xref: /petsc/src/ts/interface/ts.c (revision f3b211e446544ef617c96b3e399d80b808a9dc01)
1 
2 #include <petsc-private/tsimpl.h>        /*I "petscts.h"  I*/
3 #include <petscdmshell.h>
4 #include <petscdmda.h>
5 #include <petscviewer.h>
6 #include <petscdraw.h>
7 
8 /* Logging support */
9 PetscClassId  TS_CLASSID, DMTS_CLASSID;
10 PetscLogEvent TS_Step, TS_PseudoComputeTimeStep, TS_FunctionEval, TS_JacobianEval;
11 
12 const char *const TSExactFinalTimeOptions[] = {"STEPOVER","INTERPOLATE","MATCHSTEP","TSExactFinalTimeOption","TS_EXACTFINALTIME_",0};
13 
14 #undef __FUNCT__
15 #define __FUNCT__ "TSSetTypeFromOptions"
16 /*
17   TSSetTypeFromOptions - Sets the type of ts from user options.
18 
19   Collective on TS
20 
21   Input Parameter:
22 . ts - The ts
23 
24   Level: intermediate
25 
26 .keywords: TS, set, options, database, type
27 .seealso: TSSetFromOptions(), TSSetType()
28 */
29 static PetscErrorCode TSSetTypeFromOptions(TS ts)
30 {
31   PetscBool      opt;
32   const char     *defaultType;
33   char           typeName[256];
34   PetscErrorCode ierr;
35 
36   PetscFunctionBegin;
37   if (((PetscObject)ts)->type_name) defaultType = ((PetscObject)ts)->type_name;
38   else defaultType = TSEULER;
39 
40   if (!TSRegisterAllCalled) {ierr = TSRegisterAll(NULL);CHKERRQ(ierr);}
41   ierr = PetscOptionsList("-ts_type", "TS method"," TSSetType", TSList, defaultType, typeName, 256, &opt);CHKERRQ(ierr);
42   if (opt) {
43     ierr = TSSetType(ts, typeName);CHKERRQ(ierr);
44   } else {
45     ierr = TSSetType(ts, defaultType);CHKERRQ(ierr);
46   }
47   PetscFunctionReturn(0);
48 }
49 
50 struct _n_TSMonitorDrawCtx {
51   PetscViewer viewer;
52   Vec         initialsolution;
53   PetscBool   showinitial;
54   PetscInt    howoften;  /* when > 0 uses step % howoften, when negative only final solution plotted */
55   PetscBool   showtimestepandtime;
56   int         color;
57 };
58 
59 #undef __FUNCT__
60 #define __FUNCT__ "TSSetFromOptions"
61 /*@
62    TSSetFromOptions - Sets various TS parameters from user options.
63 
64    Collective on TS
65 
66    Input Parameter:
67 .  ts - the TS context obtained from TSCreate()
68 
69    Options Database Keys:
70 +  -ts_type <type> - TSEULER, TSBEULER, TSSUNDIALS, TSPSEUDO, TSCN, TSRK, TSTHETA, TSGL, TSSSP
71 .  -ts_max_steps maxsteps - maximum number of time-steps to take
72 .  -ts_final_time time - maximum time to compute to
73 .  -ts_dt dt - initial time step
74 .  -ts_monitor - print information at each timestep
75 .  -ts_monitor_lg_timestep - Monitor timestep size graphically
76 .  -ts_monitor_lg_solution - Monitor solution graphically
77 .  -ts_monitor_lg_error - Monitor error graphically
78 .  -ts_monitor_lg_snes_iterations - Monitor number nonlinear iterations for each timestep graphically
79 .  -ts_monitor_lg_ksp_iterations - Monitor number nonlinear iterations for each timestep graphically
80 .  -ts_monitor_sp_eig - Monitor eigenvalues of linearized operator graphically
81 .  -ts_monitor_draw_solution - Monitor solution graphically
82 .  -ts_monitor_draw_solution_phase - Monitor solution graphically with phase diagram
83 .  -ts_monitor_draw_error - Monitor error graphically
84 .  -ts_monitor_solution_binary <filename> - Save each solution to a binary file
85 -  -ts_monitor_solution_vtk <filename.vts> - Save each time step to a binary file, use filename-%%03D.vts
86 
87    Developer Note: We should unify all the -ts_monitor options in the way that -xxx_view has been unified
88 
89    Level: beginner
90 
91 .keywords: TS, timestep, set, options, database
92 
93 .seealso: TSGetType()
94 @*/
95 PetscErrorCode  TSSetFromOptions(TS ts)
96 {
97   PetscBool              opt,flg;
98   PetscErrorCode         ierr;
99   PetscViewer            monviewer;
100   char                   monfilename[PETSC_MAX_PATH_LEN];
101   SNES                   snes;
102   TSAdapt                adapt;
103   PetscReal              time_step;
104   TSExactFinalTimeOption eftopt;
105   char                   dir[16];
106 
107   PetscFunctionBegin;
108   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
109   ierr = PetscObjectOptionsBegin((PetscObject)ts);CHKERRQ(ierr);
110   /* Handle TS type options */
111   ierr = TSSetTypeFromOptions(ts);CHKERRQ(ierr);
112 
113   /* Handle generic TS options */
114   ierr = PetscOptionsInt("-ts_max_steps","Maximum number of time steps","TSSetDuration",ts->max_steps,&ts->max_steps,NULL);CHKERRQ(ierr);
115   ierr = PetscOptionsReal("-ts_final_time","Time to run to","TSSetDuration",ts->max_time,&ts->max_time,NULL);CHKERRQ(ierr);
116   ierr = PetscOptionsReal("-ts_init_time","Initial time","TSSetTime",ts->ptime,&ts->ptime,NULL);CHKERRQ(ierr);
117   ierr = PetscOptionsReal("-ts_dt","Initial time step","TSSetTimeStep",ts->time_step,&time_step,&flg);CHKERRQ(ierr);
118   if (flg) {
119     ierr = TSSetTimeStep(ts,time_step);CHKERRQ(ierr);
120   }
121   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);
122   if (flg) {ierr = TSSetExactFinalTime(ts,eftopt);CHKERRQ(ierr);}
123   ierr = PetscOptionsInt("-ts_max_snes_failures","Maximum number of nonlinear solve failures","TSSetMaxSNESFailures",ts->max_snes_failures,&ts->max_snes_failures,NULL);CHKERRQ(ierr);
124   ierr = PetscOptionsInt("-ts_max_reject","Maximum number of step rejections before step fails","TSSetMaxStepRejections",ts->max_reject,&ts->max_reject,NULL);CHKERRQ(ierr);
125   ierr = PetscOptionsBool("-ts_error_if_step_fails","Error if no step succeeds","TSSetErrorIfStepFails",ts->errorifstepfailed,&ts->errorifstepfailed,NULL);CHKERRQ(ierr);
126   ierr = PetscOptionsReal("-ts_rtol","Relative tolerance for local truncation error","TSSetTolerances",ts->rtol,&ts->rtol,NULL);CHKERRQ(ierr);
127   ierr = PetscOptionsReal("-ts_atol","Absolute tolerance for local truncation error","TSSetTolerances",ts->atol,&ts->atol,NULL);CHKERRQ(ierr);
128 
129   /* Monitor options */
130   ierr = PetscOptionsString("-ts_monitor","Monitor timestep size","TSMonitorDefault","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
131   if (flg) {
132     ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ts),monfilename,&monviewer);CHKERRQ(ierr);
133     ierr = TSMonitorSet(ts,TSMonitorDefault,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
134   }
135   ierr = PetscOptionsString("-ts_monitor_python","Use Python function","TSMonitorSet",0,monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
136   if (flg) {ierr = PetscPythonMonitorSet((PetscObject)ts,monfilename);CHKERRQ(ierr);}
137 
138   ierr = PetscOptionsName("-ts_monitor_lg_timestep","Monitor timestep size graphically","TSMonitorLGTimeStep",&opt);CHKERRQ(ierr);
139   if (opt) {
140     TSMonitorLGCtx ctx;
141     PetscInt       howoften = 1;
142 
143     ierr = PetscOptionsInt("-ts_monitor_lg_timestep","Monitor timestep size graphically","TSMonitorLGTimeStep",howoften,&howoften,NULL);CHKERRQ(ierr);
144     ierr = TSMonitorLGCtxCreate(PetscObjectComm((PetscObject)ts),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
145     ierr = TSMonitorSet(ts,TSMonitorLGTimeStep,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
146   }
147   ierr = PetscOptionsName("-ts_monitor_lg_solution","Monitor solution graphically","TSMonitorLGSolution",&opt);CHKERRQ(ierr);
148   if (opt) {
149     TSMonitorLGCtx ctx;
150     PetscInt       howoften = 1;
151 
152     ierr = PetscOptionsInt("-ts_monitor_lg_solution","Monitor solution graphically","TSMonitorLGSolution",howoften,&howoften,NULL);CHKERRQ(ierr);
153     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,600,400,howoften,&ctx);CHKERRQ(ierr);
154     ierr = TSMonitorSet(ts,TSMonitorLGSolution,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
155   }
156   ierr = PetscOptionsName("-ts_monitor_lg_error","Monitor error graphically","TSMonitorLGError",&opt);CHKERRQ(ierr);
157   if (opt) {
158     TSMonitorLGCtx ctx;
159     PetscInt       howoften = 1;
160 
161     ierr = PetscOptionsInt("-ts_monitor_lg_error","Monitor error graphically","TSMonitorLGError",howoften,&howoften,NULL);CHKERRQ(ierr);
162     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,600,400,howoften,&ctx);CHKERRQ(ierr);
163     ierr = TSMonitorSet(ts,TSMonitorLGError,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
164   }
165   ierr = PetscOptionsName("-ts_monitor_lg_snes_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGSNESIterations",&opt);CHKERRQ(ierr);
166   if (opt) {
167     TSMonitorLGCtx ctx;
168     PetscInt       howoften = 1;
169 
170     ierr = PetscOptionsInt("-ts_monitor_lg_snes_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGSNESIterations",howoften,&howoften,NULL);CHKERRQ(ierr);
171     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
172     ierr = TSMonitorSet(ts,TSMonitorLGSNESIterations,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
173   }
174   ierr = PetscOptionsName("-ts_monitor_lg_ksp_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGKSPIterations",&opt);CHKERRQ(ierr);
175   if (opt) {
176     TSMonitorLGCtx ctx;
177     PetscInt       howoften = 1;
178 
179     ierr = PetscOptionsInt("-ts_monitor_lg_ksp_iterations","Monitor number nonlinear iterations for each timestep graphically","TSMonitorLGKSPIterations",howoften,&howoften,NULL);CHKERRQ(ierr);
180     ierr = TSMonitorLGCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,howoften,&ctx);CHKERRQ(ierr);
181     ierr = TSMonitorSet(ts,TSMonitorLGKSPIterations,ctx,(PetscErrorCode (*)(void**))TSMonitorLGCtxDestroy);CHKERRQ(ierr);
182   }
183   ierr = PetscOptionsName("-ts_monitor_sp_eig","Monitor eigenvalues of linearized operator graphically","TSMonitorSPEig",&opt);CHKERRQ(ierr);
184   if (opt) {
185     TSMonitorSPEigCtx ctx;
186     PetscInt          howoften = 1;
187 
188     ierr = PetscOptionsInt("-ts_monitor_sp_eig","Monitor eigenvalues of linearized operator graphically","TSMonitorSPEig",howoften,&howoften,NULL);CHKERRQ(ierr);
189     ierr = TSMonitorSPEigCtxCreate(PETSC_COMM_SELF,0,0,PETSC_DECIDE,PETSC_DECIDE,600,400,howoften,&ctx);CHKERRQ(ierr);
190     ierr = TSMonitorSet(ts,TSMonitorSPEig,ctx,(PetscErrorCode (*)(void**))TSMonitorSPEigCtxDestroy);CHKERRQ(ierr);
191   }
192   opt  = PETSC_FALSE;
193   ierr = PetscOptionsName("-ts_monitor_draw_solution","Monitor solution graphically","TSMonitorDrawSolution",&opt);CHKERRQ(ierr);
194   if (opt) {
195     TSMonitorDrawCtx ctx;
196     PetscInt         howoften = 1;
197 
198     ierr = PetscOptionsInt("-ts_monitor_draw_solution","Monitor solution graphically","TSMonitorDrawSolution",howoften,&howoften,NULL);CHKERRQ(ierr);
199     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,0,PETSC_DECIDE,PETSC_DECIDE,600,400,howoften,&ctx);CHKERRQ(ierr);
200     ierr = TSMonitorSet(ts,TSMonitorDrawSolution,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
201   }
202   opt  = PETSC_FALSE;
203   ierr = PetscOptionsName("-ts_monitor_draw_solution_phase","Monitor solution graphically","TSMonitorDrawSolutionPhase",&opt);CHKERRQ(ierr);
204   if (opt) {
205     TSMonitorDrawCtx ctx;
206     PetscReal        bounds[4];
207     PetscInt         n = 4;
208     PetscDraw        draw;
209 
210     ierr = PetscOptionsRealArray("-ts_monitor_draw_solution_phase","Monitor solution graphically","TSMonitorDrawSolutionPhase",bounds,&n,NULL);CHKERRQ(ierr);
211     if (n != 4) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Must provide bounding box of phase field");
212     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,0,PETSC_DECIDE,PETSC_DECIDE,600,400,1,&ctx);CHKERRQ(ierr);
213     ierr = PetscViewerDrawGetDraw(ctx->viewer,0,&draw);CHKERRQ(ierr);
214     ierr = PetscDrawClear(draw);CHKERRQ(ierr);
215     ierr = PetscDrawSetCoordinates(draw,bounds[0],bounds[1],bounds[2],bounds[3]);CHKERRQ(ierr);
216     ierr = TSMonitorSet(ts,TSMonitorDrawSolutionPhase,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
217   }
218   opt  = PETSC_FALSE;
219   ierr = PetscOptionsName("-ts_monitor_draw_error","Monitor error graphically","TSMonitorDrawError",&opt);CHKERRQ(ierr);
220   if (opt) {
221     TSMonitorDrawCtx ctx;
222     PetscInt         howoften = 1;
223 
224     ierr = PetscOptionsInt("-ts_monitor_draw_error","Monitor error graphically","TSMonitorDrawError",howoften,&howoften,NULL);CHKERRQ(ierr);
225     ierr = TSMonitorDrawCtxCreate(PetscObjectComm((PetscObject)ts),0,0,PETSC_DECIDE,PETSC_DECIDE,600,400,howoften,&ctx);CHKERRQ(ierr);
226     ierr = TSMonitorSet(ts,TSMonitorDrawError,ctx,(PetscErrorCode (*)(void**))TSMonitorDrawCtxDestroy);CHKERRQ(ierr);
227   }
228   opt  = PETSC_FALSE;
229   ierr = PetscOptionsString("-ts_monitor_solution_binary","Save each solution to a binary file","TSMonitorSolutionBinary",0,monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
230   if (flg) {
231     PetscViewer ctx;
232     if (monfilename[0]) {
233       ierr = PetscViewerBinaryOpen(PetscObjectComm((PetscObject)ts),monfilename,FILE_MODE_WRITE,&ctx);CHKERRQ(ierr);
234       ierr = TSMonitorSet(ts,TSMonitorSolutionBinary,ctx,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
235     } else {
236       ctx = PETSC_VIEWER_BINARY_(PetscObjectComm((PetscObject)ts));
237       ierr = TSMonitorSet(ts,TSMonitorSolutionBinary,ctx,(PetscErrorCode (*)(void**))NULL);CHKERRQ(ierr);
238     }
239   }
240   opt  = PETSC_FALSE;
241   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);
242   if (flg) {
243     const char *ptr,*ptr2;
244     char       *filetemplate;
245     if (!monfilename[0]) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"-ts_monitor_solution_vtk requires a file template, e.g. filename-%%03D.vts");
246     /* Do some cursory validation of the input. */
247     ierr = PetscStrstr(monfilename,"%",(char**)&ptr);CHKERRQ(ierr);
248     if (!ptr) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"-ts_monitor_solution_vtk requires a file template, e.g. filename-%%03D.vts");
249     for (ptr++; ptr && *ptr; ptr++) {
250       ierr = PetscStrchr("DdiouxX",*ptr,(char**)&ptr2);CHKERRQ(ierr);
251       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");
252       if (ptr2) break;
253     }
254     ierr = PetscStrallocpy(monfilename,&filetemplate);CHKERRQ(ierr);
255     ierr = TSMonitorSet(ts,TSMonitorSolutionVTK,filetemplate,(PetscErrorCode (*)(void**))TSMonitorSolutionVTKDestroy);CHKERRQ(ierr);
256   }
257 
258   ierr = PetscOptionsString("-ts_monitor_dmda_ray","Display a ray of the solution","None","y=0",dir,16,&flg);CHKERRQ(ierr);
259   if (flg) {
260     TSMonitorDMDARayCtx *rayctx;
261     int                 ray = 0;
262     DMDADirection       ddir;
263     DM                  da;
264     PetscMPIInt         rank;
265 
266     if (dir[1] != '=') SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Unknown ray %s",dir);
267     if (dir[0] == 'x') ddir = DMDA_X;
268     else if (dir[0] == 'y') ddir = DMDA_Y;
269     else SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Unknown ray %s",dir);
270     sscanf(dir+2,"%d",&ray);
271 
272     ierr = PetscInfo2(((PetscObject)ts),"Displaying DMDA ray %c = %D\n",dir[0],ray);CHKERRQ(ierr);
273     ierr = PetscNew(TSMonitorDMDARayCtx,&rayctx);CHKERRQ(ierr);
274     ierr = TSGetDM(ts,&da);CHKERRQ(ierr);
275     ierr = DMDAGetRay(da,ddir,ray,&rayctx->ray,&rayctx->scatter);CHKERRQ(ierr);
276     ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)ts),&rank);CHKERRQ(ierr);
277     if (!rank) {
278       ierr = PetscViewerDrawOpen(PETSC_COMM_SELF,0,0,0,0,600,300,&rayctx->viewer);CHKERRQ(ierr);
279     }
280     ierr = TSMonitorSet(ts,TSMonitorDMDARay,rayctx,TSMonitorDMDARayDestroy);CHKERRQ(ierr);
281   }
282 
283   ierr = TSGetTSAdapt(ts,&adapt);CHKERRQ(ierr);
284   ierr = TSAdaptSetFromOptions(adapt);CHKERRQ(ierr);
285 
286   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
287   if (ts->problem_type == TS_LINEAR) {ierr = SNESSetType(snes,SNESKSPONLY);CHKERRQ(ierr);}
288 
289   /* Handle specific TS options */
290   if (ts->ops->setfromoptions) {
291     ierr = (*ts->ops->setfromoptions)(ts);CHKERRQ(ierr);
292   }
293 
294   /* process any options handlers added with PetscObjectAddOptionsHandler() */
295   ierr = PetscObjectProcessOptionsHandlers((PetscObject)ts);CHKERRQ(ierr);
296   ierr = PetscOptionsEnd();CHKERRQ(ierr);
297   PetscFunctionReturn(0);
298 }
299 
300 #undef __FUNCT__
301 #undef __FUNCT__
302 #define __FUNCT__ "TSComputeRHSJacobian"
303 /*@
304    TSComputeRHSJacobian - Computes the Jacobian matrix that has been
305       set with TSSetRHSJacobian().
306 
307    Collective on TS and Vec
308 
309    Input Parameters:
310 +  ts - the TS context
311 .  t - current timestep
312 -  U - input vector
313 
314    Output Parameters:
315 +  A - Jacobian matrix
316 .  B - optional preconditioning matrix
317 -  flag - flag indicating matrix structure
318 
319    Notes:
320    Most users should not need to explicitly call this routine, as it
321    is used internally within the nonlinear solvers.
322 
323    See KSPSetOperators() for important information about setting the
324    flag parameter.
325 
326    Level: developer
327 
328 .keywords: SNES, compute, Jacobian, matrix
329 
330 .seealso:  TSSetRHSJacobian(), KSPSetOperators()
331 @*/
332 PetscErrorCode  TSComputeRHSJacobian(TS ts,PetscReal t,Vec U,Mat *A,Mat *B,MatStructure *flg)
333 {
334   PetscErrorCode ierr;
335   PetscInt       Ustate;
336   DM             dm;
337   DMTS           tsdm;
338   TSRHSJacobian  rhsjacobianfunc;
339   void           *ctx;
340   TSIJacobian    ijacobianfunc;
341 
342   PetscFunctionBegin;
343   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
344   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
345   PetscCheckSameComm(ts,1,U,3);
346   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
347   ierr = DMGetDMTS(dm,&tsdm);CHKERRQ(ierr);
348   ierr = DMTSGetRHSJacobian(dm,&rhsjacobianfunc,&ctx);CHKERRQ(ierr);
349   ierr = DMTSGetIJacobian(dm,&ijacobianfunc,NULL);CHKERRQ(ierr);
350   ierr = PetscObjectStateQuery((PetscObject)U,&Ustate);CHKERRQ(ierr);
351   if (ts->rhsjacobian.time == t && (ts->problem_type == TS_LINEAR || (ts->rhsjacobian.X == U && ts->rhsjacobian.Xstate == Ustate))) {
352     *flg = ts->rhsjacobian.mstructure;
353     PetscFunctionReturn(0);
354   }
355 
356   if (!rhsjacobianfunc && !ijacobianfunc) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSJacobian() and / or TSSetIJacobian()");
357 
358   if (rhsjacobianfunc) {
359     ierr = PetscLogEventBegin(TS_JacobianEval,ts,U,*A,*B);CHKERRQ(ierr);
360     *flg = DIFFERENT_NONZERO_PATTERN;
361     PetscStackPush("TS user Jacobian function");
362     ierr = (*rhsjacobianfunc)(ts,t,U,A,B,flg,ctx);CHKERRQ(ierr);
363     PetscStackPop;
364     ierr = PetscLogEventEnd(TS_JacobianEval,ts,U,*A,*B);CHKERRQ(ierr);
365     /* make sure user returned a correct Jacobian and preconditioner */
366     PetscValidHeaderSpecific(*A,MAT_CLASSID,4);
367     PetscValidHeaderSpecific(*B,MAT_CLASSID,5);
368   } else {
369     ierr = MatZeroEntries(*A);CHKERRQ(ierr);
370     if (*A != *B) {ierr = MatZeroEntries(*B);CHKERRQ(ierr);}
371     *flg = SAME_NONZERO_PATTERN;
372   }
373   ts->rhsjacobian.time       = t;
374   ts->rhsjacobian.X          = U;
375   ierr                       = PetscObjectStateQuery((PetscObject)U,&ts->rhsjacobian.Xstate);CHKERRQ(ierr);
376   ts->rhsjacobian.mstructure = *flg;
377   PetscFunctionReturn(0);
378 }
379 
380 #undef __FUNCT__
381 #define __FUNCT__ "TSComputeRHSFunction"
382 /*@
383    TSComputeRHSFunction - Evaluates the right-hand-side function.
384 
385    Collective on TS and Vec
386 
387    Input Parameters:
388 +  ts - the TS context
389 .  t - current time
390 -  U - state vector
391 
392    Output Parameter:
393 .  y - right hand side
394 
395    Note:
396    Most users should not need to explicitly call this routine, as it
397    is used internally within the nonlinear solvers.
398 
399    Level: developer
400 
401 .keywords: TS, compute
402 
403 .seealso: TSSetRHSFunction(), TSComputeIFunction()
404 @*/
405 PetscErrorCode TSComputeRHSFunction(TS ts,PetscReal t,Vec U,Vec y)
406 {
407   PetscErrorCode ierr;
408   TSRHSFunction  rhsfunction;
409   TSIFunction    ifunction;
410   void           *ctx;
411   DM             dm;
412 
413   PetscFunctionBegin;
414   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
415   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
416   PetscValidHeaderSpecific(y,VEC_CLASSID,4);
417   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
418   ierr = DMTSGetRHSFunction(dm,&rhsfunction,&ctx);CHKERRQ(ierr);
419   ierr = DMTSGetIFunction(dm,&ifunction,NULL);CHKERRQ(ierr);
420 
421   if (!rhsfunction && !ifunction) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSFunction() and / or TSSetIFunction()");
422 
423   ierr = PetscLogEventBegin(TS_FunctionEval,ts,U,y,0);CHKERRQ(ierr);
424   if (rhsfunction) {
425     PetscStackPush("TS user right-hand-side function");
426     ierr = (*rhsfunction)(ts,t,U,y,ctx);CHKERRQ(ierr);
427     PetscStackPop;
428   } else {
429     ierr = VecZeroEntries(y);CHKERRQ(ierr);
430   }
431 
432   ierr = PetscLogEventEnd(TS_FunctionEval,ts,U,y,0);CHKERRQ(ierr);
433   PetscFunctionReturn(0);
434 }
435 
436 #undef __FUNCT__
437 #define __FUNCT__ "TSComputeSolutionFunction"
438 /*@
439    TSComputeSolutionFunction - Evaluates the solution function.
440 
441    Collective on TS and Vec
442 
443    Input Parameters:
444 +  ts - the TS context
445 -  t - current time
446 
447    Output Parameter:
448 .  U - the solution
449 
450    Note:
451    Most users should not need to explicitly call this routine, as it
452    is used internally within the nonlinear solvers.
453 
454    Level: developer
455 
456 .keywords: TS, compute
457 
458 .seealso: TSSetSolutionFunction(), TSSetRHSFunction(), TSComputeIFunction()
459 @*/
460 PetscErrorCode TSComputeSolutionFunction(TS ts,PetscReal t,Vec U)
461 {
462   PetscErrorCode     ierr;
463   TSSolutionFunction solutionfunction;
464   void               *ctx;
465   DM                 dm;
466 
467   PetscFunctionBegin;
468   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
469   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
470   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
471   ierr = DMTSGetSolutionFunction(dm,&solutionfunction,&ctx);CHKERRQ(ierr);
472 
473   if (solutionfunction) {
474     PetscStackPush("TS user solution function");
475     ierr = (*solutionfunction)(ts,t,U,ctx);CHKERRQ(ierr);
476     PetscStackPop;
477   }
478   PetscFunctionReturn(0);
479 }
480 #undef __FUNCT__
481 #define __FUNCT__ "TSComputeForcingFunction"
482 /*@
483    TSComputeForcingFunction - Evaluates the forcing function.
484 
485    Collective on TS and Vec
486 
487    Input Parameters:
488 +  ts - the TS context
489 -  t - current time
490 
491    Output Parameter:
492 .  U - the function value
493 
494    Note:
495    Most users should not need to explicitly call this routine, as it
496    is used internally within the nonlinear solvers.
497 
498    Level: developer
499 
500 .keywords: TS, compute
501 
502 .seealso: TSSetSolutionFunction(), TSSetRHSFunction(), TSComputeIFunction()
503 @*/
504 PetscErrorCode TSComputeForcingFunction(TS ts,PetscReal t,Vec U)
505 {
506   PetscErrorCode     ierr, (*forcing)(TS,PetscReal,Vec,void*);
507   void               *ctx;
508   DM                 dm;
509 
510   PetscFunctionBegin;
511   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
512   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
513   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
514   ierr = DMTSGetForcingFunction(dm,&forcing,&ctx);CHKERRQ(ierr);
515 
516   if (forcing) {
517     PetscStackPush("TS user forcing function");
518     ierr = (*forcing)(ts,t,U,ctx);CHKERRQ(ierr);
519     PetscStackPop;
520   }
521   PetscFunctionReturn(0);
522 }
523 
524 #undef __FUNCT__
525 #define __FUNCT__ "TSGetRHSVec_Private"
526 static PetscErrorCode TSGetRHSVec_Private(TS ts,Vec *Frhs)
527 {
528   Vec            F;
529   PetscErrorCode ierr;
530 
531   PetscFunctionBegin;
532   *Frhs = NULL;
533   ierr  = TSGetIFunction(ts,&F,NULL,NULL);CHKERRQ(ierr);
534   if (!ts->Frhs) {
535     ierr = VecDuplicate(F,&ts->Frhs);CHKERRQ(ierr);
536   }
537   *Frhs = ts->Frhs;
538   PetscFunctionReturn(0);
539 }
540 
541 #undef __FUNCT__
542 #define __FUNCT__ "TSGetRHSMats_Private"
543 static PetscErrorCode TSGetRHSMats_Private(TS ts,Mat *Arhs,Mat *Brhs)
544 {
545   Mat            A,B;
546   PetscErrorCode ierr;
547 
548   PetscFunctionBegin;
549   ierr = TSGetIJacobian(ts,&A,&B,NULL,NULL);CHKERRQ(ierr);
550   if (Arhs) {
551     if (!ts->Arhs) {
552       ierr = MatDuplicate(A,MAT_DO_NOT_COPY_VALUES,&ts->Arhs);CHKERRQ(ierr);
553     }
554     *Arhs = ts->Arhs;
555   }
556   if (Brhs) {
557     if (!ts->Brhs) {
558       ierr = MatDuplicate(B,MAT_DO_NOT_COPY_VALUES,&ts->Brhs);CHKERRQ(ierr);
559     }
560     *Brhs = ts->Brhs;
561   }
562   PetscFunctionReturn(0);
563 }
564 
565 #undef __FUNCT__
566 #define __FUNCT__ "TSComputeIFunction"
567 /*@
568    TSComputeIFunction - Evaluates the DAE residual written in implicit form F(t,U,Udot)=0
569 
570    Collective on TS and Vec
571 
572    Input Parameters:
573 +  ts - the TS context
574 .  t - current time
575 .  U - state vector
576 .  Udot - time derivative of state vector
577 -  imex - flag indicates if the method is IMEX so that the RHSFunction should be kept separate
578 
579    Output Parameter:
580 .  Y - right hand side
581 
582    Note:
583    Most users should not need to explicitly call this routine, as it
584    is used internally within the nonlinear solvers.
585 
586    If the user did did not write their equations in implicit form, this
587    function recasts them in implicit form.
588 
589    Level: developer
590 
591 .keywords: TS, compute
592 
593 .seealso: TSSetIFunction(), TSComputeRHSFunction()
594 @*/
595 PetscErrorCode TSComputeIFunction(TS ts,PetscReal t,Vec U,Vec Udot,Vec Y,PetscBool imex)
596 {
597   PetscErrorCode ierr;
598   TSIFunction    ifunction;
599   TSRHSFunction  rhsfunction;
600   void           *ctx;
601   DM             dm;
602 
603   PetscFunctionBegin;
604   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
605   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
606   PetscValidHeaderSpecific(Udot,VEC_CLASSID,4);
607   PetscValidHeaderSpecific(Y,VEC_CLASSID,5);
608 
609   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
610   ierr = DMTSGetIFunction(dm,&ifunction,&ctx);CHKERRQ(ierr);
611   ierr = DMTSGetRHSFunction(dm,&rhsfunction,NULL);CHKERRQ(ierr);
612 
613   if (!rhsfunction && !ifunction) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSFunction() and / or TSSetIFunction()");
614 
615   ierr = PetscLogEventBegin(TS_FunctionEval,ts,U,Udot,Y);CHKERRQ(ierr);
616   if (ifunction) {
617     PetscStackPush("TS user implicit function");
618     ierr = (*ifunction)(ts,t,U,Udot,Y,ctx);CHKERRQ(ierr);
619     PetscStackPop;
620   }
621   if (imex) {
622     if (!ifunction) {
623       ierr = VecCopy(Udot,Y);CHKERRQ(ierr);
624     }
625   } else if (rhsfunction) {
626     if (ifunction) {
627       Vec Frhs;
628       ierr = TSGetRHSVec_Private(ts,&Frhs);CHKERRQ(ierr);
629       ierr = TSComputeRHSFunction(ts,t,U,Frhs);CHKERRQ(ierr);
630       ierr = VecAXPY(Y,-1,Frhs);CHKERRQ(ierr);
631     } else {
632       ierr = TSComputeRHSFunction(ts,t,U,Y);CHKERRQ(ierr);
633       ierr = VecAYPX(Y,-1,Udot);CHKERRQ(ierr);
634     }
635   }
636   ierr = PetscLogEventEnd(TS_FunctionEval,ts,U,Udot,Y);CHKERRQ(ierr);
637   PetscFunctionReturn(0);
638 }
639 
640 #undef __FUNCT__
641 #define __FUNCT__ "TSComputeIJacobian"
642 /*@
643    TSComputeIJacobian - Evaluates the Jacobian of the DAE
644 
645    Collective on TS and Vec
646 
647    Input
648       Input Parameters:
649 +  ts - the TS context
650 .  t - current timestep
651 .  U - state vector
652 .  Udot - time derivative of state vector
653 .  shift - shift to apply, see note below
654 -  imex - flag indicates if the method is IMEX so that the RHSJacobian should be kept separate
655 
656    Output Parameters:
657 +  A - Jacobian matrix
658 .  B - optional preconditioning matrix
659 -  flag - flag indicating matrix structure
660 
661    Notes:
662    If F(t,U,Udot)=0 is the DAE, the required Jacobian is
663 
664    dF/dU + shift*dF/dUdot
665 
666    Most users should not need to explicitly call this routine, as it
667    is used internally within the nonlinear solvers.
668 
669    Level: developer
670 
671 .keywords: TS, compute, Jacobian, matrix
672 
673 .seealso:  TSSetIJacobian()
674 @*/
675 PetscErrorCode TSComputeIJacobian(TS ts,PetscReal t,Vec U,Vec Udot,PetscReal shift,Mat *A,Mat *B,MatStructure *flg,PetscBool imex)
676 {
677   PetscInt       Ustate, Udotstate;
678   PetscErrorCode ierr;
679   TSIJacobian    ijacobian;
680   TSRHSJacobian  rhsjacobian;
681   DM             dm;
682   void           *ctx;
683 
684   PetscFunctionBegin;
685   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
686   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
687   PetscValidHeaderSpecific(Udot,VEC_CLASSID,4);
688   PetscValidPointer(A,6);
689   PetscValidHeaderSpecific(*A,MAT_CLASSID,6);
690   PetscValidPointer(B,7);
691   PetscValidHeaderSpecific(*B,MAT_CLASSID,7);
692   PetscValidPointer(flg,8);
693 
694   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
695   ierr = DMTSGetIJacobian(dm,&ijacobian,&ctx);CHKERRQ(ierr);
696   ierr = DMTSGetRHSJacobian(dm,&rhsjacobian,NULL);CHKERRQ(ierr);
697 
698   ierr = PetscObjectStateQuery((PetscObject)U,&Ustate);CHKERRQ(ierr);
699   ierr = PetscObjectStateQuery((PetscObject)Udot,&Udotstate);CHKERRQ(ierr);
700   if (ts->ijacobian.time == t && (ts->problem_type == TS_LINEAR || (ts->ijacobian.X == U && ts->ijacobian.Xstate == Ustate && ts->ijacobian.Xdot == Udot && ts->ijacobian.Xdotstate == Udotstate && ts->ijacobian.imex == imex))) {
701     *flg = ts->ijacobian.mstructure;
702     ierr = MatScale(*A, shift / ts->ijacobian.shift);CHKERRQ(ierr);
703     PetscFunctionReturn(0);
704   }
705 
706   if (!rhsjacobian && !ijacobian) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_USER,"Must call TSSetRHSJacobian() and / or TSSetIJacobian()");
707 
708   *flg = SAME_NONZERO_PATTERN;  /* In case we're solving a linear problem in which case it wouldn't get initialized below. */
709   ierr = PetscLogEventBegin(TS_JacobianEval,ts,U,*A,*B);CHKERRQ(ierr);
710   if (ijacobian) {
711     *flg = DIFFERENT_NONZERO_PATTERN;
712     PetscStackPush("TS user implicit Jacobian");
713     ierr = (*ijacobian)(ts,t,U,Udot,shift,A,B,flg,ctx);CHKERRQ(ierr);
714     PetscStackPop;
715     /* make sure user returned a correct Jacobian and preconditioner */
716     PetscValidHeaderSpecific(*A,MAT_CLASSID,4);
717     PetscValidHeaderSpecific(*B,MAT_CLASSID,5);
718   }
719   if (imex) {
720     if (!ijacobian) {  /* system was written as Udot = G(t,U) */
721       ierr = MatZeroEntries(*A);CHKERRQ(ierr);
722       ierr = MatShift(*A,shift);CHKERRQ(ierr);
723       if (*A != *B) {
724         ierr = MatZeroEntries(*B);CHKERRQ(ierr);
725         ierr = MatShift(*B,shift);CHKERRQ(ierr);
726       }
727       *flg = SAME_PRECONDITIONER;
728     }
729   } else {
730     if (!ijacobian) {
731       ierr = TSComputeRHSJacobian(ts,t,U,A,B,flg);CHKERRQ(ierr);
732       ierr = MatScale(*A,-1);CHKERRQ(ierr);
733       ierr = MatShift(*A,shift);CHKERRQ(ierr);
734       if (*A != *B) {
735         ierr = MatScale(*B,-1);CHKERRQ(ierr);
736         ierr = MatShift(*B,shift);CHKERRQ(ierr);
737       }
738     } else if (rhsjacobian) {
739       Mat          Arhs,Brhs;
740       MatStructure axpy,flg2 = DIFFERENT_NONZERO_PATTERN;
741       ierr = TSGetRHSMats_Private(ts,&Arhs,&Brhs);CHKERRQ(ierr);
742       ierr = TSComputeRHSJacobian(ts,t,U,&Arhs,&Brhs,&flg2);CHKERRQ(ierr);
743       axpy = (*flg == flg2) ? SAME_NONZERO_PATTERN : DIFFERENT_NONZERO_PATTERN;
744       ierr = MatAXPY(*A,-1,Arhs,axpy);CHKERRQ(ierr);
745       if (*A != *B) {
746         ierr = MatAXPY(*B,-1,Brhs,axpy);CHKERRQ(ierr);
747       }
748       *flg = PetscMin(*flg,flg2);
749     }
750   }
751 
752   ts->ijacobian.time = t;
753   ts->ijacobian.X    = U;
754   ts->ijacobian.Xdot = Udot;
755 
756   ierr = PetscObjectStateQuery((PetscObject)U,&ts->ijacobian.Xstate);CHKERRQ(ierr);
757   ierr = PetscObjectStateQuery((PetscObject)Udot,&ts->ijacobian.Xdotstate);CHKERRQ(ierr);
758 
759   ts->ijacobian.shift      = shift;
760   ts->ijacobian.imex       = imex;
761   ts->ijacobian.mstructure = *flg;
762 
763   ierr = PetscLogEventEnd(TS_JacobianEval,ts,U,*A,*B);CHKERRQ(ierr);
764   PetscFunctionReturn(0);
765 }
766 
767 #undef __FUNCT__
768 #define __FUNCT__ "TSSetRHSFunction"
769 /*@C
770     TSSetRHSFunction - Sets the routine for evaluating the function,
771     where U_t = G(t,u).
772 
773     Logically Collective on TS
774 
775     Input Parameters:
776 +   ts - the TS context obtained from TSCreate()
777 .   r - vector to put the computed right hand side (or NULL to have it created)
778 .   f - routine for evaluating the right-hand-side function
779 -   ctx - [optional] user-defined context for private data for the
780           function evaluation routine (may be NULL)
781 
782     Calling sequence of func:
783 $     func (TS ts,PetscReal t,Vec u,Vec F,void *ctx);
784 
785 +   t - current timestep
786 .   u - input vector
787 .   F - function vector
788 -   ctx - [optional] user-defined function context
789 
790     Level: beginner
791 
792 .keywords: TS, timestep, set, right-hand-side, function
793 
794 .seealso: TSSetRHSJacobian(), TSSetIJacobian()
795 @*/
796 PetscErrorCode  TSSetRHSFunction(TS ts,Vec r,PetscErrorCode (*f)(TS,PetscReal,Vec,Vec,void*),void *ctx)
797 {
798   PetscErrorCode ierr;
799   SNES           snes;
800   Vec            ralloc = NULL;
801   DM             dm;
802 
803   PetscFunctionBegin;
804   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
805   if (r) PetscValidHeaderSpecific(r,VEC_CLASSID,2);
806 
807   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
808   ierr = DMTSSetRHSFunction(dm,f,ctx);CHKERRQ(ierr);
809   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
810   if (!r && !ts->dm && ts->vec_sol) {
811     ierr = VecDuplicate(ts->vec_sol,&ralloc);CHKERRQ(ierr);
812     r    = ralloc;
813   }
814   ierr = SNESSetFunction(snes,r,SNESTSFormFunction,ts);CHKERRQ(ierr);
815   ierr = VecDestroy(&ralloc);CHKERRQ(ierr);
816   PetscFunctionReturn(0);
817 }
818 
819 #undef __FUNCT__
820 #define __FUNCT__ "TSSetSolutionFunction"
821 /*@C
822     TSSetSolutionFunction - Provide a function that computes the solution of the ODE or DAE
823 
824     Logically Collective on TS
825 
826     Input Parameters:
827 +   ts - the TS context obtained from TSCreate()
828 .   f - routine for evaluating the solution
829 -   ctx - [optional] user-defined context for private data for the
830           function evaluation routine (may be NULL)
831 
832     Calling sequence of func:
833 $     func (TS ts,PetscReal t,Vec u,void *ctx);
834 
835 +   t - current timestep
836 .   u - output vector
837 -   ctx - [optional] user-defined function context
838 
839     Notes:
840     This routine is used for testing accuracy of time integration schemes when you already know the solution.
841     If analytic solutions are not known for your system, consider using the Method of Manufactured Solutions to
842     create closed-form solutions with non-physical forcing terms.
843 
844     For low-dimensional problems solved in serial, such as small discrete systems, TSMonitorLGError() can be used to monitor the error history.
845 
846     Level: beginner
847 
848 .keywords: TS, timestep, set, right-hand-side, function
849 
850 .seealso: TSSetRHSJacobian(), TSSetIJacobian(), TSComputeSolutionFunction(), TSSetForcingFunction()
851 @*/
852 PetscErrorCode  TSSetSolutionFunction(TS ts,PetscErrorCode (*f)(TS,PetscReal,Vec,void*),void *ctx)
853 {
854   PetscErrorCode ierr;
855   DM             dm;
856 
857   PetscFunctionBegin;
858   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
859   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
860   ierr = DMTSSetSolutionFunction(dm,f,ctx);CHKERRQ(ierr);
861   PetscFunctionReturn(0);
862 }
863 
864 #undef __FUNCT__
865 #define __FUNCT__ "TSSetForcingFunction"
866 /*@C
867     TSSetForcingFunction - Provide a function that computes a forcing term for a ODE or PDE
868 
869     Logically Collective on TS
870 
871     Input Parameters:
872 +   ts - the TS context obtained from TSCreate()
873 .   f - routine for evaluating the forcing function
874 -   ctx - [optional] user-defined context for private data for the
875           function evaluation routine (may be NULL)
876 
877     Calling sequence of func:
878 $     func (TS ts,PetscReal t,Vec u,void *ctx);
879 
880 +   t - current timestep
881 .   u - output vector
882 -   ctx - [optional] user-defined function context
883 
884     Notes:
885     This routine is useful for testing accuracy of time integration schemes when using the Method of Manufactured Solutions to
886     create closed-form solutions with a non-physical forcing term.
887 
888     For low-dimensional problems solved in serial, such as small discrete systems, TSMonitorLGError() can be used to monitor the error history.
889 
890     Level: beginner
891 
892 .keywords: TS, timestep, set, right-hand-side, function
893 
894 .seealso: TSSetRHSJacobian(), TSSetIJacobian(), TSComputeSolutionFunction(), TSSetSolutionFunction()
895 @*/
896 PetscErrorCode  TSSetForcingFunction(TS ts,PetscErrorCode (*f)(TS,PetscReal,Vec,void*),void *ctx)
897 {
898   PetscErrorCode ierr;
899   DM             dm;
900 
901   PetscFunctionBegin;
902   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
903   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
904   ierr = DMTSSetForcingFunction(dm,f,ctx);CHKERRQ(ierr);
905   PetscFunctionReturn(0);
906 }
907 
908 #undef __FUNCT__
909 #define __FUNCT__ "TSSetRHSJacobian"
910 /*@C
911    TSSetRHSJacobian - Sets the function to compute the Jacobian of F,
912    where U_t = G(U,t), as well as the location to store the matrix.
913 
914    Logically Collective on TS
915 
916    Input Parameters:
917 +  ts  - the TS context obtained from TSCreate()
918 .  A   - Jacobian matrix
919 .  B   - preconditioner matrix (usually same as A)
920 .  f   - the Jacobian evaluation routine
921 -  ctx - [optional] user-defined context for private data for the
922          Jacobian evaluation routine (may be NULL)
923 
924    Calling sequence of func:
925 $     func (TS ts,PetscReal t,Vec u,Mat *A,Mat *B,MatStructure *flag,void *ctx);
926 
927 +  t - current timestep
928 .  u - input vector
929 .  A - matrix A, where U_t = A(t)u
930 .  B - preconditioner matrix, usually the same as A
931 .  flag - flag indicating information about the preconditioner matrix
932           structure (same as flag in KSPSetOperators())
933 -  ctx - [optional] user-defined context for matrix evaluation routine
934 
935    Notes:
936    See KSPSetOperators() for important information about setting the flag
937    output parameter in the routine func().  Be sure to read this information!
938 
939    The routine func() takes Mat * as the matrix arguments rather than Mat.
940    This allows the matrix evaluation routine to replace A and/or B with a
941    completely new matrix structure (not just different matrix elements)
942    when appropriate, for instance, if the nonzero structure is changing
943    throughout the global iterations.
944 
945    Level: beginner
946 
947 .keywords: TS, timestep, set, right-hand-side, Jacobian
948 
949 .seealso: SNESDefaultComputeJacobianColor(), TSSetRHSFunction()
950 
951 @*/
952 PetscErrorCode  TSSetRHSJacobian(TS ts,Mat A,Mat B,TSRHSJacobian f,void *ctx)
953 {
954   PetscErrorCode ierr;
955   SNES           snes;
956   DM             dm;
957   TSIJacobian    ijacobian;
958 
959   PetscFunctionBegin;
960   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
961   if (A) PetscValidHeaderSpecific(A,MAT_CLASSID,2);
962   if (B) PetscValidHeaderSpecific(B,MAT_CLASSID,3);
963   if (A) PetscCheckSameComm(ts,1,A,2);
964   if (B) PetscCheckSameComm(ts,1,B,3);
965 
966   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
967   ierr = DMTSSetRHSJacobian(dm,f,ctx);CHKERRQ(ierr);
968   ierr = DMTSGetIJacobian(dm,&ijacobian,NULL);CHKERRQ(ierr);
969 
970   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
971   if (!ijacobian) {
972     ierr = SNESSetJacobian(snes,A,B,SNESTSFormJacobian,ts);CHKERRQ(ierr);
973   }
974   if (A) {
975     ierr = PetscObjectReference((PetscObject)A);CHKERRQ(ierr);
976     ierr = MatDestroy(&ts->Arhs);CHKERRQ(ierr);
977 
978     ts->Arhs = A;
979   }
980   if (B) {
981     ierr = PetscObjectReference((PetscObject)B);CHKERRQ(ierr);
982     ierr = MatDestroy(&ts->Brhs);CHKERRQ(ierr);
983 
984     ts->Brhs = B;
985   }
986   PetscFunctionReturn(0);
987 }
988 
989 
990 #undef __FUNCT__
991 #define __FUNCT__ "TSSetIFunction"
992 /*@C
993    TSSetIFunction - Set the function to compute F(t,U,U_t) where F() = 0 is the DAE to be solved.
994 
995    Logically Collective on TS
996 
997    Input Parameters:
998 +  ts  - the TS context obtained from TSCreate()
999 .  r   - vector to hold the residual (or NULL to have it created internally)
1000 .  f   - the function evaluation routine
1001 -  ctx - user-defined context for private data for the function evaluation routine (may be NULL)
1002 
1003    Calling sequence of f:
1004 $  f(TS ts,PetscReal t,Vec u,Vec u_t,Vec F,ctx);
1005 
1006 +  t   - time at step/stage being solved
1007 .  u   - state vector
1008 .  u_t - time derivative of state vector
1009 .  F   - function vector
1010 -  ctx - [optional] user-defined context for matrix evaluation routine
1011 
1012    Important:
1013    The user MUST call either this routine, TSSetRHSFunction().  This routine must be used when not solving an ODE, for example a DAE.
1014 
1015    Level: beginner
1016 
1017 .keywords: TS, timestep, set, DAE, Jacobian
1018 
1019 .seealso: TSSetRHSJacobian(), TSSetRHSFunction(), TSSetIJacobian()
1020 @*/
1021 PetscErrorCode  TSSetIFunction(TS ts,Vec res,TSIFunction f,void *ctx)
1022 {
1023   PetscErrorCode ierr;
1024   SNES           snes;
1025   Vec            resalloc = NULL;
1026   DM             dm;
1027 
1028   PetscFunctionBegin;
1029   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1030   if (res) PetscValidHeaderSpecific(res,VEC_CLASSID,2);
1031 
1032   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1033   ierr = DMTSSetIFunction(dm,f,ctx);CHKERRQ(ierr);
1034 
1035   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1036   if (!res && !ts->dm && ts->vec_sol) {
1037     ierr = VecDuplicate(ts->vec_sol,&resalloc);CHKERRQ(ierr);
1038     res  = resalloc;
1039   }
1040   ierr = SNESSetFunction(snes,res,SNESTSFormFunction,ts);CHKERRQ(ierr);
1041   ierr = VecDestroy(&resalloc);CHKERRQ(ierr);
1042   PetscFunctionReturn(0);
1043 }
1044 
1045 #undef __FUNCT__
1046 #define __FUNCT__ "TSGetIFunction"
1047 /*@C
1048    TSGetIFunction - Returns the vector where the implicit residual is stored and the function/contex to compute it.
1049 
1050    Not Collective
1051 
1052    Input Parameter:
1053 .  ts - the TS context
1054 
1055    Output Parameter:
1056 +  r - vector to hold residual (or NULL)
1057 .  func - the function to compute residual (or NULL)
1058 -  ctx - the function context (or NULL)
1059 
1060    Level: advanced
1061 
1062 .keywords: TS, nonlinear, get, function
1063 
1064 .seealso: TSSetIFunction(), SNESGetFunction()
1065 @*/
1066 PetscErrorCode TSGetIFunction(TS ts,Vec *r,TSIFunction *func,void **ctx)
1067 {
1068   PetscErrorCode ierr;
1069   SNES           snes;
1070   DM             dm;
1071 
1072   PetscFunctionBegin;
1073   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1074   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1075   ierr = SNESGetFunction(snes,r,NULL,NULL);CHKERRQ(ierr);
1076   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1077   ierr = DMTSGetIFunction(dm,func,ctx);CHKERRQ(ierr);
1078   PetscFunctionReturn(0);
1079 }
1080 
1081 #undef __FUNCT__
1082 #define __FUNCT__ "TSGetRHSFunction"
1083 /*@C
1084    TSGetRHSFunction - Returns the vector where the right hand side is stored and the function/context to compute it.
1085 
1086    Not Collective
1087 
1088    Input Parameter:
1089 .  ts - the TS context
1090 
1091    Output Parameter:
1092 +  r - vector to hold computed right hand side (or NULL)
1093 .  func - the function to compute right hand side (or NULL)
1094 -  ctx - the function context (or NULL)
1095 
1096    Level: advanced
1097 
1098 .keywords: TS, nonlinear, get, function
1099 
1100 .seealso: TSSetRhsfunction(), SNESGetFunction()
1101 @*/
1102 PetscErrorCode TSGetRHSFunction(TS ts,Vec *r,TSRHSFunction *func,void **ctx)
1103 {
1104   PetscErrorCode ierr;
1105   SNES           snes;
1106   DM             dm;
1107 
1108   PetscFunctionBegin;
1109   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1110   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1111   ierr = SNESGetFunction(snes,r,NULL,NULL);CHKERRQ(ierr);
1112   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1113   ierr = DMTSGetRHSFunction(dm,func,ctx);CHKERRQ(ierr);
1114   PetscFunctionReturn(0);
1115 }
1116 
1117 #undef __FUNCT__
1118 #define __FUNCT__ "TSSetIJacobian"
1119 /*@C
1120    TSSetIJacobian - Set the function to compute the matrix dF/dU + a*dF/dU_t where F(t,U,U_t) is the function
1121         you provided with TSSetIFunction().
1122 
1123    Logically Collective on TS
1124 
1125    Input Parameters:
1126 +  ts  - the TS context obtained from TSCreate()
1127 .  A   - Jacobian matrix
1128 .  B   - preconditioning matrix for A (may be same as A)
1129 .  f   - the Jacobian evaluation routine
1130 -  ctx - user-defined context for private data for the Jacobian evaluation routine (may be NULL)
1131 
1132    Calling sequence of f:
1133 $  f(TS ts,PetscReal t,Vec U,Vec U_t,PetscReal a,Mat *A,Mat *B,MatStructure *flag,void *ctx);
1134 
1135 +  t    - time at step/stage being solved
1136 .  U    - state vector
1137 .  U_t  - time derivative of state vector
1138 .  a    - shift
1139 .  A    - Jacobian of F(t,U,W+a*U), equivalent to dF/dU + a*dF/dU_t
1140 .  B    - preconditioning matrix for A, may be same as A
1141 .  flag - flag indicating information about the preconditioner matrix
1142           structure (same as flag in KSPSetOperators())
1143 -  ctx  - [optional] user-defined context for matrix evaluation routine
1144 
1145    Notes:
1146    The matrices A and B are exactly the matrices that are used by SNES for the nonlinear solve.
1147 
1148    The matrix dF/dU + a*dF/dU_t you provide turns out to be
1149    the Jacobian of F(t,U,W+a*U) where F(t,U,U_t) = 0 is the DAE to be solved.
1150    The time integrator internally approximates U_t by W+a*U where the positive "shift"
1151    a and vector W depend on the integration method, step size, and past states. For example with
1152    the backward Euler method a = 1/dt and W = -a*U(previous timestep) so
1153    W + a*U = a*(U - U(previous timestep)) = (U - U(previous timestep))/dt
1154 
1155    Level: beginner
1156 
1157 .keywords: TS, timestep, DAE, Jacobian
1158 
1159 .seealso: TSSetIFunction(), TSSetRHSJacobian(), SNESDefaultComputeJacobianColor(), SNESDefaultComputeJacobian()
1160 
1161 @*/
1162 PetscErrorCode  TSSetIJacobian(TS ts,Mat A,Mat B,TSIJacobian f,void *ctx)
1163 {
1164   PetscErrorCode ierr;
1165   SNES           snes;
1166   DM             dm;
1167 
1168   PetscFunctionBegin;
1169   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1170   if (A) PetscValidHeaderSpecific(A,MAT_CLASSID,2);
1171   if (B) PetscValidHeaderSpecific(B,MAT_CLASSID,3);
1172   if (A) PetscCheckSameComm(ts,1,A,2);
1173   if (B) PetscCheckSameComm(ts,1,B,3);
1174 
1175   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1176   ierr = DMTSSetIJacobian(dm,f,ctx);CHKERRQ(ierr);
1177 
1178   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1179   ierr = SNESSetJacobian(snes,A,B,SNESTSFormJacobian,ts);CHKERRQ(ierr);
1180   PetscFunctionReturn(0);
1181 }
1182 
1183 #undef __FUNCT__
1184 #define __FUNCT__ "TSLoad"
1185 /*@C
1186   TSLoad - Loads a KSP that has been stored in binary  with KSPView().
1187 
1188   Collective on PetscViewer
1189 
1190   Input Parameters:
1191 + newdm - the newly loaded TS, this needs to have been created with TSCreate() or
1192            some related function before a call to TSLoad().
1193 - viewer - binary file viewer, obtained from PetscViewerBinaryOpen()
1194 
1195    Level: intermediate
1196 
1197   Notes:
1198    The type is determined by the data in the file, any type set into the TS before this call is ignored.
1199 
1200   Notes for advanced users:
1201   Most users should not need to know the details of the binary storage
1202   format, since TSLoad() and TSView() completely hide these details.
1203   But for anyone who's interested, the standard binary matrix storage
1204   format is
1205 .vb
1206      has not yet been determined
1207 .ve
1208 
1209 .seealso: PetscViewerBinaryOpen(), TSView(), MatLoad(), VecLoad()
1210 @*/
1211 PetscErrorCode  TSLoad(TS ts, PetscViewer viewer)
1212 {
1213   PetscErrorCode ierr;
1214   PetscBool      isbinary;
1215   PetscInt       classid;
1216   char           type[256];
1217   DMTS           sdm;
1218   DM             dm;
1219 
1220   PetscFunctionBegin;
1221   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1222   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2);
1223   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1224   if (!isbinary) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid viewer; open viewer with PetscViewerBinaryOpen()");
1225 
1226   ierr = PetscViewerBinaryRead(viewer,&classid,1,PETSC_INT);CHKERRQ(ierr);
1227   if (classid != TS_FILE_CLASSID) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_WRONG,"Not TS next in file");
1228   ierr = PetscViewerBinaryRead(viewer,type,256,PETSC_CHAR);CHKERRQ(ierr);
1229   ierr = TSSetType(ts, type);CHKERRQ(ierr);
1230   if (ts->ops->load) {
1231     ierr = (*ts->ops->load)(ts,viewer);CHKERRQ(ierr);
1232   }
1233   ierr = DMCreate(PetscObjectComm((PetscObject)ts),&dm);CHKERRQ(ierr);
1234   ierr = DMLoad(dm,viewer);CHKERRQ(ierr);
1235   ierr = TSSetDM(ts,dm);CHKERRQ(ierr);
1236   ierr = DMCreateGlobalVector(ts->dm,&ts->vec_sol);CHKERRQ(ierr);
1237   ierr = VecLoad(ts->vec_sol,viewer);CHKERRQ(ierr);
1238   ierr = DMGetDMTS(ts->dm,&sdm);CHKERRQ(ierr);
1239   ierr = DMTSLoad(sdm,viewer);CHKERRQ(ierr);
1240   PetscFunctionReturn(0);
1241 }
1242 
1243 #include <petscdraw.h>
1244 #undef __FUNCT__
1245 #define __FUNCT__ "TSView"
1246 /*@C
1247     TSView - Prints the TS data structure.
1248 
1249     Collective on TS
1250 
1251     Input Parameters:
1252 +   ts - the TS context obtained from TSCreate()
1253 -   viewer - visualization context
1254 
1255     Options Database Key:
1256 .   -ts_view - calls TSView() at end of TSStep()
1257 
1258     Notes:
1259     The available visualization contexts include
1260 +     PETSC_VIEWER_STDOUT_SELF - standard output (default)
1261 -     PETSC_VIEWER_STDOUT_WORLD - synchronized standard
1262          output where only the first processor opens
1263          the file.  All other processors send their
1264          data to the first processor to print.
1265 
1266     The user can open an alternative visualization context with
1267     PetscViewerASCIIOpen() - output to a specified file.
1268 
1269     Level: beginner
1270 
1271 .keywords: TS, timestep, view
1272 
1273 .seealso: PetscViewerASCIIOpen()
1274 @*/
1275 PetscErrorCode  TSView(TS ts,PetscViewer viewer)
1276 {
1277   PetscErrorCode ierr;
1278   TSType         type;
1279   PetscBool      iascii,isstring,isundials,isbinary,isdraw;
1280   DMTS           sdm;
1281 
1282   PetscFunctionBegin;
1283   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1284   if (!viewer) {
1285     ierr = PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)ts),&viewer);CHKERRQ(ierr);
1286   }
1287   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_CLASSID,2);
1288   PetscCheckSameComm(ts,1,viewer,2);
1289 
1290   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1291   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSTRING,&isstring);CHKERRQ(ierr);
1292   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1293   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1294   if (iascii) {
1295     ierr = PetscObjectPrintClassNamePrefixType((PetscObject)ts,viewer,"TS Object");CHKERRQ(ierr);
1296     ierr = PetscViewerASCIIPrintf(viewer,"  maximum steps=%D\n",ts->max_steps);CHKERRQ(ierr);
1297     ierr = PetscViewerASCIIPrintf(viewer,"  maximum time=%G\n",ts->max_time);CHKERRQ(ierr);
1298     if (ts->problem_type == TS_NONLINEAR) {
1299       ierr = PetscViewerASCIIPrintf(viewer,"  total number of nonlinear solver iterations=%D\n",ts->snes_its);CHKERRQ(ierr);
1300       ierr = PetscViewerASCIIPrintf(viewer,"  total number of nonlinear solve failures=%D\n",ts->num_snes_failures);CHKERRQ(ierr);
1301     }
1302     ierr = PetscViewerASCIIPrintf(viewer,"  total number of linear solver iterations=%D\n",ts->ksp_its);CHKERRQ(ierr);
1303     ierr = PetscViewerASCIIPrintf(viewer,"  total number of rejected steps=%D\n",ts->reject);CHKERRQ(ierr);
1304     ierr = DMGetDMTS(ts->dm,&sdm);CHKERRQ(ierr);
1305     ierr = DMTSView(sdm,viewer);CHKERRQ(ierr);
1306     if (ts->ops->view) {
1307       ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
1308       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
1309       ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
1310     }
1311   } else if (isstring) {
1312     ierr = TSGetType(ts,&type);CHKERRQ(ierr);
1313     ierr = PetscViewerStringSPrintf(viewer," %-7.7s",type);CHKERRQ(ierr);
1314   } else if (isbinary) {
1315     PetscInt    classid = TS_FILE_CLASSID;
1316     MPI_Comm    comm;
1317     PetscMPIInt rank;
1318     char        type[256];
1319 
1320     ierr = PetscObjectGetComm((PetscObject)ts,&comm);CHKERRQ(ierr);
1321     ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
1322     if (!rank) {
1323       ierr = PetscViewerBinaryWrite(viewer,&classid,1,PETSC_INT,PETSC_FALSE);CHKERRQ(ierr);
1324       ierr = PetscStrncpy(type,((PetscObject)ts)->type_name,256);CHKERRQ(ierr);
1325       ierr = PetscViewerBinaryWrite(viewer,type,256,PETSC_CHAR,PETSC_FALSE);CHKERRQ(ierr);
1326     }
1327     if (ts->ops->view) {
1328       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
1329     }
1330     ierr = DMView(ts->dm,viewer);CHKERRQ(ierr);
1331     ierr = VecView(ts->vec_sol,viewer);CHKERRQ(ierr);
1332     ierr = DMGetDMTS(ts->dm,&sdm);CHKERRQ(ierr);
1333     ierr = DMTSView(sdm,viewer);CHKERRQ(ierr);
1334   } else if (isdraw) {
1335     PetscDraw draw;
1336     char      str[36];
1337     PetscReal x,y,bottom,h;
1338 
1339     ierr   = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
1340     ierr   = PetscDrawGetCurrentPoint(draw,&x,&y);CHKERRQ(ierr);
1341     ierr   = PetscStrcpy(str,"TS: ");CHKERRQ(ierr);
1342     ierr   = PetscStrcat(str,((PetscObject)ts)->type_name);CHKERRQ(ierr);
1343     ierr   = PetscDrawBoxedString(draw,x,y,PETSC_DRAW_BLACK,PETSC_DRAW_BLACK,str,NULL,&h);CHKERRQ(ierr);
1344     bottom = y - h;
1345     ierr   = PetscDrawPushCurrentPoint(draw,x,bottom);CHKERRQ(ierr);
1346     if (ts->ops->view) {
1347       ierr = (*ts->ops->view)(ts,viewer);CHKERRQ(ierr);
1348     }
1349     ierr = PetscDrawPopCurrentPoint(draw);CHKERRQ(ierr);
1350   }
1351   ierr = PetscViewerASCIIPushTab(viewer);CHKERRQ(ierr);
1352   ierr = PetscObjectTypeCompare((PetscObject)ts,TSSUNDIALS,&isundials);CHKERRQ(ierr);
1353   ierr = PetscViewerASCIIPopTab(viewer);CHKERRQ(ierr);
1354   PetscFunctionReturn(0);
1355 }
1356 
1357 
1358 #undef __FUNCT__
1359 #define __FUNCT__ "TSSetApplicationContext"
1360 /*@
1361    TSSetApplicationContext - Sets an optional user-defined context for
1362    the timesteppers.
1363 
1364    Logically Collective on TS
1365 
1366    Input Parameters:
1367 +  ts - the TS context obtained from TSCreate()
1368 -  usrP - optional user context
1369 
1370    Level: intermediate
1371 
1372 .keywords: TS, timestep, set, application, context
1373 
1374 .seealso: TSGetApplicationContext()
1375 @*/
1376 PetscErrorCode  TSSetApplicationContext(TS ts,void *usrP)
1377 {
1378   PetscFunctionBegin;
1379   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1380   ts->user = usrP;
1381   PetscFunctionReturn(0);
1382 }
1383 
1384 #undef __FUNCT__
1385 #define __FUNCT__ "TSGetApplicationContext"
1386 /*@
1387     TSGetApplicationContext - Gets the user-defined context for the
1388     timestepper.
1389 
1390     Not Collective
1391 
1392     Input Parameter:
1393 .   ts - the TS context obtained from TSCreate()
1394 
1395     Output Parameter:
1396 .   usrP - user context
1397 
1398     Level: intermediate
1399 
1400 .keywords: TS, timestep, get, application, context
1401 
1402 .seealso: TSSetApplicationContext()
1403 @*/
1404 PetscErrorCode  TSGetApplicationContext(TS ts,void *usrP)
1405 {
1406   PetscFunctionBegin;
1407   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1408   *(void**)usrP = ts->user;
1409   PetscFunctionReturn(0);
1410 }
1411 
1412 #undef __FUNCT__
1413 #define __FUNCT__ "TSGetTimeStepNumber"
1414 /*@
1415    TSGetTimeStepNumber - Gets the number of time steps completed.
1416 
1417    Not Collective
1418 
1419    Input Parameter:
1420 .  ts - the TS context obtained from TSCreate()
1421 
1422    Output Parameter:
1423 .  iter - number of steps completed so far
1424 
1425    Level: intermediate
1426 
1427 .keywords: TS, timestep, get, iteration, number
1428 .seealso: TSGetTime(), TSGetTimeStep(), TSSetPreStep(), TSSetPreStage(), TSSetPostStep()
1429 @*/
1430 PetscErrorCode  TSGetTimeStepNumber(TS ts,PetscInt *iter)
1431 {
1432   PetscFunctionBegin;
1433   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1434   PetscValidIntPointer(iter,2);
1435   *iter = ts->steps;
1436   PetscFunctionReturn(0);
1437 }
1438 
1439 #undef __FUNCT__
1440 #define __FUNCT__ "TSSetInitialTimeStep"
1441 /*@
1442    TSSetInitialTimeStep - Sets the initial timestep to be used,
1443    as well as the initial time.
1444 
1445    Logically Collective on TS
1446 
1447    Input Parameters:
1448 +  ts - the TS context obtained from TSCreate()
1449 .  initial_time - the initial time
1450 -  time_step - the size of the timestep
1451 
1452    Level: intermediate
1453 
1454 .seealso: TSSetTimeStep(), TSGetTimeStep()
1455 
1456 .keywords: TS, set, initial, timestep
1457 @*/
1458 PetscErrorCode  TSSetInitialTimeStep(TS ts,PetscReal initial_time,PetscReal time_step)
1459 {
1460   PetscErrorCode ierr;
1461 
1462   PetscFunctionBegin;
1463   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1464   ierr = TSSetTimeStep(ts,time_step);CHKERRQ(ierr);
1465   ierr = TSSetTime(ts,initial_time);CHKERRQ(ierr);
1466   PetscFunctionReturn(0);
1467 }
1468 
1469 #undef __FUNCT__
1470 #define __FUNCT__ "TSSetTimeStep"
1471 /*@
1472    TSSetTimeStep - Allows one to reset the timestep at any time,
1473    useful for simple pseudo-timestepping codes.
1474 
1475    Logically Collective on TS
1476 
1477    Input Parameters:
1478 +  ts - the TS context obtained from TSCreate()
1479 -  time_step - the size of the timestep
1480 
1481    Level: intermediate
1482 
1483 .seealso: TSSetInitialTimeStep(), TSGetTimeStep()
1484 
1485 .keywords: TS, set, timestep
1486 @*/
1487 PetscErrorCode  TSSetTimeStep(TS ts,PetscReal time_step)
1488 {
1489   PetscFunctionBegin;
1490   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1491   PetscValidLogicalCollectiveReal(ts,time_step,2);
1492   ts->time_step      = time_step;
1493   ts->time_step_orig = time_step;
1494   PetscFunctionReturn(0);
1495 }
1496 
1497 #undef __FUNCT__
1498 #define __FUNCT__ "TSSetExactFinalTime"
1499 /*@
1500    TSSetExactFinalTime - Determines whether to adapt the final time step to
1501      match the exact final time, interpolate solution to the exact final time,
1502      or just return at the final time TS computed.
1503 
1504   Logically Collective on TS
1505 
1506    Input Parameter:
1507 +   ts - the time-step context
1508 -   eftopt - exact final time option
1509 
1510    Level: beginner
1511 
1512 .seealso: TSExactFinalTimeOption
1513 @*/
1514 PetscErrorCode  TSSetExactFinalTime(TS ts,TSExactFinalTimeOption eftopt)
1515 {
1516   PetscFunctionBegin;
1517   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1518   PetscValidLogicalCollectiveEnum(ts,eftopt,2);
1519   ts->exact_final_time = eftopt;
1520   PetscFunctionReturn(0);
1521 }
1522 
1523 #undef __FUNCT__
1524 #define __FUNCT__ "TSGetTimeStep"
1525 /*@
1526    TSGetTimeStep - Gets the current timestep size.
1527 
1528    Not Collective
1529 
1530    Input Parameter:
1531 .  ts - the TS context obtained from TSCreate()
1532 
1533    Output Parameter:
1534 .  dt - the current timestep size
1535 
1536    Level: intermediate
1537 
1538 .seealso: TSSetInitialTimeStep(), TSGetTimeStep()
1539 
1540 .keywords: TS, get, timestep
1541 @*/
1542 PetscErrorCode  TSGetTimeStep(TS ts,PetscReal *dt)
1543 {
1544   PetscFunctionBegin;
1545   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1546   PetscValidRealPointer(dt,2);
1547   *dt = ts->time_step;
1548   PetscFunctionReturn(0);
1549 }
1550 
1551 #undef __FUNCT__
1552 #define __FUNCT__ "TSGetSolution"
1553 /*@
1554    TSGetSolution - Returns the solution at the present timestep. It
1555    is valid to call this routine inside the function that you are evaluating
1556    in order to move to the new timestep. This vector not changed until
1557    the solution at the next timestep has been calculated.
1558 
1559    Not Collective, but Vec returned is parallel if TS is parallel
1560 
1561    Input Parameter:
1562 .  ts - the TS context obtained from TSCreate()
1563 
1564    Output Parameter:
1565 .  v - the vector containing the solution
1566 
1567    Level: intermediate
1568 
1569 .seealso: TSGetTimeStep()
1570 
1571 .keywords: TS, timestep, get, solution
1572 @*/
1573 PetscErrorCode  TSGetSolution(TS ts,Vec *v)
1574 {
1575   PetscFunctionBegin;
1576   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1577   PetscValidPointer(v,2);
1578   *v = ts->vec_sol;
1579   PetscFunctionReturn(0);
1580 }
1581 
1582 /* ----- Routines to initialize and destroy a timestepper ---- */
1583 #undef __FUNCT__
1584 #define __FUNCT__ "TSSetProblemType"
1585 /*@
1586   TSSetProblemType - Sets the type of problem to be solved.
1587 
1588   Not collective
1589 
1590   Input Parameters:
1591 + ts   - The TS
1592 - type - One of TS_LINEAR, TS_NONLINEAR where these types refer to problems of the forms
1593 .vb
1594          U_t - A U = 0      (linear)
1595          U_t - A(t) U = 0   (linear)
1596          F(t,U,U_t) = 0     (nonlinear)
1597 .ve
1598 
1599    Level: beginner
1600 
1601 .keywords: TS, problem type
1602 .seealso: TSSetUp(), TSProblemType, TS
1603 @*/
1604 PetscErrorCode  TSSetProblemType(TS ts, TSProblemType type)
1605 {
1606   PetscErrorCode ierr;
1607 
1608   PetscFunctionBegin;
1609   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
1610   ts->problem_type = type;
1611   if (type == TS_LINEAR) {
1612     SNES snes;
1613     ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1614     ierr = SNESSetType(snes,SNESKSPONLY);CHKERRQ(ierr);
1615   }
1616   PetscFunctionReturn(0);
1617 }
1618 
1619 #undef __FUNCT__
1620 #define __FUNCT__ "TSGetProblemType"
1621 /*@C
1622   TSGetProblemType - Gets the type of problem to be solved.
1623 
1624   Not collective
1625 
1626   Input Parameter:
1627 . ts   - The TS
1628 
1629   Output Parameter:
1630 . type - One of TS_LINEAR, TS_NONLINEAR where these types refer to problems of the forms
1631 .vb
1632          M U_t = A U
1633          M(t) U_t = A(t) U
1634          F(t,U,U_t)
1635 .ve
1636 
1637    Level: beginner
1638 
1639 .keywords: TS, problem type
1640 .seealso: TSSetUp(), TSProblemType, TS
1641 @*/
1642 PetscErrorCode  TSGetProblemType(TS ts, TSProblemType *type)
1643 {
1644   PetscFunctionBegin;
1645   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
1646   PetscValidIntPointer(type,2);
1647   *type = ts->problem_type;
1648   PetscFunctionReturn(0);
1649 }
1650 
1651 #undef __FUNCT__
1652 #define __FUNCT__ "TSSetUp"
1653 /*@
1654    TSSetUp - Sets up the internal data structures for the later use
1655    of a timestepper.
1656 
1657    Collective on TS
1658 
1659    Input Parameter:
1660 .  ts - the TS context obtained from TSCreate()
1661 
1662    Notes:
1663    For basic use of the TS solvers the user need not explicitly call
1664    TSSetUp(), since these actions will automatically occur during
1665    the call to TSStep().  However, if one wishes to control this
1666    phase separately, TSSetUp() should be called after TSCreate()
1667    and optional routines of the form TSSetXXX(), but before TSStep().
1668 
1669    Level: advanced
1670 
1671 .keywords: TS, timestep, setup
1672 
1673 .seealso: TSCreate(), TSStep(), TSDestroy()
1674 @*/
1675 PetscErrorCode  TSSetUp(TS ts)
1676 {
1677   PetscErrorCode ierr;
1678   DM             dm;
1679   PetscErrorCode (*func)(SNES,Vec,Vec,void*);
1680   PetscErrorCode (*jac)(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
1681   TSIJacobian    ijac;
1682   TSRHSJacobian  rhsjac;
1683 
1684   PetscFunctionBegin;
1685   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1686   if (ts->setupcalled) PetscFunctionReturn(0);
1687 
1688   if (!((PetscObject)ts)->type_name) {
1689     ierr = TSSetType(ts,TSEULER);CHKERRQ(ierr);
1690   }
1691 
1692   if (!ts->vec_sol) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call TSSetSolution() first");
1693 
1694   ierr = TSGetTSAdapt(ts,&ts->adapt);CHKERRQ(ierr);
1695 
1696   if (ts->ops->setup) {
1697     ierr = (*ts->ops->setup)(ts);CHKERRQ(ierr);
1698   }
1699 
1700   /* in the case where we've set a DMTSFunction or what have you, we need the default SNESFunction
1701    to be set right but can't do it elsewhere due to the overreliance on ctx=ts.
1702    */
1703   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
1704   ierr = DMSNESGetFunction(dm,&func,NULL);CHKERRQ(ierr);
1705   if (!func) {
1706     ierr =DMSNESSetFunction(dm,SNESTSFormFunction,ts);CHKERRQ(ierr);
1707   }
1708   /* if the SNES doesn't have a jacobian set and the TS has an ijacobian or rhsjacobian set, set the SNES to use it.
1709      Otherwise, the SNES will use coloring internally to form the Jacobian.
1710    */
1711   ierr = DMSNESGetJacobian(dm,&jac,NULL);CHKERRQ(ierr);
1712   ierr = DMTSGetIJacobian(dm,&ijac,NULL);CHKERRQ(ierr);
1713   ierr = DMTSGetRHSJacobian(dm,&rhsjac,NULL);CHKERRQ(ierr);
1714   if (!jac && (ijac || rhsjac)) {
1715     ierr = DMSNESSetJacobian(dm,SNESTSFormJacobian,ts);CHKERRQ(ierr);
1716   }
1717   ts->setupcalled = PETSC_TRUE;
1718   PetscFunctionReturn(0);
1719 }
1720 
1721 #undef __FUNCT__
1722 #define __FUNCT__ "TSReset"
1723 /*@
1724    TSReset - Resets a TS context and removes any allocated Vecs and Mats.
1725 
1726    Collective on TS
1727 
1728    Input Parameter:
1729 .  ts - the TS context obtained from TSCreate()
1730 
1731    Level: beginner
1732 
1733 .keywords: TS, timestep, reset
1734 
1735 .seealso: TSCreate(), TSSetup(), TSDestroy()
1736 @*/
1737 PetscErrorCode  TSReset(TS ts)
1738 {
1739   PetscErrorCode ierr;
1740 
1741   PetscFunctionBegin;
1742   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1743   if (ts->ops->reset) {
1744     ierr = (*ts->ops->reset)(ts);CHKERRQ(ierr);
1745   }
1746   if (ts->snes) {ierr = SNESReset(ts->snes);CHKERRQ(ierr);}
1747 
1748   ierr = MatDestroy(&ts->Arhs);CHKERRQ(ierr);
1749   ierr = MatDestroy(&ts->Brhs);CHKERRQ(ierr);
1750   ierr = VecDestroy(&ts->Frhs);CHKERRQ(ierr);
1751   ierr = VecDestroy(&ts->vec_sol);CHKERRQ(ierr);
1752   ierr = VecDestroy(&ts->vatol);CHKERRQ(ierr);
1753   ierr = VecDestroy(&ts->vrtol);CHKERRQ(ierr);
1754   ierr = VecDestroyVecs(ts->nwork,&ts->work);CHKERRQ(ierr);
1755 
1756   ts->setupcalled = PETSC_FALSE;
1757   PetscFunctionReturn(0);
1758 }
1759 
1760 #undef __FUNCT__
1761 #define __FUNCT__ "TSDestroy"
1762 /*@
1763    TSDestroy - Destroys the timestepper context that was created
1764    with TSCreate().
1765 
1766    Collective on TS
1767 
1768    Input Parameter:
1769 .  ts - the TS context obtained from TSCreate()
1770 
1771    Level: beginner
1772 
1773 .keywords: TS, timestepper, destroy
1774 
1775 .seealso: TSCreate(), TSSetUp(), TSSolve()
1776 @*/
1777 PetscErrorCode  TSDestroy(TS *ts)
1778 {
1779   PetscErrorCode ierr;
1780 
1781   PetscFunctionBegin;
1782   if (!*ts) PetscFunctionReturn(0);
1783   PetscValidHeaderSpecific((*ts),TS_CLASSID,1);
1784   if (--((PetscObject)(*ts))->refct > 0) {*ts = 0; PetscFunctionReturn(0);}
1785 
1786   ierr = TSReset((*ts));CHKERRQ(ierr);
1787 
1788   /* if memory was published with AMS then destroy it */
1789   ierr = PetscObjectDepublish((*ts));CHKERRQ(ierr);
1790   if ((*ts)->ops->destroy) {ierr = (*(*ts)->ops->destroy)((*ts));CHKERRQ(ierr);}
1791 
1792   ierr = TSAdaptDestroy(&(*ts)->adapt);CHKERRQ(ierr);
1793   ierr = SNESDestroy(&(*ts)->snes);CHKERRQ(ierr);
1794   ierr = DMDestroy(&(*ts)->dm);CHKERRQ(ierr);
1795   ierr = TSMonitorCancel((*ts));CHKERRQ(ierr);
1796 
1797   ierr = PetscHeaderDestroy(ts);CHKERRQ(ierr);
1798   PetscFunctionReturn(0);
1799 }
1800 
1801 #undef __FUNCT__
1802 #define __FUNCT__ "TSGetSNES"
1803 /*@
1804    TSGetSNES - Returns the SNES (nonlinear solver) associated with
1805    a TS (timestepper) context. Valid only for nonlinear problems.
1806 
1807    Not Collective, but SNES is parallel if TS is parallel
1808 
1809    Input Parameter:
1810 .  ts - the TS context obtained from TSCreate()
1811 
1812    Output Parameter:
1813 .  snes - the nonlinear solver context
1814 
1815    Notes:
1816    The user can then directly manipulate the SNES context to set various
1817    options, etc.  Likewise, the user can then extract and manipulate the
1818    KSP, KSP, and PC contexts as well.
1819 
1820    TSGetSNES() does not work for integrators that do not use SNES; in
1821    this case TSGetSNES() returns NULL in snes.
1822 
1823    Level: beginner
1824 
1825 .keywords: timestep, get, SNES
1826 @*/
1827 PetscErrorCode  TSGetSNES(TS ts,SNES *snes)
1828 {
1829   PetscErrorCode ierr;
1830 
1831   PetscFunctionBegin;
1832   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1833   PetscValidPointer(snes,2);
1834   if (!ts->snes) {
1835     ierr = SNESCreate(PetscObjectComm((PetscObject)ts),&ts->snes);CHKERRQ(ierr);
1836     ierr = SNESSetFunction(ts->snes,NULL,SNESTSFormFunction,ts);CHKERRQ(ierr);
1837     ierr = PetscLogObjectParent(ts,ts->snes);CHKERRQ(ierr);
1838     ierr = PetscObjectIncrementTabLevel((PetscObject)ts->snes,(PetscObject)ts,1);CHKERRQ(ierr);
1839     if (ts->dm) {ierr = SNESSetDM(ts->snes,ts->dm);CHKERRQ(ierr);}
1840     if (ts->problem_type == TS_LINEAR) {
1841       ierr = SNESSetType(ts->snes,SNESKSPONLY);CHKERRQ(ierr);
1842     }
1843   }
1844   *snes = ts->snes;
1845   PetscFunctionReturn(0);
1846 }
1847 
1848 #undef __FUNCT__
1849 #define __FUNCT__ "TSSetSNES"
1850 /*@
1851    TSSetSNES - Set the SNES (nonlinear solver) to be used by the timestepping context
1852 
1853    Collective
1854 
1855    Input Parameter:
1856 +  ts - the TS context obtained from TSCreate()
1857 -  snes - the nonlinear solver context
1858 
1859    Notes:
1860    Most users should have the TS created by calling TSGetSNES()
1861 
1862    Level: developer
1863 
1864 .keywords: timestep, set, SNES
1865 @*/
1866 PetscErrorCode TSSetSNES(TS ts,SNES snes)
1867 {
1868   PetscErrorCode ierr;
1869   PetscErrorCode (*func)(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
1870 
1871   PetscFunctionBegin;
1872   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1873   PetscValidHeaderSpecific(snes,SNES_CLASSID,2);
1874   ierr = PetscObjectReference((PetscObject)snes);CHKERRQ(ierr);
1875   ierr = SNESDestroy(&ts->snes);CHKERRQ(ierr);
1876 
1877   ts->snes = snes;
1878 
1879   ierr = SNESSetFunction(ts->snes,NULL,SNESTSFormFunction,ts);CHKERRQ(ierr);
1880   ierr = SNESGetJacobian(ts->snes,NULL,NULL,&func,NULL);CHKERRQ(ierr);
1881   if (func == SNESTSFormJacobian) {
1882     ierr = SNESSetJacobian(ts->snes,NULL,NULL,SNESTSFormJacobian,ts);CHKERRQ(ierr);
1883   }
1884   PetscFunctionReturn(0);
1885 }
1886 
1887 #undef __FUNCT__
1888 #define __FUNCT__ "TSGetKSP"
1889 /*@
1890    TSGetKSP - Returns the KSP (linear solver) associated with
1891    a TS (timestepper) context.
1892 
1893    Not Collective, but KSP is parallel if TS is parallel
1894 
1895    Input Parameter:
1896 .  ts - the TS context obtained from TSCreate()
1897 
1898    Output Parameter:
1899 .  ksp - the nonlinear solver context
1900 
1901    Notes:
1902    The user can then directly manipulate the KSP context to set various
1903    options, etc.  Likewise, the user can then extract and manipulate the
1904    KSP and PC contexts as well.
1905 
1906    TSGetKSP() does not work for integrators that do not use KSP;
1907    in this case TSGetKSP() returns NULL in ksp.
1908 
1909    Level: beginner
1910 
1911 .keywords: timestep, get, KSP
1912 @*/
1913 PetscErrorCode  TSGetKSP(TS ts,KSP *ksp)
1914 {
1915   PetscErrorCode ierr;
1916   SNES           snes;
1917 
1918   PetscFunctionBegin;
1919   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1920   PetscValidPointer(ksp,2);
1921   if (!((PetscObject)ts)->type_name) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"KSP is not created yet. Call TSSetType() first");
1922   if (ts->problem_type != TS_LINEAR) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Linear only; use TSGetSNES()");
1923   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
1924   ierr = SNESGetKSP(snes,ksp);CHKERRQ(ierr);
1925   PetscFunctionReturn(0);
1926 }
1927 
1928 /* ----------- Routines to set solver parameters ---------- */
1929 
1930 #undef __FUNCT__
1931 #define __FUNCT__ "TSGetDuration"
1932 /*@
1933    TSGetDuration - Gets the maximum number of timesteps to use and
1934    maximum time for iteration.
1935 
1936    Not Collective
1937 
1938    Input Parameters:
1939 +  ts       - the TS context obtained from TSCreate()
1940 .  maxsteps - maximum number of iterations to use, or NULL
1941 -  maxtime  - final time to iterate to, or NULL
1942 
1943    Level: intermediate
1944 
1945 .keywords: TS, timestep, get, maximum, iterations, time
1946 @*/
1947 PetscErrorCode  TSGetDuration(TS ts, PetscInt *maxsteps, PetscReal *maxtime)
1948 {
1949   PetscFunctionBegin;
1950   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
1951   if (maxsteps) {
1952     PetscValidIntPointer(maxsteps,2);
1953     *maxsteps = ts->max_steps;
1954   }
1955   if (maxtime) {
1956     PetscValidScalarPointer(maxtime,3);
1957     *maxtime = ts->max_time;
1958   }
1959   PetscFunctionReturn(0);
1960 }
1961 
1962 #undef __FUNCT__
1963 #define __FUNCT__ "TSSetDuration"
1964 /*@
1965    TSSetDuration - Sets the maximum number of timesteps to use and
1966    maximum time for iteration.
1967 
1968    Logically Collective on TS
1969 
1970    Input Parameters:
1971 +  ts - the TS context obtained from TSCreate()
1972 .  maxsteps - maximum number of iterations to use
1973 -  maxtime - final time to iterate to
1974 
1975    Options Database Keys:
1976 .  -ts_max_steps <maxsteps> - Sets maxsteps
1977 .  -ts_final_time <maxtime> - Sets maxtime
1978 
1979    Notes:
1980    The default maximum number of iterations is 5000. Default time is 5.0
1981 
1982    Level: intermediate
1983 
1984 .keywords: TS, timestep, set, maximum, iterations
1985 
1986 .seealso: TSSetExactFinalTime()
1987 @*/
1988 PetscErrorCode  TSSetDuration(TS ts,PetscInt maxsteps,PetscReal maxtime)
1989 {
1990   PetscFunctionBegin;
1991   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
1992   PetscValidLogicalCollectiveInt(ts,maxsteps,2);
1993   PetscValidLogicalCollectiveReal(ts,maxtime,2);
1994   if (maxsteps >= 0) ts->max_steps = maxsteps;
1995   if (maxtime != PETSC_DEFAULT) ts->max_time = maxtime;
1996   PetscFunctionReturn(0);
1997 }
1998 
1999 #undef __FUNCT__
2000 #define __FUNCT__ "TSSetSolution"
2001 /*@
2002    TSSetSolution - Sets the initial solution vector
2003    for use by the TS routines.
2004 
2005    Logically Collective on TS and Vec
2006 
2007    Input Parameters:
2008 +  ts - the TS context obtained from TSCreate()
2009 -  u - the solution vector
2010 
2011    Level: beginner
2012 
2013 .keywords: TS, timestep, set, solution, initial conditions
2014 @*/
2015 PetscErrorCode  TSSetSolution(TS ts,Vec u)
2016 {
2017   PetscErrorCode ierr;
2018   DM             dm;
2019 
2020   PetscFunctionBegin;
2021   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2022   PetscValidHeaderSpecific(u,VEC_CLASSID,2);
2023   ierr = PetscObjectReference((PetscObject)u);CHKERRQ(ierr);
2024   ierr = VecDestroy(&ts->vec_sol);CHKERRQ(ierr);
2025 
2026   ts->vec_sol = u;
2027 
2028   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
2029   ierr = DMShellSetGlobalVector(dm,u);CHKERRQ(ierr);
2030   PetscFunctionReturn(0);
2031 }
2032 
2033 #undef __FUNCT__
2034 #define __FUNCT__ "TSSetPreStep"
2035 /*@C
2036   TSSetPreStep - Sets the general-purpose function
2037   called once at the beginning of each time step.
2038 
2039   Logically Collective on TS
2040 
2041   Input Parameters:
2042 + ts   - The TS context obtained from TSCreate()
2043 - func - The function
2044 
2045   Calling sequence of func:
2046 . func (TS ts);
2047 
2048   Level: intermediate
2049 
2050   Note:
2051   If a step is rejected, TSStep() will call this routine again before each attempt.
2052   The last completed time step number can be queried using TSGetTimeStepNumber(), the
2053   size of the step being attempted can be obtained using TSGetTimeStep().
2054 
2055 .keywords: TS, timestep
2056 .seealso: TSSetPreStage(), TSSetPostStep(), TSStep()
2057 @*/
2058 PetscErrorCode  TSSetPreStep(TS ts, PetscErrorCode (*func)(TS))
2059 {
2060   PetscFunctionBegin;
2061   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2062   ts->ops->prestep = func;
2063   PetscFunctionReturn(0);
2064 }
2065 
2066 #undef __FUNCT__
2067 #define __FUNCT__ "TSPreStep"
2068 /*@
2069   TSPreStep - Runs the user-defined pre-step function.
2070 
2071   Collective on TS
2072 
2073   Input Parameters:
2074 . ts   - The TS context obtained from TSCreate()
2075 
2076   Notes:
2077   TSPreStep() is typically used within time stepping implementations,
2078   so most users would not generally call this routine themselves.
2079 
2080   Level: developer
2081 
2082 .keywords: TS, timestep
2083 .seealso: TSSetPreStep(), TSPreStage(), TSPostStep()
2084 @*/
2085 PetscErrorCode  TSPreStep(TS ts)
2086 {
2087   PetscErrorCode ierr;
2088 
2089   PetscFunctionBegin;
2090   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2091   if (ts->ops->prestep) {
2092     PetscStackPush("TS PreStep function");
2093     ierr = (*ts->ops->prestep)(ts);CHKERRQ(ierr);
2094     PetscStackPop;
2095   }
2096   PetscFunctionReturn(0);
2097 }
2098 
2099 #undef __FUNCT__
2100 #define __FUNCT__ "TSSetPreStage"
2101 /*@C
2102   TSSetPreStage - Sets the general-purpose function
2103   called once at the beginning of each stage.
2104 
2105   Logically Collective on TS
2106 
2107   Input Parameters:
2108 + ts   - The TS context obtained from TSCreate()
2109 - func - The function
2110 
2111   Calling sequence of func:
2112 . PetscErrorCode func(TS ts, PetscReal stagetime);
2113 
2114   Level: intermediate
2115 
2116   Note:
2117   There may be several stages per time step. If the solve for a given stage fails, the step may be rejected and retried.
2118   The time step number being computed can be queried using TSGetTimeStepNumber() and the total size of the step being
2119   attempted can be obtained using TSGetTimeStep(). The time at the start of the step is available via TSGetTime().
2120 
2121 .keywords: TS, timestep
2122 .seealso: TSSetPreStep(), TSSetPostStep(), TSGetApplicationContext()
2123 @*/
2124 PetscErrorCode  TSSetPreStage(TS ts, PetscErrorCode (*func)(TS,PetscReal))
2125 {
2126   PetscFunctionBegin;
2127   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2128   ts->ops->prestage = func;
2129   PetscFunctionReturn(0);
2130 }
2131 
2132 #undef __FUNCT__
2133 #define __FUNCT__ "TSPreStage"
2134 /*@
2135   TSPreStage - Runs the user-defined pre-stage function set using TSSetPreStage()
2136 
2137   Collective on TS
2138 
2139   Input Parameters:
2140 . ts   - The TS context obtained from TSCreate()
2141 
2142   Notes:
2143   TSPreStage() is typically used within time stepping implementations,
2144   most users would not generally call this routine themselves.
2145 
2146   Level: developer
2147 
2148 .keywords: TS, timestep
2149 .seealso: TSSetPreStep(), TSPreStep(), TSPostStep()
2150 @*/
2151 PetscErrorCode  TSPreStage(TS ts, PetscReal stagetime)
2152 {
2153   PetscErrorCode ierr;
2154 
2155   PetscFunctionBegin;
2156   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2157   if (ts->ops->prestage) {
2158     PetscStackPush("TS PreStage function");
2159     ierr = (*ts->ops->prestage)(ts,stagetime);CHKERRQ(ierr);
2160     PetscStackPop;
2161   }
2162   PetscFunctionReturn(0);
2163 }
2164 
2165 #undef __FUNCT__
2166 #define __FUNCT__ "TSSetPostStep"
2167 /*@C
2168   TSSetPostStep - Sets the general-purpose function
2169   called once at the end of each time step.
2170 
2171   Logically Collective on TS
2172 
2173   Input Parameters:
2174 + ts   - The TS context obtained from TSCreate()
2175 - func - The function
2176 
2177   Calling sequence of func:
2178 $ func (TS ts);
2179 
2180   Level: intermediate
2181 
2182 .keywords: TS, timestep
2183 .seealso: TSSetPreStep(), TSSetPreStage(), TSGetTimeStep(), TSGetTimeStepNumber(), TSGetTime()
2184 @*/
2185 PetscErrorCode  TSSetPostStep(TS ts, PetscErrorCode (*func)(TS))
2186 {
2187   PetscFunctionBegin;
2188   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2189   ts->ops->poststep = func;
2190   PetscFunctionReturn(0);
2191 }
2192 
2193 #undef __FUNCT__
2194 #define __FUNCT__ "TSPostStep"
2195 /*@
2196   TSPostStep - Runs the user-defined post-step function.
2197 
2198   Collective on TS
2199 
2200   Input Parameters:
2201 . ts   - The TS context obtained from TSCreate()
2202 
2203   Notes:
2204   TSPostStep() is typically used within time stepping implementations,
2205   so most users would not generally call this routine themselves.
2206 
2207   Level: developer
2208 
2209 .keywords: TS, timestep
2210 @*/
2211 PetscErrorCode  TSPostStep(TS ts)
2212 {
2213   PetscErrorCode ierr;
2214 
2215   PetscFunctionBegin;
2216   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2217   if (ts->ops->poststep) {
2218     PetscStackPush("TS PostStep function");
2219     ierr = (*ts->ops->poststep)(ts);CHKERRQ(ierr);
2220     PetscStackPop;
2221   }
2222   PetscFunctionReturn(0);
2223 }
2224 
2225 /* ------------ Routines to set performance monitoring options ----------- */
2226 
2227 #undef __FUNCT__
2228 #define __FUNCT__ "TSMonitorSet"
2229 /*@C
2230    TSMonitorSet - Sets an ADDITIONAL function that is to be used at every
2231    timestep to display the iteration's  progress.
2232 
2233    Logically Collective on TS
2234 
2235    Input Parameters:
2236 +  ts - the TS context obtained from TSCreate()
2237 .  monitor - monitoring routine
2238 .  mctx - [optional] user-defined context for private data for the
2239              monitor routine (use NULL if no context is desired)
2240 -  monitordestroy - [optional] routine that frees monitor context
2241           (may be NULL)
2242 
2243    Calling sequence of monitor:
2244 $    int monitor(TS ts,PetscInt steps,PetscReal time,Vec u,void *mctx)
2245 
2246 +    ts - the TS context
2247 .    steps - iteration number (after the final time step the monitor routine is called with a step of -1, this is at the final time which may have
2248                                been interpolated to)
2249 .    time - current time
2250 .    u - current iterate
2251 -    mctx - [optional] monitoring context
2252 
2253    Notes:
2254    This routine adds an additional monitor to the list of monitors that
2255    already has been loaded.
2256 
2257    Fortran notes: Only a single monitor function can be set for each TS object
2258 
2259    Level: intermediate
2260 
2261 .keywords: TS, timestep, set, monitor
2262 
2263 .seealso: TSMonitorDefault(), TSMonitorCancel()
2264 @*/
2265 PetscErrorCode  TSMonitorSet(TS ts,PetscErrorCode (*monitor)(TS,PetscInt,PetscReal,Vec,void*),void *mctx,PetscErrorCode (*mdestroy)(void**))
2266 {
2267   PetscFunctionBegin;
2268   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2269   if (ts->numbermonitors >= MAXTSMONITORS) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Too many monitors set");
2270   ts->monitor[ts->numbermonitors]          = monitor;
2271   ts->monitordestroy[ts->numbermonitors]   = mdestroy;
2272   ts->monitorcontext[ts->numbermonitors++] = (void*)mctx;
2273   PetscFunctionReturn(0);
2274 }
2275 
2276 #undef __FUNCT__
2277 #define __FUNCT__ "TSMonitorCancel"
2278 /*@C
2279    TSMonitorCancel - Clears all the monitors that have been set on a time-step object.
2280 
2281    Logically Collective on TS
2282 
2283    Input Parameters:
2284 .  ts - the TS context obtained from TSCreate()
2285 
2286    Notes:
2287    There is no way to remove a single, specific monitor.
2288 
2289    Level: intermediate
2290 
2291 .keywords: TS, timestep, set, monitor
2292 
2293 .seealso: TSMonitorDefault(), TSMonitorSet()
2294 @*/
2295 PetscErrorCode  TSMonitorCancel(TS ts)
2296 {
2297   PetscErrorCode ierr;
2298   PetscInt       i;
2299 
2300   PetscFunctionBegin;
2301   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2302   for (i=0; i<ts->numbermonitors; i++) {
2303     if (ts->monitordestroy[i]) {
2304       ierr = (*ts->monitordestroy[i])(&ts->monitorcontext[i]);CHKERRQ(ierr);
2305     }
2306   }
2307   ts->numbermonitors = 0;
2308   PetscFunctionReturn(0);
2309 }
2310 
2311 #undef __FUNCT__
2312 #define __FUNCT__ "TSMonitorDefault"
2313 /*@
2314    TSMonitorDefault - Sets the Default monitor
2315 
2316    Level: intermediate
2317 
2318 .keywords: TS, set, monitor
2319 
2320 .seealso: TSMonitorDefault(), TSMonitorSet()
2321 @*/
2322 PetscErrorCode TSMonitorDefault(TS ts,PetscInt step,PetscReal ptime,Vec v,void *dummy)
2323 {
2324   PetscErrorCode ierr;
2325   PetscViewer    viewer = dummy ? (PetscViewer) dummy : PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)ts));
2326 
2327   PetscFunctionBegin;
2328   ierr = PetscViewerASCIIAddTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
2329   ierr = PetscViewerASCIIPrintf(viewer,"%D TS dt %g time %g\n",step,(double)ts->time_step,(double)ptime);CHKERRQ(ierr);
2330   ierr = PetscViewerASCIISubtractTab(viewer,((PetscObject)ts)->tablevel);CHKERRQ(ierr);
2331   PetscFunctionReturn(0);
2332 }
2333 
2334 #undef __FUNCT__
2335 #define __FUNCT__ "TSSetRetainStages"
2336 /*@
2337    TSSetRetainStages - Request that all stages in the upcoming step be stored so that interpolation will be available.
2338 
2339    Logically Collective on TS
2340 
2341    Input Argument:
2342 .  ts - time stepping context
2343 
2344    Output Argument:
2345 .  flg - PETSC_TRUE or PETSC_FALSE
2346 
2347    Level: intermediate
2348 
2349 .keywords: TS, set
2350 
2351 .seealso: TSInterpolate(), TSSetPostStep()
2352 @*/
2353 PetscErrorCode TSSetRetainStages(TS ts,PetscBool flg)
2354 {
2355   PetscFunctionBegin;
2356   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2357   ts->retain_stages = flg;
2358   PetscFunctionReturn(0);
2359 }
2360 
2361 #undef __FUNCT__
2362 #define __FUNCT__ "TSInterpolate"
2363 /*@
2364    TSInterpolate - Interpolate the solution computed during the previous step to an arbitrary location in the interval
2365 
2366    Collective on TS
2367 
2368    Input Argument:
2369 +  ts - time stepping context
2370 -  t - time to interpolate to
2371 
2372    Output Argument:
2373 .  U - state at given time
2374 
2375    Notes:
2376    The user should call TSSetRetainStages() before taking a step in which interpolation will be requested.
2377 
2378    Level: intermediate
2379 
2380    Developer Notes:
2381    TSInterpolate() and the storing of previous steps/stages should be generalized to support delay differential equations and continuous adjoints.
2382 
2383 .keywords: TS, set
2384 
2385 .seealso: TSSetRetainStages(), TSSetPostStep()
2386 @*/
2387 PetscErrorCode TSInterpolate(TS ts,PetscReal t,Vec U)
2388 {
2389   PetscErrorCode ierr;
2390 
2391   PetscFunctionBegin;
2392   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2393   if (t < ts->ptime - ts->time_step_prev || t > ts->ptime) SETERRQ3(PetscObjectComm((PetscObject)ts),PETSC_ERR_ARG_OUTOFRANGE,"Requested time %G not in last time steps [%G,%G]",t,ts->ptime-ts->time_step_prev,ts->ptime);
2394   if (!ts->ops->interpolate) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"%s does not provide interpolation",((PetscObject)ts)->type_name);
2395   ierr = (*ts->ops->interpolate)(ts,t,U);CHKERRQ(ierr);
2396   PetscFunctionReturn(0);
2397 }
2398 
2399 #undef __FUNCT__
2400 #define __FUNCT__ "TSStep"
2401 /*@
2402    TSStep - Steps one time step
2403 
2404    Collective on TS
2405 
2406    Input Parameter:
2407 .  ts - the TS context obtained from TSCreate()
2408 
2409    Level: intermediate
2410 
2411    Notes:
2412    The hook set using TSSetPreStep() is called before each attempt to take the step. In general, the time step size may
2413    be changed due to adaptive error controller or solve failures. Note that steps may contain multiple stages.
2414 
2415    This may over-step the final time provided in TSSetDuration() depending on the time-step used. TSSolve() interpolates to exactly the
2416    time provided in TSSetDuration(). One can use TSInterpolate() to determine an interpolated solution within the final timestep.
2417 
2418 .keywords: TS, timestep, solve
2419 
2420 .seealso: TSCreate(), TSSetUp(), TSDestroy(), TSSolve(), TSSetPreStep(), TSSetPreStage(), TSInterpolate()
2421 @*/
2422 PetscErrorCode  TSStep(TS ts)
2423 {
2424   PetscReal      ptime_prev;
2425   PetscErrorCode ierr;
2426 
2427   PetscFunctionBegin;
2428   PetscValidHeaderSpecific(ts, TS_CLASSID,1);
2429   ierr = TSSetUp(ts);CHKERRQ(ierr);
2430 
2431   ts->reason = TS_CONVERGED_ITERATING;
2432   ptime_prev = ts->ptime;
2433 
2434   ierr = PetscLogEventBegin(TS_Step,ts,0,0,0);CHKERRQ(ierr);
2435   ierr = (*ts->ops->step)(ts);CHKERRQ(ierr);
2436   ierr = PetscLogEventEnd(TS_Step,ts,0,0,0);CHKERRQ(ierr);
2437 
2438   ts->time_step_prev = ts->ptime - ptime_prev;
2439 
2440   if (ts->reason < 0) {
2441     if (ts->errorifstepfailed) {
2442       if (ts->reason == TS_DIVERGED_NONLINEAR_SOLVE) {
2443         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]);
2444       } else SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_NOT_CONVERGED,"TSStep has failed due to %s",TSConvergedReasons[ts->reason]);
2445     }
2446   } else if (!ts->reason) {
2447     if (ts->steps >= ts->max_steps)     ts->reason = TS_CONVERGED_ITS;
2448     else if (ts->ptime >= ts->max_time) ts->reason = TS_CONVERGED_TIME;
2449   }
2450   PetscFunctionReturn(0);
2451 }
2452 
2453 #undef __FUNCT__
2454 #define __FUNCT__ "TSEvaluateStep"
2455 /*@
2456    TSEvaluateStep - Evaluate the solution at the end of a time step with a given order of accuracy.
2457 
2458    Collective on TS
2459 
2460    Input Arguments:
2461 +  ts - time stepping context
2462 .  order - desired order of accuracy
2463 -  done - whether the step was evaluated at this order (pass NULL to generate an error if not available)
2464 
2465    Output Arguments:
2466 .  U - state at the end of the current step
2467 
2468    Level: advanced
2469 
2470    Notes:
2471    This function cannot be called until all stages have been evaluated.
2472    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.
2473 
2474 .seealso: TSStep(), TSAdapt
2475 @*/
2476 PetscErrorCode TSEvaluateStep(TS ts,PetscInt order,Vec U,PetscBool *done)
2477 {
2478   PetscErrorCode ierr;
2479 
2480   PetscFunctionBegin;
2481   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2482   PetscValidType(ts,1);
2483   PetscValidHeaderSpecific(U,VEC_CLASSID,3);
2484   if (!ts->ops->evaluatestep) SETERRQ1(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"TSEvaluateStep not implemented for type '%s'",((PetscObject)ts)->type_name);
2485   ierr = (*ts->ops->evaluatestep)(ts,order,U,done);CHKERRQ(ierr);
2486   PetscFunctionReturn(0);
2487 }
2488 
2489 #undef __FUNCT__
2490 #define __FUNCT__ "TSSolve"
2491 /*@
2492    TSSolve - Steps the requested number of timesteps.
2493 
2494    Collective on TS
2495 
2496    Input Parameter:
2497 +  ts - the TS context obtained from TSCreate()
2498 -  u - the solution vector  (can be null if TSSetSolution() was used, otherwise must contain the initial conditions)
2499 
2500    Level: beginner
2501 
2502    Notes:
2503    The final time returned by this function may be different from the time of the internally
2504    held state accessible by TSGetSolution() and TSGetTime() because the method may have
2505    stepped over the final time.
2506 
2507 .keywords: TS, timestep, solve
2508 
2509 .seealso: TSCreate(), TSSetSolution(), TSStep()
2510 @*/
2511 PetscErrorCode TSSolve(TS ts,Vec u)
2512 {
2513   PetscBool         flg;
2514   PetscViewer       viewer;
2515   PetscErrorCode    ierr;
2516   PetscViewerFormat format;
2517 
2518   PetscFunctionBegin;
2519   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2520   if (u) PetscValidHeaderSpecific(u,VEC_CLASSID,2);
2521   if (ts->exact_final_time == TS_EXACTFINALTIME_INTERPOLATE) {   /* Need ts->vec_sol to be distinct so it is not overwritten when we interpolate at the end */
2522     if (!ts->vec_sol || u == ts->vec_sol) {
2523       Vec y;
2524       ierr = VecDuplicate(u,&y);CHKERRQ(ierr);
2525       ierr = TSSetSolution(ts,y);CHKERRQ(ierr);
2526       ierr = VecDestroy(&y);CHKERRQ(ierr); /* grant ownership */
2527     }
2528     if (u) {
2529       ierr = VecCopy(u,ts->vec_sol);CHKERRQ(ierr);
2530     }
2531   } else if (u) {
2532     ierr = TSSetSolution(ts,u);CHKERRQ(ierr);
2533   }
2534   ierr = TSSetUp(ts);CHKERRQ(ierr);
2535   /* reset time step and iteration counters */
2536   ts->steps             = 0;
2537   ts->ksp_its           = 0;
2538   ts->snes_its          = 0;
2539   ts->num_snes_failures = 0;
2540   ts->reject            = 0;
2541   ts->reason            = TS_CONVERGED_ITERATING;
2542 
2543   if (ts->ops->solve) {         /* This private interface is transitional and should be removed when all implementations are updated. */
2544     ierr = (*ts->ops->solve)(ts);CHKERRQ(ierr);
2545     ierr = VecCopy(ts->vec_sol,u);CHKERRQ(ierr);
2546 
2547     ts->solvetime = ts->ptime;
2548   } else {
2549     /* steps the requested number of timesteps. */
2550     ierr = TSMonitor(ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
2551     if (ts->steps >= ts->max_steps)     ts->reason = TS_CONVERGED_ITS;
2552     else if (ts->ptime >= ts->max_time) ts->reason = TS_CONVERGED_TIME;
2553     while (!ts->reason) {
2554       ierr = TSStep(ts);CHKERRQ(ierr);
2555       ierr = TSPostStep(ts);CHKERRQ(ierr);
2556       ierr = TSMonitor(ts,ts->steps,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
2557     }
2558     if (ts->exact_final_time == TS_EXACTFINALTIME_INTERPOLATE && ts->ptime > ts->max_time) {
2559       ierr = TSInterpolate(ts,ts->max_time,u);CHKERRQ(ierr);
2560 
2561       ts->solvetime = ts->max_time;
2562     } else {
2563       if (u) {ierr = VecCopy(ts->vec_sol,u);CHKERRQ(ierr);}
2564       ts->solvetime = ts->ptime;
2565     }
2566   }
2567   ierr = TSMonitor(ts,-1,ts->ptime,ts->vec_sol);CHKERRQ(ierr);
2568   ierr = PetscOptionsGetViewer(PetscObjectComm((PetscObject)ts),((PetscObject)ts)->prefix,"-ts_view",&viewer,&format,&flg);CHKERRQ(ierr);
2569   if (flg && !PetscPreLoadingOn) {
2570     ierr = PetscViewerPushFormat(viewer,format);CHKERRQ(ierr);
2571     ierr = TSView(ts,viewer);CHKERRQ(ierr);
2572     ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr);
2573     ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
2574   }
2575   PetscFunctionReturn(0);
2576 }
2577 
2578 #undef __FUNCT__
2579 #define __FUNCT__ "TSMonitor"
2580 /*@
2581    TSMonitor - Runs all user-provided monitor routines set using TSMonitorSet()
2582 
2583    Collective on TS
2584 
2585    Input Parameters:
2586 +  ts - time stepping context obtained from TSCreate()
2587 .  step - step number that has just completed
2588 .  ptime - model time of the state
2589 -  u - state at the current model time
2590 
2591    Notes:
2592    TSMonitor() is typically used within the time stepping implementations.
2593    Users might call this function when using the TSStep() interface instead of TSSolve().
2594 
2595    Level: advanced
2596 
2597 .keywords: TS, timestep
2598 @*/
2599 PetscErrorCode TSMonitor(TS ts,PetscInt step,PetscReal ptime,Vec u)
2600 {
2601   PetscErrorCode ierr;
2602   PetscInt       i,n = ts->numbermonitors;
2603 
2604   PetscFunctionBegin;
2605   for (i=0; i<n; i++) {
2606     ierr = (*ts->monitor[i])(ts,step,ptime,u,ts->monitorcontext[i]);CHKERRQ(ierr);
2607   }
2608   PetscFunctionReturn(0);
2609 }
2610 
2611 /* ------------------------------------------------------------------------*/
2612 struct _n_TSMonitorLGCtx {
2613   PetscDrawLG lg;
2614   PetscInt    howoften;  /* when > 0 uses step % howoften, when negative only final solution plotted */
2615   PetscInt    ksp_its,snes_its;
2616 };
2617 
2618 
2619 #undef __FUNCT__
2620 #define __FUNCT__ "TSMonitorLGCtxCreate"
2621 /*@C
2622    TSMonitorLGCtxCreate - Creates a line graph context for use with
2623    TS to monitor the solution process graphically in various ways
2624 
2625    Collective on TS
2626 
2627    Input Parameters:
2628 +  host - the X display to open, or null for the local machine
2629 .  label - the title to put in the title bar
2630 .  x, y - the screen coordinates of the upper left coordinate of the window
2631 .  m, n - the screen width and height in pixels
2632 -  howoften - if positive then determines the frequency of the plotting, if -1 then only at the final time
2633 
2634    Output Parameter:
2635 .  ctx - the context
2636 
2637    Options Database Key:
2638 +  -ts_monitor_lg_timestep - automatically sets line graph monitor
2639 .  -ts_monitor_lg_solution -
2640 .  -ts_monitor_lg_error -
2641 .  -ts_monitor_lg_ksp_iterations -
2642 .  -ts_monitor_lg_snes_iterations -
2643 -  -lg_indicate_data_points <true,false> - indicate the data points (at each time step) on the plot; default is true
2644 
2645    Notes:
2646    Use TSMonitorLGCtxDestroy() to destroy.
2647 
2648    Level: intermediate
2649 
2650 .keywords: TS, monitor, line graph, residual, seealso
2651 
2652 .seealso: TSMonitorLGTimeStep(), TSMonitorSet(), TSMonitorLGSolution(), TSMonitorLGError()
2653 
2654 @*/
2655 PetscErrorCode  TSMonitorLGCtxCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscInt howoften,TSMonitorLGCtx *ctx)
2656 {
2657   PetscDraw      win;
2658   PetscErrorCode ierr;
2659   PetscBool      flg = PETSC_TRUE;
2660 
2661   PetscFunctionBegin;
2662   ierr = PetscNew(struct _n_TSMonitorLGCtx,ctx);CHKERRQ(ierr);
2663   ierr = PetscDrawCreate(comm,host,label,x,y,m,n,&win);CHKERRQ(ierr);
2664   ierr = PetscDrawSetFromOptions(win);CHKERRQ(ierr);
2665   ierr = PetscDrawLGCreate(win,1,&(*ctx)->lg);CHKERRQ(ierr);
2666   ierr = PetscOptionsGetBool(NULL,"-lg_indicate_data_points",&flg,NULL);CHKERRQ(ierr);
2667   if (flg) {
2668     ierr = PetscDrawLGIndicateDataPoints((*ctx)->lg);CHKERRQ(ierr);
2669   }
2670   ierr = PetscLogObjectParent((*ctx)->lg,win);CHKERRQ(ierr);
2671   (*ctx)->howoften = howoften;
2672   PetscFunctionReturn(0);
2673 }
2674 
2675 #undef __FUNCT__
2676 #define __FUNCT__ "TSMonitorLGTimeStep"
2677 PetscErrorCode TSMonitorLGTimeStep(TS ts,PetscInt n,PetscReal ptime,Vec v,void *monctx)
2678 {
2679   TSMonitorLGCtx ctx = (TSMonitorLGCtx) monctx;
2680   PetscReal      x   = ptime,y;
2681   PetscErrorCode ierr;
2682 
2683   PetscFunctionBegin;
2684   if (!n) {
2685     PetscDrawAxis axis;
2686     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
2687     ierr = PetscDrawAxisSetLabels(axis,"Timestep as function of time","Time","Time step");CHKERRQ(ierr);
2688     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
2689   }
2690   ierr = TSGetTimeStep(ts,&y);CHKERRQ(ierr);
2691   ierr = PetscDrawLGAddPoint(ctx->lg,&x,&y);CHKERRQ(ierr);
2692   if (((ctx->howoften > 0) && (!(n % ctx->howoften))) || ((ctx->howoften == -1) && (n == -1))) {
2693     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
2694   }
2695   PetscFunctionReturn(0);
2696 }
2697 
2698 #undef __FUNCT__
2699 #define __FUNCT__ "TSMonitorLGCtxDestroy"
2700 /*@C
2701    TSMonitorLGCtxDestroy - Destroys a line graph context that was created
2702    with TSMonitorLGCtxCreate().
2703 
2704    Collective on TSMonitorLGCtx
2705 
2706    Input Parameter:
2707 .  ctx - the monitor context
2708 
2709    Level: intermediate
2710 
2711 .keywords: TS, monitor, line graph, destroy
2712 
2713 .seealso: TSMonitorLGCtxCreate(),  TSMonitorSet(), TSMonitorLGTimeStep();
2714 @*/
2715 PetscErrorCode  TSMonitorLGCtxDestroy(TSMonitorLGCtx *ctx)
2716 {
2717   PetscDraw      draw;
2718   PetscErrorCode ierr;
2719 
2720   PetscFunctionBegin;
2721   ierr = PetscDrawLGGetDraw((*ctx)->lg,&draw);CHKERRQ(ierr);
2722   ierr = PetscDrawDestroy(&draw);CHKERRQ(ierr);
2723   ierr = PetscDrawLGDestroy(&(*ctx)->lg);CHKERRQ(ierr);
2724   ierr = PetscFree(*ctx);CHKERRQ(ierr);
2725   PetscFunctionReturn(0);
2726 }
2727 
2728 #undef __FUNCT__
2729 #define __FUNCT__ "TSGetTime"
2730 /*@
2731    TSGetTime - Gets the time of the most recently completed step.
2732 
2733    Not Collective
2734 
2735    Input Parameter:
2736 .  ts - the TS context obtained from TSCreate()
2737 
2738    Output Parameter:
2739 .  t  - the current time
2740 
2741    Level: beginner
2742 
2743    Note:
2744    When called during time step evaluation (e.g. during residual evaluation or via hooks set using TSSetPreStep(),
2745    TSSetPreStage(), or TSSetPostStep()), the time is the time at the start of the step being evaluated.
2746 
2747 .seealso: TSSetInitialTimeStep(), TSGetTimeStep()
2748 
2749 .keywords: TS, get, time
2750 @*/
2751 PetscErrorCode  TSGetTime(TS ts,PetscReal *t)
2752 {
2753   PetscFunctionBegin;
2754   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2755   PetscValidRealPointer(t,2);
2756   *t = ts->ptime;
2757   PetscFunctionReturn(0);
2758 }
2759 
2760 #undef __FUNCT__
2761 #define __FUNCT__ "TSSetTime"
2762 /*@
2763    TSSetTime - Allows one to reset the time.
2764 
2765    Logically Collective on TS
2766 
2767    Input Parameters:
2768 +  ts - the TS context obtained from TSCreate()
2769 -  time - the time
2770 
2771    Level: intermediate
2772 
2773 .seealso: TSGetTime(), TSSetDuration()
2774 
2775 .keywords: TS, set, time
2776 @*/
2777 PetscErrorCode  TSSetTime(TS ts, PetscReal t)
2778 {
2779   PetscFunctionBegin;
2780   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2781   PetscValidLogicalCollectiveReal(ts,t,2);
2782   ts->ptime = t;
2783   PetscFunctionReturn(0);
2784 }
2785 
2786 #undef __FUNCT__
2787 #define __FUNCT__ "TSSetOptionsPrefix"
2788 /*@C
2789    TSSetOptionsPrefix - Sets the prefix used for searching for all
2790    TS options in the database.
2791 
2792    Logically Collective on TS
2793 
2794    Input Parameter:
2795 +  ts     - The TS context
2796 -  prefix - The prefix to prepend to all option names
2797 
2798    Notes:
2799    A hyphen (-) must NOT be given at the beginning of the prefix name.
2800    The first character of all runtime options is AUTOMATICALLY the
2801    hyphen.
2802 
2803    Level: advanced
2804 
2805 .keywords: TS, set, options, prefix, database
2806 
2807 .seealso: TSSetFromOptions()
2808 
2809 @*/
2810 PetscErrorCode  TSSetOptionsPrefix(TS ts,const char prefix[])
2811 {
2812   PetscErrorCode ierr;
2813   SNES           snes;
2814 
2815   PetscFunctionBegin;
2816   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2817   ierr = PetscObjectSetOptionsPrefix((PetscObject)ts,prefix);CHKERRQ(ierr);
2818   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2819   ierr = SNESSetOptionsPrefix(snes,prefix);CHKERRQ(ierr);
2820   PetscFunctionReturn(0);
2821 }
2822 
2823 
2824 #undef __FUNCT__
2825 #define __FUNCT__ "TSAppendOptionsPrefix"
2826 /*@C
2827    TSAppendOptionsPrefix - Appends to the prefix used for searching for all
2828    TS options in the database.
2829 
2830    Logically Collective on TS
2831 
2832    Input Parameter:
2833 +  ts     - The TS context
2834 -  prefix - The prefix to prepend to all option names
2835 
2836    Notes:
2837    A hyphen (-) must NOT be given at the beginning of the prefix name.
2838    The first character of all runtime options is AUTOMATICALLY the
2839    hyphen.
2840 
2841    Level: advanced
2842 
2843 .keywords: TS, append, options, prefix, database
2844 
2845 .seealso: TSGetOptionsPrefix()
2846 
2847 @*/
2848 PetscErrorCode  TSAppendOptionsPrefix(TS ts,const char prefix[])
2849 {
2850   PetscErrorCode ierr;
2851   SNES           snes;
2852 
2853   PetscFunctionBegin;
2854   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2855   ierr = PetscObjectAppendOptionsPrefix((PetscObject)ts,prefix);CHKERRQ(ierr);
2856   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2857   ierr = SNESAppendOptionsPrefix(snes,prefix);CHKERRQ(ierr);
2858   PetscFunctionReturn(0);
2859 }
2860 
2861 #undef __FUNCT__
2862 #define __FUNCT__ "TSGetOptionsPrefix"
2863 /*@C
2864    TSGetOptionsPrefix - Sets the prefix used for searching for all
2865    TS options in the database.
2866 
2867    Not Collective
2868 
2869    Input Parameter:
2870 .  ts - The TS context
2871 
2872    Output Parameter:
2873 .  prefix - A pointer to the prefix string used
2874 
2875    Notes: On the fortran side, the user should pass in a string 'prifix' of
2876    sufficient length to hold the prefix.
2877 
2878    Level: intermediate
2879 
2880 .keywords: TS, get, options, prefix, database
2881 
2882 .seealso: TSAppendOptionsPrefix()
2883 @*/
2884 PetscErrorCode  TSGetOptionsPrefix(TS ts,const char *prefix[])
2885 {
2886   PetscErrorCode ierr;
2887 
2888   PetscFunctionBegin;
2889   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
2890   PetscValidPointer(prefix,2);
2891   ierr = PetscObjectGetOptionsPrefix((PetscObject)ts,prefix);CHKERRQ(ierr);
2892   PetscFunctionReturn(0);
2893 }
2894 
2895 #undef __FUNCT__
2896 #define __FUNCT__ "TSGetRHSJacobian"
2897 /*@C
2898    TSGetRHSJacobian - Returns the Jacobian J at the present timestep.
2899 
2900    Not Collective, but parallel objects are returned if TS is parallel
2901 
2902    Input Parameter:
2903 .  ts  - The TS context obtained from TSCreate()
2904 
2905    Output Parameters:
2906 +  J   - The Jacobian J of F, where U_t = G(U,t)
2907 .  M   - The preconditioner matrix, usually the same as J
2908 .  func - Function to compute the Jacobian of the RHS
2909 -  ctx - User-defined context for Jacobian evaluation routine
2910 
2911    Notes: You can pass in NULL for any return argument you do not need.
2912 
2913    Level: intermediate
2914 
2915 .seealso: TSGetTimeStep(), TSGetMatrices(), TSGetTime(), TSGetTimeStepNumber()
2916 
2917 .keywords: TS, timestep, get, matrix, Jacobian
2918 @*/
2919 PetscErrorCode  TSGetRHSJacobian(TS ts,Mat *J,Mat *M,TSRHSJacobian *func,void **ctx)
2920 {
2921   PetscErrorCode ierr;
2922   SNES           snes;
2923   DM             dm;
2924 
2925   PetscFunctionBegin;
2926   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2927   ierr = SNESGetJacobian(snes,J,M,NULL,NULL);CHKERRQ(ierr);
2928   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
2929   ierr = DMTSGetRHSJacobian(dm,func,ctx);CHKERRQ(ierr);
2930   PetscFunctionReturn(0);
2931 }
2932 
2933 #undef __FUNCT__
2934 #define __FUNCT__ "TSGetIJacobian"
2935 /*@C
2936    TSGetIJacobian - Returns the implicit Jacobian at the present timestep.
2937 
2938    Not Collective, but parallel objects are returned if TS is parallel
2939 
2940    Input Parameter:
2941 .  ts  - The TS context obtained from TSCreate()
2942 
2943    Output Parameters:
2944 +  A   - The Jacobian of F(t,U,U_t)
2945 .  B   - The preconditioner matrix, often the same as A
2946 .  f   - The function to compute the matrices
2947 - ctx - User-defined context for Jacobian evaluation routine
2948 
2949    Notes: You can pass in NULL for any return argument you do not need.
2950 
2951    Level: advanced
2952 
2953 .seealso: TSGetTimeStep(), TSGetRHSJacobian(), TSGetMatrices(), TSGetTime(), TSGetTimeStepNumber()
2954 
2955 .keywords: TS, timestep, get, matrix, Jacobian
2956 @*/
2957 PetscErrorCode  TSGetIJacobian(TS ts,Mat *A,Mat *B,TSIJacobian *f,void **ctx)
2958 {
2959   PetscErrorCode ierr;
2960   SNES           snes;
2961   DM             dm;
2962 
2963   PetscFunctionBegin;
2964   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
2965   ierr = SNESSetUpMatrices(snes);CHKERRQ(ierr);
2966   ierr = SNESGetJacobian(snes,A,B,NULL,NULL);CHKERRQ(ierr);
2967   ierr = TSGetDM(ts,&dm);CHKERRQ(ierr);
2968   ierr = DMTSGetIJacobian(dm,f,ctx);CHKERRQ(ierr);
2969   PetscFunctionReturn(0);
2970 }
2971 
2972 
2973 #undef __FUNCT__
2974 #define __FUNCT__ "TSMonitorDrawSolution"
2975 /*@C
2976    TSMonitorDrawSolution - Monitors progress of the TS solvers by calling
2977    VecView() for the solution at each timestep
2978 
2979    Collective on TS
2980 
2981    Input Parameters:
2982 +  ts - the TS context
2983 .  step - current time-step
2984 .  ptime - current time
2985 -  dummy - either a viewer or NULL
2986 
2987    Options Database:
2988 .   -ts_monitor_draw_solution_initial - show initial solution as well as current solution
2989 
2990    Notes: the initial solution and current solution are not displayed with a common axis scaling so generally the option -ts_monitor_draw_solution_initial
2991        will look bad
2992 
2993    Level: intermediate
2994 
2995 .keywords: TS,  vector, monitor, view
2996 
2997 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
2998 @*/
2999 PetscErrorCode  TSMonitorDrawSolution(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
3000 {
3001   PetscErrorCode   ierr;
3002   TSMonitorDrawCtx ictx = (TSMonitorDrawCtx)dummy;
3003   PetscDraw        draw;
3004 
3005   PetscFunctionBegin;
3006   if (!step && ictx->showinitial) {
3007     if (!ictx->initialsolution) {
3008       ierr = VecDuplicate(u,&ictx->initialsolution);CHKERRQ(ierr);
3009     }
3010     ierr = VecCopy(u,ictx->initialsolution);CHKERRQ(ierr);
3011   }
3012   if (!(((ictx->howoften > 0) && (!(step % ictx->howoften)) && (step > -1)) || ((ictx->howoften == -1) && (step == -1)))) PetscFunctionReturn(0);
3013 
3014   if (ictx->showinitial) {
3015     PetscReal pause;
3016     ierr = PetscViewerDrawGetPause(ictx->viewer,&pause);CHKERRQ(ierr);
3017     ierr = PetscViewerDrawSetPause(ictx->viewer,0.0);CHKERRQ(ierr);
3018     ierr = VecView(ictx->initialsolution,ictx->viewer);CHKERRQ(ierr);
3019     ierr = PetscViewerDrawSetPause(ictx->viewer,pause);CHKERRQ(ierr);
3020     ierr = PetscViewerDrawSetHold(ictx->viewer,PETSC_TRUE);CHKERRQ(ierr);
3021   }
3022   ierr = VecView(u,ictx->viewer);CHKERRQ(ierr);
3023   if (ictx->showtimestepandtime) {
3024     PetscReal xl,yl,xr,yr,tw,w,h;
3025     char      time[32];
3026     size_t    len;
3027 
3028     ierr = PetscViewerDrawGetDraw(ictx->viewer,0,&draw);CHKERRQ(ierr);
3029     ierr = PetscSNPrintf(time,32,"Timestep %d Time %f",(int)step,(double)ptime);CHKERRQ(ierr);
3030     ierr = PetscDrawGetCoordinates(draw,&xl,&yl,&xr,&yr);CHKERRQ(ierr);
3031     ierr =  PetscStrlen(time,&len);CHKERRQ(ierr);
3032     ierr = PetscDrawStringGetSize(draw,&tw,NULL);CHKERRQ(ierr);
3033     w    = xl + .5*(xr - xl) - .5*len*tw;
3034     h    = yl + .95*(yr - yl);
3035     ierr = PetscDrawString(draw,w,h,PETSC_DRAW_BLACK,time);CHKERRQ(ierr);
3036     ierr = PetscDrawFlush(draw);CHKERRQ(ierr);
3037   }
3038 
3039   if (ictx->showinitial) {
3040     ierr = PetscViewerDrawSetHold(ictx->viewer,PETSC_FALSE);CHKERRQ(ierr);
3041   }
3042   PetscFunctionReturn(0);
3043 }
3044 
3045 #undef __FUNCT__
3046 #define __FUNCT__ "TSMonitorDrawSolutionPhase"
3047 /*@C
3048    TSMonitorDrawSolutionPhase - Monitors progress of the TS solvers by plotting the solution as a phase diagram
3049 
3050    Collective on TS
3051 
3052    Input Parameters:
3053 +  ts - the TS context
3054 .  step - current time-step
3055 .  ptime - current time
3056 -  dummy - either a viewer or NULL
3057 
3058    Level: intermediate
3059 
3060 .keywords: TS,  vector, monitor, view
3061 
3062 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
3063 @*/
3064 PetscErrorCode  TSMonitorDrawSolutionPhase(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
3065 {
3066   PetscErrorCode    ierr;
3067   TSMonitorDrawCtx  ictx = (TSMonitorDrawCtx)dummy;
3068   PetscDraw         draw;
3069   MPI_Comm          comm;
3070   PetscInt          n;
3071   PetscMPIInt       size;
3072   PetscReal         xl,yl,xr,yr,tw,w,h;
3073   char              time[32];
3074   size_t            len;
3075   const PetscScalar *U;
3076 
3077   PetscFunctionBegin;
3078   ierr = PetscObjectGetComm((PetscObject)ts,&comm);CHKERRQ(ierr);
3079   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3080   if (size != 1) SETERRQ(comm,PETSC_ERR_SUP,"Only allowed for sequential runs");
3081   ierr = VecGetSize(u,&n);CHKERRQ(ierr);
3082   if (n != 2) SETERRQ(comm,PETSC_ERR_SUP,"Only for ODEs with two unknowns");
3083 
3084   ierr = PetscViewerDrawGetDraw(ictx->viewer,0,&draw);CHKERRQ(ierr);
3085 
3086   ierr = VecGetArrayRead(u,&U);CHKERRQ(ierr);
3087   if (!step) ictx->color++;
3088   ierr = PetscDrawPoint(draw,PetscRealPart(U[0]),PetscRealPart(U[1]),ictx->color);CHKERRQ(ierr);
3089   ierr = VecRestoreArrayRead(u,&U);CHKERRQ(ierr);
3090 
3091   if (ictx->showtimestepandtime) {
3092     ierr = PetscSNPrintf(time,32,"Timestep %d Time %f",(int)step,(double)ptime);CHKERRQ(ierr);
3093     ierr = PetscDrawGetCoordinates(draw,&xl,&yl,&xr,&yr);CHKERRQ(ierr);
3094     ierr = PetscStrlen(time,&len);CHKERRQ(ierr);
3095     ierr = PetscDrawStringGetSize(draw,&tw,NULL);CHKERRQ(ierr);
3096     w    = xl + .5*(xr - xl) - .5*len*tw;
3097     h    = yl + .95*(yr - yl);
3098     ierr = PetscDrawString(draw,w,h,PETSC_DRAW_BLACK,time);CHKERRQ(ierr);
3099   }
3100   ierr = PetscDrawFlush(draw);CHKERRQ(ierr);
3101   PetscFunctionReturn(0);
3102 }
3103 
3104 
3105 #undef __FUNCT__
3106 #define __FUNCT__ "TSMonitorDrawCtxDestroy"
3107 /*@C
3108    TSMonitorDrawCtxDestroy - Destroys the monitor context for TSMonitorDrawSolution()
3109 
3110    Collective on TS
3111 
3112    Input Parameters:
3113 .    ctx - the monitor context
3114 
3115    Level: intermediate
3116 
3117 .keywords: TS,  vector, monitor, view
3118 
3119 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorDrawSolution(), TSMonitorDrawError()
3120 @*/
3121 PetscErrorCode  TSMonitorDrawCtxDestroy(TSMonitorDrawCtx *ictx)
3122 {
3123   PetscErrorCode ierr;
3124 
3125   PetscFunctionBegin;
3126   ierr = PetscViewerDestroy(&(*ictx)->viewer);CHKERRQ(ierr);
3127   ierr = VecDestroy(&(*ictx)->initialsolution);CHKERRQ(ierr);
3128   ierr = PetscFree(*ictx);CHKERRQ(ierr);
3129   PetscFunctionReturn(0);
3130 }
3131 
3132 #undef __FUNCT__
3133 #define __FUNCT__ "TSMonitorDrawCtxCreate"
3134 /*@C
3135    TSMonitorDrawCtxCreate - Creates the monitor context for TSMonitorDrawCtx
3136 
3137    Collective on TS
3138 
3139    Input Parameter:
3140 .    ts - time-step context
3141 
3142    Output Patameter:
3143 .    ctx - the monitor context
3144 
3145    Options Database:
3146 .   -ts_monitor_draw_solution_initial - show initial solution as well as current solution
3147 
3148    Level: intermediate
3149 
3150 .keywords: TS,  vector, monitor, view
3151 
3152 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSMonitorDrawCtx()
3153 @*/
3154 PetscErrorCode  TSMonitorDrawCtxCreate(MPI_Comm comm,const char host[],const char label[],int x,int y,int m,int n,PetscInt howoften,TSMonitorDrawCtx *ctx)
3155 {
3156   PetscErrorCode   ierr;
3157 
3158   PetscFunctionBegin;
3159   ierr = PetscNew(struct _n_TSMonitorDrawCtx,ctx);CHKERRQ(ierr);
3160   ierr = PetscViewerDrawOpen(comm,host,label,x,y,m,n,&(*ctx)->viewer);CHKERRQ(ierr);
3161   ierr = PetscViewerSetFromOptions((*ctx)->viewer);CHKERRQ(ierr);
3162 
3163   (*ctx)->howoften    = howoften;
3164   (*ctx)->showinitial = PETSC_FALSE;
3165   ierr = PetscOptionsGetBool(NULL,"-ts_monitor_draw_solution_initial",&(*ctx)->showinitial,NULL);CHKERRQ(ierr);
3166 
3167   (*ctx)->showtimestepandtime = PETSC_FALSE;
3168   ierr = PetscOptionsGetBool(NULL,"-ts_monitor_draw_solution_show_time",&(*ctx)->showtimestepandtime,NULL);CHKERRQ(ierr);
3169   (*ctx)->color = PETSC_DRAW_WHITE;
3170   PetscFunctionReturn(0);
3171 }
3172 
3173 #undef __FUNCT__
3174 #define __FUNCT__ "TSMonitorDrawError"
3175 /*@C
3176    TSMonitorDrawError - Monitors progress of the TS solvers by calling
3177    VecView() for the error at each timestep
3178 
3179    Collective on TS
3180 
3181    Input Parameters:
3182 +  ts - the TS context
3183 .  step - current time-step
3184 .  ptime - current time
3185 -  dummy - either a viewer or NULL
3186 
3187    Level: intermediate
3188 
3189 .keywords: TS,  vector, monitor, view
3190 
3191 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
3192 @*/
3193 PetscErrorCode  TSMonitorDrawError(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
3194 {
3195   PetscErrorCode   ierr;
3196   TSMonitorDrawCtx ctx    = (TSMonitorDrawCtx)dummy;
3197   PetscViewer      viewer = ctx->viewer;
3198   Vec              work;
3199 
3200   PetscFunctionBegin;
3201   if (!(((ctx->howoften > 0) && (!(step % ctx->howoften)) && (step > -1)) || ((ctx->howoften == -1) && (step == -1)))) PetscFunctionReturn(0);
3202   ierr = VecDuplicate(u,&work);CHKERRQ(ierr);
3203   ierr = TSComputeSolutionFunction(ts,ptime,work);CHKERRQ(ierr);
3204   ierr = VecAXPY(work,-1.0,u);CHKERRQ(ierr);
3205   ierr = VecView(work,viewer);CHKERRQ(ierr);
3206   ierr = VecDestroy(&work);CHKERRQ(ierr);
3207   PetscFunctionReturn(0);
3208 }
3209 
3210 #include <petsc-private/dmimpl.h>
3211 #undef __FUNCT__
3212 #define __FUNCT__ "TSSetDM"
3213 /*@
3214    TSSetDM - Sets the DM that may be used by some preconditioners
3215 
3216    Logically Collective on TS and DM
3217 
3218    Input Parameters:
3219 +  ts - the preconditioner context
3220 -  dm - the dm
3221 
3222    Level: intermediate
3223 
3224 
3225 .seealso: TSGetDM(), SNESSetDM(), SNESGetDM()
3226 @*/
3227 PetscErrorCode  TSSetDM(TS ts,DM dm)
3228 {
3229   PetscErrorCode ierr;
3230   SNES           snes;
3231   DMTS           tsdm;
3232 
3233   PetscFunctionBegin;
3234   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3235   ierr = PetscObjectReference((PetscObject)dm);CHKERRQ(ierr);
3236   if (ts->dm) {               /* Move the DMTS context over to the new DM unless the new DM already has one */
3237     if (ts->dm->dmts && !dm->dmts) {
3238       ierr = DMCopyDMTS(ts->dm,dm);CHKERRQ(ierr);
3239       ierr = DMGetDMTS(ts->dm,&tsdm);CHKERRQ(ierr);
3240       if (tsdm->originaldm == ts->dm) { /* Grant write privileges to the replacement DM */
3241         tsdm->originaldm = dm;
3242       }
3243     }
3244     ierr = DMDestroy(&ts->dm);CHKERRQ(ierr);
3245   }
3246   ts->dm = dm;
3247 
3248   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
3249   ierr = SNESSetDM(snes,dm);CHKERRQ(ierr);
3250   PetscFunctionReturn(0);
3251 }
3252 
3253 #undef __FUNCT__
3254 #define __FUNCT__ "TSGetDM"
3255 /*@
3256    TSGetDM - Gets the DM that may be used by some preconditioners
3257 
3258    Not Collective
3259 
3260    Input Parameter:
3261 . ts - the preconditioner context
3262 
3263    Output Parameter:
3264 .  dm - the dm
3265 
3266    Level: intermediate
3267 
3268 
3269 .seealso: TSSetDM(), SNESSetDM(), SNESGetDM()
3270 @*/
3271 PetscErrorCode  TSGetDM(TS ts,DM *dm)
3272 {
3273   PetscErrorCode ierr;
3274 
3275   PetscFunctionBegin;
3276   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3277   if (!ts->dm) {
3278     ierr = DMShellCreate(PetscObjectComm((PetscObject)ts),&ts->dm);CHKERRQ(ierr);
3279     if (ts->snes) {ierr = SNESSetDM(ts->snes,ts->dm);CHKERRQ(ierr);}
3280   }
3281   *dm = ts->dm;
3282   PetscFunctionReturn(0);
3283 }
3284 
3285 #undef __FUNCT__
3286 #define __FUNCT__ "SNESTSFormFunction"
3287 /*@
3288    SNESTSFormFunction - Function to evaluate nonlinear residual
3289 
3290    Logically Collective on SNES
3291 
3292    Input Parameter:
3293 + snes - nonlinear solver
3294 . U - the current state at which to evaluate the residual
3295 - ctx - user context, must be a TS
3296 
3297    Output Parameter:
3298 . F - the nonlinear residual
3299 
3300    Notes:
3301    This function is not normally called by users and is automatically registered with the SNES used by TS.
3302    It is most frequently passed to MatFDColoringSetFunction().
3303 
3304    Level: advanced
3305 
3306 .seealso: SNESSetFunction(), MatFDColoringSetFunction()
3307 @*/
3308 PetscErrorCode  SNESTSFormFunction(SNES snes,Vec U,Vec F,void *ctx)
3309 {
3310   TS             ts = (TS)ctx;
3311   PetscErrorCode ierr;
3312 
3313   PetscFunctionBegin;
3314   PetscValidHeaderSpecific(snes,SNES_CLASSID,1);
3315   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
3316   PetscValidHeaderSpecific(F,VEC_CLASSID,3);
3317   PetscValidHeaderSpecific(ts,TS_CLASSID,4);
3318   ierr = (ts->ops->snesfunction)(snes,U,F,ts);CHKERRQ(ierr);
3319   PetscFunctionReturn(0);
3320 }
3321 
3322 #undef __FUNCT__
3323 #define __FUNCT__ "SNESTSFormJacobian"
3324 /*@
3325    SNESTSFormJacobian - Function to evaluate the Jacobian
3326 
3327    Collective on SNES
3328 
3329    Input Parameter:
3330 + snes - nonlinear solver
3331 . U - the current state at which to evaluate the residual
3332 - ctx - user context, must be a TS
3333 
3334    Output Parameter:
3335 + A - the Jacobian
3336 . B - the preconditioning matrix (may be the same as A)
3337 - flag - indicates any structure change in the matrix
3338 
3339    Notes:
3340    This function is not normally called by users and is automatically registered with the SNES used by TS.
3341 
3342    Level: developer
3343 
3344 .seealso: SNESSetJacobian()
3345 @*/
3346 PetscErrorCode  SNESTSFormJacobian(SNES snes,Vec U,Mat *A,Mat *B,MatStructure *flag,void *ctx)
3347 {
3348   TS             ts = (TS)ctx;
3349   PetscErrorCode ierr;
3350 
3351   PetscFunctionBegin;
3352   PetscValidHeaderSpecific(snes,SNES_CLASSID,1);
3353   PetscValidHeaderSpecific(U,VEC_CLASSID,2);
3354   PetscValidPointer(A,3);
3355   PetscValidHeaderSpecific(*A,MAT_CLASSID,3);
3356   PetscValidPointer(B,4);
3357   PetscValidHeaderSpecific(*B,MAT_CLASSID,4);
3358   PetscValidPointer(flag,5);
3359   PetscValidHeaderSpecific(ts,TS_CLASSID,6);
3360   ierr = (ts->ops->snesjacobian)(snes,U,A,B,flag,ts);CHKERRQ(ierr);
3361   PetscFunctionReturn(0);
3362 }
3363 
3364 #undef __FUNCT__
3365 #define __FUNCT__ "TSComputeRHSFunctionLinear"
3366 /*@C
3367    TSComputeRHSFunctionLinear - Evaluate the right hand side via the user-provided Jacobian, for linear problems only
3368 
3369    Collective on TS
3370 
3371    Input Arguments:
3372 +  ts - time stepping context
3373 .  t - time at which to evaluate
3374 .  U - state at which to evaluate
3375 -  ctx - context
3376 
3377    Output Arguments:
3378 .  F - right hand side
3379 
3380    Level: intermediate
3381 
3382    Notes:
3383    This function is intended to be passed to TSSetRHSFunction() to evaluate the right hand side for linear problems.
3384    The matrix (and optionally the evaluation context) should be passed to TSSetRHSJacobian().
3385 
3386 .seealso: TSSetRHSFunction(), TSSetRHSJacobian(), TSComputeRHSJacobianConstant()
3387 @*/
3388 PetscErrorCode TSComputeRHSFunctionLinear(TS ts,PetscReal t,Vec U,Vec F,void *ctx)
3389 {
3390   PetscErrorCode ierr;
3391   Mat            Arhs,Brhs;
3392   MatStructure   flg2;
3393 
3394   PetscFunctionBegin;
3395   ierr = TSGetRHSMats_Private(ts,&Arhs,&Brhs);CHKERRQ(ierr);
3396   ierr = TSComputeRHSJacobian(ts,t,U,&Arhs,&Brhs,&flg2);CHKERRQ(ierr);
3397   ierr = MatMult(Arhs,U,F);CHKERRQ(ierr);
3398   PetscFunctionReturn(0);
3399 }
3400 
3401 #undef __FUNCT__
3402 #define __FUNCT__ "TSComputeRHSJacobianConstant"
3403 /*@C
3404    TSComputeRHSJacobianConstant - Reuses a Jacobian that is time-independent.
3405 
3406    Collective on TS
3407 
3408    Input Arguments:
3409 +  ts - time stepping context
3410 .  t - time at which to evaluate
3411 .  U - state at which to evaluate
3412 -  ctx - context
3413 
3414    Output Arguments:
3415 +  A - pointer to operator
3416 .  B - pointer to preconditioning matrix
3417 -  flg - matrix structure flag
3418 
3419    Level: intermediate
3420 
3421    Notes:
3422    This function is intended to be passed to TSSetRHSJacobian() to evaluate the Jacobian for linear time-independent problems.
3423 
3424 .seealso: TSSetRHSFunction(), TSSetRHSJacobian(), TSComputeRHSFunctionLinear()
3425 @*/
3426 PetscErrorCode TSComputeRHSJacobianConstant(TS ts,PetscReal t,Vec U,Mat *A,Mat *B,MatStructure *flg,void *ctx)
3427 {
3428   PetscFunctionBegin;
3429   *flg = SAME_PRECONDITIONER;
3430   PetscFunctionReturn(0);
3431 }
3432 
3433 #undef __FUNCT__
3434 #define __FUNCT__ "TSComputeIFunctionLinear"
3435 /*@C
3436    TSComputeIFunctionLinear - Evaluate the left hand side via the user-provided Jacobian, for linear problems only
3437 
3438    Collective on TS
3439 
3440    Input Arguments:
3441 +  ts - time stepping context
3442 .  t - time at which to evaluate
3443 .  U - state at which to evaluate
3444 .  Udot - time derivative of state vector
3445 -  ctx - context
3446 
3447    Output Arguments:
3448 .  F - left hand side
3449 
3450    Level: intermediate
3451 
3452    Notes:
3453    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
3454    user is required to write their own TSComputeIFunction.
3455    This function is intended to be passed to TSSetIFunction() to evaluate the left hand side for linear problems.
3456    The matrix (and optionally the evaluation context) should be passed to TSSetIJacobian().
3457 
3458 .seealso: TSSetIFunction(), TSSetIJacobian(), TSComputeIJacobianConstant()
3459 @*/
3460 PetscErrorCode TSComputeIFunctionLinear(TS ts,PetscReal t,Vec U,Vec Udot,Vec F,void *ctx)
3461 {
3462   PetscErrorCode ierr;
3463   Mat            A,B;
3464   MatStructure   flg2;
3465 
3466   PetscFunctionBegin;
3467   ierr = TSGetIJacobian(ts,&A,&B,NULL,NULL);CHKERRQ(ierr);
3468   ierr = TSComputeIJacobian(ts,t,U,Udot,1.0,&A,&B,&flg2,PETSC_TRUE);CHKERRQ(ierr);
3469   ierr = MatMult(A,Udot,F);CHKERRQ(ierr);
3470   PetscFunctionReturn(0);
3471 }
3472 
3473 #undef __FUNCT__
3474 #define __FUNCT__ "TSComputeIJacobianConstant"
3475 /*@C
3476    TSComputeIJacobianConstant - Reuses a Jacobian that is time-independent.
3477 
3478    Collective on TS
3479 
3480    Input Arguments:
3481 +  ts - time stepping context
3482 .  t - time at which to evaluate
3483 .  U - state at which to evaluate
3484 .  Udot - time derivative of state vector
3485 .  shift - shift to apply
3486 -  ctx - context
3487 
3488    Output Arguments:
3489 +  A - pointer to operator
3490 .  B - pointer to preconditioning matrix
3491 -  flg - matrix structure flag
3492 
3493    Level: intermediate
3494 
3495    Notes:
3496    This function is intended to be passed to TSSetIJacobian() to evaluate the Jacobian for linear time-independent problems.
3497 
3498 .seealso: TSSetIFunction(), TSSetIJacobian(), TSComputeIFunctionLinear()
3499 @*/
3500 PetscErrorCode TSComputeIJacobianConstant(TS ts,PetscReal t,Vec U,Vec Udot,PetscReal shift,Mat *A,Mat *B,MatStructure *flg,void *ctx)
3501 {
3502   PetscFunctionBegin;
3503   *flg = SAME_PRECONDITIONER;
3504   PetscFunctionReturn(0);
3505 }
3506 #undef __FUNCT__
3507 #define __FUNCT__ "TSGetEquationType"
3508 /*@
3509    TSGetEquationType - Gets the type of the equation that TS is solving.
3510 
3511    Not Collective
3512 
3513    Input Parameter:
3514 .  ts - the TS context
3515 
3516    Output Parameter:
3517 .  equation_type - see TSEquatioType
3518 
3519    Level: beginner
3520 
3521 .keywords: TS, equation type
3522 
3523 .seealso: TSSetEquationType(), TSEquationType
3524 @*/
3525 PetscErrorCode  TSGetEquationType(TS ts,TSEquationType *equation_type)
3526 {
3527   PetscFunctionBegin;
3528   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3529   PetscValidPointer(equation_type,2);
3530   *equation_type = ts->equation_type;
3531   PetscFunctionReturn(0);
3532 }
3533 
3534 #undef __FUNCT__
3535 #define __FUNCT__ "TSSetEquationType"
3536 /*@
3537    TSSetEquationType - Sets the type of the equation that TS is solving.
3538 
3539    Not Collective
3540 
3541    Input Parameter:
3542 +  ts - the TS context
3543 .  equation_type - see TSEquatioType
3544 
3545    Level: advanced
3546 
3547 .keywords: TS, equation type
3548 
3549 .seealso: TSGetEquationType(), TSEquationType
3550 @*/
3551 PetscErrorCode  TSSetEquationType(TS ts,TSEquationType equation_type)
3552 {
3553   PetscFunctionBegin;
3554   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3555   ts->equation_type = equation_type;
3556   PetscFunctionReturn(0);
3557 }
3558 
3559 #undef __FUNCT__
3560 #define __FUNCT__ "TSGetConvergedReason"
3561 /*@
3562    TSGetConvergedReason - Gets the reason the TS iteration was stopped.
3563 
3564    Not Collective
3565 
3566    Input Parameter:
3567 .  ts - the TS context
3568 
3569    Output Parameter:
3570 .  reason - negative value indicates diverged, positive value converged, see TSConvergedReason or the
3571             manual pages for the individual convergence tests for complete lists
3572 
3573    Level: beginner
3574 
3575    Notes:
3576    Can only be called after the call to TSSolve() is complete.
3577 
3578 .keywords: TS, nonlinear, set, convergence, test
3579 
3580 .seealso: TSSetConvergenceTest(), TSConvergedReason
3581 @*/
3582 PetscErrorCode  TSGetConvergedReason(TS ts,TSConvergedReason *reason)
3583 {
3584   PetscFunctionBegin;
3585   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3586   PetscValidPointer(reason,2);
3587   *reason = ts->reason;
3588   PetscFunctionReturn(0);
3589 }
3590 
3591 #undef __FUNCT__
3592 #define __FUNCT__ "TSSetConvergedReason"
3593 /*@
3594    TSSetConvergedReason - Sets the reason for handling the convergence of TSSolve.
3595 
3596    Not Collective
3597 
3598    Input Parameter:
3599 +  ts - the TS context
3600 .  reason - negative value indicates diverged, positive value converged, see TSConvergedReason or the
3601             manual pages for the individual convergence tests for complete lists
3602 
3603    Level: advanced
3604 
3605    Notes:
3606    Can only be called during TSSolve() is active.
3607 
3608 .keywords: TS, nonlinear, set, convergence, test
3609 
3610 .seealso: TSConvergedReason
3611 @*/
3612 PetscErrorCode  TSSetConvergedReason(TS ts,TSConvergedReason reason)
3613 {
3614   PetscFunctionBegin;
3615   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3616   ts->reason = reason;
3617   PetscFunctionReturn(0);
3618 }
3619 
3620 #undef __FUNCT__
3621 #define __FUNCT__ "TSGetSolveTime"
3622 /*@
3623    TSGetSolveTime - Gets the time after a call to TSSolve()
3624 
3625    Not Collective
3626 
3627    Input Parameter:
3628 .  ts - the TS context
3629 
3630    Output Parameter:
3631 .  ftime - the final time. This time should correspond to the final time set with TSSetDuration()
3632 
3633    Level: beginner
3634 
3635    Notes:
3636    Can only be called after the call to TSSolve() is complete.
3637 
3638 .keywords: TS, nonlinear, set, convergence, test
3639 
3640 .seealso: TSSetConvergenceTest(), TSConvergedReason
3641 @*/
3642 PetscErrorCode  TSGetSolveTime(TS ts,PetscReal *ftime)
3643 {
3644   PetscFunctionBegin;
3645   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3646   PetscValidPointer(ftime,2);
3647   *ftime = ts->solvetime;
3648   PetscFunctionReturn(0);
3649 }
3650 
3651 #undef __FUNCT__
3652 #define __FUNCT__ "TSGetSNESIterations"
3653 /*@
3654    TSGetSNESIterations - Gets the total number of nonlinear iterations
3655    used by the time integrator.
3656 
3657    Not Collective
3658 
3659    Input Parameter:
3660 .  ts - TS context
3661 
3662    Output Parameter:
3663 .  nits - number of nonlinear iterations
3664 
3665    Notes:
3666    This counter is reset to zero for each successive call to TSSolve().
3667 
3668    Level: intermediate
3669 
3670 .keywords: TS, get, number, nonlinear, iterations
3671 
3672 .seealso:  TSGetKSPIterations()
3673 @*/
3674 PetscErrorCode TSGetSNESIterations(TS ts,PetscInt *nits)
3675 {
3676   PetscFunctionBegin;
3677   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3678   PetscValidIntPointer(nits,2);
3679   *nits = ts->snes_its;
3680   PetscFunctionReturn(0);
3681 }
3682 
3683 #undef __FUNCT__
3684 #define __FUNCT__ "TSGetKSPIterations"
3685 /*@
3686    TSGetKSPIterations - Gets the total number of linear iterations
3687    used by the time integrator.
3688 
3689    Not Collective
3690 
3691    Input Parameter:
3692 .  ts - TS context
3693 
3694    Output Parameter:
3695 .  lits - number of linear iterations
3696 
3697    Notes:
3698    This counter is reset to zero for each successive call to TSSolve().
3699 
3700    Level: intermediate
3701 
3702 .keywords: TS, get, number, linear, iterations
3703 
3704 .seealso:  TSGetSNESIterations(), SNESGetKSPIterations()
3705 @*/
3706 PetscErrorCode TSGetKSPIterations(TS ts,PetscInt *lits)
3707 {
3708   PetscFunctionBegin;
3709   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3710   PetscValidIntPointer(lits,2);
3711   *lits = ts->ksp_its;
3712   PetscFunctionReturn(0);
3713 }
3714 
3715 #undef __FUNCT__
3716 #define __FUNCT__ "TSGetStepRejections"
3717 /*@
3718    TSGetStepRejections - Gets the total number of rejected steps.
3719 
3720    Not Collective
3721 
3722    Input Parameter:
3723 .  ts - TS context
3724 
3725    Output Parameter:
3726 .  rejects - number of steps rejected
3727 
3728    Notes:
3729    This counter is reset to zero for each successive call to TSSolve().
3730 
3731    Level: intermediate
3732 
3733 .keywords: TS, get, number
3734 
3735 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetSNESFailures(), TSSetMaxSNESFailures(), TSSetErrorIfStepFails()
3736 @*/
3737 PetscErrorCode TSGetStepRejections(TS ts,PetscInt *rejects)
3738 {
3739   PetscFunctionBegin;
3740   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3741   PetscValidIntPointer(rejects,2);
3742   *rejects = ts->reject;
3743   PetscFunctionReturn(0);
3744 }
3745 
3746 #undef __FUNCT__
3747 #define __FUNCT__ "TSGetSNESFailures"
3748 /*@
3749    TSGetSNESFailures - Gets the total number of failed SNES solves
3750 
3751    Not Collective
3752 
3753    Input Parameter:
3754 .  ts - TS context
3755 
3756    Output Parameter:
3757 .  fails - number of failed nonlinear solves
3758 
3759    Notes:
3760    This counter is reset to zero for each successive call to TSSolve().
3761 
3762    Level: intermediate
3763 
3764 .keywords: TS, get, number
3765 
3766 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetStepRejections(), TSSetMaxSNESFailures()
3767 @*/
3768 PetscErrorCode TSGetSNESFailures(TS ts,PetscInt *fails)
3769 {
3770   PetscFunctionBegin;
3771   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3772   PetscValidIntPointer(fails,2);
3773   *fails = ts->num_snes_failures;
3774   PetscFunctionReturn(0);
3775 }
3776 
3777 #undef __FUNCT__
3778 #define __FUNCT__ "TSSetMaxStepRejections"
3779 /*@
3780    TSSetMaxStepRejections - Sets the maximum number of step rejections before a step fails
3781 
3782    Not Collective
3783 
3784    Input Parameter:
3785 +  ts - TS context
3786 -  rejects - maximum number of rejected steps, pass -1 for unlimited
3787 
3788    Notes:
3789    The counter is reset to zero for each step
3790 
3791    Options Database Key:
3792  .  -ts_max_reject - Maximum number of step rejections before a step fails
3793 
3794    Level: intermediate
3795 
3796 .keywords: TS, set, maximum, number
3797 
3798 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxSNESFailures(), TSGetStepRejections(), TSGetSNESFailures(), TSSetErrorIfStepFails(), TSGetConvergedReason()
3799 @*/
3800 PetscErrorCode TSSetMaxStepRejections(TS ts,PetscInt rejects)
3801 {
3802   PetscFunctionBegin;
3803   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3804   ts->max_reject = rejects;
3805   PetscFunctionReturn(0);
3806 }
3807 
3808 #undef __FUNCT__
3809 #define __FUNCT__ "TSSetMaxSNESFailures"
3810 /*@
3811    TSSetMaxSNESFailures - Sets the maximum number of failed SNES solves
3812 
3813    Not Collective
3814 
3815    Input Parameter:
3816 +  ts - TS context
3817 -  fails - maximum number of failed nonlinear solves, pass -1 for unlimited
3818 
3819    Notes:
3820    The counter is reset to zero for each successive call to TSSolve().
3821 
3822    Options Database Key:
3823  .  -ts_max_snes_failures - Maximum number of nonlinear solve failures
3824 
3825    Level: intermediate
3826 
3827 .keywords: TS, set, maximum, number
3828 
3829 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetStepRejections(), TSGetSNESFailures(), SNESGetConvergedReason(), TSGetConvergedReason()
3830 @*/
3831 PetscErrorCode TSSetMaxSNESFailures(TS ts,PetscInt fails)
3832 {
3833   PetscFunctionBegin;
3834   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3835   ts->max_snes_failures = fails;
3836   PetscFunctionReturn(0);
3837 }
3838 
3839 #undef __FUNCT__
3840 #define __FUNCT__ "TSSetErrorIfStepFails()"
3841 /*@
3842    TSSetErrorIfStepFails - Error if no step succeeds
3843 
3844    Not Collective
3845 
3846    Input Parameter:
3847 +  ts - TS context
3848 -  err - PETSC_TRUE to error if no step succeeds, PETSC_FALSE to return without failure
3849 
3850    Options Database Key:
3851  .  -ts_error_if_step_fails - Error if no step succeeds
3852 
3853    Level: intermediate
3854 
3855 .keywords: TS, set, error
3856 
3857 .seealso:  TSGetSNESIterations(), TSGetKSPIterations(), TSSetMaxStepRejections(), TSGetStepRejections(), TSGetSNESFailures(), TSSetErrorIfStepFails(), TSGetConvergedReason()
3858 @*/
3859 PetscErrorCode TSSetErrorIfStepFails(TS ts,PetscBool err)
3860 {
3861   PetscFunctionBegin;
3862   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3863   ts->errorifstepfailed = err;
3864   PetscFunctionReturn(0);
3865 }
3866 
3867 #undef __FUNCT__
3868 #define __FUNCT__ "TSMonitorSolutionBinary"
3869 /*@C
3870    TSMonitorSolutionBinary - Monitors progress of the TS solvers by VecView() for the solution at each timestep. Normally the viewer is a binary file
3871 
3872    Collective on TS
3873 
3874    Input Parameters:
3875 +  ts - the TS context
3876 .  step - current time-step
3877 .  ptime - current time
3878 .  u - current state
3879 -  viewer - binary viewer
3880 
3881    Level: intermediate
3882 
3883 .keywords: TS,  vector, monitor, view
3884 
3885 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
3886 @*/
3887 PetscErrorCode  TSMonitorSolutionBinary(TS ts,PetscInt step,PetscReal ptime,Vec u,void *viewer)
3888 {
3889   PetscErrorCode ierr;
3890   PetscViewer    v = (PetscViewer)viewer;
3891 
3892   PetscFunctionBegin;
3893   ierr = VecView(u,v);CHKERRQ(ierr);
3894   PetscFunctionReturn(0);
3895 }
3896 
3897 #undef __FUNCT__
3898 #define __FUNCT__ "TSMonitorSolutionVTK"
3899 /*@C
3900    TSMonitorSolutionVTK - Monitors progress of the TS solvers by VecView() for the solution at each timestep.
3901 
3902    Collective on TS
3903 
3904    Input Parameters:
3905 +  ts - the TS context
3906 .  step - current time-step
3907 .  ptime - current time
3908 .  u - current state
3909 -  filenametemplate - string containing a format specifier for the integer time step (e.g. %03D)
3910 
3911    Level: intermediate
3912 
3913    Notes:
3914    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.
3915    These are named according to the file name template.
3916 
3917    This function is normally passed as an argument to TSMonitorSet() along with TSMonitorSolutionVTKDestroy().
3918 
3919 .keywords: TS,  vector, monitor, view
3920 
3921 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
3922 @*/
3923 PetscErrorCode TSMonitorSolutionVTK(TS ts,PetscInt step,PetscReal ptime,Vec u,void *filenametemplate)
3924 {
3925   PetscErrorCode ierr;
3926   char           filename[PETSC_MAX_PATH_LEN];
3927   PetscViewer    viewer;
3928 
3929   PetscFunctionBegin;
3930   ierr = PetscSNPrintf(filename,sizeof(filename),(const char*)filenametemplate,step);CHKERRQ(ierr);
3931   ierr = PetscViewerVTKOpen(PetscObjectComm((PetscObject)ts),filename,FILE_MODE_WRITE,&viewer);CHKERRQ(ierr);
3932   ierr = VecView(u,viewer);CHKERRQ(ierr);
3933   ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
3934   PetscFunctionReturn(0);
3935 }
3936 
3937 #undef __FUNCT__
3938 #define __FUNCT__ "TSMonitorSolutionVTKDestroy"
3939 /*@C
3940    TSMonitorSolutionVTKDestroy - Destroy context for monitoring
3941 
3942    Collective on TS
3943 
3944    Input Parameters:
3945 .  filenametemplate - string containing a format specifier for the integer time step (e.g. %03D)
3946 
3947    Level: intermediate
3948 
3949    Note:
3950    This function is normally passed to TSMonitorSet() along with TSMonitorSolutionVTK().
3951 
3952 .keywords: TS,  vector, monitor, view
3953 
3954 .seealso: TSMonitorSet(), TSMonitorSolutionVTK()
3955 @*/
3956 PetscErrorCode TSMonitorSolutionVTKDestroy(void *filenametemplate)
3957 {
3958   PetscErrorCode ierr;
3959 
3960   PetscFunctionBegin;
3961   ierr = PetscFree(*(char**)filenametemplate);CHKERRQ(ierr);
3962   PetscFunctionReturn(0);
3963 }
3964 
3965 #undef __FUNCT__
3966 #define __FUNCT__ "TSGetTSAdapt"
3967 /*@
3968    TSGetTSAdapt - Get the adaptive controller context for the current method
3969 
3970    Collective on TS if controller has not been created yet
3971 
3972    Input Arguments:
3973 .  ts - time stepping context
3974 
3975    Output Arguments:
3976 .  adapt - adaptive controller
3977 
3978    Level: intermediate
3979 
3980 .seealso: TSAdapt, TSAdaptSetType(), TSAdaptChoose()
3981 @*/
3982 PetscErrorCode TSGetTSAdapt(TS ts,TSAdapt *adapt)
3983 {
3984   PetscErrorCode ierr;
3985 
3986   PetscFunctionBegin;
3987   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
3988   PetscValidPointer(adapt,2);
3989   if (!ts->adapt) {
3990     ierr = TSAdaptCreate(PetscObjectComm((PetscObject)ts),&ts->adapt);CHKERRQ(ierr);
3991     ierr = PetscLogObjectParent(ts,ts->adapt);CHKERRQ(ierr);
3992     ierr = PetscObjectIncrementTabLevel((PetscObject)ts->adapt,(PetscObject)ts,1);CHKERRQ(ierr);
3993   }
3994   *adapt = ts->adapt;
3995   PetscFunctionReturn(0);
3996 }
3997 
3998 #undef __FUNCT__
3999 #define __FUNCT__ "TSSetTolerances"
4000 /*@
4001    TSSetTolerances - Set tolerances for local truncation error when using adaptive controller
4002 
4003    Logically Collective
4004 
4005    Input Arguments:
4006 +  ts - time integration context
4007 .  atol - scalar absolute tolerances, PETSC_DECIDE to leave current value
4008 .  vatol - vector of absolute tolerances or NULL, used in preference to atol if present
4009 .  rtol - scalar relative tolerances, PETSC_DECIDE to leave current value
4010 -  vrtol - vector of relative tolerances or NULL, used in preference to atol if present
4011 
4012    Level: beginner
4013 
4014 .seealso: TS, TSAdapt, TSVecNormWRMS(), TSGetTolerances()
4015 @*/
4016 PetscErrorCode TSSetTolerances(TS ts,PetscReal atol,Vec vatol,PetscReal rtol,Vec vrtol)
4017 {
4018   PetscErrorCode ierr;
4019 
4020   PetscFunctionBegin;
4021   if (atol != PETSC_DECIDE && atol != PETSC_DEFAULT) ts->atol = atol;
4022   if (vatol) {
4023     ierr = PetscObjectReference((PetscObject)vatol);CHKERRQ(ierr);
4024     ierr = VecDestroy(&ts->vatol);CHKERRQ(ierr);
4025 
4026     ts->vatol = vatol;
4027   }
4028   if (rtol != PETSC_DECIDE && rtol != PETSC_DEFAULT) ts->rtol = rtol;
4029   if (vrtol) {
4030     ierr = PetscObjectReference((PetscObject)vrtol);CHKERRQ(ierr);
4031     ierr = VecDestroy(&ts->vrtol);CHKERRQ(ierr);
4032 
4033     ts->vrtol = vrtol;
4034   }
4035   PetscFunctionReturn(0);
4036 }
4037 
4038 #undef __FUNCT__
4039 #define __FUNCT__ "TSGetTolerances"
4040 /*@
4041    TSGetTolerances - Get tolerances for local truncation error when using adaptive controller
4042 
4043    Logically Collective
4044 
4045    Input Arguments:
4046 .  ts - time integration context
4047 
4048    Output Arguments:
4049 +  atol - scalar absolute tolerances, NULL to ignore
4050 .  vatol - vector of absolute tolerances, NULL to ignore
4051 .  rtol - scalar relative tolerances, NULL to ignore
4052 -  vrtol - vector of relative tolerances, NULL to ignore
4053 
4054    Level: beginner
4055 
4056 .seealso: TS, TSAdapt, TSVecNormWRMS(), TSSetTolerances()
4057 @*/
4058 PetscErrorCode TSGetTolerances(TS ts,PetscReal *atol,Vec *vatol,PetscReal *rtol,Vec *vrtol)
4059 {
4060   PetscFunctionBegin;
4061   if (atol)  *atol  = ts->atol;
4062   if (vatol) *vatol = ts->vatol;
4063   if (rtol)  *rtol  = ts->rtol;
4064   if (vrtol) *vrtol = ts->vrtol;
4065   PetscFunctionReturn(0);
4066 }
4067 
4068 #undef __FUNCT__
4069 #define __FUNCT__ "TSErrorNormWRMS"
4070 /*@
4071    TSErrorNormWRMS - compute a weighted norm of the difference between a vector and the current state
4072 
4073    Collective on TS
4074 
4075    Input Arguments:
4076 +  ts - time stepping context
4077 -  Y - state vector to be compared to ts->vec_sol
4078 
4079    Output Arguments:
4080 .  norm - weighted norm, a value of 1.0 is considered small
4081 
4082    Level: developer
4083 
4084 .seealso: TSSetTolerances()
4085 @*/
4086 PetscErrorCode TSErrorNormWRMS(TS ts,Vec Y,PetscReal *norm)
4087 {
4088   PetscErrorCode    ierr;
4089   PetscInt          i,n,N;
4090   const PetscScalar *u,*y;
4091   Vec               U;
4092   PetscReal         sum,gsum;
4093 
4094   PetscFunctionBegin;
4095   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4096   PetscValidHeaderSpecific(Y,VEC_CLASSID,2);
4097   PetscValidPointer(norm,3);
4098   U = ts->vec_sol;
4099   PetscCheckSameTypeAndComm(U,1,Y,2);
4100   if (U == Y) SETERRQ(PetscObjectComm((PetscObject)U),PETSC_ERR_ARG_IDN,"Y cannot be the TS solution vector");
4101 
4102   ierr = VecGetSize(U,&N);CHKERRQ(ierr);
4103   ierr = VecGetLocalSize(U,&n);CHKERRQ(ierr);
4104   ierr = VecGetArrayRead(U,&u);CHKERRQ(ierr);
4105   ierr = VecGetArrayRead(Y,&y);CHKERRQ(ierr);
4106   sum  = 0.;
4107   if (ts->vatol && ts->vrtol) {
4108     const PetscScalar *atol,*rtol;
4109     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
4110     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
4111     for (i=0; i<n; i++) {
4112       PetscReal tol = PetscRealPart(atol[i]) + PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
4113       sum += PetscSqr(PetscAbsScalar(y[i] - u[i]) / tol);
4114     }
4115     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
4116     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
4117   } else if (ts->vatol) {       /* vector atol, scalar rtol */
4118     const PetscScalar *atol;
4119     ierr = VecGetArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
4120     for (i=0; i<n; i++) {
4121       PetscReal tol = PetscRealPart(atol[i]) + ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
4122       sum += PetscSqr(PetscAbsScalar(y[i] - u[i]) / tol);
4123     }
4124     ierr = VecRestoreArrayRead(ts->vatol,&atol);CHKERRQ(ierr);
4125   } else if (ts->vrtol) {       /* scalar atol, vector rtol */
4126     const PetscScalar *rtol;
4127     ierr = VecGetArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
4128     for (i=0; i<n; i++) {
4129       PetscReal tol = ts->atol + PetscRealPart(rtol[i]) * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
4130       sum += PetscSqr(PetscAbsScalar(y[i] - u[i]) / tol);
4131     }
4132     ierr = VecRestoreArrayRead(ts->vrtol,&rtol);CHKERRQ(ierr);
4133   } else {                      /* scalar atol, scalar rtol */
4134     for (i=0; i<n; i++) {
4135       PetscReal tol = ts->atol + ts->rtol * PetscMax(PetscAbsScalar(u[i]),PetscAbsScalar(y[i]));
4136       sum += PetscSqr(PetscAbsScalar(y[i] - u[i]) / tol);
4137     }
4138   }
4139   ierr = VecRestoreArrayRead(U,&u);CHKERRQ(ierr);
4140   ierr = VecRestoreArrayRead(Y,&y);CHKERRQ(ierr);
4141 
4142   ierr  = MPI_Allreduce(&sum,&gsum,1,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
4143   *norm = PetscSqrtReal(gsum / N);
4144   if (PetscIsInfOrNanScalar(*norm)) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_FP,"Infinite or not-a-number generated in norm");
4145   PetscFunctionReturn(0);
4146 }
4147 
4148 #undef __FUNCT__
4149 #define __FUNCT__ "TSSetCFLTimeLocal"
4150 /*@
4151    TSSetCFLTimeLocal - Set the local CFL constraint relative to forward Euler
4152 
4153    Logically Collective on TS
4154 
4155    Input Arguments:
4156 +  ts - time stepping context
4157 -  cfltime - maximum stable time step if using forward Euler (value can be different on each process)
4158 
4159    Note:
4160    After calling this function, the global CFL time can be obtained by calling TSGetCFLTime()
4161 
4162    Level: intermediate
4163 
4164 .seealso: TSGetCFLTime(), TSADAPTCFL
4165 @*/
4166 PetscErrorCode TSSetCFLTimeLocal(TS ts,PetscReal cfltime)
4167 {
4168   PetscFunctionBegin;
4169   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4170   ts->cfltime_local = cfltime;
4171   ts->cfltime       = -1.;
4172   PetscFunctionReturn(0);
4173 }
4174 
4175 #undef __FUNCT__
4176 #define __FUNCT__ "TSGetCFLTime"
4177 /*@
4178    TSGetCFLTime - Get the maximum stable time step according to CFL criteria applied to forward Euler
4179 
4180    Collective on TS
4181 
4182    Input Arguments:
4183 .  ts - time stepping context
4184 
4185    Output Arguments:
4186 .  cfltime - maximum stable time step for forward Euler
4187 
4188    Level: advanced
4189 
4190 .seealso: TSSetCFLTimeLocal()
4191 @*/
4192 PetscErrorCode TSGetCFLTime(TS ts,PetscReal *cfltime)
4193 {
4194   PetscErrorCode ierr;
4195 
4196   PetscFunctionBegin;
4197   if (ts->cfltime < 0) {
4198     ierr = MPI_Allreduce(&ts->cfltime_local,&ts->cfltime,1,MPIU_REAL,MPIU_MIN,PetscObjectComm((PetscObject)ts));CHKERRQ(ierr);
4199   }
4200   *cfltime = ts->cfltime;
4201   PetscFunctionReturn(0);
4202 }
4203 
4204 #undef __FUNCT__
4205 #define __FUNCT__ "TSVISetVariableBounds"
4206 /*@
4207    TSVISetVariableBounds - Sets the lower and upper bounds for the solution vector. xl <= x <= xu
4208 
4209    Input Parameters:
4210 .  ts   - the TS context.
4211 .  xl   - lower bound.
4212 .  xu   - upper bound.
4213 
4214    Notes:
4215    If this routine is not called then the lower and upper bounds are set to
4216    SNES_VI_NINF and SNES_VI_INF respectively during SNESSetUp().
4217 
4218    Level: advanced
4219 
4220 @*/
4221 PetscErrorCode TSVISetVariableBounds(TS ts, Vec xl, Vec xu)
4222 {
4223   PetscErrorCode ierr;
4224   SNES           snes;
4225 
4226   PetscFunctionBegin;
4227   ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr);
4228   ierr = SNESVISetVariableBounds(snes,xl,xu);CHKERRQ(ierr);
4229   PetscFunctionReturn(0);
4230 }
4231 
4232 #if defined(PETSC_HAVE_MATLAB_ENGINE)
4233 #include <mex.h>
4234 
4235 typedef struct {char *funcname; mxArray *ctx;} TSMatlabContext;
4236 
4237 #undef __FUNCT__
4238 #define __FUNCT__ "TSComputeFunction_Matlab"
4239 /*
4240    TSComputeFunction_Matlab - Calls the function that has been set with
4241                          TSSetFunctionMatlab().
4242 
4243    Collective on TS
4244 
4245    Input Parameters:
4246 +  snes - the TS context
4247 -  u - input vector
4248 
4249    Output Parameter:
4250 .  y - function vector, as set by TSSetFunction()
4251 
4252    Notes:
4253    TSComputeFunction() is typically used within nonlinear solvers
4254    implementations, so most users would not generally call this routine
4255    themselves.
4256 
4257    Level: developer
4258 
4259 .keywords: TS, nonlinear, compute, function
4260 
4261 .seealso: TSSetFunction(), TSGetFunction()
4262 */
4263 PetscErrorCode  TSComputeFunction_Matlab(TS snes,PetscReal time,Vec u,Vec udot,Vec y, void *ctx)
4264 {
4265   PetscErrorCode  ierr;
4266   TSMatlabContext *sctx = (TSMatlabContext*)ctx;
4267   int             nlhs  = 1,nrhs = 7;
4268   mxArray         *plhs[1],*prhs[7];
4269   long long int   lx = 0,lxdot = 0,ly = 0,ls = 0;
4270 
4271   PetscFunctionBegin;
4272   PetscValidHeaderSpecific(snes,TS_CLASSID,1);
4273   PetscValidHeaderSpecific(u,VEC_CLASSID,3);
4274   PetscValidHeaderSpecific(udot,VEC_CLASSID,4);
4275   PetscValidHeaderSpecific(y,VEC_CLASSID,5);
4276   PetscCheckSameComm(snes,1,u,3);
4277   PetscCheckSameComm(snes,1,y,5);
4278 
4279   ierr = PetscMemcpy(&ls,&snes,sizeof(snes));CHKERRQ(ierr);
4280   ierr = PetscMemcpy(&lx,&u,sizeof(u));CHKERRQ(ierr);
4281   ierr = PetscMemcpy(&lxdot,&udot,sizeof(udot));CHKERRQ(ierr);
4282   ierr = PetscMemcpy(&ly,&y,sizeof(u));CHKERRQ(ierr);
4283 
4284   prhs[0] =  mxCreateDoubleScalar((double)ls);
4285   prhs[1] =  mxCreateDoubleScalar(time);
4286   prhs[2] =  mxCreateDoubleScalar((double)lx);
4287   prhs[3] =  mxCreateDoubleScalar((double)lxdot);
4288   prhs[4] =  mxCreateDoubleScalar((double)ly);
4289   prhs[5] =  mxCreateString(sctx->funcname);
4290   prhs[6] =  sctx->ctx;
4291   ierr    =  mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscTSComputeFunctionInternal");CHKERRQ(ierr);
4292   ierr    =  mxGetScalar(plhs[0]);CHKERRQ(ierr);
4293   mxDestroyArray(prhs[0]);
4294   mxDestroyArray(prhs[1]);
4295   mxDestroyArray(prhs[2]);
4296   mxDestroyArray(prhs[3]);
4297   mxDestroyArray(prhs[4]);
4298   mxDestroyArray(prhs[5]);
4299   mxDestroyArray(plhs[0]);
4300   PetscFunctionReturn(0);
4301 }
4302 
4303 
4304 #undef __FUNCT__
4305 #define __FUNCT__ "TSSetFunctionMatlab"
4306 /*
4307    TSSetFunctionMatlab - Sets the function evaluation routine and function
4308    vector for use by the TS routines in solving ODEs
4309    equations from MATLAB. Here the function is a string containing the name of a MATLAB function
4310 
4311    Logically Collective on TS
4312 
4313    Input Parameters:
4314 +  ts - the TS context
4315 -  func - function evaluation routine
4316 
4317    Calling sequence of func:
4318 $    func (TS ts,PetscReal time,Vec u,Vec udot,Vec f,void *ctx);
4319 
4320    Level: beginner
4321 
4322 .keywords: TS, nonlinear, set, function
4323 
4324 .seealso: TSGetFunction(), TSComputeFunction(), TSSetJacobian(), TSSetFunction()
4325 */
4326 PetscErrorCode  TSSetFunctionMatlab(TS ts,const char *func,mxArray *ctx)
4327 {
4328   PetscErrorCode  ierr;
4329   TSMatlabContext *sctx;
4330 
4331   PetscFunctionBegin;
4332   /* currently sctx is memory bleed */
4333   ierr = PetscMalloc(sizeof(TSMatlabContext),&sctx);CHKERRQ(ierr);
4334   ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr);
4335   /*
4336      This should work, but it doesn't
4337   sctx->ctx = ctx;
4338   mexMakeArrayPersistent(sctx->ctx);
4339   */
4340   sctx->ctx = mxDuplicateArray(ctx);
4341 
4342   ierr = TSSetIFunction(ts,NULL,TSComputeFunction_Matlab,sctx);CHKERRQ(ierr);
4343   PetscFunctionReturn(0);
4344 }
4345 
4346 #undef __FUNCT__
4347 #define __FUNCT__ "TSComputeJacobian_Matlab"
4348 /*
4349    TSComputeJacobian_Matlab - Calls the function that has been set with
4350                          TSSetJacobianMatlab().
4351 
4352    Collective on TS
4353 
4354    Input Parameters:
4355 +  ts - the TS context
4356 .  u - input vector
4357 .  A, B - the matrices
4358 -  ctx - user context
4359 
4360    Output Parameter:
4361 .  flag - structure of the matrix
4362 
4363    Level: developer
4364 
4365 .keywords: TS, nonlinear, compute, function
4366 
4367 .seealso: TSSetFunction(), TSGetFunction()
4368 @*/
4369 PetscErrorCode  TSComputeJacobian_Matlab(TS ts,PetscReal time,Vec u,Vec udot,PetscReal shift,Mat *A,Mat *B,MatStructure *flag, void *ctx)
4370 {
4371   PetscErrorCode  ierr;
4372   TSMatlabContext *sctx = (TSMatlabContext*)ctx;
4373   int             nlhs  = 2,nrhs = 9;
4374   mxArray         *plhs[2],*prhs[9];
4375   long long int   lx = 0,lxdot = 0,lA = 0,ls = 0, lB = 0;
4376 
4377   PetscFunctionBegin;
4378   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4379   PetscValidHeaderSpecific(u,VEC_CLASSID,3);
4380 
4381   /* call Matlab function in ctx with arguments u and y */
4382 
4383   ierr = PetscMemcpy(&ls,&ts,sizeof(ts));CHKERRQ(ierr);
4384   ierr = PetscMemcpy(&lx,&u,sizeof(u));CHKERRQ(ierr);
4385   ierr = PetscMemcpy(&lxdot,&udot,sizeof(u));CHKERRQ(ierr);
4386   ierr = PetscMemcpy(&lA,A,sizeof(u));CHKERRQ(ierr);
4387   ierr = PetscMemcpy(&lB,B,sizeof(u));CHKERRQ(ierr);
4388 
4389   prhs[0] =  mxCreateDoubleScalar((double)ls);
4390   prhs[1] =  mxCreateDoubleScalar((double)time);
4391   prhs[2] =  mxCreateDoubleScalar((double)lx);
4392   prhs[3] =  mxCreateDoubleScalar((double)lxdot);
4393   prhs[4] =  mxCreateDoubleScalar((double)shift);
4394   prhs[5] =  mxCreateDoubleScalar((double)lA);
4395   prhs[6] =  mxCreateDoubleScalar((double)lB);
4396   prhs[7] =  mxCreateString(sctx->funcname);
4397   prhs[8] =  sctx->ctx;
4398   ierr    =  mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscTSComputeJacobianInternal");CHKERRQ(ierr);
4399   ierr    =  mxGetScalar(plhs[0]);CHKERRQ(ierr);
4400   *flag   =  (MatStructure) mxGetScalar(plhs[1]);CHKERRQ(ierr);
4401   mxDestroyArray(prhs[0]);
4402   mxDestroyArray(prhs[1]);
4403   mxDestroyArray(prhs[2]);
4404   mxDestroyArray(prhs[3]);
4405   mxDestroyArray(prhs[4]);
4406   mxDestroyArray(prhs[5]);
4407   mxDestroyArray(prhs[6]);
4408   mxDestroyArray(prhs[7]);
4409   mxDestroyArray(plhs[0]);
4410   mxDestroyArray(plhs[1]);
4411   PetscFunctionReturn(0);
4412 }
4413 
4414 
4415 #undef __FUNCT__
4416 #define __FUNCT__ "TSSetJacobianMatlab"
4417 /*
4418    TSSetJacobianMatlab - Sets the Jacobian function evaluation routine and two empty Jacobian matrices
4419    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
4420 
4421    Logically Collective on TS
4422 
4423    Input Parameters:
4424 +  ts - the TS context
4425 .  A,B - Jacobian matrices
4426 .  func - function evaluation routine
4427 -  ctx - user context
4428 
4429    Calling sequence of func:
4430 $    flag = func (TS ts,PetscReal time,Vec u,Vec udot,Mat A,Mat B,void *ctx);
4431 
4432 
4433    Level: developer
4434 
4435 .keywords: TS, nonlinear, set, function
4436 
4437 .seealso: TSGetFunction(), TSComputeFunction(), TSSetJacobian(), TSSetFunction()
4438 */
4439 PetscErrorCode  TSSetJacobianMatlab(TS ts,Mat A,Mat B,const char *func,mxArray *ctx)
4440 {
4441   PetscErrorCode  ierr;
4442   TSMatlabContext *sctx;
4443 
4444   PetscFunctionBegin;
4445   /* currently sctx is memory bleed */
4446   ierr = PetscMalloc(sizeof(TSMatlabContext),&sctx);CHKERRQ(ierr);
4447   ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr);
4448   /*
4449      This should work, but it doesn't
4450   sctx->ctx = ctx;
4451   mexMakeArrayPersistent(sctx->ctx);
4452   */
4453   sctx->ctx = mxDuplicateArray(ctx);
4454 
4455   ierr = TSSetIJacobian(ts,A,B,TSComputeJacobian_Matlab,sctx);CHKERRQ(ierr);
4456   PetscFunctionReturn(0);
4457 }
4458 
4459 #undef __FUNCT__
4460 #define __FUNCT__ "TSMonitor_Matlab"
4461 /*
4462    TSMonitor_Matlab - Calls the function that has been set with TSMonitorSetMatlab().
4463 
4464    Collective on TS
4465 
4466 .seealso: TSSetFunction(), TSGetFunction()
4467 @*/
4468 PetscErrorCode  TSMonitor_Matlab(TS ts,PetscInt it, PetscReal time,Vec u, void *ctx)
4469 {
4470   PetscErrorCode  ierr;
4471   TSMatlabContext *sctx = (TSMatlabContext*)ctx;
4472   int             nlhs  = 1,nrhs = 6;
4473   mxArray         *plhs[1],*prhs[6];
4474   long long int   lx = 0,ls = 0;
4475 
4476   PetscFunctionBegin;
4477   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4478   PetscValidHeaderSpecific(u,VEC_CLASSID,4);
4479 
4480   ierr = PetscMemcpy(&ls,&ts,sizeof(ts));CHKERRQ(ierr);
4481   ierr = PetscMemcpy(&lx,&u,sizeof(u));CHKERRQ(ierr);
4482 
4483   prhs[0] =  mxCreateDoubleScalar((double)ls);
4484   prhs[1] =  mxCreateDoubleScalar((double)it);
4485   prhs[2] =  mxCreateDoubleScalar((double)time);
4486   prhs[3] =  mxCreateDoubleScalar((double)lx);
4487   prhs[4] =  mxCreateString(sctx->funcname);
4488   prhs[5] =  sctx->ctx;
4489   ierr    =  mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscTSMonitorInternal");CHKERRQ(ierr);
4490   ierr    =  mxGetScalar(plhs[0]);CHKERRQ(ierr);
4491   mxDestroyArray(prhs[0]);
4492   mxDestroyArray(prhs[1]);
4493   mxDestroyArray(prhs[2]);
4494   mxDestroyArray(prhs[3]);
4495   mxDestroyArray(prhs[4]);
4496   mxDestroyArray(plhs[0]);
4497   PetscFunctionReturn(0);
4498 }
4499 
4500 
4501 #undef __FUNCT__
4502 #define __FUNCT__ "TSMonitorSetMatlab"
4503 /*
4504    TSMonitorSetMatlab - Sets the monitor function from Matlab
4505 
4506    Level: developer
4507 
4508 .keywords: TS, nonlinear, set, function
4509 
4510 .seealso: TSGetFunction(), TSComputeFunction(), TSSetJacobian(), TSSetFunction()
4511 */
4512 PetscErrorCode  TSMonitorSetMatlab(TS ts,const char *func,mxArray *ctx)
4513 {
4514   PetscErrorCode  ierr;
4515   TSMatlabContext *sctx;
4516 
4517   PetscFunctionBegin;
4518   /* currently sctx is memory bleed */
4519   ierr = PetscMalloc(sizeof(TSMatlabContext),&sctx);CHKERRQ(ierr);
4520   ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr);
4521   /*
4522      This should work, but it doesn't
4523   sctx->ctx = ctx;
4524   mexMakeArrayPersistent(sctx->ctx);
4525   */
4526   sctx->ctx = mxDuplicateArray(ctx);
4527 
4528   ierr = TSMonitorSet(ts,TSMonitor_Matlab,sctx,NULL);CHKERRQ(ierr);
4529   PetscFunctionReturn(0);
4530 }
4531 #endif
4532 
4533 
4534 
4535 #undef __FUNCT__
4536 #define __FUNCT__ "TSMonitorLGSolution"
4537 /*@C
4538    TSMonitorLGSolution - Monitors progress of the TS solvers by plotting each component of the solution vector
4539        in a time based line graph
4540 
4541    Collective on TS
4542 
4543    Input Parameters:
4544 +  ts - the TS context
4545 .  step - current time-step
4546 .  ptime - current time
4547 -  lg - a line graph object
4548 
4549    Level: intermediate
4550 
4551     Notes: each process in a parallel run displays its component solutions in a separate window
4552 
4553 .keywords: TS,  vector, monitor, view
4554 
4555 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView()
4556 @*/
4557 PetscErrorCode  TSMonitorLGSolution(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
4558 {
4559   PetscErrorCode    ierr;
4560   TSMonitorLGCtx    ctx = (TSMonitorLGCtx)dummy;
4561   const PetscScalar *yy;
4562   PetscInt          dim;
4563 
4564   PetscFunctionBegin;
4565   if (!step) {
4566     PetscDrawAxis axis;
4567     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
4568     ierr = PetscDrawAxisSetLabels(axis,"Solution as function of time","Time","Solution");CHKERRQ(ierr);
4569     ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
4570     ierr = PetscDrawLGSetDimension(ctx->lg,dim);CHKERRQ(ierr);
4571     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
4572   }
4573   ierr = VecGetArrayRead(u,&yy);CHKERRQ(ierr);
4574 #if defined(PETSC_USE_COMPLEX)
4575   {
4576     PetscReal *yreal;
4577     PetscInt  i,n;
4578     ierr = VecGetLocalSize(u,&n);CHKERRQ(ierr);
4579     ierr = PetscMalloc(n*sizeof(PetscReal),&yreal);CHKERRQ(ierr);
4580     for (i=0; i<n; i++) yreal[i] = PetscRealPart(yy[i]);
4581     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yreal);CHKERRQ(ierr);
4582     ierr = PetscFree(yreal);CHKERRQ(ierr);
4583   }
4584 #else
4585   ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yy);CHKERRQ(ierr);
4586 #endif
4587   ierr = VecRestoreArrayRead(u,&yy);CHKERRQ(ierr);
4588   if (((ctx->howoften > 0) && (!(step % ctx->howoften)) && (step > -1)) || ((ctx->howoften == -1) && (step == -1))) {
4589     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
4590   }
4591   PetscFunctionReturn(0);
4592 }
4593 
4594 #undef __FUNCT__
4595 #define __FUNCT__ "TSMonitorLGError"
4596 /*@C
4597    TSMonitorLGError - Monitors progress of the TS solvers by plotting each component of the solution vector
4598        in a time based line graph
4599 
4600    Collective on TS
4601 
4602    Input Parameters:
4603 +  ts - the TS context
4604 .  step - current time-step
4605 .  ptime - current time
4606 -  lg - a line graph object
4607 
4608    Level: intermediate
4609 
4610    Notes:
4611    Only for sequential solves.
4612 
4613    The user must provide the solution using TSSetSolutionFunction() to use this monitor.
4614 
4615    Options Database Keys:
4616 .  -ts_monitor_lg_error - create a graphical monitor of error history
4617 
4618 .keywords: TS,  vector, monitor, view
4619 
4620 .seealso: TSMonitorSet(), TSMonitorDefault(), VecView(), TSSetSolutionFunction()
4621 @*/
4622 PetscErrorCode  TSMonitorLGError(TS ts,PetscInt step,PetscReal ptime,Vec u,void *dummy)
4623 {
4624   PetscErrorCode    ierr;
4625   TSMonitorLGCtx    ctx = (TSMonitorLGCtx)dummy;
4626   const PetscScalar *yy;
4627   Vec               y;
4628   PetscInt          dim;
4629 
4630   PetscFunctionBegin;
4631   if (!step) {
4632     PetscDrawAxis axis;
4633     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
4634     ierr = PetscDrawAxisSetLabels(axis,"Error in solution as function of time","Time","Solution");CHKERRQ(ierr);
4635     ierr = VecGetLocalSize(u,&dim);CHKERRQ(ierr);
4636     ierr = PetscDrawLGSetDimension(ctx->lg,dim);CHKERRQ(ierr);
4637     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
4638   }
4639   ierr = VecDuplicate(u,&y);CHKERRQ(ierr);
4640   ierr = TSComputeSolutionFunction(ts,ptime,y);CHKERRQ(ierr);
4641   ierr = VecAXPY(y,-1.0,u);CHKERRQ(ierr);
4642   ierr = VecGetArrayRead(y,&yy);CHKERRQ(ierr);
4643 #if defined(PETSC_USE_COMPLEX)
4644   {
4645     PetscReal *yreal;
4646     PetscInt  i,n;
4647     ierr = VecGetLocalSize(y,&n);CHKERRQ(ierr);
4648     ierr = PetscMalloc(n*sizeof(PetscReal),&yreal);CHKERRQ(ierr);
4649     for (i=0; i<n; i++) yreal[i] = PetscRealPart(yy[i]);
4650     ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yreal);CHKERRQ(ierr);
4651     ierr = PetscFree(yreal);CHKERRQ(ierr);
4652   }
4653 #else
4654   ierr = PetscDrawLGAddCommonPoint(ctx->lg,ptime,yy);CHKERRQ(ierr);
4655 #endif
4656   ierr = VecRestoreArrayRead(y,&yy);CHKERRQ(ierr);
4657   ierr = VecDestroy(&y);CHKERRQ(ierr);
4658   if (((ctx->howoften > 0) && (!(step % ctx->howoften)) && (step > -1)) || ((ctx->howoften == -1) && (step == -1))) {
4659     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
4660   }
4661   PetscFunctionReturn(0);
4662 }
4663 
4664 #undef __FUNCT__
4665 #define __FUNCT__ "TSMonitorLGSNESIterations"
4666 PetscErrorCode TSMonitorLGSNESIterations(TS ts,PetscInt n,PetscReal ptime,Vec v,void *monctx)
4667 {
4668   TSMonitorLGCtx ctx = (TSMonitorLGCtx) monctx;
4669   PetscReal      x   = ptime,y;
4670   PetscErrorCode ierr;
4671   PetscInt       its;
4672 
4673   PetscFunctionBegin;
4674   if (!n) {
4675     PetscDrawAxis axis;
4676 
4677     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
4678     ierr = PetscDrawAxisSetLabels(axis,"Nonlinear iterations as function of time","Time","SNES Iterations");CHKERRQ(ierr);
4679     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
4680 
4681     ctx->snes_its = 0;
4682   }
4683   ierr = TSGetSNESIterations(ts,&its);CHKERRQ(ierr);
4684   y    = its - ctx->snes_its;
4685   ierr = PetscDrawLGAddPoint(ctx->lg,&x,&y);CHKERRQ(ierr);
4686   if (((ctx->howoften > 0) && (!(n % ctx->howoften)) && (n > -1)) || ((ctx->howoften == -1) && (n == -1))) {
4687     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
4688   }
4689   ctx->snes_its = its;
4690   PetscFunctionReturn(0);
4691 }
4692 
4693 #undef __FUNCT__
4694 #define __FUNCT__ "TSMonitorLGKSPIterations"
4695 PetscErrorCode TSMonitorLGKSPIterations(TS ts,PetscInt n,PetscReal ptime,Vec v,void *monctx)
4696 {
4697   TSMonitorLGCtx ctx = (TSMonitorLGCtx) monctx;
4698   PetscReal      x   = ptime,y;
4699   PetscErrorCode ierr;
4700   PetscInt       its;
4701 
4702   PetscFunctionBegin;
4703   if (!n) {
4704     PetscDrawAxis axis;
4705 
4706     ierr = PetscDrawLGGetAxis(ctx->lg,&axis);CHKERRQ(ierr);
4707     ierr = PetscDrawAxisSetLabels(axis,"Linear iterations as function of time","Time","KSP Iterations");CHKERRQ(ierr);
4708     ierr = PetscDrawLGReset(ctx->lg);CHKERRQ(ierr);
4709 
4710     ctx->ksp_its = 0;
4711   }
4712   ierr = TSGetKSPIterations(ts,&its);CHKERRQ(ierr);
4713   y    = its - ctx->ksp_its;
4714   ierr = PetscDrawLGAddPoint(ctx->lg,&x,&y);CHKERRQ(ierr);
4715   if (((ctx->howoften > 0) && (!(n % ctx->howoften)) && (n > -1)) || ((ctx->howoften == -1) && (n == -1))) {
4716     ierr = PetscDrawLGDraw(ctx->lg);CHKERRQ(ierr);
4717   }
4718   ctx->ksp_its = its;
4719   PetscFunctionReturn(0);
4720 }
4721 
4722 #undef __FUNCT__
4723 #define __FUNCT__ "TSComputeLinearStability"
4724 /*@
4725    TSComputeLinearStability - computes the linear stability function at a point
4726 
4727    Collective on TS and Vec
4728 
4729    Input Parameters:
4730 +  ts - the TS context
4731 -  xr,xi - real and imaginary part of input arguments
4732 
4733    Output Parameters:
4734 .  yr,yi - real and imaginary part of function value
4735 
4736    Level: developer
4737 
4738 .keywords: TS, compute
4739 
4740 .seealso: TSSetRHSFunction(), TSComputeIFunction()
4741 @*/
4742 PetscErrorCode TSComputeLinearStability(TS ts,PetscReal xr,PetscReal xi,PetscReal *yr,PetscReal *yi)
4743 {
4744   PetscErrorCode ierr;
4745 
4746   PetscFunctionBegin;
4747   PetscValidHeaderSpecific(ts,TS_CLASSID,1);
4748   if (!ts->ops->linearstability) SETERRQ(PetscObjectComm((PetscObject)ts),PETSC_ERR_SUP,"Linearized stability function not provided for this method");
4749   ierr = (*ts->ops->linearstability)(ts,xr,xi,yr,yi);CHKERRQ(ierr);
4750   PetscFunctionReturn(0);
4751 }
4752