Actual source code: combustion3.c

  1: /*$Id: combustion.c,v 1.1 2002/08/08 9:39 lopezca@mauddib.mcs.anl.gov $*/

  3: /* Program usage: mpirun -np <proc> combustion [-help] [all TAO options] */

  5: /*
  6:   Include "tao.h" so we can use TAO solvers.
  7:   petscda.h for distributed array
  8:   ad_deriv.h for AD gradient
  9: */

 11: #include "petscda.h"
 12: #include "tao.h"
 13: #include "taodaapplication.h"

 15: static char help[] = "Steady-State Combustion.\n\
 16: We solve the Steady-State Combustion problem (MINPACK-2 test suite) in a 2D\n\
 17: rectangular domain, using distributed arrays (DAs) to partition the parallel grid.\n\
 18: The command line options include:\n\
 19:   -mx <xg>, where <xg> = number of grid points in the 1st coordinate direction\n\
 20:   -my <yg>, where <yg> = number of grid points in the 2nd coordinate direction\n\
 21:   -nlevels <nlevels>, where <nlevels> = number of levels in multigrid\n\
 22:   -byelement, if computation is made by functions on rectangular elements\n\
 23:   -adic, if AD is used (AD is not used by default)\n\
 24:   -par <parameter>, where <parameter> indicates the problem's nonlinearity\n\
 25:      parameter lambda (0 <= par <= 6.81)\n\n";

 27: /*T
 28:    Concepts: TAO - Solving a bounded minimization problem
 29:    Routines: TaoInitialize(); TaoFinalize();
 30:    Routines: TaoCreate(); TaoDestroy();
 31:    Routines: DAApplicationCreate(); DAApplicationDestroy();
 32:    Routines: DAAppSetVariableBoundsRoutine();
 33:    Routines: DAAppSetElementObjectiveAndGradientRoutine();
 34:    Routines: DAAppSetElementHessianRoutine();
 35:    Routines: DAAppSetObjectiveAndGradientRoutine();
 36:    Routines: DAAppSetADElementFunctionGradient();
 37:    Routines: DAAppSetHessianRoutine();
 38:    Routines: TaoAppSetOptions();
 39:    Routines: TaoGetSolutionStatus(); TaoDAAppSolve();
 40:    Routines: DAAppSetMonitor(); TaoView();
 41:    Routines: DAAppGetSolution();
 42:    Routines: DAAppGetInterpolationMatrix();
 43:    Processors: n
 44: T*/

 46: /*
 47:    User-defined application context - contains data needed by the
 48:    application-provided call-back routines.
 49: */

 51: typedef struct {
 52:   InactiveDouble      param;
 53:   InactiveDouble      hx, hy;        /* increment size in both directions */
 54:   InactiveDouble      area;          /* area of the triangles */
 55: } ADFGCtx;

 57: typedef struct {
 58:   PetscReal  param;          /* nonlinearity parameter */
 59:   double  hx, hy, area;   /* increments and area of the triangle */
 60:   int     mx, my;         /* discretization including boundaries */
 61:   ADFGCtx fgctx;          /* Used only when an ADIC generated gradient is used */
 62: } AppCtx;
 63: int ad_CombLocalFunction(int[2], DERIV_TYPE[4], DERIV_TYPE*, void*);

 65: /* User-defined routines foun in this file */
 66: static int AppCtxInitialize(void *ptr);
 67: static int FormInitialGuess(DA, Vec, AppCtx*);

 69: static int CombLocalFunctionGradient(int[3], double x[4], double *f, double g[4], void *ptr);
 70: static int WholeCombFunctionGradient(TAO_APPLICATION,DA,Vec,double *,Vec,void*);

 72: static int CombLocalHessian(int[3], double x[4], double H[4][4], void *ptr);
 73: static int WholeCombHessian(TAO_APPLICATION,DA,Vec,Mat,void*);

 75: static int DAFixBoundary(TAO_APPLICATION, DA, Vec, Vec, void*);

 77: static int MyGridMonitorBefore(TAO_APPLICATION, DA, int, void *);


 82: int main( int argc, char **argv ) {

 84:   int             info,iter;           /* used to check for functions returning nonzeros */
 85:   int             Nx,Ny;
 86:   int             nlevels;                                           /* multigrid levels */
 87:   double          ff,gnorm;
 88:   DA              DAarray[20];
 89:   Vec             X;
 90:   KSP             ksp;
 91:   PetscTruth      flg, PreLoad = PETSC_TRUE;                                    /* flags */
 92:   AppCtx          user;                                     /* user-defined work context */
 93:   TaoMethod       method = "tao_tron";                            /* minimization method */
 94:   TAO_SOLVER      tao;                                      /* TAO_SOLVER solver context */
 95:   TAO_APPLICATION CombApp;                                   /* The PETSc application */
 96:   TaoTerminateReason reason;

 98:   /* Initialize TAO */
 99:   PetscInitialize(&argc, &argv, (char *)0, help);
100:   TaoInitialize(&argc, &argv, (char *)0, help);

102:   PreLoadBegin(PreLoad,"Solve");
103:   
104:   info = AppCtxInitialize((void*)&user); CHKERRQ(info);

106:   nlevels=5;
107:   info = PetscOptionsGetInt(PETSC_NULL,"-nlevels",&nlevels,&flg); CHKERRQ(info);
108:   if (PreLoadIt == 0) {
109:     nlevels = 1; user.mx = 11; user.my = 11;}

111:   PetscPrintf(MPI_COMM_WORLD,"\n---- Steady-State Combustion Problem -----\n\n");

113:   /* Let PETSc determine the vector distribution */
114:   Nx = PETSC_DECIDE; Ny = PETSC_DECIDE;

116:   /* Create distributed array (DA) to manage parallel grid and vectors  */
117:   info = DACreate2d(PETSC_COMM_WORLD,DA_NONPERIODIC,DA_STENCIL_BOX,user.mx,
118:                     user.my,Nx,Ny,1,1,PETSC_NULL,PETSC_NULL,&DAarray[0]); CHKERRQ(info);
119:   for (iter=1;iter<nlevels;iter++){
120:     info = DARefine(DAarray[iter-1],PETSC_COMM_WORLD,&DAarray[iter]); CHKERRQ(info);
121:   }

123:   /* Create TAO solver and set desired solution method */
124:   info = TaoCreate(MPI_COMM_WORLD,method,&tao); CHKERRQ(info);

126:   info = TaoApplicationCreate(PETSC_COMM_WORLD, &CombApp); CHKERRQ(info);
127:   info = TaoAppSetDAApp(CombApp,DAarray,nlevels); CHKERRQ(info);

129:   /* Sets routines for function, gradient and bounds evaluation */
130:   info = DAAppSetVariableBoundsRoutine(CombApp,DAFixBoundary,(void *)&user); CHKERRQ(info);

132:   info = PetscOptionsHasName(TAO_NULL, "-byelement", &flg); CHKERRQ(info);
133:   if (flg) {

135:     /* Sets routines for function and gradient evaluation, element by element */
136:     info = PetscOptionsHasName(TAO_NULL, "-adic", &flg); CHKERRQ(info);
137:     if (flg) {
138:       info = DAAppSetADElementFunctionGradient(CombApp,ad_CombLocalFunction,228,(void *)&user.fgctx); CHKERRQ(info);
139:     } else {
140:       info = DAAppSetElementObjectiveAndGradientRoutine(CombApp,CombLocalFunctionGradient,51,(void *)&user); CHKERRQ(info);
141:     }
142:     /* Sets routines for Hessian evaluation, element by element */
143:     info = DAAppSetElementHessianRoutine(CombApp,CombLocalHessian,21,(void*)&user); CHKERRQ(info);

145:   } else {

147:     /* Sets routines for function and gradient evaluation, all in one routine */
148:     info = DAAppSetObjectiveAndGradientRoutine(CombApp,WholeCombFunctionGradient,(void *)&user); CHKERRQ(info);

150:     /* Sets routines for Hessian evaluation, all in one routine */
151:     info = DAAppSetHessianRoutine(CombApp,WholeCombHessian,(void*)&user); CHKERRQ(info);    
152:     
153:   }

155:   info = DAAppSetBeforeMonitor(CombApp,MyGridMonitorBefore,(void*)&user); CHKERRQ(info);
156:   info = DAAppPrintInterpolationError(CombApp); CHKERRQ(info);
157:   //  info = DAAppPrintStageTimes(CombApp); CHKERRQ(info);

159:   info = TaoAppSetRelativeTolerance(CombApp,1.0e-6); CHKERRQ(info);
160:   info = TaoSetTolerances(tao,0,0,0,0); CHKERRQ(info);
161:   info = TaoSetGradientTolerances(tao,0,0,0); CHKERRQ(info);

163:   info = TaoAppGetKSP(CombApp,&ksp);CHKERRQ(info);
164:   info = KSPSetType(ksp,KSPCG); CHKERRQ(info);
165:   info = KSPSetTolerances(ksp,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,100);CHKERRQ(info);

167:   /* Check for any tao command line options */
168:   info = TaoSetOptions(CombApp, tao); CHKERRQ(info);

170:   info = DAAppGetSolution(CombApp,0,&X); CHKERRQ(info);
171:   info = FormInitialGuess(DAarray[0],X,&user); CHKERRQ(info);
172:   info = DAAppSetInitialSolution(CombApp,X); CHKERRQ(info);

174:   /* SOLVE THE APPLICATION */
175:   info = TaoDAAppSolve(CombApp, tao);  CHKERRQ(info);

177:   /* Get information on termination */
178:   info = TaoGetSolutionStatus(tao,&iter,&ff,&gnorm,0,0,&reason); CHKERRQ(info);
179:   if (reason <= 0 ){
180:     PetscPrintf(MPI_COMM_WORLD,"Try a different TAO method, adjust some parameters, or check the function evaluation routines\n");
181:     PetscPrintf(MPI_COMM_WORLD," Iterations: %d,  Function Value: %4.2e, Residual: %4.2e \n",iter,ff,gnorm);
182:   }

184:   info = PetscOptionsHasName(PETSC_NULL,"-view_sol",&flg); CHKERRQ(info);
185:   if (flg){
186:     info = DAAppGetSolution(CombApp,nlevels-1,&X); CHKERRQ(info);
187:     info=VecView(X,PETSC_VIEWER_STDOUT_WORLD); CHKERRQ(info);
188:   }

190:   /*  To View TAO solver information */
191:   // info = TaoView(tao); CHKERRQ(info);

193:   /* Free TAO data structures */
194:   info = TaoDestroy(tao); CHKERRQ(info);
195:   info = TaoAppDestroy(CombApp); CHKERRQ(info);

197:   /* Free PETSc data structures */
198:   for (iter=0;iter<nlevels;iter++){
199:     info = DADestroy(DAarray[iter]); CHKERRQ(info);
200:   }

202:   PreLoadEnd();

204:   /* Finalize TAO */
205:   TaoFinalize();
206:   PetscFinalize();

208:   return 0;
209: } /* main */



213: /*----- The following two routines
214:    
215:   MyGridMonitorBefore    MyGridMonitorAfter

217:   help diplay info of iterations at every grid level -------*/

221: static int MyGridMonitorBefore(TAO_APPLICATION myapp, DA da, int level, void *ctx) {

223:   AppCtx *user = (AppCtx*)ctx;
224:   int info,mx,my;

226:   info = DAGetInfo(da,PETSC_NULL,&mx,&my,PETSC_NULL,PETSC_NULL,PETSC_NULL,PETSC_NULL,
227:                    PETSC_NULL,PETSC_NULL,PETSC_NULL,PETSC_NULL);CHKERRQ(info);
228:   user->mx = mx;
229:   user->my = my;
230:   user->hx = 1.0 / (user->mx - 1);
231:   user->hy = 1.0 / (user->my - 1);
232:   user->area = 0.5 * user->hx * user->hy;
233:   user->fgctx.hx   = user->hx;
234:   user->fgctx.hy   = user->hy;
235:   user->fgctx.area = user->area;
236:   user->fgctx.param = user->param;

238:   PetscPrintf(MPI_COMM_WORLD,"Grid: %d,    mx: %d     my: %d   \n",level,mx,my);
239:   return 0;
240: }

242: /*------- USER-DEFINED: initialize the application context information -------*/

246: /*
247:   AppCtxInitialize - Sets initial values for the application context parameters

249:   Input:
250:     ptr - void user-defined application context

252:   Output:
253:     ptr - user-defined application context with the default or user-provided
254:              parameters
255: */
256: static int AppCtxInitialize(void *ptr) {

258:   AppCtx *user = (AppCtx*)ptr;
259:   PetscReal     LambdaMax = 6.81, LambdaMin = 0.0;  /* bounds on parameter lambda */
260:   PetscTruth    flg;            /* flag for PETSc calls */
261:   int info;

263:   /* Specify dimension of the problem */
264:   user->param = 5.0;
265:   user->mx = 11;
266:   user->my = 11;

268:   /* Check for any command line arguments that override defaults */
269:   info = PetscOptionsGetReal(TAO_NULL, "-par", &user->param, &flg); CHKERRQ(info);
270:   if (user->param >= LambdaMax || user->param <= LambdaMin) {
271:     SETERRQ(1,"Lambda is out of range.");
272:   }
273:   info = PetscOptionsGetInt(PETSC_NULL,"-mx",&user->mx,&flg); CHKERRQ(info);
274:   info = PetscOptionsGetInt(PETSC_NULL,"-my",&user->my,&flg); CHKERRQ(info);

276:   user->hx = 1.0 / (user->mx - 1);
277:   user->hy = 1.0 / (user->my - 1);
278:   user->area = 0.5 * user->hx * user->hy;
279:   info = PetscLogFlops(6); CHKERRQ(info);

281:   return 0;
282: } /* AppCtxInitialize */



288: static int FormInitialGuess(DA da, Vec X, AppCtx *ctx)
289: {
290:   int    info, i, j, mx, my;
291:   int    xs, ys, xm, ym, xe, ye;
292:   PetscReal hx, hy, temp, val, lambda;
293:   double **x;

295:   lambda = ctx->param;
296:   lambda = lambda/(lambda+1.0);

298:   /* Get local mesh boundaries */
299:   info = DAGetInfo(da,PETSC_NULL,&mx,&my,PETSC_NULL,PETSC_NULL,PETSC_NULL,PETSC_NULL,
300:                    PETSC_NULL,PETSC_NULL,PETSC_NULL,PETSC_NULL);CHKERRQ(info);
301:   hx = 1.0/(mx-1);  hy = 1.0/(my-1);

303:   info = DAGetCorners(da,&xs,&ys,PETSC_NULL,&xm,&ym,PETSC_NULL); CHKERRQ(info);
304:   xe = xs+xm; ye = ys+ym;

306:   info = DAVecGetArray(da, X, (void**)&x); CHKERRQ(info);
307:   /* Compute initial guess over locally owned part of mesh */
308:   for (j=ys; j<ye; j++) {  /*  for (j=0; j<my; j++) */
309:     temp = PetscMin(j+1,my-j)*hy;
310:     for (i=xs; i<xe; i++) {  /*  for (i=0; i<mx; i++) */
311:       val = lambda*sqrt(PetscMin((PetscMin(i+1,mx-i))*hx,temp));
312:       x[j][i] = val;
313:     }
314:   }
315:   info = DAVecRestoreArray(da, X, (void**)&x); CHKERRQ(info);

317:   return 0;
318: }


321: /*------- USER-DEFINED: set the upper and lower bounds for the variables  -------*/

325: /*
326:   FormBounds - Forms bounds on the variables

328:   Input:
329:     user - user-defined application context

331:   Output:
332:     XL - vector of lower bounds
333:     XU - vector of upper bounds

335: */
336: static int DAFixBoundary(TAO_APPLICATION daapplication, DA da, Vec XL, Vec XU, void *ptr)
337: {
338:   AppCtx *user = (AppCtx*)ptr;
339:   int i, j, mx, my, info, xs, xm, ys, ym;
340:   double lb = -TAO_INFINITY;
341:   double ub = TAO_INFINITY;
342:   double **xl, **xu;

344:   mx = user->mx;  /* number of points including the boundary */
345:   my = user->my;

347:   info = DAVecGetArray(da, XL, (void**)&xl); CHKERRQ(info);
348:   info = DAVecGetArray(da, XU, (void**)&xu); CHKERRQ(info);
349:   info = DAGetCorners(da, &xs, &ys, TAO_NULL, &xm, &ym, TAO_NULL); CHKERRQ(info);

351:   /* Compute initial guess over locally owned part of the grid */
352:   for (j = ys; j < ys+ym; j++){
353:     for (i = xs; i < xs+xm; i++){
354:       if (i == 0 || j == 0 || i == mx - 1 || j == my - 1) {
355:         xl[j][i] = xu[j][i] = 0.0;
356:       } else {
357:         xl[j][i] = lb;
358:         xu[j][i] = ub;
359:       }
360:     }
361:   }

363:   info = DAVecRestoreArray(da, XL, (void**)&xl); CHKERRQ(info);
364:   info = DAVecRestoreArray(da, XU, (void**)&xu); CHKERRQ(info);

366:   return 0;
367: } /* DAFixBoundary */


370: /*------- USER-DEFINED: routine to evaluate the function and gradient
371:            at a local (rectangular element) level              -------*/

375: /*
376:   CombLocalFunctionGradient - Evaluates function and gradient over the 
377:       local rectangular element

379:   Input:
380:     coor - vector with the indices of the position of current element
381:              in the first, second and third directions
382:     x - current point (values over the current rectangular element)
383:     ptr - user-defined application context

385:   Output:
386:     f - value of the objective funtion at the local rectangular element
387:     g - gradient of the local function

389: */
390: static int CombLocalFunctionGradient(int coor[2], double x[4], double *f, double g[4], void *ptr) {

392:   AppCtx *user = (AppCtx*)ptr;

394:   double lambdad3, hx, hy, area;
395:   double fquad, fexp, dvdx, dvdy;

397:   lambdad3 = user->param / 3.0;
398:   hx = user->hx;
399:   hy = user->hy;
400:   area = user->area;

402:   /* lower triangle contribution */
403:   dvdx = (x[0] - x[1]) / hx;
404:   dvdy = (x[0] - x[2]) / hy;
405:   fquad = dvdx * dvdx + dvdy * dvdy;
406:   fexp = exp(x[0]) + exp(x[1]) + exp(x[2]);

408:   dvdx = 0.5 * dvdx * hy;
409:   dvdy = 0.5 * dvdy * hx;
410:   g[0] = dvdx + dvdy - exp(x[0]) * area * lambdad3;
411:   g[1] = -dvdx - 2.0 * exp(x[1]) * area * lambdad3;
412:   g[2] = -dvdy - 2.0 * exp(x[2]) * area * lambdad3;

414:   /* upper triangle contribution */
415:   dvdx = (x[3] - x[2]) / hx;
416:   dvdy = (x[3] - x[1]) / hy;
417:   fquad += dvdx * dvdx + dvdy * dvdy;
418:   fexp += exp(x[1]) + exp(x[2]) + exp(x[3]);

420:   dvdx = 0.5 * dvdx * hy;
421:   dvdy = 0.5 * dvdy * hx;
422:   g[1] += -dvdy;
423:   g[2] += -dvdx;
424:   g[3] = dvdx + dvdy - exp(x[3]) * area * lambdad3;


427:   *f = area * (0.5 * fquad - lambdad3 * fexp);

429:   return 0;
430: } /* CombLocalFunctionGradient */


433: /*------- USER-DEFINED: routine to evaluate the Hessian
434:            at a local (rectangular element) level       -------*/

438: /*
439:   CombLocalHessian - Computes the Hessian of the local (partial) function
440:          defined over the current rectangle

442:   Input:
443:     coor - vector with the indices of the position of current element
444:              in the first, second and third directions
445:     x - current local solution (over the rectangle only)
446:     ptr - user-defined application context

448:   Output:
449:     H - Hessian matrix of the local function (wrt the four
450:            points of the rectangle only)

452: */
453: static int CombLocalHessian(int coor[2], double x[4], double H[4][4],void *ptr) {

455:   AppCtx *user = (AppCtx*)ptr;
456:   double hx, hy, lambdad3, area, dxdy, dydx;
457:   double diagxy, dexp, bandxy, bandyx;

459:   hx = user->hx;
460:   hy = user->hy;
461:   lambdad3 = user->param / 3.0;
462:   area = user->area;
463:   dxdy = hx/hy;
464:   dydx = hy/hx;
465:   diagxy = 0.5 * (dxdy + dydx);
466:   bandxy = -0.5 * dxdy;
467:   bandyx = -0.5 * dydx;

469:           /* Hessian contribution at 0,0 */
470:   dexp = exp(x[0]) * area * lambdad3;
471:   H[0][0] = diagxy - dexp;
472:   H[0][1] = H[1][0] = bandyx;
473:   H[0][2] = H[2][0] = bandxy;
474:   H[0][3] = H[3][0] = 0.0;

476:           /* Hessian contribution at 1,0 */
477:   dexp = exp(x[1]) * area * 2.0 * lambdad3;
478:   H[1][1] = diagxy - dexp;
479:   H[1][2] = H[2][1] = 0.0;
480:   H[1][3] = H[3][1] = bandxy;

482:           /* Hessian contribution at 0,1 */
483:   dexp = exp(x[2]) * area * 2.0 * lambdad3;
484:   H[2][2] = diagxy - dexp;
485:   H[2][3] = H[3][2] = bandyx;

487:           /* Hessian contribution at 1,1 */
488:   dexp = exp(x[3]) * area * lambdad3;
489:   H[3][3] = diagxy - dexp;

491:   return 0;
492: } /* CombLocalHessian */


495: /*------- USER-DEFINED: routine to evaluate the function 
496:           and gradient at the whole grid             -------*/

500: /*
501:   WholeCombFunctionGradient - Evaluates function and gradient over the 
502:       whole grid

504:   Input:
505:     daapplication - TAO application object
506:     da  - distributed array
507:     X   - the current point, at which the function and gradient are evaluated
508:     ptr - user-defined application context

510:   Output:
511:     f - value of the objective funtion at X
512:     G - gradient at X
513: */
514: static int WholeCombFunctionGradient(TAO_APPLICATION daapplication, DA da, Vec X, double *f, Vec G, void *ptr) {

516:   AppCtx *user = (AppCtx*)ptr;
517:   Vec localX, localG;
518:   int info, i, j;
519:   int xs, xm, gxs, gxm, xe, ys, ym, gys, gym, ye;
520:   double **x, **g;
521:   double floc = 0.0;
522:   PetscScalar zero = 0.0;

524:   double lambdad3, hx, hy, area;
525:   double fquad, fexp, dvdx, dvdy;

527:   lambdad3 = user->param / 3.0;
528:   hx = user->hx;
529:   hy = user->hy;
530:   area = user->area;

532:   info = DAGetLocalVector(da, &localX); CHKERRQ(info);
533:   info = DAGetLocalVector(da, &localG); CHKERRQ(info);
534:   info = VecSet(G, zero); CHKERRQ(info);
535:   info = VecSet(localG, zero); CHKERRQ(info);

537:   info = DAGlobalToLocalBegin(da, X, INSERT_VALUES, localX); CHKERRQ(info);
538:   info = DAGlobalToLocalEnd(da, X, INSERT_VALUES, localX); CHKERRQ(info);

540:   info = DAVecGetArray(da, localX, (void**)&x); CHKERRQ(info);
541:   info = DAVecGetArray(da, localG, (void**)&g); CHKERRQ(info);

543:   info = DAGetCorners(da, &xs, &ys, TAO_NULL, &xm, &ym, TAO_NULL); CHKERRQ(info);
544:   info = DAGetGhostCorners(da, &gxs, &gys, TAO_NULL, &gxm, &gym, TAO_NULL); CHKERRQ(info);

546:   xe = gxs + gxm - 1;
547:   ye = gys + gym - 1;
548:   for (j = ys; j < ye; j++) {
549:     for (i = xs; i < xe; i++) {

551:       /* lower triangle contribution */
552:       dvdx = (x[j][i] - x[j][i+1]) / hx;  
553:       dvdy = (x[j][i] - x[j+1][i]) / hy;
554:       fquad = dvdx * dvdx + dvdy * dvdy;
555:       fexp = exp(x[j][i]) + exp(x[j][i+1]) + exp(x[j+1][i]);

557:       dvdx = 0.5 * dvdx * hy;
558:       dvdy = 0.5 * dvdy * hx;
559:       g[j][i] += dvdx + dvdy - exp(x[j][i]) * area * lambdad3;
560:       g[j][i+1] += -dvdx - 2.0 * exp(x[j][i+1]) * area * lambdad3;
561:       g[j+1][i] += -dvdy - 2.0 * exp(x[j+1][i]) * area * lambdad3;

563:       /* upper triangle contribution */
564:       dvdx = (x[j+1][i+1] - x[j+1][i]) / hx;
565:       dvdy = (x[j+1][i+1] - x[j][i+1]) / hy;
566:       fquad += dvdx * dvdx + dvdy * dvdy;
567:       fexp += exp(x[j][i+1]) + exp(x[j+1][i]) + exp(x[j+1][i+1]);

569:       dvdx = 0.5 * dvdx * hy;
570:       dvdy = 0.5 * dvdy * hx;
571:       g[j][i+1] += -dvdy;
572:       g[j+1][i] += -dvdx;
573:       g[j+1][i+1] += dvdx + dvdy - exp(x[j+1][i+1]) * area * lambdad3;

575:       floc += area * (0.5 * fquad - fexp * lambdad3);

577:     }
578:   }

580:   info = MPI_Allreduce(&floc, f, 1, MPI_DOUBLE, MPI_SUM, MPI_COMM_WORLD); CHKERRQ(info);

582:   info = DAVecRestoreArray(da, localX, (void**)&x); CHKERRQ(info);
583:   info = DAVecRestoreArray(da, localG, (void**)&g); CHKERRQ(info);

585:   info = DALocalToGlobalBegin(da, localG, G); CHKERRQ(info);
586:   info = DALocalToGlobalEnd(da, localG, G); CHKERRQ(info);

588:   info = DARestoreLocalVector(da, &localX); CHKERRQ(info);
589:   info = DARestoreLocalVector(da, &localG); CHKERRQ(info);

591:   info = PetscLogFlops((xe-xs) * (ye-ys) * 55 + 1); CHKERRQ(info);
592:   return 0;

594: } /* WholeCombFunctionGradient */


597: /*------- USER-DEFINED: routine to evaluate the Hessian 
598:           at the whole grid             -------*/
601: /*
602:   WholeCombHessian - Evaluates Hessian over the whole grid

604:   Input:
605:     daapplication - TAO application object
606:     da  - distributed array
607:     X   - the current point, at which the function and gradient are evaluated
608:     ptr - user-defined application context

610:   Output:
611:     H - Hessian at X
612: */
613: static int WholeCombHessian(TAO_APPLICATION daapplication, DA da, Vec X, Mat H, void *ptr) {

615:   AppCtx *user = (AppCtx*)ptr;
616:   Vec localX;
617:   int info, i, j, ind[4];
618:   int xs, xm, gxs, gxm, xe, ys, ym, gys, gym, ye;
619:   double smallH[4][4];
620:   double **x;

622:   double hx, hy, lambdad3, area, dxdy, dydx;
623:   double diagxy, dexp, bandxy, bandyx;
624:   PetscTruth assembled;


627:   hx = user->hx;
628:   hy = user->hy;
629:   lambdad3 = user->param / 3.0;
630:   area = user->area;
631:   dxdy = hx/hy;
632:   dydx = hy/hx;
633:   diagxy = 0.5 * (dxdy + dydx);
634:   bandxy = -0.5 * dxdy;
635:   bandyx = -0.5 * dydx;

637:   info = DAGetLocalVector(da, &localX); CHKERRQ(info);
638:   info = MatAssembled(H,&assembled); CHKERRQ(info);
639:   if (assembled){info = MatZeroEntries(H);  CHKERRQ(info);}

641:   info = DAGlobalToLocalBegin(da, X, INSERT_VALUES, localX); CHKERRQ(info);
642:   info = DAGlobalToLocalEnd(da, X, INSERT_VALUES, localX); CHKERRQ(info);

644:   info = DAVecGetArray(da, localX, (void**)&x); CHKERRQ(info);

646:   info = DAGetCorners(da, &xs, &ys, TAO_NULL, &xm, &ym, TAO_NULL); CHKERRQ(info);
647:   info = DAGetGhostCorners(da, &gxs, &gys, TAO_NULL, &gxm, &gym, TAO_NULL); CHKERRQ(info);

649:   xe = gxs + gxm - 1;
650:   ye = gys + gym - 1;
651:   for (j = ys; j < ye; j++) {
652:     for (i = xs; i < xe; i++) {

654:           /* Hessian contribution at 0,0 */
655:       dexp = exp(x[j][i]) * area * lambdad3;
656:       smallH[0][0] = diagxy - dexp;
657:       smallH[0][1] = smallH[1][0] = bandyx;
658:       smallH[0][2] = smallH[2][0] = bandxy;
659:       smallH[0][3] = smallH[3][0] = 0.0;

661:           /* Hessian contribution at 1,0 */
662:       dexp = exp(x[j][i+1]) * area * 2.0 * lambdad3;
663:       smallH[1][1] = diagxy - dexp;
664:       smallH[1][2] = smallH[2][1] = 0.0;
665:       smallH[1][3] = smallH[3][1] = bandxy;

667:           /* Hessian contribution at 0,1 */
668:       dexp = exp(x[j+1][i]) * area * 2.0 * lambdad3;
669:       smallH[2][2] = diagxy - dexp;
670:       smallH[2][3] = smallH[3][2] = bandyx;

672:           /* Hessian contribution at 1,1 */
673:       dexp = exp(x[j+1][i+1]) * area * lambdad3;
674:       smallH[3][3] = diagxy - dexp;

676:       ind[0] = (j-gys) * gxm + (i-gxs);
677:       ind[1] = ind[0] + 1;
678:       ind[2] = ind[0] + gxm;
679:       ind[3] = ind[2] + 1;
680:       info = MatSetValuesLocal(H,4,ind,4,ind,(PetscScalar*)smallH,ADD_VALUES); CHKERRQ(info);

682:     }
683:   }

685:   info = DAVecRestoreArray(da, localX, (void**)&x); CHKERRQ(info);

687:   info = MatAssemblyBegin(H, MAT_FINAL_ASSEMBLY); CHKERRQ(info);
688:   info = MatAssemblyEnd(H, MAT_FINAL_ASSEMBLY); CHKERRQ(info);
689:   info = MatSetOption(H, MAT_SYMMETRIC); CHKERRQ(info);

691:   info = DARestoreLocalVector(da, &localX); CHKERRQ(info);

693:   info = PetscLogFlops((xe-xs) * (ye-ys) * 14 + 7); CHKERRQ(info);
694:   return 0;

696: } /* WholeCombHessian */