[4];
5982   nr_glb = err_glb[5];
5983 
5984   *norm  = 0.;
5985   if(n_glb>0. ){*norm  = PetscSqrtReal(gsum  / n_glb );}
5986   *norma = 0.;
5987   if(na_glb>0.){*norma = PetscSqrtReal(gsuma / na_glb);}
5988   *normr = 0.;
5989   if(nr_glb>0.){*normr = PetscSqrtReal(gsumr / nr_glb);}
5990 
5991   if (PetscIsInfOrNanScalar(*norm)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
5992   if (PetscIsInfOrNanScalar(*norma)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norma");
5993   if (PetscIsInfOrNanScalar(*normr)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in normr");
5994   PetscFunctionReturn(0);
5995 }
5996 
5997 /*@
5998    TSErrorWeightedENormInfinity - compute a weighted infinity error norm based on supplied absolute and relative tolerances
5999    Collective on TS
6000 
6001    Input Arguments:
6002 +  ts - time stepping context
6003 .  E - error vector
6004 .  U - state vector, usually ts->vec_sol
6005 -  Y - state vector, previous time step
6006 
6007    Output Arguments:
6008 .  norm - weighted norm, a value of 1.0 means that the error matches the tolerances
6009 .  norma - weighted norm based on the absolute tolerance, a value of 1.0 means that the error matches the tolerances
6010 .  normr - weighted norm based on the relative tolerance, a value of 1.0 means that the error matches the tolerances
6011 
6012    Level: developer
6013 
6014 .seealso: TSErrorWeightedENorm(), TSErrorWeightedENorm2()
6015 @*/
6016 PetscErrorCode TSErrorWeightedENormInfinity(TS ts,Vec E,Vec U,Vec Y,PetscReal *norm,PetscReal *norma,PetscReal *normr)
6017 {
6018   PetscErrorCode    ierr;
6019   PetscInt          i,n,N,rstart;
6020   const PetscScalar *e,*u,*y;
6021   PetscReal         err,max,gmax,maxa,gmaxa,maxr,gmaxr;
6022   PetscReal         tol,tola,tolr;
6023   PetscReal         err_loc[3],err_glb[3];
6024 
6025   PetscFunctionBegin;
6026   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
6027   PetscValidHeaderSpecific(E,VEC_CLASSID,2);
6028   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
6029   PetscValidHeaderSpecific(Y,VEC_CLASSID,4);
6030   PetscValidType(E,2);
6031   PetscValidType(U,3);
6032   PetscValidType(Y,4);
6033   PetscCheckSameComm(E,2,U,3);
6034   PetscCheckSameComm(U,2,Y,3);
6035   PetscValidPointer(norm,5);
6036   PetscValidPointer(norma,6);
6037   PetscValidPointer(normr,7);
6038 
6039   ierr = VecGetSize(E,&N);CHKERRQ(ierr);
6040   ierr = VecGetLocalSize(E,&n);CHKERRQ(ierr);
6041   ierr = VecGetOwnershipRange(E,&rstart,NULL);CHKERRQ(ierr);
6042   ierr = VecGetArrayRead(E,&e);CHKERRQ(ierr);
6043   ierr = VecGetArrayRead(U,&u);CHKERRQ(ierr);
6044   ierr = VecGetArrayRead(Y,&y);CHKERRQ(ierr);
6045 
6046   max=0.;
6047   maxa=0.;
6048   maxr=0.;
6049 
6050   if (ts->vatol && ts->vrtol) {     /* vector atol, vector rtol */
6051     const PetscScalar *atol,*rtol;
6052     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
6053     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
6054 
6055     for (i=0; i<n; i++) {
6056       err = PetscAbsScalar(e[i]);
6057       tola = PetscRealPart(atol[i]);
6058       tolr = PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
6059       tol  = tola+tolr;
6060       if(tola>0.){
6061         maxa = PetscMax(maxa,err / tola);
6062       }
6063       if(tolr>0.){
6064         maxr = PetscMax(maxr,err / tolr);
6065       }
6066       if(tol>0.){
6067         max = PetscMax(max,err / tol);
6068       }
6069     }
6070     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
6071     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
6072   } else if (ts->vatol) {       /* vector atol, scalar rtol */
6073     const PetscScalar *atol;
6074     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
6075     for (i=0; i<n; i++) {
6076       err = PetscAbsScalar(e[i]);
6077       tola = PetscRealPart(atol[i]);
6078       tolr = ts->rtol  * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
6079       tol  = tola+tolr;
6080       if(tola>0.){
6081         maxa = PetscMax(maxa,err / tola);
6082       }
6083       if(tolr>0.){
6084         maxr = PetscMax(maxr,err / tolr);
6085       }
6086       if(tol>0.){
6087         max = PetscMax(max,err / tol);
6088       }
6089     }
6090     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
6091   } else if (ts->vrtol) {       /* scalar atol, vector rtol */
6092     const PetscScalar *rtol;
6093     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
6094 
6095     for (i=0; i<n; i++) {
6096       err = PetscAbsScalar(e[i]);
6097       tola = ts->atol;
6098       tolr = PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
6099       tol  = tola+tolr;
6100       if(tola>0.){
6101         maxa = PetscMax(maxa,err / tola);
6102       }
6103       if(tolr>0.){
6104         maxr = PetscMax(maxr,err / tolr);
6105       }
6106       if(tol>0.){
6107         max = PetscMax(max,err / tol);
6108       }
6109     }
6110     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
6111   } else {                      /* scalar atol, scalar rtol */
6112 
6113     for (i=0; i<n; i++) {
6114       err = PetscAbsScalar(e[i]);
6115       tola = ts->atol;
6116       tolr = ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
6117       tol  = tola+tolr;
6118       if(tola>0.){
6119         maxa = PetscMax(maxa,err / tola);
6120       }
6121       if(tolr>0.){
6122         maxr = PetscMax(maxr,err / tolr);
6123       }
6124       if(tol>0.){
6125         max = PetscMax(max,err / tol);
6126       }
6127     }
6128   }
6129   ierr = VecRestoreArrayRead(E,&e);CHKERRQ(ierr);
6130   ierr = VecRestoreArrayRead(U,&u);CHKERRQ(ierr);
6131   ierr = VecRestoreArrayRead(Y,&y);CHKERRQ(ierr);
6132   err_loc[0] = max;
6133   err_loc[1] = maxa;
6134   err_loc[2] = maxr;
6135   ierr  = MPIU_Allreduce(err_loc,err_glb,3,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
6136   gmax   = err_glb[0];
6137   gmaxa  = err_glb[1];
6138   gmaxr  = err_glb[2];
6139 
6140   *norm = gmax;
6141   *norma = gmaxa;
6142   *normr = gmaxr;
6143   if (PetscIsInfOrNanScalar(*norm)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
6144     if (PetscIsInfOrNanScalar(*norma)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norma");
6145     if (PetscIsInfOrNanScalar(*normr)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in normr");
6146   PetscFunctionReturn(0);
6147 }
6148 
6149 /*@
6150    TSErrorWeightedENorm - compute a weighted error norm based on supplied absolute and relative tolerances
6151 
6152    Collective on TS
6153 
6154    Input Arguments:
6155 +  ts - time stepping context
6156 .  E - error vector
6157 .  U - state vector, usually ts->vec_sol
6158 .  Y - state vector, previous time step
6159 -  wnormtype - norm type, either NORM_2 or NORM_INFINITY
6160 
6161    Output Arguments:
6162 .  norm  - weighted norm, a value of 1.0 achieves a balance between absolute and relative tolerances
6163 .  norma - weighted norm, a value of 1.0 means that the error meets the absolute tolerance set by the user
6164 .  normr - weighted norm, a value of 1.0 means that the error meets the relative tolerance set by the user
6165 
6166    Options Database Keys:
6167 .  -ts_adapt_wnormtype <wnormtype> - 2, INFINITY
6168 
6169    Level: developer
6170 
6171 .seealso: TSErrorWeightedENormInfinity(), TSErrorWeightedENorm2(), TSErrorWeightedNormInfinity(), TSErrorWeightedNorm2()
6172 @*/
6173 PetscErrorCode TSErrorWeightedENorm(TS ts,Vec E,Vec U,Vec Y,NormType wnormtype,PetscReal *norm,PetscReal *norma,PetscReal *normr)
6174 {
6175   PetscErrorCode ierr;
6176 
6177   PetscFunctionBegin;
6178   if (wnormtype == NORM_2) {
6179     ierr = TSErrorWeightedENorm2(ts,E,U,Y,norm,norma,normr);CHKERRQ(ierr);
6180   } else if(wnormtype == NORM_INFINITY) {
6181     ierr = TSErrorWeightedENormInfinity(ts,E,U,Y,norm,norma,normr);CHKERRQ(ierr);
6182   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support for norm type %s",NormTypes[wnormtype]);
6183   PetscFunctionReturn(0);
6184 }
6185 
6186 
6187 /*@
6188    TSSetCFLTimeLocal - Set the local CFL constraint relative to forward Euler
6189 
6190    Logically Collective on TS
6191 
6192    Input Arguments:
6193 +  ts - time stepping context
6194 -  cfltime - maximum stable time step if using forward Euler (value can be different on each process)
6195 
6196    Note:
6197    After calling this function, the global CFL time can be obtained by calling TSGetCFLTime()
6198 
6199    Level: intermediate
6200 
6201 .seealso: TSGetCFLTime(), TSADAPTCFL
6202 @*/
6203 PetscErrorCode TSSetCFLTimeLocal(TS ts,PetscReal cfltime)
6204 {
6205   PetscFunctionBegin;
6206   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
6207   ts->cfltime_local = cfltime;
6208   ts->cfltime       = -1.;
6209   PetscFunctionReturn(0);
6210 }
6211 
6212 /*@
6213    TSGetCFLTime - Get the maximum stable time step according to CFL criteria applied to forward Euler
6214 
6215    Collective on TS
6216 
6217    Input Arguments:
6218 .  ts - time stepping context
6219 
6220    Output Arguments:
6221 .  cfltime - maximum stable time step for forward Euler
6222 
6223    Level: advanced
6224 
6225 .seealso: TSSetCFLTimeLocal()
6226 @*/
6227 PetscErrorCode TSGetCFLTime(TS ts,PetscReal *cfltime)
6228 {
6229   PetscErrorCode ierr;
6230 
6231   PetscFunctionBegin;
6232   if (ts->cfltime < 0) {
6233     ierr = MPIU_Allreduce(&ts->cfltime_local,&ts->cfltime,1,MPIU_REAL,MPIU_MIN,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
6234   }
6235   *cfltime = ts->cfltime;
6236   PetscFunctionReturn(0);
6237 }
6238 
6239 /*@
6240    TSVISetVariableBounds - Sets the lower and upper bounds for the solution vector. xl <= x <= xu
6241 
6242    Input Parameters:
6243 .  ts   - the TS context.
6244 .  xl   - lower bound.
6245 .  xu   - upper bound.
6246 
6247    Notes:
6248    If this routine is not called then the lower and upper bounds are set to
6249    PETSC_NINFINITY and PETSC_INFINITY respectively during SNESSetUp().
6250 
6251    Level: advanced
6252 
6253 @*/
6254 PetscErrorCode TSVISetVariableBounds(TS ts, Vec xl, Vec xu)
6255 {
6256   PetscErrorCode ierr;
6257   SNES           snes;
6258 
6259   PetscFunctionBegin;
6260   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
6261   ierr = SNESVISetVariableBounds(snes,xl,xu);CHKERRQ(ierr);
6262   PetscFunctionReturn(0);
6263 }
6264 
6265 #if defined(PETSC_HAVE_MATLAB_ENGINE)
6266 #include <mex.h>
6267 
6268 typedef struct {char *funcname; mxArray *ctx;} TSMatlabContext;
6269 
6270 /*
6271    TSComputeFunction_Matlab - Calls the function that has been set with
6272                          TSSetFunctionMatlab().
6273 
6274    Collective on TS
6275 
6276    Input Parameters:
6277 +  snes - the TS context
6278 -  u - input vector
6279 
6280    Output Parameter:
6281 .  y - function vector, as set by TSSetFunction()
6282 
6283    Notes:
6284    TSComputeFunction() is typically used within nonlinear solvers
6285    implementations, so most users would not generally call this routine
6286    themselves.
6287 
6288    Level: developer
6289 
6290 .keywords: TS, nonlinear, compute, function
6291 
6292 .seealso: TSSetFunction(), TSGetFunction()
6293 */
6294 PetscErrorCode  TSComputeFunction_Matlab(TS snes,PetscReal time,Vec u,Vec udot,Vec y, void *ctx)
6295 {
6296   PetscErrorCode  ierr;
6297   TSMatlabContext *sctx = (TSMatlabContext*)ctx;
6298   int             nlhs  = 1,nrhs = 7;
6299   mxArray         *plhs[1],*prhs[7];
6300   long long int   lx = 0,lxdot = 0,ly = 0,ls = 0;
6301 
6302   PetscFunctionBegin;
6303   PetscValidHeaderSpecific(snes,TS_CLASSID,1);
6304   PetscValidHeaderSpecific(u,VEC_CLASSID,3);
6305   PetscValidHeaderSpecific(udot,VEC_CLASSID,4);
6306   PetscValidHeaderSpecific(y,VEC_CLASSID,5);
6307   PetscCheckSameComm(snes,1,u,3);
6308   PetscCheckSameComm(snes,1,y,5);
6309 
6310   ierr = PetscMemcpy(&ls,&snes,sizeof(snes));CHKERRQ(ierr);
6311   ierr = PetscMemcpy(&lx,&u,sizeof(u));CHKERRQ(ierr);
6312   ierr = PetscMemcpy(&lxdot,&udot,sizeof(udot));CHKERRQ(ierr);
6313   ierr = PetscMemcpy(&ly,&y,sizeof(u));CHKERRQ(ierr);
6314 
6315   prhs[0] =  mxCreateDoubleScalar((double)ls);
6316   prhs[1] =  mxCreateDoubleScalar(time);
6317   prhs[2] =  mxCreateDoubleScalar((double)lx);
6318   prhs[3] =  mxCreateDoubleScalar((double)lxdot);
6319   prhs[4] =  mxCreateDoubleScalar((double)ly);
6320   prhs[5] =  mxCreateString(sctx->funcname);
6321   prhs[6] =  sctx->ctx;
6322   ierr    =  mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscTSComputeFunctionInternal");CHKERRQ(ierr);
6323   ierr    =  mxGetScalar(plhs[0]);CHKERRQ(ierr);
6324   mxDestroyArray(prhs[0]);
6325   mxDestroyArray(prhs[1]);
6326   mxDestroyArray(prhs[2]);
6327   mxDestroyArray(prhs[3]);
6328   mxDestroyArray(prhs[4]);
6329   mxDestroyArray(prhs[5]);
6330   mxDestroyArray(plhs[0]);
6331   PetscFunctionReturn(0);
6332 }
6333 
6334 /*
6335    TSSetFunctionMatlab - Sets the function evaluation routine and function
6336    vector for use by the TS routines in solving ODEs
6337    equations from MATLAB. Here the function is a string containing the name of a MATLAB function
6338 
6339    Logically Collective on TS
6340 
6341    Input Parameters:
6342 +  ts - the TS context
6343 -  func - function evaluation routine
6344 
6345    Calling sequence of func:
6346 $    func (TS ts,PetscReal time,Vec u,Vec udot,Vec f,void *ctx);
6347 
6348    Level: beginner
6349 
6350 .keywords: TS, nonlinear, set, function
6351 
6352 .seealso: TSGetFunction(), TSComputeFunction(), TSSetJacobian(), TSSetFunction()
6353 */
6354 PetscErrorCode  TSSetFunctionMatlab(TS ts,const char *func,mxArray *ctx)
6355 {
6356   PetscErrorCode  ierr;
6357   TSMatlabContext *sctx;
6358 
6359   PetscFunctionBegin;
6360   /* currently sctx is memory bleed */
6361   ierr = PetscNew(&sctx);CHKERRQ(ierr);
6362   ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr);
6363   /*
6364      This should work, but it doesn't
6365   sctx->ctx = ctx;
6366   mexMakeArrayPersistent(sctx->ctx);
6367   */
6368   sctx->ctx = mxDuplicateArray(ctx);
6369 
6370   ierr = TSSetIFunction(ts,NULL,TSComputeFunction_Matlab,sctx);CHKERRQ(ierr);
6371   PetscFunctionReturn(0);
6372 }
6373 
6374 /*
6375    TSComputeJacobian_Matlab - Calls the function that has been set with
6376                          TSSetJacobianMatlab().
6377 
6378    Collective on TS
6379 
6380    Input Parameters:
6381 +  ts - the TS context
6382 .  u - input vector
6383 .  A, B - the matrices
6384 -  ctx - user context
6385 
6386    Level: developer
6387 
6388 .keywords: TS, nonlinear, compute, function
6389 
6390 .seealso: TSSetFunction(), TSGetFunction()
6391 @*/
6392 PetscErrorCode  TSComputeJacobian_Matlab(TS ts,PetscReal time,Vec u,Vec udot,PetscReal shift,Mat A,Mat B,void *ctx)
6393 {
6394   PetscErrorCode  ierr;
6395   TSMatlabContext *sctx = (TSMatlabContext*)ctx;
6396   int             nlhs  = 2,nrhs = 9;
6397   mxArray         *plhs[2],*prhs[9];
6398   long long int   lx = 0,lxdot = 0,lA = 0,ls = 0, lB = 0;
6399 
6400   PetscFunctionBegin;
6401   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
6402   PetscValidHeaderSpecific(u,VEC_CLASSID,3);
6403 
6404   /* call Matlab function in ctx with arguments u and y */
6405 
6406   ierr = PetscMemcpy(&ls,&ts,sizeof(ts));CHKERRQ(ierr);
6407   ierr = PetscMemcpy(&lx,&u,sizeof(u));CHKERRQ(ierr);
6408   ierr = PetscMemcpy(&lxdot,&udot,sizeof(u));CHKERRQ(ierr);
6409   ierr = PetscMemcpy(&lA,A,sizeof(u));CHKERRQ(ierr);
6410   ierr = PetscMemcpy(&lB,B,sizeof(u));CHKERRQ(ierr);
6411 
6412   prhs[0] =  mxCreateDoubleScalar((double)ls);
6413   prhs[1] =  mxCreateDoubleScalar((double)time);
6414   prhs[2] =  mxCreateDoubleScalar((double)lx);
6415   prhs[3] =  mxCreateDoubleScalar((double)lxdot);
6416   prhs[4] =  mxCreateDoubleScalar((double)shift);
6417   prhs[5] =  mxCreateDoubleScalar((double)lA);
6418   prhs[6] =  mxCreateDoubleScalar((double)lB);
6419   prhs[7] =  mxCreateString(sctx->funcname);
6420   prhs[8] =  sctx->ctx;
6421   ierr    =  mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscTSComputeJacobianInternal");CHKERRQ(ierr);
6422   ierr    =  mxGetScalar(plhs[0]);CHKERRQ(ierr);
6423   mxDestroyArray(prhs[0]);
6424   mxDestroyArray(prhs[1]);
6425   mxDestroyArray(prhs[2]);
6426   mxDestroyArray(prhs[3]);
6427   mxDestroyArray(prhs[4]);
6428   mxDestroyArray(prhs[5]);
6429   mxDestroyArray(prhs[6]);
6430   mxDestroyArray(prhs[7]);
6431   mxDestroyArray(plhs[0]);
6432   mxDestroyArray(plhs[1]);
6433   PetscFunctionReturn(0);
6434 }
6435 
6436 /*
6437    TSSetJacobianMatlab - Sets the Jacobian function evaluation routine and two empty Jacobian matrices
6438    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
6439 
6440    Logically Collective on TS
6441 
6442    Input Parameters:
6443 +  ts - the TS context
6444 .  A,B - Jacobian matrices
6445 .  func - function evaluation routine
6446 -  ctx - user context
6447 
6448    Calling sequence of func:
6449 $    flag = func (TS ts,PetscReal time,Vec u,Vec udot,Mat A,Mat B,void *ctx);
6450 
6451    Level: developer
6452 
6453 .keywords: TS, nonlinear, set, function
6454 
6455 .seealso: TSGetFunction(), TSComputeFunction(), TSSetJacobian(), TSSetFunction()
6456 */
6457 PetscErrorCode  TSSetJacobianMatlab(TS ts,Mat A,Mat B,const char *func,mxArray *ctx)
6458 {
6459   PetscErrorCode  ierr;
6460   TSMatlabContext *sctx;
6461 
6462   PetscFunctionBegin;
6463   /* currently sctx is memory bleed */
6464   ierr = PetscNew(&sctx);CHKERRQ(ierr);
6465   ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr);
6466   /*
6467      This should work, but it doesn't
6468   sctx->ctx = ctx;
6469   mexMakeArrayPersistent(sctx->ctx);
6470   */
6471   sctx->ctx = mxDuplicateArray(ctx);
6472 
6473   ierr = TSSetIJacobian(ts,A,B,TSComputeJacobian_Matlab,sctx);CHKERRQ(ierr);
6474   PetscFunctionReturn(0);
6475 }
6476 
6477 /*
6478    TSMonitor_Matlab - Calls the function that has been set with TSMonitorSetMatlab().
6479 
6480    Collective on TS
6481 
6482 .seealso: TSSetFunction(), TSGetFunction()
6483 @*/
6484 PetscErrorCode  TSMonitor_Matlab(TS ts,PetscInt it, PetscReal time,Vec u, void *ctx)
6485 {
6486   PetscErrorCode  ierr;
6487   TSMatlabContext *sctx = (TSMatlabContext*)ctx;
6488   int             nlhs  = 1,nrhs = 6;
6489   mxArray         *plhs[1],*prhs[6];
6490   long long int   lx = 0,ls = 0;
6491 
6492   PetscFunctionBegin;
6493   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
6494   PetscValidHeaderSpecific(u,VEC_CLASSID,4);
6495 
6496   ierr = PetscMemcpy(&ls,&ts,sizeof(ts));CHKERRQ(ierr);
6497   ierr = PetscMemcpy(&lx,&u,sizeof(u));CHKERRQ(ierr);
6498 
6499   prhs[0] =  mxCreateDoubleScalar((double)ls);
6500   prhs[1] =  mxCreateDoubleScalar((double)it);
6501   prhs[2] =  mxCreateDoubleScalar((double)time);
6502   prhs[3] =  mxCreateDoubleScalar((double)lx);
6503   prhs[4] =  mxCreateString(sctx->funcname);
6504   prhs[5] =  sctx->ctx;
6505   ierr    =  mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscTSMonitorInternal");CHKERRQ(ierr);
6506   ierr    =  mxGetScalar(plhs[0]);CHKERRQ(ierr);
6507   mxDestroyArray(prhs[0]);
6508   mxDestroyArray(prhs[1]);
6509   mxDestroyArray(prhs[2]);
6510   mxDestroyArray(prhs[3]);
6511   mxDestroyArray(prhs[4]);
6512   mxDestroyArray(plhs[0]);
6513   PetscFunctionReturn(0);
6514 }
6515 
6516 /*
6517    TSMonitorSetMatlab - Sets the monitor function from Matlab
6518 
6519    Level: developer
6520 
6521 .keywords: TS, nonlinear, set, function
6522 
6523 .seealso: TSGetFunction(), TSComputeFunction(), TSSetJacobian(), TSSetFunction()
6524 */
6525 PetscErrorCode  TSMonitorSetMatlab(TS ts,const char *func,mxArray *ctx)
6526 {
6527   PetscErrorCode  ierr;
6528   TSMatlabContext *sctx;
6529 
6530   PetscFunctionBegin;
6531   /* currently sctx is memory bleed */
6532   ierr = PetscNew(&sctx);CHKERRQ(ierr);
6533   ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr);
6534   /*
6535      This should work, but it doesn't
6536   sctx->ctx = ctx;
6537   mexMakeArrayPersistent(sctx->ctx);
6538   */
6539   sctx->ctx = mxDuplicateArray(ctx);
6540 
6541   ierr = TSMonitorSet(ts,TSMonitor_Matlab,sctx,NULL);CHKERRQ(ierr);
6542   PetscFunctionReturn(0);
6543 }
6544 #endif
6545 
6546 /*@C
6547    TSMonitorLGSolution - Monitors progress of the TS solvers by plotting each component of the solution vector
6548        in a time based line graph
6549 
6550    Collective on TS
6551 
6552    Input Parameters:
6553 +  ts - the TS context
6554 .  step - current time-step
6555 .  ptime - current time
6556 .  u - current solution
6557 -  dctx - the TSMonitorLGCtx object that contains all the options for the monitoring, this is created with TSMonitorLGCtxCreate()
6558 
6559    Options Database:
6560 .   -ts_monitor_lg_solution_variables
6561 
6562    Level: intermediate
6563 
6564    Notes:
6565     Each process in a parallel run displays its component solutions in a separate window
6566 
6567 .keywords: TS,  vector, monitor, view
6568 
6569 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGCtxCreate(), TSMonitorLGCtxSetVariableNames(), TSMonitorLGCtxGetVariableNames(),
6570            TSMonitorLGSetVariableNames(), TSMonitorLGGetVariableNames(), TSMonitorLGSetDisplayVariables(), TSMonitorLGCtxSetDisplayVariables(),
6571            TSMonitorLGCtxSetTransform(), TSMonitorLGSetTransform(), TSMonitorLGError(), TSMonitorLGSNESIterations(), TSMonitorLGKSPIterations(),
6572            TSMonitorEnvelopeCtxCreate(), TSMonitorEnvelopeGetBounds(), TSMonitorEnvelopeCtxDestroy(), TSMonitorEnvelop()
6573 @*/
6574 PetscErrorCode  TSMonitorLGSolution(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dctx)
6575 {
6576   PetscErrorCode    ierr;
6577   TSMonitorLGCtx    ctx = (TSMonitorLGCtx)dctx;
6578   const PetscScalar *yy;
6579   Vec               v;
6580 
6581   PetscFunctionBegin;
6582   if (step < 0) PetscFunctionReturn(0); /* -1 indicates interpolated solution */
6583   if (!step) {
6584     PetscDrawAxis axis;
6585     PetscInt      dim;
6586     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
6587     ierr = PetscDrawAxisSetLabels(axis,"Solution as function of time","Time","Solution");CHKERRQ(ierr);
6588     if (!ctx->names) {
6589       PetscBool flg;
6590       /* user provides names of variables to plot but no names has been set so assume names are integer values */
6591       ierr = PetscOptionsHasName(((PetscObject)ts)->options,((PetscObject)ts)->prefix,"-ts_monitor_lg_solution_variables",&flg);CHKERRQ(ierr);
6592       if (flg) {
6593         PetscInt i,n;
6594         char     **names;
6595         ierr = VecGetSize(u,&n);CHKERRQ(ierr);
6596         ierr = PetscMalloc1(n+1,&names);CHKERRQ(ierr);
6597         for (i=0; i<n; i++) {
6598           ierr = PetscMalloc1(5,&names[i]);CHKERRQ(ierr);
6599           ierr = PetscSNPrintf(names[i],5,"%D",i);CHKERRQ(ierr);
6600         }
6601         names[n] = NULL;
6602         ctx->names = names;
6603       }
6604     }
6605     if (ctx->names && !ctx->displaynames) {
6606       char      **displaynames;
6607       PetscBool flg;
6608       ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
6609       ierr = PetscMalloc1(dim+1,&displaynames);CHKERRQ(ierr);
6610       ierr = PetscMemzero(displaynames,(dim+1)*sizeof(char*));CHKERRQ(ierr);
6611       ierr = PetscOptionsGetStringArray(((PetscObject)ts)->options,((PetscObject)ts)->prefix,"-ts_monitor_lg_solution_variables",displaynames,&dim,&flg);CHKERRQ(ierr);
6612       if (flg) {
6613         ierr = TSMonitorLGCtxSetDisplayVariables(ctx,(const char *const *)displaynames);CHKERRQ(ierr);
6614       }
6615       ierr = PetscStrArrayDestroy(&displaynames);CHKERRQ(ierr);
6616     }
6617     if (ctx->displaynames) {
6618       ierr = PetscDrawLGSetDimension(ctx->lg,ctx->ndisplayvariables);CHKERRQ(ierr);
6619       ierr = PetscDrawLGSetLegend(ctx->lg,(const char *const *)ctx->displaynames);CHKERRQ(ierr);
6620     } else if (ctx->names) {
6621       ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
6622       ierr = PetscDrawLGSetDimension(ctx->lg,dim);CHKERRQ(ierr);
6623       ierr = PetscDrawLGSetLegend(ctx->lg,(const char *const *)ctx->names);CHKERRQ(ierr);
6624     } else {
6625       ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
6626       ierr = PetscDrawLGSetDimension(ctx->lg,dim);CHKERRQ(ierr);
6627     }
6628     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
6629   }
6630 
6631   if (!ctx->transform) v = u;
6632   else {ierr = (*ctx->transform)(ctx->transformctx,u,&v);CHKERRQ(ierr);}
6633   ierr = VecGetArrayRead(v,&yy);CHKERRQ(ierr);
6634   if (ctx->displaynames) {
6635     PetscInt i;
6636     for (i=0; i<ctx->ndisplayvariables; i++)
6637       ctx->displayvalues[i] = PetscRealPart(yy[ctx->displayvariables[i]]);
6638     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,ctx->displayvalues);CHKERRQ(ierr);
6639   } else {
6640 #if defined(PETSC_USE_COMPLEX)
6641     PetscInt  i,n;
6642     PetscReal *yreal;
6643     ierr = VecGetLocalSize(v,&n);CHKERRQ(ierr);
6644     ierr = PetscMalloc1(n,&yreal);CHKERRQ(ierr);
6645     for (i=0; i<n; i++) yreal[i] = PetscRealPart(yy[i]);
6646     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yreal);CHKERRQ(ierr);
6647     ierr = PetscFree(yreal);CHKERRQ(ierr);
6648 #else
6649     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yy);CHKERRQ(ierr);
6650 #endif
6651   }
6652   ierr = VecRestoreArrayRead(v,&yy);CHKERRQ(ierr);
6653   if (ctx->transform) {ierr = VecDestroy(&v);CHKERRQ(ierr);}
6654 
6655   if (((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason)) {
6656     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
6657     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
6658   }
6659   PetscFunctionReturn(0);
6660 }
6661 
6662 /*@C
6663    TSMonitorLGSetVariableNames - Sets the name of each component in the solution vector so that it may be displayed in the plot
6664 
6665    Collective on TS
6666 
6667    Input Parameters:
6668 +  ts - the TS context
6669 -  names - the names of the components, final string must be NULL
6670 
6671    Level: intermediate
6672 
6673    Notes:
6674     If the TS object does not have a TSMonitorLGCtx associated with it then this function is ignored
6675 
6676 .keywords: TS,  vector, monitor, view
6677 
6678 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetDisplayVariables(), TSMonitorLGCtxSetVariableNames()
6679 @*/
6680 PetscErrorCode  TSMonitorLGSetVariableNames(TS ts,const char * const *names)
6681 {
6682   PetscErrorCode    ierr;
6683   PetscInt          i;
6684 
6685   PetscFunctionBegin;
6686   for (i=0; i<ts->numbermonitors; i++) {
6687     if (ts->monitor[i] == TSMonitorLGSolution) {
6688       ierr = TSMonitorLGCtxSetVariableNames((TSMonitorLGCtx)ts->monitorcontext[i],names);CHKERRQ(ierr);
6689       break;
6690     }
6691   }
6692   PetscFunctionReturn(0);
6693 }
6694 
6695 /*@C
6696    TSMonitorLGCtxSetVariableNames - Sets 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 Parameters:
6701 +  ts - the TS context
6702 -  names - the names of the components, final string must be NULL
6703 
6704    Level: intermediate
6705 
6706 .keywords: TS,  vector, monitor, view
6707 
6708 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetDisplayVariables(), TSMonitorLGSetVariableNames()
6709 @*/
6710 PetscErrorCode  TSMonitorLGCtxSetVariableNames(TSMonitorLGCtx ctx,const char * const *names)
6711 {
6712   PetscErrorCode    ierr;
6713 
6714   PetscFunctionBegin;
6715   ierr = PetscStrArrayDestroy(&ctx->names);CHKERRQ(ierr);
6716   ierr = PetscStrArrayallocpy(names,&ctx->names);CHKERRQ(ierr);
6717   PetscFunctionReturn(0);
6718 }
6719 
6720 /*@C
6721    TSMonitorLGGetVariableNames - Gets the name of each component in the solution vector so that it may be displayed in the plot
6722 
6723    Collective on TS
6724 
6725    Input Parameter:
6726 .  ts - the TS context
6727 
6728    Output Parameter:
6729 .  names - the names of the components, final string must be NULL
6730 
6731    Level: intermediate
6732 
6733    Notes:
6734     If the TS object does not have a TSMonitorLGCtx associated with it then this function is ignored
6735 
6736 .keywords: TS,  vector, monitor, view
6737 
6738 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetDisplayVariables()
6739 @*/
6740 PetscErrorCode  TSMonitorLGGetVariableNames(TS ts,const char *const **names)
6741 {
6742   PetscInt       i;
6743 
6744   PetscFunctionBegin;
6745   *names = NULL;
6746   for (i=0; i<ts->numbermonitors; i++) {
6747     if (ts->monitor[i] == TSMonitorLGSolution) {
6748       TSMonitorLGCtx  ctx = (TSMonitorLGCtx) ts->monitorcontext[i];
6749       *names = (const char *const *)ctx->names;
6750       break;
6751     }
6752   }
6753   PetscFunctionReturn(0);
6754 }
6755 
6756 /*@C
6757    TSMonitorLGCtxSetDisplayVariables - Sets the variables that are to be display in the monitor
6758 
6759    Collective on TS
6760 
6761    Input Parameters:
6762 +  ctx - the TSMonitorLG context
6763 .  displaynames - the names of the components, final string must be NULL
6764 
6765    Level: intermediate
6766 
6767 .keywords: TS,  vector, monitor, view
6768 
6769 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetVariableNames()
6770 @*/
6771 PetscErrorCode  TSMonitorLGCtxSetDisplayVariables(TSMonitorLGCtx ctx,const char * const *displaynames)
6772 {
6773   PetscInt          j = 0,k;
6774   PetscErrorCode    ierr;
6775 
6776   PetscFunctionBegin;
6777   if (!ctx->names) PetscFunctionReturn(0);
6778   ierr = PetscStrArrayDestroy(&ctx->displaynames);CHKERRQ(ierr);
6779   ierr = PetscStrArrayallocpy(displaynames,&ctx->displaynames);CHKERRQ(ierr);
6780   while (displaynames[j]) j++;
6781   ctx->ndisplayvariables = j;
6782   ierr = PetscMalloc1(ctx->ndisplayvariables,&ctx->displayvariables);CHKERRQ(ierr);
6783   ierr = PetscMalloc1(ctx->ndisplayvariables,&ctx->displayvalues);CHKERRQ(ierr);
6784   j = 0;
6785   while (displaynames[j]) {
6786     k = 0;
6787     while (ctx->names[k]) {
6788       PetscBool flg;
6789       ierr = PetscStrcmp(displaynames[j],ctx->names[k],&flg);CHKERRQ(ierr);
6790       if (flg) {
6791         ctx->displayvariables[j] = k;
6792         break;
6793       }
6794       k++;
6795     }
6796     j++;
6797   }
6798   PetscFunctionReturn(0);
6799 }
6800 
6801 /*@C
6802    TSMonitorLGSetDisplayVariables - Sets the variables that are to be display in the monitor
6803 
6804    Collective on TS
6805 
6806    Input Parameters:
6807 +  ts - the TS context
6808 .  displaynames - the names of the components, final string must be NULL
6809 
6810    Notes:
6811     If the TS object does not have a TSMonitorLGCtx associated with it then this function is ignored
6812 
6813    Level: intermediate
6814 
6815 .keywords: TS,  vector, monitor, view
6816 
6817 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetVariableNames()
6818 @*/
6819 PetscErrorCode  TSMonitorLGSetDisplayVariables(TS ts,const char * const *displaynames)
6820 {
6821   PetscInt          i;
6822   PetscErrorCode    ierr;
6823 
6824   PetscFunctionBegin;
6825   for (i=0; i<ts->numbermonitors; i++) {
6826     if (ts->monitor[i] == TSMonitorLGSolution) {
6827       ierr = TSMonitorLGCtxSetDisplayVariables((TSMonitorLGCtx)ts->monitorcontext[i],displaynames);CHKERRQ(ierr);
6828       break;
6829     }
6830   }
6831   PetscFunctionReturn(0);
6832 }
6833 
6834 /*@C
6835    TSMonitorLGSetTransform - Solution vector will be transformed by provided function before being displayed
6836 
6837    Collective on TS
6838 
6839    Input Parameters:
6840 +  ts - the TS context
6841 .  transform - the transform function
6842 .  destroy - function to destroy the optional context
6843 -  ctx - optional context used by transform function
6844 
6845    Notes:
6846     If the TS object does not have a TSMonitorLGCtx associated with it then this function is ignored
6847 
6848    Level: intermediate
6849 
6850 .keywords: TS,  vector, monitor, view
6851 
6852 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetVariableNames(), TSMonitorLGCtxSetTransform()
6853 @*/
6854 PetscErrorCode  TSMonitorLGSetTransform(TS ts,PetscErrorCode (*transform)(void*,Vec,Vec*),PetscErrorCode (*destroy)(void*),void *tctx)
6855 {
6856   PetscInt          i;
6857   PetscErrorCode    ierr;
6858 
6859   PetscFunctionBegin;
6860   for (i=0; i<ts->numbermonitors; i++) {
6861     if (ts->monitor[i] == TSMonitorLGSolution) {
6862       ierr = TSMonitorLGCtxSetTransform((TSMonitorLGCtx)ts->monitorcontext[i],transform,destroy,tctx);CHKERRQ(ierr);
6863     }
6864   }
6865   PetscFunctionReturn(0);
6866 }
6867 
6868 /*@C
6869    TSMonitorLGCtxSetTransform - Solution vector will be transformed by provided function before being displayed
6870 
6871    Collective on TSLGCtx
6872 
6873    Input Parameters:
6874 +  ts - the TS context
6875 .  transform - the transform function
6876 .  destroy - function to destroy the optional context
6877 -  ctx - optional context used by transform function
6878 
6879    Level: intermediate
6880 
6881 .keywords: TS,  vector, monitor, view
6882 
6883 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetVariableNames(), TSMonitorLGSetTransform()
6884 @*/
6885 PetscErrorCode  TSMonitorLGCtxSetTransform(TSMonitorLGCtx ctx,PetscErrorCode (*transform)(void*,Vec,Vec*),PetscErrorCode (*destroy)(void*),void *tctx)
6886 {
6887   PetscFunctionBegin;
6888   ctx->transform    = transform;
6889   ctx->transformdestroy = destroy;
6890   ctx->transformctx = tctx;
6891   PetscFunctionReturn(0);
6892 }
6893 
6894 /*@C
6895    TSMonitorLGError - Monitors progress of the TS solvers by plotting each component of the error
6896        in a time based line graph
6897 
6898    Collective on TS
6899 
6900    Input Parameters:
6901 +  ts - the TS context
6902 .  step - current time-step
6903 .  ptime - current time
6904 .  u - current solution
6905 -  dctx - TSMonitorLGCtx object created with TSMonitorLGCtxCreate()
6906 
6907    Level: intermediate
6908 
6909    Notes:
6910     Each process in a parallel run displays its component errors in a separate window
6911 
6912    The user must provide the solution using TSSetSolutionFunction() to use this monitor.
6913 
6914    Options Database Keys:
6915 .  -ts_monitor_lg_error - create a graphical monitor of error history
6916 
6917 .keywords: TS,  vector, monitor, view
6918 
6919 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSSetSolutionFunction()
6920 @*/
6921 PetscErrorCode  TSMonitorLGError(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
6922 {
6923   PetscErrorCode    ierr;
6924   TSMonitorLGCtx    ctx = (TSMonitorLGCtx)dummy;
6925   const PetscScalar *yy;
6926   Vec               y;
6927 
6928   PetscFunctionBegin;
6929   if (!step) {
6930     PetscDrawAxis axis;
6931     PetscInt      dim;
6932     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
6933     ierr = PetscDrawAxisSetLabels(axis,"Error in solution as function of time","Time","Error");CHKERRQ(ierr);
6934     ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
6935     ierr = PetscDrawLGSetDimension(ctx->lg,dim);CHKERRQ(ierr);
6936     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
6937   }
6938   ierr = VecDuplicate(u,&y);CHKERRQ(ierr);
6939   ierr = TSComputeSolutionFunction(ts,ptime,y);CHKERRQ(ierr);
6940   ierr = VecAXPY(y,-1.0,u);CHKERRQ(ierr);
6941   ierr = VecGetArrayRead(y,&yy);CHKERRQ(ierr);
6942 #if defined(PETSC_USE_COMPLEX)
6943   {
6944     PetscReal *yreal;
6945     PetscInt  i,n;
6946     ierr = VecGetLocalSize(y,&n);CHKERRQ(ierr);
6947     ierr = PetscMalloc1(n,&yreal);CHKERRQ(ierr);
6948     for (i=0; i<n; i++) yreal[i] = PetscRealPart(yy[i]);
6949     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yreal);CHKERRQ(ierr);
6950     ierr = PetscFree(yreal);CHKERRQ(ierr);
6951   }
6952 #else
6953   ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yy);CHKERRQ(ierr);
6954 #endif
6955   ierr = VecRestoreArrayRead(y,&yy);CHKERRQ(ierr);
6956   ierr = VecDestroy(&y);CHKERRQ(ierr);
6957   if (((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason)) {
6958     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
6959     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
6960   }
6961   PetscFunctionReturn(0);
6962 }
6963 
6964 /*@C
6965    TSMonitorSPSwarmSolution - Graphically displays phase plots of DMSwarm particles on a scatter plot
6966 
6967    Input Parameters:
6968 +  ts - the TS context
6969 .  step - current time-step
6970 .  ptime - current time
6971 .  u - current solution
6972 -  dctx - the TSMonitorSPCtx object that contains all the options for the monitoring, this is created with TSMonitorSPCtxCreate()
6973 
6974    Options Database:
6975 .   -ts_monitor_sp_swarm
6976 
6977    Level: intermediate
6978 
6979 .keywords: TS,  vector, monitor, view, swarm
6980 @*/
6981 PetscErrorCode TSMonitorSPSwarmSolution(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dctx)
6982 {
6983   PetscErrorCode    ierr;
6984   TSMonitorSPCtx    ctx = (TSMonitorSPCtx)dctx;
6985   const PetscScalar *yy;
6986   PetscReal       *y,*x;
6987   PetscInt          Np, p, dim=2;
6988   DM                dm;
6989 
6990   PetscFunctionBegin;
6991 
6992   if (step < 0) PetscFunctionReturn(0); /* -1 indicates interpolated solution */
6993   if (!step) {
6994     PetscDrawAxis axis;
6995     ierr = PetscDrawSPGetAxis(ctx->sp,&axis);CHKERRQ(ierr);
6996     ierr = PetscDrawAxisSetLabels(axis,"Particles","X","Y");CHKERRQ(ierr);
6997     ierr = PetscDrawAxisSetLimits(axis, -5, 5, -5, 5);CHKERRQ(ierr);
6998     ierr = PetscDrawAxisSetHoldLimits(axis, PETSC_TRUE);CHKERRQ(ierr);
6999     ierr = TSGetDM(ts, &dm);CHKERRQ(ierr);
7000     ierr = DMGetDimension(dm, &dim);
7001     if(dim!=2) SETERRQ(PETSC_COMM_SELF, ierr, "Dimensions improper for monitor arguments! Current support: two dimensions.");CHKERRQ(ierr);
7002     ierr = VecGetLocalSize(u, &Np);CHKERRQ(ierr);
7003     Np /= 2*dim;
7004     ierr = PetscDrawSPSetDimension(ctx->sp, Np);CHKERRQ(ierr);
7005     ierr = PetscDrawSPReset(ctx->sp);CHKERRQ(ierr);
7006   }
7007 
7008   ierr = VecGetLocalSize(u, &Np);CHKERRQ(ierr);
7009   Np /= 2*dim;
7010   ierr = VecGetArrayRead(u,&yy);CHKERRQ(ierr);
7011   ierr = PetscMalloc2(Np, &x, Np, &y);CHKERRQ(ierr);
7012   /* get points from solution vector */
7013   for (p=0; p<Np; ++p){
7014     x[p] = PetscRealPart(yy[2*dim*p]);
7015     y[p] = PetscRealPart(yy[2*dim*p+1]);
7016   }
7017   ierr = VecRestoreArrayRead(u,&yy);CHKERRQ(ierr);
7018 
7019   if (((ctx->howoften > 0) && (!(step % ctx->howoften))) || ((ctx->howoften == -1) && ts->reason)) {
7020     ierr = PetscDrawSPAddPoint(ctx->sp,x,y);CHKERRQ(ierr);
7021     ierr = PetscDrawSPDraw(ctx->sp,PETSC_FALSE);CHKERRQ(ierr);
7022     ierr = PetscDrawSPSave(ctx->sp);CHKERRQ(ierr);
7023   }
7024 
7025   ierr = PetscFree2(x, y);CHKERRQ(ierr);
7026 
7027   PetscFunctionReturn(0);
7028 }
7029 
7030 
7031 
7032 /*@C
7033    TSMonitorError - Monitors progress of the TS solvers by printing the 2 norm of the error at each timestep
7034 
7035    Collective on TS
7036 
7037    Input Parameters:
7038 +  ts - the TS context
7039 .  step - current time-step
7040 .  ptime - current time
7041 .  u - current solution
7042 -  dctx - unused context
7043 
7044    Level: intermediate
7045 
7046    The user must provide the solution using TSSetSolutionFunction() to use this monitor.
7047 
7048    Options Database Keys:
7049 .  -ts_monitor_error - create a graphical monitor of error history
7050 
7051 .keywords: TS,  vector, monitor, view
7052 
7053 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSSetSolutionFunction()
7054 @*/
7055 PetscErrorCode  TSMonitorError(TS ts,PetscInt step,PetscReal ptime,Vec u,PetscViewerAndFormat *vf)
7056 {
7057   PetscErrorCode    ierr;
7058   Vec               y;
7059   PetscReal         nrm;
7060   PetscBool         flg;
7061 
7062   PetscFunctionBegin;
7063   ierr = VecDuplicate(u,&y);CHKERRQ(ierr);
7064   ierr = TSComputeSolutionFunction(ts,ptime,y);CHKERRQ(ierr);
7065   ierr = VecAXPY(y,-1.0,u);CHKERRQ(ierr);
7066   ierr = PetscObjectTypeCompare((PetscObject)vf->viewer,PETSCVIEWERASCII,&flg);CHKERRQ(ierr);
7067   if (flg) {
7068     ierr = VecNorm(y,NORM_2,&nrm);CHKERRQ(ierr);
7069     ierr = PetscViewerASCIIPrintf(vf->viewer,"2-norm of error %g\n",(double)nrm);CHKERRQ(ierr);
7070   }
7071   ierr = PetscObjectTypeCompare((PetscObject)vf->viewer,PETSCVIEWERDRAW,&flg);CHKERRQ(ierr);
7072   if (flg) {
7073     ierr = VecView(y,vf->viewer);CHKERRQ(ierr);
7074   }
7075   ierr = VecDestroy(&y);CHKERRQ(ierr);
7076   PetscFunctionReturn(0);
7077 }
7078 
7079 PetscErrorCode TSMonitorLGSNESIterations(TS ts,PetscInt n,PetscReal ptime,Vec v,void *monctx)
7080 {
7081   TSMonitorLGCtx ctx = (TSMonitorLGCtx) monctx;
7082   PetscReal      x   = ptime,y;
7083   PetscErrorCode ierr;
7084   PetscInt       its;
7085 
7086   PetscFunctionBegin;
7087   if (n < 0) PetscFunctionReturn(0); /* -1 indicates interpolated solution */
7088   if (!n) {
7089     PetscDrawAxis axis;
7090     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
7091     ierr = PetscDrawAxisSetLabels(axis,"Nonlinear iterations as function of time","Time","SNES Iterations");CHKERRQ(ierr);
7092     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
7093     ctx->snes_its = 0;
7094   }
7095   ierr = TSGetSNESIterations(ts,&its);CHKERRQ(ierr);
7096   y    = its - ctx->snes_its;
7097   ierr = PetscDrawLGAddPoint(ctx->lg,&x,&y);CHKERRQ(ierr);
7098   if (((ctx->howoften > 0) && (!(n % ctx->howoften)) && (n > -1)) || ((ctx->howoften == -1) && (n == -1))) {
7099     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
7100     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
7101   }
7102   ctx->snes_its = its;
7103   PetscFunctionReturn(0);
7104 }
7105 
7106 PetscErrorCode TSMonitorLGKSPIterations(TS ts,PetscInt n,PetscReal ptime,Vec v,void *monctx)
7107 {
7108   TSMonitorLGCtx ctx = (TSMonitorLGCtx) monctx;
7109   PetscReal      x   = ptime,y;
7110   PetscErrorCode ierr;
7111   PetscInt       its;
7112 
7113   PetscFunctionBegin;
7114   if (n < 0) PetscFunctionReturn(0); /* -1 indicates interpolated solution */
7115   if (!n) {
7116     PetscDrawAxis axis;
7117     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
7118     ierr = PetscDrawAxisSetLabels(axis,"Linear iterations as function of time","Time","KSP Iterations");CHKERRQ(ierr);
7119     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
7120     ctx->ksp_its = 0;
7121   }
7122   ierr = TSGetKSPIterations(ts,&its);CHKERRQ(ierr);
7123   y    = its - ctx->ksp_its;
7124   ierr = PetscDrawLGAddPoint(ctx->lg,&x,&y);CHKERRQ(ierr);
7125   if (((ctx->howoften > 0) && (!(n % ctx->howoften)) && (n > -1)) || ((ctx->howoften == -1) && (n == -1))) {
7126     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
7127     ierr = PetscDrawLGSave(ctx->lg);CHKERRQ(ierr);
7128   }
7129   ctx->ksp_its = its;
7130   PetscFunctionReturn(0);
7131 }
7132 
7133 /*@
7134    TSComputeLinearStability - computes the linear stability function at a point
7135 
7136    Collective on TS and Vec
7137 
7138    Input Parameters:
7139 +  ts - the TS context
7140 -  xr,xi - real and imaginary part of input arguments
7141 
7142    Output Parameters:
7143 .  yr,yi - real and imaginary part of function value
7144 
7145    Level: developer
7146 
7147 .keywords: TS, compute
7148 
7149 .seealso: TSSetRHSFunction(), TSComputeIFunction()
7150 @*/
7151 PetscErrorCode TSComputeLinearStability(TS ts,PetscReal xr,PetscReal xi,PetscReal *yr,PetscReal *yi)
7152 {
7153   PetscErrorCode ierr;
7154 
7155   PetscFunctionBegin;
7156   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
7157   if (!ts->ops->linearstability) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Linearized stability function not provided for this method");
7158   ierr = (*ts->ops->linearstability)(ts,xr,xi,yr,yi);CHKERRQ(ierr);
7159   PetscFunctionReturn(0);
7160 }
7161 
7162 /* ------------------------------------------------------------------------*/
7163 /*@C
7164    TSMonitorEnvelopeCtxCreate - Creates a context for use with TSMonitorEnvelope()
7165 
7166    Collective on TS
7167 
7168    Input Parameters:
7169 .  ts  - the ODE solver object
7170 
7171    Output Parameter:
7172 .  ctx - the context
7173 
7174    Level: intermediate
7175 
7176 .keywords: TS, monitor, line graph, residual, seealso
7177 
7178 .seealso: TSMonitorLGTimeStep(), TSMonitorSet(), TSMonitorLGSolution(), TSMonitorLGError()
7179 
7180 @*/
7181 PetscErrorCode  TSMonitorEnvelopeCtxCreate(TS ts,TSMonitorEnvelopeCtx *ctx)
7182 {
7183   PetscErrorCode ierr;
7184 
7185   PetscFunctionBegin;
7186   ierr = PetscNew(ctx);CHKERRQ(ierr);
7187   PetscFunctionReturn(0);
7188 }
7189 
7190 /*@C
7191    TSMonitorEnvelope - Monitors the maximum and minimum value of each component of the solution
7192 
7193    Collective on TS
7194 
7195    Input Parameters:
7196 +  ts - the TS context
7197 .  step - current time-step
7198 .  ptime - current time
7199 .  u  - current solution
7200 -  dctx - the envelope context
7201 
7202    Options Database:
7203 .  -ts_monitor_envelope
7204 
7205    Level: intermediate
7206 
7207    Notes:
7208     after a solve you can use TSMonitorEnvelopeGetBounds() to access the envelope
7209 
7210 .keywords: TS,  vector, monitor, view
7211 
7212 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorEnvelopeGetBounds(), TSMonitorEnvelopeCtxCreate()
7213 @*/
7214 PetscErrorCode  TSMonitorEnvelope(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dctx)
7215 {
7216   PetscErrorCode       ierr;
7217   TSMonitorEnvelopeCtx ctx = (TSMonitorEnvelopeCtx)dctx;
7218 
7219   PetscFunctionBegin;
7220   if (!ctx->max) {
7221     ierr = VecDuplicate(u,&ctx->max);CHKERRQ(ierr);
7222     ierr = VecDuplicate(u,&ctx->min);CHKERRQ(ierr);
7223     ierr = VecCopy(u,ctx->max);CHKERRQ(ierr);
7224     ierr = VecCopy(u,ctx->min);CHKERRQ(ierr);
7225   } else {
7226     ierr = VecPointwiseMax(ctx->max,u,ctx->max);CHKERRQ(ierr);
7227     ierr = VecPointwiseMin(ctx->min,u,ctx->min);CHKERRQ(ierr);
7228   }
7229   PetscFunctionReturn(0);
7230 }
7231 
7232 /*@C
7233    TSMonitorEnvelopeGetBounds - Gets the bounds for the components of the solution
7234 
7235    Collective on TS
7236 
7237    Input Parameter:
7238 .  ts - the TS context
7239 
7240    Output Parameter:
7241 +  max - the maximum values
7242 -  min - the minimum values
7243 
7244    Notes:
7245     If the TS does not have a TSMonitorEnvelopeCtx associated with it then this function is ignored
7246 
7247    Level: intermediate
7248 
7249 .keywords: TS,  vector, monitor, view
7250 
7251 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorLGSetDisplayVariables()
7252 @*/
7253 PetscErrorCode  TSMonitorEnvelopeGetBounds(TS ts,Vec *max,Vec *min)
7254 {
7255   PetscInt i;
7256 
7257   PetscFunctionBegin;
7258   if (max) *max = NULL;
7259   if (min) *min = NULL;
7260   for (i=0; i<ts->numbermonitors; i++) {
7261     if (ts->monitor[i] == TSMonitorEnvelope) {
7262       TSMonitorEnvelopeCtx  ctx = (TSMonitorEnvelopeCtx) ts->monitorcontext[i];
7263       if (max) *max = ctx->max;
7264       if (min) *min = ctx->min;
7265       break;
7266     }
7267   }
7268   PetscFunctionReturn(0);
7269 }
7270 
7271 /*@C
7272    TSMonitorEnvelopeCtxDestroy - Destroys a context that was created  with TSMonitorEnvelopeCtxCreate().
7273 
7274    Collective on TSMonitorEnvelopeCtx
7275 
7276    Input Parameter:
7277 .  ctx - the monitor context
7278 
7279    Level: intermediate
7280 
7281 .keywords: TS, monitor, line graph, destroy
7282 
7283 .seealso: TSMonitorLGCtxCreate(),  TSMonitorSet(), TSMonitorLGTimeStep()
7284 @*/
7285 PetscErrorCode  TSMonitorEnvelopeCtxDestroy(TSMonitorEnvelopeCtx *ctx)
7286 {
7287   PetscErrorCode ierr;
7288 
7289   PetscFunctionBegin;
7290   ierr = VecDestroy(&(*ctx)->min);CHKERRQ(ierr);
7291   ierr = VecDestroy(&(*ctx)->max);CHKERRQ(ierr);
7292   ierr = PetscFree(*ctx);CHKERRQ(ierr);
7293   PetscFunctionReturn(0);
7294 }
7295 
7296 /*@
7297    TSRestartStep - Flags the solver to restart the next step
7298 
7299    Collective on TS
7300 
7301    Input Parameter:
7302 .  ts - the TS context obtained from TSCreate()
7303 
7304    Level: advanced
7305 
7306    Notes:
7307    Multistep methods like BDF or Runge-Kutta methods with FSAL property require restarting the solver in the event of
7308    discontinuities. These discontinuities may be introduced as a consequence of explicitly modifications to the solution
7309    vector (which PETSc attempts to detect and handle) or problem coefficients (which PETSc is not able to detect). For
7310    the sake of correctness and maximum safety, users are expected to call TSRestart() whenever they introduce
7311    discontinuities in callback routines (e.g. prestep and poststep routines, or implicit/rhs function routines with
7312    discontinuous source terms).
7313 
7314 .keywords: TS, timestep, restart
7315 
7316 .seealso: TSSolve(), TSSetPreStep(), TSSetPostStep()
7317 @*/
7318 PetscErrorCode TSRestartStep(TS ts)
7319 {
7320   PetscFunctionBegin;
7321   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
7322   ts->steprestart = PETSC_TRUE;
7323   PetscFunctionReturn(0);
7324 }
7325 
7326 /*@
7327    TSRollBack - Rolls back one time step
7328 
7329    Collective on TS
7330 
7331    Input Parameter:
7332 .  ts - the TS context obtained from TSCreate()
7333 
7334    Level: advanced
7335 
7336 .keywords: TS, timestep, rollback
7337 
7338 .seealso: TSCreate(), TSSetUp(), TSDestroy(), TSSolve(), TSSetPreStep(), TSSetPreStage(), TSInterpolate()
7339 @*/
7340 PetscErrorCode  TSRollBack(TS ts)
7341 {
7342   PetscErrorCode ierr;
7343 
7344   PetscFunctionBegin;
7345   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
7346   if (ts->steprollback) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONGSTATE,"TSRollBack already called");
7347   if (!ts->ops->rollback) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSRollBack not implemented for type '%s'",((PetscObject)ts)->type_name);
7348   ierr = (*ts->ops->rollback)(ts);CHKERRQ(ierr);
7349   ts->time_step = ts->ptime - ts->ptime_prev;
7350   ts->ptime = ts->ptime_prev;
7351   ts->ptime_prev = ts->ptime_prev_rollback;
7352   ts->steps--;
7353   ts->steprollback = PETSC_TRUE;
7354   PetscFunctionReturn(0);
7355 }
7356 
7357 /*@
7358    TSGetStages - Get the number of stages and stage values
7359 
7360    Input Parameter:
7361 .  ts - the TS context obtained from TSCreate()
7362 
7363    Output Parameters:
7364 +  ns - the number of stages
7365 -  Y - the current stage vectors
7366 
7367    Level: advanced
7368 
7369    Notes: Both ns and Y can be NULL.
7370 
7371 .keywords: TS, getstages
7372 
7373 .seealso: TSCreate()
7374 @*/
7375 PetscErrorCode  TSGetStages(TS ts,PetscInt *ns,Vec **Y)
7376 {
7377   PetscErrorCode ierr;
7378 
7379   PetscFunctionBegin;
7380   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
7381   if (ns) PetscValidPointer(ns,2);
7382   if (Y) PetscValidPointer(Y,3);
7383   if (!ts->ops->getstages) {
7384     if (ns) *ns = 0;
7385     if (Y) *Y = NULL;
7386   } else {
7387     ierr = (*ts->ops->getstages)(ts,ns,Y);CHKERRQ(ierr);
7388   }
7389   PetscFunctionReturn(0);
7390 }
7391 
7392 /*@C
7393   TSComputeIJacobianDefaultColor - Computes the Jacobian using finite differences and coloring to exploit matrix sparsity.
7394 
7395   Collective on SNES
7396 
7397   Input Parameters:
7398 + ts - the TS context
7399 . t - current timestep
7400 . U - state vector
7401 . Udot - time derivative of state vector
7402 . shift - shift to apply, see note below
7403 - ctx - an optional user context
7404 
7405   Output Parameters:
7406 + J - Jacobian matrix (not altered in this routine)
7407 - B - newly computed Jacobian matrix to use with preconditioner (generally the same as J)
7408 
7409   Level: intermediate
7410 
7411   Notes:
7412   If F(t,U,Udot)=0 is the DAE, the required Jacobian is
7413 
7414   dF/dU + shift*dF/dUdot
7415 
7416   Most users should not need to explicitly call this routine, as it
7417   is used internally within the nonlinear solvers.
7418 
7419   This will first try to get the coloring from the DM.  If the DM type has no coloring
7420   routine, then it will try to get the coloring from the matrix.  This requires that the
7421   matrix have nonzero entries precomputed.
7422 
7423 .keywords: TS, finite differences, Jacobian, coloring, sparse
7424 .seealso: TSSetIJacobian(), MatFDColoringCreate(), MatFDColoringSetFunction()
7425 @*/
7426 PetscErrorCode TSComputeIJacobianDefaultColor(TS ts,PetscReal t,Vec U,Vec Udot,PetscReal shift,Mat J,Mat B,void *ctx)
7427 {
7428   SNES           snes;
7429   MatFDColoring  color;
7430   PetscBool      hascolor, matcolor = PETSC_FALSE;
7431   PetscErrorCode ierr;
7432 
7433   PetscFunctionBegin;
7434   ierr = PetscOptionsGetBool(((PetscObject)ts)->options,((PetscObject) ts)->prefix, "-ts_fd_color_use_mat", &matcolor, NULL);CHKERRQ(ierr);
7435   ierr = PetscObjectQuery((PetscObject) B, "TSMatFDColoring", (PetscObject *) &color);CHKERRQ(ierr);
7436   if (!color) {
7437     DM         dm;
7438     ISColoring iscoloring;
7439 
7440     ierr = TSGetDM(ts, &dm);CHKERRQ(ierr);
7441     ierr = DMHasColoring(dm, &hascolor);CHKERRQ(ierr);
7442     if (hascolor && !matcolor) {
7443       ierr = DMCreateColoring(dm, IS_COLORING_GLOBAL, &iscoloring);CHKERRQ(ierr);
7444       ierr = MatFDColoringCreate(B, iscoloring, &color);CHKERRQ(ierr);
7445       ierr = MatFDColoringSetFunction(color, (PetscErrorCode (*)(void)) SNESTSFormFunction, (void *) ts);CHKERRQ(ierr);
7446       ierr = MatFDColoringSetFromOptions(color);CHKERRQ(ierr);
7447       ierr = MatFDColoringSetUp(B, iscoloring, color);CHKERRQ(ierr);
7448       ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
7449     } else {
7450       MatColoring mc;
7451 
7452       ierr = MatColoringCreate(B, &mc);CHKERRQ(ierr);
7453       ierr = MatColoringSetDistance(mc, 2);CHKERRQ(ierr);
7454       ierr = MatColoringSetType(mc, MATCOLORINGSL);CHKERRQ(ierr);
7455       ierr = MatColoringSetFromOptions(mc);CHKERRQ(ierr);
7456       ierr = MatColoringApply(mc, &iscoloring);CHKERRQ(ierr);
7457       ierr = MatColoringDestroy(&mc);CHKERRQ(ierr);
7458       ierr = MatFDColoringCreate(B, iscoloring, &color);CHKERRQ(ierr);
7459       ierr = MatFDColoringSetFunction(color, (PetscErrorCode (*)(void)) SNESTSFormFunction, (void *) ts);CHKERRQ(ierr);
7460       ierr = MatFDColoringSetFromOptions(color);CHKERRQ(ierr);
7461       ierr = MatFDColoringSetUp(B, iscoloring, color);CHKERRQ(ierr);
7462       ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr);
7463     }
7464     ierr = PetscObjectCompose((PetscObject) B, "TSMatFDColoring", (PetscObject) color);CHKERRQ(ierr);
7465     ierr = PetscObjectDereference((PetscObject) color);CHKERRQ(ierr);
7466   }
7467   ierr = TSGetSNES(ts, &snes);CHKERRQ(ierr);
7468   ierr = MatFDColoringApply(B, color, U, snes);CHKERRQ(ierr);
7469   if (J != B) {
7470     ierr = MatAssemblyBegin(J, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
7471     ierr = MatAssemblyEnd(J, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
7472   }
7473   PetscFunctionReturn(0);
7474 }
7475 
7476 /*@
7477     TSSetFunctionDomainError - Set the function testing if the current state vector is valid
7478 
7479     Input Parameters:
7480     ts - the TS context
7481     func - function called within TSFunctionDomainError
7482 
7483     Level: intermediate
7484 
7485 .keywords: TS, state, domain
7486 .seealso: TSAdaptCheckStage(), TSFunctionDomainError()
7487 @*/
7488 
7489 PetscErrorCode TSSetFunctionDomainError(TS ts, PetscErrorCode (*func)(TS,PetscReal,Vec,PetscBool*))
7490 {
7491   PetscFunctionBegin;
7492   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
7493   ts->functiondomainerror = func;
7494   PetscFunctionReturn(0);
7495 }
7496 
7497 /*@
7498     TSFunctionDomainError - Check if the current state is valid
7499 
7500     Input Parameters:
7501     ts - the TS context
7502     stagetime - time of the simulation
7503     Y - state vector to check.
7504 
7505     Output Parameter:
7506     accept - Set to PETSC_FALSE if the current state vector is valid.
7507 
7508     Note:
7509     This function should be used to ensure the state is in a valid part of the space.
7510     For example, one can ensure here all values are positive.
7511 
7512     Level: advanced
7513 @*/
7514 PetscErrorCode TSFunctionDomainError(TS ts,PetscReal stagetime,Vec Y,PetscBool* accept)
7515 {
7516   PetscFunctionBegin;
7517   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
7518   *accept = PETSC_TRUE;
7519   if (ts->functiondomainerror) {
7520     PetscStackCallStandard((*ts->functiondomainerror),(ts,stagetime,Y,accept));
7521   }
7522   PetscFunctionReturn(0);
7523 }
7524 
7525 /*@C
7526   TSClone - This function clones a time step object.
7527 
7528   Collective on MPI_Comm
7529 
7530   Input Parameter:
7531 . tsin    - The input TS
7532 
7533   Output Parameter:
7534 . tsout   - The output TS (cloned)
7535 
7536   Notes:
7537   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.
7538 
7539   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); TSSetSNES(ts,snes_dup);
7540 
7541   Level: developer
7542 
7543 .keywords: TS, clone
7544 .seealso: TSCreate(), TSSetType(), TSSetUp(), TSDestroy(), TSSetProblemType()
7545 @*/
7546 PetscErrorCode  TSClone(TS tsin, TS *tsout)
7547 {
7548   TS             t;
7549   PetscErrorCode ierr;
7550   SNES           snes_start;
7551   DM             dm;
7552   TSType         type;
7553 
7554   PetscFunctionBegin;
7555   PetscValidPointer(tsin,1);
7556   *tsout = NULL;
7557 
7558   ierr = PetscHeaderCreate(t, TS_CLASSID, "TS", "Time stepping", "TS", PetscObjectComm((PetscObject)tsin), TSDestroy, TSView);CHKERRQ(ierr);
7559 
7560   /* General TS description */
7561   t->numbermonitors    = 0;
7562   t->setupcalled       = 0;
7563   t->ksp_its           = 0;
7564   t->snes_its          = 0;
7565   t->nwork             = 0;
7566   t->rhsjacobian.time  = -1e20;
7567   t->rhsjacobian.scale = 1.;
7568   t->ijacobian.shift   = 1.;
7569 
7570   ierr = TSGetSNES(tsin,&snes_start);CHKERRQ(ierr);
7571   ierr = TSSetSNES(t,snes_start);CHKERRQ(ierr);
7572 
7573   ierr = TSGetDM(tsin,&dm);CHKERRQ(ierr);
7574   ierr = TSSetDM(t,dm);CHKERRQ(ierr);
7575 
7576   t->adapt = tsin->adapt;
7577   ierr = PetscObjectReference((PetscObject)t->adapt);CHKERRQ(ierr);
7578 
7579   t->trajectory = tsin->trajectory;
7580   ierr = PetscObjectReference((PetscObject)t->trajectory);CHKERRQ(ierr);
7581 
7582   t->event = tsin->event;
7583   if (t->event) t->event->refct++;
7584 
7585   t->problem_type      = tsin->problem_type;
7586   t->ptime             = tsin->ptime;
7587   t->ptime_prev        = tsin->ptime_prev;
7588   t->time_step         = tsin->time_step;
7589   t->max_time          = tsin->max_time;
7590   t->steps             = tsin->steps;
7591   t->max_steps         = tsin->max_steps;
7592   t->equation_type     = tsin->equation_type;
7593   t->atol              = tsin->atol;
7594   t->rtol              = tsin->rtol;
7595   t->max_snes_failures = tsin->max_snes_failures;
7596   t->max_reject        = tsin->max_reject;
7597   t->errorifstepfailed = tsin->errorifstepfailed;
7598 
7599   ierr = TSGetType(tsin,&type);CHKERRQ(ierr);
7600   ierr = TSSetType(t,type);CHKERRQ(ierr);
7601 
7602   t->vec_sol           = NULL;
7603 
7604   t->cfltime          = tsin->cfltime;
7605   t->cfltime_local    = tsin->cfltime_local;
7606   t->exact_final_time = tsin->exact_final_time;
7607 
7608   ierr = PetscMemcpy(t->ops,tsin->ops,sizeof(struct _TSOps));CHKERRQ(ierr);
7609 
7610   if (((PetscObject)tsin)->fortran_func_pointers) {
7611     PetscInt i;
7612     ierr = PetscMalloc((10)*sizeof(void(*)(void)),&((PetscObject)t)->fortran_func_pointers);CHKERRQ(ierr);
7613     for (i=0; i<10; i++) {
7614       ((PetscObject)t)->fortran_func_pointers[i] = ((PetscObject)tsin)->fortran_func_pointers[i];
7615     }
7616   }
7617   *tsout = t;
7618   PetscFunctionReturn(0);
7619 }
7620 
7621 static PetscErrorCode RHSWrapperFunction_TSRHSJacobianTest(void* ctx,Vec x,Vec y)
7622 {
7623   PetscErrorCode ierr;
7624   TS             ts = (TS) ctx;
7625 
7626   PetscFunctionBegin;
7627   ierr = TSComputeRHSFunction(ts,0,x,y);CHKERRQ(ierr);
7628   PetscFunctionReturn(0);
7629 }
7630 
7631 /*@
7632     TSRHSJacobianTest - Compares the multiply routine provided to the MATSHELL with differencing on the TS given RHS function.
7633 
7634    Logically Collective on TS and Mat
7635 
7636     Input Parameters:
7637     TS - the time stepping routine
7638 
7639    Output Parameter:
7640 .   flg - PETSC_TRUE if the multiply is likely correct
7641 
7642    Options Database:
7643  .   -ts_rhs_jacobian_test_mult -mat_shell_test_mult_view - run the test at each timestep of the integrator
7644 
7645    Level: advanced
7646 
7647    Notes:
7648     This only works for problems defined only the RHS function and Jacobian NOT IFunction and IJacobian
7649 
7650 .seealso: MatCreateShell(), MatShellGetContext(), MatShellGetOperation(), MatShellTestMultTranspose(), TSRHSJacobianTestTranspose()
7651 @*/
7652 PetscErrorCode  TSRHSJacobianTest(TS ts,PetscBool *flg)
7653 {
7654   Mat            J,B;
7655   PetscErrorCode ierr;
7656   TSRHSJacobian  func;
7657   void*          ctx;
7658 
7659   PetscFunctionBegin;
7660   ierr = TSGetRHSJacobian(ts,&J,&B,&func,&ctx);CHKERRQ(ierr);
7661   ierr = (*func)(ts,0.0,ts->vec_sol,J,B,ctx);CHKERRQ(ierr);
7662   ierr = MatShellTestMult(J,RHSWrapperFunction_TSRHSJacobianTest,ts->vec_sol,ts,flg);CHKERRQ(ierr);
7663   PetscFunctionReturn(0);
7664 }
7665 
7666 /*@C
7667     TSRHSJacobianTestTranspose - Compares the multiply transpose routine provided to the MATSHELL with differencing on the TS given RHS function.
7668 
7669    Logically Collective on TS and Mat
7670 
7671     Input Parameters:
7672     TS - the time stepping routine
7673 
7674    Output Parameter:
7675 .   flg - PETSC_TRUE if the multiply is likely correct
7676 
7677    Options Database:
7678 .   -ts_rhs_jacobian_test_mult_transpose -mat_shell_test_mult_transpose_view - run the test at each timestep of the integrator
7679 
7680    Notes:
7681     This only works for problems defined only the RHS function and Jacobian NOT IFunction and IJacobian
7682 
7683    Level: advanced
7684 
7685 .seealso: MatCreateShell(), MatShellGetContext(), MatShellGetOperation(), MatShellTestMultTranspose(), TSRHSJacobianTest()
7686 @*/
7687 PetscErrorCode  TSRHSJacobianTestTranspose(TS ts,PetscBool *flg)
7688 {
7689   Mat            J,B;
7690   PetscErrorCode ierr;
7691   void           *ctx;
7692   TSRHSJacobian  func;
7693 
7694   PetscFunctionBegin;
7695   ierr = TSGetRHSJacobian(ts,&J,&B,&func,&ctx);CHKERRQ(ierr);
7696   ierr = (*func)(ts,0.0,ts->vec_sol,J,B,ctx);CHKERRQ(ierr);
7697   ierr = MatShellTestMultTranspose(J,RHSWrapperFunction_TSRHSJacobianTest,ts->vec_sol,ts,flg);CHKERRQ(ierr);
7698   PetscFunctionReturn(0);
7699 }
7700 
7701 /*@
7702   TSSetUseSplitRHSFunction - Use the split RHSFunction when a multirate method is used.
7703 
7704   Logically collective
7705 
7706   Input Parameter:
7707 +  ts - timestepping context
7708 -  use_splitrhsfunction - PETSC_TRUE indicates that the split RHSFunction will be used
7709 
7710   Options Database:
7711 .   -ts_use_splitrhsfunction - <true,false>
7712 
7713   Notes:
7714     This is only useful for multirate methods
7715 
7716   Level: intermediate
7717 
7718 .seealso: TSGetUseSplitRHSFunction()
7719 @*/
7720 PetscErrorCode TSSetUseSplitRHSFunction(TS ts, PetscBool use_splitrhsfunction)
7721 {
7722   PetscFunctionBegin;
7723   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
7724   ts->use_splitrhsfunction = use_splitrhsfunction;
7725   PetscFunctionReturn(0);
7726 }
7727 
7728 /*@
7729   TSGetUseSplitRHSFunction - Gets whether to use the split RHSFunction when a multirate method is used.
7730 
7731   Not collective
7732 
7733   Input Parameter:
7734 .  ts - timestepping context
7735 
7736   Output Parameter:
7737 .  use_splitrhsfunction - PETSC_TRUE indicates that the split RHSFunction will be used
7738 
7739   Level: intermediate
7740 
7741 .seealso: TSSetUseSplitRHSFunction()
7742 @*/
7743 PetscErrorCode TSGetUseSplitRHSFunction(TS ts, PetscBool *use_splitrhsfunction)
7744 {
7745   PetscFunctionBegin;
7746   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
7747   *use_splitrhsfunction = ts->use_splitrhsfunction;
7748   PetscFunctionReturn(0);
7749 }
7750