Actual source code: gladapt.c

petsc-3.4.4 2014-03-13
  2: #include <../src/ts/impls/implicit/gl/gl.h> /*I  "petscts.h" I*/

  4: static PetscFunctionList TSGLAdaptList;
  5: static PetscBool         TSGLAdaptPackageInitialized;
  6: static PetscBool         TSGLAdaptRegisterAllCalled;
  7: static PetscClassId      TSGLADAPT_CLASSID;

  9: struct _TSGLAdaptOps {
 10:   PetscErrorCode (*choose)(TSGLAdapt,PetscInt,const PetscInt[],const PetscReal[],const PetscReal[],PetscInt,PetscReal,PetscReal,PetscInt*,PetscReal*,PetscBool*);
 11:   PetscErrorCode (*destroy)(TSGLAdapt);
 12:   PetscErrorCode (*view)(TSGLAdapt,PetscViewer);
 13:   PetscErrorCode (*setfromoptions)(TSGLAdapt);
 14: };

 16: struct _p_TSGLAdapt {
 17:   PETSCHEADER(struct _TSGLAdaptOps);
 18:   void *data;
 19: };

 21: PETSC_EXTERN PetscErrorCode TSGLAdaptCreate_None(TSGLAdapt);
 22: PETSC_EXTERN PetscErrorCode TSGLAdaptCreate_Size(TSGLAdapt);
 23: PETSC_EXTERN PetscErrorCode TSGLAdaptCreate_Both(TSGLAdapt);

 27: /*@C
 28:    TSGLAdaptRegister -  adds a TSGLAdapt implementation

 30:    Not Collective

 32:    Input Parameters:
 33: +  name_scheme - name of user-defined adaptivity scheme
 34: -  routine_create - routine to create method context

 36:    Notes:
 37:    TSGLAdaptRegister() may be called multiple times to add several user-defined families.

 39:    Sample usage:
 40: .vb
 41:    TSGLAdaptRegister("my_scheme",MySchemeCreate);
 42: .ve

 44:    Then, your scheme can be chosen with the procedural interface via
 45: $     TSGLAdaptSetType(ts,"my_scheme")
 46:    or at runtime via the option
 47: $     -ts_adapt_type my_scheme

 49:    Level: advanced

 51: .keywords: TSGLAdapt, register

 53: .seealso: TSGLAdaptRegisterAll()
 54: @*/
 55: PetscErrorCode  TSGLAdaptRegister(const char sname[],PetscErrorCode (*function)(TSGLAdapt))
 56: {

 60:   PetscFunctionListAdd(&TSGLAdaptList,sname,function);
 61:   return(0);
 62: }

 66: /*@C
 67:   TSGLAdaptRegisterAll - Registers all of the adaptivity schemes in TSGLAdapt

 69:   Not Collective

 71:   Level: advanced

 73: .keywords: TSGLAdapt, register, all

 75: .seealso: TSGLAdaptRegisterDestroy()
 76: @*/
 77: PetscErrorCode  TSGLAdaptRegisterAll(void)
 78: {

 82:   TSGLAdaptRegister(TSGLADAPT_NONE,TSGLAdaptCreate_None);
 83:   TSGLAdaptRegister(TSGLADAPT_SIZE,TSGLAdaptCreate_Size);
 84:   TSGLAdaptRegister(TSGLADAPT_BOTH,TSGLAdaptCreate_Both);
 85:   return(0);
 86: }

 90: /*@C
 91:   TSGLFinalizePackage - This function destroys everything in the TSGL package. It is
 92:   called from PetscFinalize().

 94:   Level: developer

 96: .keywords: Petsc, destroy, package
 97: .seealso: PetscFinalize()
 98: @*/
 99: PetscErrorCode  TSGLAdaptFinalizePackage(void)
100: {

104:   PetscFunctionListDestroy(&TSGLAdaptList);
105:   TSGLAdaptPackageInitialized = PETSC_FALSE;
106:   TSGLAdaptRegisterAllCalled  = PETSC_FALSE;
107:   return(0);
108: }

112: /*@C
113:   TSGLAdaptInitializePackage - This function initializes everything in the TSGLAdapt package. It is
114:   called from PetscDLLibraryRegister() when using dynamic libraries, and on the first call to
115:   TSCreate_GL() when using static libraries.

117:   Level: developer

119: .keywords: TSGLAdapt, initialize, package
120: .seealso: PetscInitialize()
121: @*/
122: PetscErrorCode  TSGLAdaptInitializePackage(void)
123: {

127:   if (TSGLAdaptPackageInitialized) return(0);
128:   TSGLAdaptPackageInitialized = PETSC_TRUE;
129:   PetscClassIdRegister("TSGLAdapt",&TSGLADAPT_CLASSID);
130:   TSGLAdaptRegisterAll();
131:   PetscRegisterFinalize(TSGLAdaptFinalizePackage);
132:   return(0);
133: }

137: PetscErrorCode  TSGLAdaptSetType(TSGLAdapt adapt,TSGLAdaptType type)
138: {
139:   PetscErrorCode ierr,(*r)(TSGLAdapt);

142:   PetscFunctionListFind(TSGLAdaptList,type,&r);
143:   if (!r) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_UNKNOWN_TYPE,"Unknown TSGLAdapt type \"%s\" given",type);
144:   if (((PetscObject)adapt)->type_name) {(*adapt->ops->destroy)(adapt);}
145:   (*r)(adapt);
146:   PetscObjectChangeTypeName((PetscObject)adapt,type);
147:   return(0);
148: }

152: PetscErrorCode  TSGLAdaptSetOptionsPrefix(TSGLAdapt adapt,const char prefix[])
153: {

157:   PetscObjectSetOptionsPrefix((PetscObject)adapt,prefix);
158:   return(0);
159: }

163: PetscErrorCode  TSGLAdaptView(TSGLAdapt adapt,PetscViewer viewer)
164: {
166:   PetscBool      iascii;

169:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
170:   if (iascii) {
171:     PetscObjectPrintClassNamePrefixType((PetscObject)adapt,viewer,"TSGLAdapt Object");
172:     if (adapt->ops->view) {
173:       PetscViewerASCIIPushTab(viewer);
174:       (*adapt->ops->view)(adapt,viewer);
175:       PetscViewerASCIIPopTab(viewer);
176:     }
177:   }
178:   return(0);
179: }

183: PetscErrorCode  TSGLAdaptDestroy(TSGLAdapt *adapt)
184: {

188:   if (!*adapt) return(0);
190:   if (--((PetscObject)(*adapt))->refct > 0) {*adapt = 0; return(0);}
191:   if ((*adapt)->ops->destroy) {(*(*adapt)->ops->destroy)(*adapt);}
192:   PetscHeaderDestroy(adapt);
193:   return(0);
194: }

198: PetscErrorCode  TSGLAdaptSetFromOptions(TSGLAdapt adapt)
199: {
201:   char           type[256] = TSGLADAPT_BOTH;
202:   PetscBool      flg;

205:   /* This should use PetscOptionsBegin() if/when this becomes an object used outside of TSGL, but currently this
206:   * function can only be called from inside TSSetFromOptions_GL()  */
207:   PetscOptionsHead("TSGL Adaptivity options");
208:   PetscOptionsList("-ts_adapt_type","Algorithm to use for adaptivity","TSGLAdaptSetType",TSGLAdaptList,
209:                           ((PetscObject)adapt)->type_name ? ((PetscObject)adapt)->type_name : type,type,sizeof(type),&flg);
210:   if (flg || !((PetscObject)adapt)->type_name) {
211:     TSGLAdaptSetType(adapt,type);
212:   }
213:   if (adapt->ops->setfromoptions) {(*adapt->ops->setfromoptions)(adapt);}
214:   PetscOptionsTail();
215:   return(0);
216: }

220: PetscErrorCode  TSGLAdaptChoose(TSGLAdapt adapt,PetscInt n,const PetscInt orders[],const PetscReal errors[],const PetscReal cost[],PetscInt cur,PetscReal h,PetscReal tleft,PetscInt *next_sc,PetscReal *next_h,PetscBool  *finish)
221: {

232:   (*adapt->ops->choose)(adapt,n,orders,errors,cost,cur,h,tleft,next_sc,next_h,finish);
233:   return(0);
234: }

238: PetscErrorCode  TSGLAdaptCreate(MPI_Comm comm,TSGLAdapt *inadapt)
239: {
241:   TSGLAdapt      adapt;

244:   *inadapt = 0;
245:   PetscHeaderCreate(adapt,_p_TSGLAdapt,struct _TSGLAdaptOps,TSGLADAPT_CLASSID,"TSGLAdapt","General Linear adaptivity","TS",comm,TSGLAdaptDestroy,TSGLAdaptView);
246:   *inadapt = adapt;
247:   return(0);
248: }


251: /*
252: *  Implementations
253: */

257: static PetscErrorCode TSGLAdaptDestroy_JustFree(TSGLAdapt adapt)
258: {

262:   PetscFree(adapt->data);
263:   return(0);
264: }

266: /* -------------------------------- None ----------------------------------- */
267: typedef struct {
268:   PetscInt  scheme;
269:   PetscReal h;
270: } TSGLAdapt_None;

274: static PetscErrorCode TSGLAdaptChoose_None(TSGLAdapt adapt,PetscInt n,const PetscInt orders[],const PetscReal errors[],const PetscReal cost[],PetscInt cur,PetscReal h,PetscReal tleft,PetscInt *next_sc,PetscReal *next_h,PetscBool  *finish)
275: {

278:   *next_sc = cur;
279:   *next_h  = h;
280:   if (*next_h > tleft) {
281:     *finish = PETSC_TRUE;
282:     *next_h = tleft;
283:   } else *finish = PETSC_FALSE;
284:   return(0);
285: }

289: PetscErrorCode  TSGLAdaptCreate_None(TSGLAdapt adapt)
290: {
292:   TSGLAdapt_None *a;

295:   PetscNewLog(adapt,TSGLAdapt_None,&a);
296:   adapt->data         = (void*)a;
297:   adapt->ops->choose  = TSGLAdaptChoose_None;
298:   adapt->ops->destroy = TSGLAdaptDestroy_JustFree;
299:   return(0);
300: }

302: /* -------------------------------- Size ----------------------------------- */
303: typedef struct {
304:   PetscReal desired_h;
305: } TSGLAdapt_Size;


310: static PetscErrorCode TSGLAdaptChoose_Size(TSGLAdapt adapt,PetscInt n,const PetscInt orders[],const PetscReal errors[],const PetscReal cost[],PetscInt cur,PetscReal h,PetscReal tleft,PetscInt *next_sc,PetscReal *next_h,PetscBool  *finish)
311: {
312:   TSGLAdapt_Size *sz = (TSGLAdapt_Size*)adapt->data;
313:   PetscReal      dec = 0.2,inc = 5.0,safe = 0.9,optimal,last_desired_h;

316:   *next_sc = cur;
317:   optimal  = PetscPowReal((PetscReal)errors[cur],(PetscReal)-1./(safe*orders[cur]));
318:   /* Step sizes oscillate when there is no smoothing.  Here we use a geometric mean of the the current step size and the
319:   * one that would have been taken (without smoothing) on the last step. */
320:   last_desired_h = sz->desired_h;
321:   sz->desired_h  = h*PetscMax(dec,PetscMin(inc,optimal)); /* Trim to [dec,inc] */

323:   /* Normally only happens on the first step */
324:   if (last_desired_h > 1e-14) *next_h = PetscSqrtReal(last_desired_h * sz->desired_h);
325:   else *next_h = sz->desired_h;

327:   if (*next_h > tleft) {
328:     *finish = PETSC_TRUE;
329:     *next_h = tleft;
330:   } else *finish = PETSC_FALSE;
331:   return(0);
332: }

336: PetscErrorCode  TSGLAdaptCreate_Size(TSGLAdapt adapt)
337: {
339:   TSGLAdapt_Size *a;

342:   PetscNewLog(adapt,TSGLAdapt_Size,&a);
343:   adapt->data         = (void*)a;
344:   adapt->ops->choose  = TSGLAdaptChoose_Size;
345:   adapt->ops->destroy = TSGLAdaptDestroy_JustFree;
346:   return(0);
347: }

349: /* -------------------------------- Both ----------------------------------- */
350: typedef struct {
351:   PetscInt  count_at_order;
352:   PetscReal desired_h;
353: } TSGLAdapt_Both;


358: static PetscErrorCode TSGLAdaptChoose_Both(TSGLAdapt adapt,PetscInt n,const PetscInt orders[],const PetscReal errors[],const PetscReal cost[],PetscInt cur,PetscReal h,PetscReal tleft,PetscInt *next_sc,PetscReal *next_h,PetscBool  *finish)
359: {
360:   TSGLAdapt_Both *both = (TSGLAdapt_Both*)adapt->data;
362:   PetscReal      dec = 0.2,inc = 5.0,safe = 0.9;
363:   struct {PetscInt id; PetscReal h,eff;} best={-1,0,0},trial={-1,0,0},current={-1,0,0};
364:   PetscInt i;

367:   for (i=0; i<n; i++) {
368:     PetscReal optimal;
369:     trial.id  = i;
370:     optimal   = PetscPowReal((PetscReal)errors[i],(PetscReal)-1./(safe*orders[i]));
371:     trial.h   = h*optimal;
372:     trial.eff = trial.h/cost[i];
373:     if (trial.eff > best.eff) {PetscMemcpy(&best,&trial,sizeof(trial));}
374:     if (i == cur) {PetscMemcpy(&current,&trial,sizeof(trial));}
375:   }
376:   /* Only switch orders if the scheme offers significant benefits over the current one.
377:   When the scheme is not changing, only change step size if it offers significant benefits. */
378:   if (best.eff < 1.2*current.eff || both->count_at_order < orders[cur]+2) {
379:     PetscReal last_desired_h;
380:     *next_sc        = current.id;
381:     last_desired_h  = both->desired_h;
382:     both->desired_h = PetscMax(h*dec,PetscMin(h*inc,current.h));
383:     *next_h         = (both->count_at_order > 0)
384:                       ? PetscSqrtReal(last_desired_h * both->desired_h)
385:                       : both->desired_h;
386:     both->count_at_order++;
387:   } else {
388:     PetscReal rat = cost[best.id]/cost[cur];
389:     *next_sc = best.id;
390:     *next_h  = PetscMax(h*rat*dec,PetscMin(h*rat*inc,best.h));
391:     both->count_at_order = 0;
392:     both->desired_h      = best.h;
393:   }

395:   if (*next_h > tleft) {
396:     *finish = PETSC_TRUE;
397:     *next_h = tleft;
398:   } else *finish = PETSC_FALSE;
399:   return(0);
400: }

404: PetscErrorCode TSGLAdaptCreate_Both(TSGLAdapt adapt)
405: {
407:   TSGLAdapt_Both *a;

410:   PetscNewLog(adapt,TSGLAdapt_Both,&a);
411:   adapt->data         = (void*)a;
412:   adapt->ops->choose  = TSGLAdaptChoose_Both;
413:   adapt->ops->destroy = TSGLAdaptDestroy_JustFree;
414:   return(0);
415: }