1 2 #include <../src/snes/impls/vi/viimpl.h> /*I "petscsnes.h" I*/ 3 #include <../include/private/kspimpl.h> 4 #include <../include/private/matimpl.h> 5 #include <../include/private/dmimpl.h> 6 7 #undef __FUNCT__ 8 #define __FUNCT__ "SNESVISetComputeVariableBounds" 9 /*@C 10 SNESVISetComputeVariableBounds - Sets a function that is called to compute the variable bounds 11 12 Input parameter 13 + snes - the SNES context 14 - compute - computes the bounds 15 16 17 @*/ 18 PetscErrorCode SNESVISetComputeVariableBounds(SNES snes, PetscErrorCode (*compute)(SNES,Vec,Vec)) 19 { 20 PetscErrorCode ierr; 21 SNES_VI *vi; 22 23 PetscFunctionBegin; 24 ierr = SNESSetType(snes,SNESVI);CHKERRQ(ierr); 25 vi = (SNES_VI*)snes->data; 26 vi->computevariablebounds = compute; 27 PetscFunctionReturn(0); 28 } 29 30 31 #undef __FUNCT__ 32 #define __FUNCT__ "SNESVIGetInActiveSetIS" 33 /* 34 SNESVIGetInActiveSetIS - Gets the global indices for the bogus inactive set variables 35 36 Input parameter 37 . snes - the SNES context 38 . X - the snes solution vector 39 40 Output parameter 41 . ISact - active set index set 42 43 */ 44 PetscErrorCode SNESVIGetInActiveSetIS(Vec upper,Vec lower,Vec X,Vec F,IS* inact) 45 { 46 PetscErrorCode ierr; 47 const PetscScalar *x,*xl,*xu,*f; 48 PetscInt *idx_act,i,nlocal,nloc_isact=0,ilow,ihigh,i1=0; 49 50 PetscFunctionBegin; 51 ierr = VecGetLocalSize(X,&nlocal);CHKERRQ(ierr); 52 ierr = VecGetOwnershipRange(X,&ilow,&ihigh);CHKERRQ(ierr); 53 ierr = VecGetArrayRead(X,&x);CHKERRQ(ierr); 54 ierr = VecGetArrayRead(lower,&xl);CHKERRQ(ierr); 55 ierr = VecGetArrayRead(upper,&xu);CHKERRQ(ierr); 56 ierr = VecGetArrayRead(F,&f);CHKERRQ(ierr); 57 /* Compute inactive set size */ 58 for (i=0; i < nlocal;i++) { 59 if (((PetscRealPart(x[i]) > PetscRealPart(xl[i]) + 1.e-8 || (PetscRealPart(f[i]) < 0.0)) && ((PetscRealPart(x[i]) < PetscRealPart(xu[i]) - 1.e-8) || PetscRealPart(f[i]) > 0.0))) nloc_isact++; 60 } 61 62 ierr = PetscMalloc(nloc_isact*sizeof(PetscInt),&idx_act);CHKERRQ(ierr); 63 64 /* Set inactive set indices */ 65 for(i=0; i < nlocal; i++) { 66 if (((PetscRealPart(x[i]) > PetscRealPart(xl[i]) + 1.e-8 || (PetscRealPart(f[i]) < 0.0)) && ((PetscRealPart(x[i]) < PetscRealPart(xu[i]) - 1.e-8) || PetscRealPart(f[i]) > 0.0))) idx_act[i1++] = ilow+i; 67 } 68 69 /* Create inactive set IS */ 70 ierr = ISCreateGeneral(((PetscObject)upper)->comm,nloc_isact,idx_act,PETSC_OWN_POINTER,inact);CHKERRQ(ierr); 71 72 ierr = VecRestoreArrayRead(X,&x);CHKERRQ(ierr); 73 ierr = VecRestoreArrayRead(lower,&xl);CHKERRQ(ierr); 74 ierr = VecRestoreArrayRead(upper,&xu);CHKERRQ(ierr); 75 ierr = VecRestoreArrayRead(F,&f);CHKERRQ(ierr); 76 PetscFunctionReturn(0); 77 } 78 79 /* 80 Provides a wrapper to a DM to allow it to be used to generated the interpolation/restriction from the DM for the smaller matrices and vectors 81 defined by the reduced space method. 82 83 Simple calls the regular DM interpolation and restricts it to operation on the variables not associated with active constraints. 84 85 */ 86 typedef struct { 87 PetscInt n; /* size of vectors in the reduced DM space */ 88 IS inactive; 89 Vec upper,lower,values,F; /* upper and lower bounds of all variables on this level, the values and the function values */ 90 PetscErrorCode (*getinterpolation)(DM,DM,Mat*,Vec*); /* DM's original routines */ 91 PetscErrorCode (*coarsen)(DM, MPI_Comm, DM*); 92 PetscErrorCode (*createglobalvector)(DM,Vec*); 93 DM dm; /* when destroying this object we need to reset the above function into the base DM */ 94 } DM_SNESVI; 95 96 #undef __FUNCT__ 97 #define __FUNCT__ "DMCreateGlobalVector_SNESVI" 98 /* 99 DMCreateGlobalVector_SNESVI - Creates global vector of the size of the reduced space 100 101 */ 102 PetscErrorCode DMCreateGlobalVector_SNESVI(DM dm,Vec *vec) 103 { 104 PetscErrorCode ierr; 105 PetscContainer isnes; 106 DM_SNESVI *dmsnesvi; 107 108 PetscFunctionBegin; 109 ierr = PetscObjectQuery((PetscObject)dm,"VI",(PetscObject *)&isnes);CHKERRQ(ierr); 110 if (!isnes) SETERRQ(((PetscObject)dm)->comm,PETSC_ERR_PLIB,"Composed SNES is missing"); 111 ierr = PetscContainerGetPointer(isnes,(void**)&dmsnesvi);CHKERRQ(ierr); 112 ierr = VecCreateMPI(((PetscObject)dm)->comm,dmsnesvi->n,PETSC_DETERMINE,vec);CHKERRQ(ierr); 113 PetscFunctionReturn(0); 114 } 115 116 #undef __FUNCT__ 117 #define __FUNCT__ "DMGetInterpolation_SNESVI" 118 /* 119 DMGetInterpolation_SNESVI - Modifieds the interpolation obtained from the DM by removing all rows and columns associated with active constraints. 120 121 */ 122 PetscErrorCode DMGetInterpolation_SNESVI(DM dm1,DM dm2,Mat *mat,Vec *vec) 123 { 124 PetscErrorCode ierr; 125 PetscContainer isnes; 126 DM_SNESVI *dmsnesvi1,*dmsnesvi2; 127 Mat interp; 128 129 PetscFunctionBegin; 130 ierr = PetscObjectQuery((PetscObject)dm1,"VI",(PetscObject *)&isnes);CHKERRQ(ierr); 131 if (!isnes) SETERRQ(((PetscObject)dm1)->comm,PETSC_ERR_PLIB,"Composed VI data structure is missing"); 132 ierr = PetscContainerGetPointer(isnes,(void**)&dmsnesvi1);CHKERRQ(ierr); 133 ierr = PetscObjectQuery((PetscObject)dm2,"VI",(PetscObject *)&isnes);CHKERRQ(ierr); 134 if (!isnes) SETERRQ(((PetscObject)dm2)->comm,PETSC_ERR_PLIB,"Composed VI data structure is missing"); 135 ierr = PetscContainerGetPointer(isnes,(void**)&dmsnesvi2);CHKERRQ(ierr); 136 137 ierr = (*dmsnesvi1->getinterpolation)(dm1,dm2,&interp,PETSC_NULL);CHKERRQ(ierr); 138 ierr = MatGetSubMatrix(interp,dmsnesvi2->inactive,dmsnesvi1->inactive,MAT_INITIAL_MATRIX,mat);CHKERRQ(ierr); 139 ierr = MatDestroy(&interp);CHKERRQ(ierr); 140 *vec = 0; 141 PetscFunctionReturn(0); 142 } 143 144 extern PetscErrorCode DMSetVI(DM,Vec,Vec,Vec,Vec,IS); 145 146 #undef __FUNCT__ 147 #define __FUNCT__ "DMCoarsen_SNESVI" 148 /* 149 DMCoarsen_SNESVI - Computes the regular coarsened DM then computes additional information about its inactive set 150 151 */ 152 PetscErrorCode DMCoarsen_SNESVI(DM dm1,MPI_Comm comm,DM *dm2) 153 { 154 PetscErrorCode ierr; 155 PetscContainer isnes; 156 DM_SNESVI *dmsnesvi1; 157 Vec upper,lower,values,F; 158 IS inactive; 159 VecScatter inject; 160 161 PetscFunctionBegin; 162 ierr = PetscObjectQuery((PetscObject)dm1,"VI",(PetscObject *)&isnes);CHKERRQ(ierr); 163 if (!isnes) SETERRQ(((PetscObject)dm1)->comm,PETSC_ERR_PLIB,"Composed VI data structure is missing"); 164 ierr = PetscContainerGetPointer(isnes,(void**)&dmsnesvi1);CHKERRQ(ierr); 165 166 /* get the original coarsen */ 167 ierr = (*dmsnesvi1->coarsen)(dm1,comm,dm2);CHKERRQ(ierr); 168 169 /* not sure why this extra reference is needed, but without the dm2 disappears too early */ 170 ierr = PetscObjectReference((PetscObject)*dm2);CHKERRQ(ierr); 171 172 /* need to set back global vectors in order to use the original injection */ 173 ierr = DMClearGlobalVectors(dm1);CHKERRQ(ierr); 174 dm1->ops->createglobalvector = dmsnesvi1->createglobalvector; 175 ierr = DMGetInjection(*dm2,dm1,&inject);CHKERRQ(ierr); 176 ierr = DMCreateGlobalVector(*dm2,&upper);CHKERRQ(ierr); 177 ierr = VecScatterBegin(inject,dmsnesvi1->upper,upper,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 178 ierr = VecScatterEnd(inject,dmsnesvi1->upper,upper,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 179 ierr = DMCreateGlobalVector(*dm2,&lower);CHKERRQ(ierr); 180 ierr = VecScatterBegin(inject,dmsnesvi1->lower,lower,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 181 ierr = VecScatterEnd(inject,dmsnesvi1->lower,lower,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 182 ierr = DMCreateGlobalVector(*dm2,&values);CHKERRQ(ierr); 183 ierr = VecScatterBegin(inject,dmsnesvi1->values,values,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 184 ierr = VecScatterEnd(inject,dmsnesvi1->values,values,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 185 ierr = DMCreateGlobalVector(*dm2,&F);CHKERRQ(ierr); 186 ierr = VecScatterBegin(inject,dmsnesvi1->F,F,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 187 ierr = VecScatterEnd(inject,dmsnesvi1->F,F,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 188 ierr = VecScatterDestroy(&inject);CHKERRQ(ierr); 189 ierr = DMClearGlobalVectors(dm1);CHKERRQ(ierr); 190 dm1->ops->createglobalvector = DMCreateGlobalVector_SNESVI; 191 ierr = SNESVIGetInActiveSetIS(upper,lower,values,F,&inactive);CHKERRQ(ierr); 192 ierr = DMSetVI(*dm2,upper,lower,values,F,inactive);CHKERRQ(ierr); 193 ierr = VecDestroy(&upper);CHKERRQ(ierr); 194 ierr = VecDestroy(&lower);CHKERRQ(ierr); 195 ierr = VecDestroy(&values);CHKERRQ(ierr); 196 ierr = VecDestroy(&F);CHKERRQ(ierr); 197 ierr = ISDestroy(&inactive);CHKERRQ(ierr); 198 PetscFunctionReturn(0); 199 } 200 201 #undef __FUNCT__ 202 #define __FUNCT__ "DMDestroy_SNESVI" 203 PetscErrorCode DMDestroy_SNESVI(DM_SNESVI *dmsnesvi) 204 { 205 PetscErrorCode ierr; 206 207 PetscFunctionBegin; 208 /* reset the base methods in the DM object that were changed when the DM_SNESVI was reset */ 209 dmsnesvi->dm->ops->getinterpolation = dmsnesvi->getinterpolation; 210 dmsnesvi->dm->ops->coarsen = dmsnesvi->coarsen; 211 dmsnesvi->dm->ops->createglobalvector = dmsnesvi->createglobalvector; 212 /* need to clear out this vectors because some of them may not have a reference to the DM 213 but they are counted as having references to the DM in DMDestroy() */ 214 ierr = DMClearGlobalVectors(dmsnesvi->dm);CHKERRQ(ierr); 215 216 ierr = VecDestroy(&dmsnesvi->upper);CHKERRQ(ierr); 217 ierr = VecDestroy(&dmsnesvi->lower);CHKERRQ(ierr); 218 ierr = VecDestroy(&dmsnesvi->values);CHKERRQ(ierr); 219 ierr = VecDestroy(&dmsnesvi->F);CHKERRQ(ierr); 220 ierr = ISDestroy(&dmsnesvi->inactive);CHKERRQ(ierr); 221 ierr = PetscFree(dmsnesvi);CHKERRQ(ierr); 222 PetscFunctionReturn(0); 223 } 224 225 #undef __FUNCT__ 226 #define __FUNCT__ "DMSetVI" 227 /* 228 DMSetVI - Marks a DM as associated with a VI problem. This causes the interpolation/restriction operators to 229 be restricted to only those variables NOT associated with active constraints. 230 231 */ 232 PetscErrorCode DMSetVI(DM dm,Vec upper,Vec lower,Vec values,Vec F,IS inactive) 233 { 234 PetscErrorCode ierr; 235 PetscContainer isnes; 236 DM_SNESVI *dmsnesvi; 237 238 PetscFunctionBegin; 239 if (!dm) PetscFunctionReturn(0); 240 241 ierr = PetscObjectReference((PetscObject)upper);CHKERRQ(ierr); 242 ierr = PetscObjectReference((PetscObject)lower);CHKERRQ(ierr); 243 ierr = PetscObjectReference((PetscObject)values);CHKERRQ(ierr); 244 ierr = PetscObjectReference((PetscObject)F);CHKERRQ(ierr); 245 ierr = PetscObjectReference((PetscObject)inactive);CHKERRQ(ierr); 246 247 ierr = PetscObjectQuery((PetscObject)dm,"VI",(PetscObject *)&isnes);CHKERRQ(ierr); 248 if (!isnes) { 249 ierr = PetscContainerCreate(((PetscObject)dm)->comm,&isnes);CHKERRQ(ierr); 250 ierr = PetscContainerSetUserDestroy(isnes,(PetscErrorCode (*)(void*))DMDestroy_SNESVI);CHKERRQ(ierr); 251 ierr = PetscNew(DM_SNESVI,&dmsnesvi);CHKERRQ(ierr); 252 ierr = PetscContainerSetPointer(isnes,(void*)dmsnesvi);CHKERRQ(ierr); 253 ierr = PetscObjectCompose((PetscObject)dm,"VI",(PetscObject)isnes);CHKERRQ(ierr); 254 ierr = PetscContainerDestroy(&isnes);CHKERRQ(ierr); 255 dmsnesvi->getinterpolation = dm->ops->getinterpolation; 256 dm->ops->getinterpolation = DMGetInterpolation_SNESVI; 257 dmsnesvi->coarsen = dm->ops->coarsen; 258 dm->ops->coarsen = DMCoarsen_SNESVI; 259 dmsnesvi->createglobalvector = dm->ops->createglobalvector; 260 dm->ops->createglobalvector = DMCreateGlobalVector_SNESVI; 261 /* since these vectors may reference the DM, need to remove circle referencing */ 262 ierr = PetscObjectRemoveReference((PetscObject)upper,"DM");CHKERRQ(ierr); 263 ierr = PetscObjectRemoveReference((PetscObject)lower,"DM");CHKERRQ(ierr); 264 ierr = PetscObjectRemoveReference((PetscObject)values,"DM");CHKERRQ(ierr); 265 ierr = PetscObjectRemoveReference((PetscObject)F,"DM");CHKERRQ(ierr); 266 } else { 267 ierr = PetscContainerGetPointer(isnes,(void**)&dmsnesvi);CHKERRQ(ierr); 268 ierr = VecDestroy(&dmsnesvi->upper);CHKERRQ(ierr); 269 ierr = VecDestroy(&dmsnesvi->lower);CHKERRQ(ierr); 270 ierr = VecDestroy(&dmsnesvi->values);CHKERRQ(ierr); 271 ierr = VecDestroy(&dmsnesvi->F);CHKERRQ(ierr); 272 ierr = ISDestroy(&dmsnesvi->inactive);CHKERRQ(ierr); 273 } 274 ierr = DMClearGlobalVectors(dm);CHKERRQ(ierr); 275 ierr = ISGetLocalSize(inactive,&dmsnesvi->n);CHKERRQ(ierr); 276 dmsnesvi->upper = upper; 277 dmsnesvi->lower = lower; 278 dmsnesvi->values = values; 279 dmsnesvi->F = F; 280 dmsnesvi->inactive = inactive; 281 dmsnesvi->dm = dm; 282 PetscFunctionReturn(0); 283 } 284 285 #undef __FUNCT__ 286 #define __FUNCT__ "DMDestroyVI" 287 /* 288 DMDestroyVI - Frees the DM_SNESVI object contained in the DM 289 - also resets the function pointers in the DM for getinterpolation() etc to use the original DM 290 */ 291 PetscErrorCode DMDestroyVI(DM dm) 292 { 293 PetscErrorCode ierr; 294 295 PetscFunctionBegin; 296 if (!dm) PetscFunctionReturn(0); 297 ierr = PetscObjectCompose((PetscObject)dm,"VI",(PetscObject)PETSC_NULL);CHKERRQ(ierr); 298 PetscFunctionReturn(0); 299 } 300 301 /* --------------------------------------------------------------------------------------------------------*/ 302 303 #undef __FUNCT__ 304 #define __FUNCT__ "SNESMonitorVI" 305 PetscErrorCode SNESMonitorVI(SNES snes,PetscInt its,PetscReal fgnorm,void *dummy) 306 { 307 PetscErrorCode ierr; 308 SNES_VI *vi = (SNES_VI*)snes->data; 309 PetscViewer viewer = dummy ? (PetscViewer) dummy : PETSC_VIEWER_STDOUT_(((PetscObject)snes)->comm); 310 const PetscScalar *x,*xl,*xu,*f; 311 PetscInt i,n,act = 0; 312 PetscReal rnorm,fnorm; 313 314 PetscFunctionBegin; 315 ierr = VecGetLocalSize(snes->vec_sol,&n);CHKERRQ(ierr); 316 ierr = VecGetArrayRead(vi->xl,&xl);CHKERRQ(ierr); 317 ierr = VecGetArrayRead(vi->xu,&xu);CHKERRQ(ierr); 318 ierr = VecGetArrayRead(snes->vec_sol,&x);CHKERRQ(ierr); 319 ierr = VecGetArrayRead(snes->vec_func,&f);CHKERRQ(ierr); 320 321 rnorm = 0.0; 322 for (i=0; i<n; i++) { 323 if (((PetscRealPart(x[i]) > PetscRealPart(xl[i]) + 1.e-8 || (PetscRealPart(f[i]) < 0.0)) && ((PetscRealPart(x[i]) < PetscRealPart(xu[i]) - 1.e-8) || PetscRealPart(f[i]) > 0.0))) rnorm += PetscRealPart(PetscConj(f[i])*f[i]); 324 else act++; 325 } 326 ierr = VecRestoreArrayRead(snes->vec_func,&f);CHKERRQ(ierr); 327 ierr = VecRestoreArrayRead(vi->xl,&xl);CHKERRQ(ierr); 328 ierr = VecRestoreArrayRead(vi->xu,&xu);CHKERRQ(ierr); 329 ierr = VecRestoreArrayRead(snes->vec_sol,&x);CHKERRQ(ierr); 330 ierr = MPI_Allreduce(&rnorm,&fnorm,1,MPIU_REAL,MPIU_SUM,((PetscObject)snes)->comm);CHKERRQ(ierr); 331 fnorm = sqrt(fnorm); 332 ierr = PetscViewerASCIIAddTab(viewer,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 333 ierr = PetscViewerASCIIPrintf(viewer,"%3D SNES VI Function norm %14.12e Active constraints %D\n",its,fnorm,act);CHKERRQ(ierr); 334 ierr = PetscViewerASCIISubtractTab(viewer,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 335 PetscFunctionReturn(0); 336 } 337 338 /* 339 Checks if J^T F = 0 which implies we've found a local minimum of the norm of the function, 340 || F(u) ||_2 but not a zero, F(u) = 0. In the case when one cannot compute J^T F we use the fact that 341 0 = (J^T F)^T W = F^T J W iff W not in the null space of J. Thanks for Jorge More 342 for this trick. One assumes that the probability that W is in the null space of J is very, very small. 343 */ 344 #undef __FUNCT__ 345 #define __FUNCT__ "SNESVICheckLocalMin_Private" 346 PetscErrorCode SNESVICheckLocalMin_Private(SNES snes,Mat A,Vec F,Vec W,PetscReal fnorm,PetscBool *ismin) 347 { 348 PetscReal a1; 349 PetscErrorCode ierr; 350 PetscBool hastranspose; 351 352 PetscFunctionBegin; 353 *ismin = PETSC_FALSE; 354 ierr = MatHasOperation(A,MATOP_MULT_TRANSPOSE,&hastranspose);CHKERRQ(ierr); 355 if (hastranspose) { 356 /* Compute || J^T F|| */ 357 ierr = MatMultTranspose(A,F,W);CHKERRQ(ierr); 358 ierr = VecNorm(W,NORM_2,&a1);CHKERRQ(ierr); 359 ierr = PetscInfo1(snes,"|| J^T F|| %G near zero implies found a local minimum\n",a1/fnorm);CHKERRQ(ierr); 360 if (a1/fnorm < 1.e-4) *ismin = PETSC_TRUE; 361 } else { 362 Vec work; 363 PetscScalar result; 364 PetscReal wnorm; 365 366 ierr = VecSetRandom(W,PETSC_NULL);CHKERRQ(ierr); 367 ierr = VecNorm(W,NORM_2,&wnorm);CHKERRQ(ierr); 368 ierr = VecDuplicate(W,&work);CHKERRQ(ierr); 369 ierr = MatMult(A,W,work);CHKERRQ(ierr); 370 ierr = VecDot(F,work,&result);CHKERRQ(ierr); 371 ierr = VecDestroy(&work);CHKERRQ(ierr); 372 a1 = PetscAbsScalar(result)/(fnorm*wnorm); 373 ierr = PetscInfo1(snes,"(F^T J random)/(|| F ||*||random|| %G near zero implies found a local minimum\n",a1);CHKERRQ(ierr); 374 if (a1 < 1.e-4) *ismin = PETSC_TRUE; 375 } 376 PetscFunctionReturn(0); 377 } 378 379 /* 380 Checks if J^T(F - J*X) = 0 381 */ 382 #undef __FUNCT__ 383 #define __FUNCT__ "SNESVICheckResidual_Private" 384 PetscErrorCode SNESVICheckResidual_Private(SNES snes,Mat A,Vec F,Vec X,Vec W1,Vec W2) 385 { 386 PetscReal a1,a2; 387 PetscErrorCode ierr; 388 PetscBool hastranspose; 389 390 PetscFunctionBegin; 391 ierr = MatHasOperation(A,MATOP_MULT_TRANSPOSE,&hastranspose);CHKERRQ(ierr); 392 if (hastranspose) { 393 ierr = MatMult(A,X,W1);CHKERRQ(ierr); 394 ierr = VecAXPY(W1,-1.0,F);CHKERRQ(ierr); 395 396 /* Compute || J^T W|| */ 397 ierr = MatMultTranspose(A,W1,W2);CHKERRQ(ierr); 398 ierr = VecNorm(W1,NORM_2,&a1);CHKERRQ(ierr); 399 ierr = VecNorm(W2,NORM_2,&a2);CHKERRQ(ierr); 400 if (a1 != 0.0) { 401 ierr = PetscInfo1(snes,"||J^T(F-Ax)||/||F-AX|| %G near zero implies inconsistent rhs\n",a2/a1);CHKERRQ(ierr); 402 } 403 } 404 PetscFunctionReturn(0); 405 } 406 407 /* 408 SNESDefaultConverged_VI - Checks the convergence of the semismooth newton algorithm. 409 410 Notes: 411 The convergence criterion currently implemented is 412 merit < abstol 413 merit < rtol*merit_initial 414 */ 415 #undef __FUNCT__ 416 #define __FUNCT__ "SNESDefaultConverged_VI" 417 PetscErrorCode SNESDefaultConverged_VI(SNES snes,PetscInt it,PetscReal xnorm,PetscReal gradnorm,PetscReal fnorm,SNESConvergedReason *reason,void *dummy) 418 { 419 PetscErrorCode ierr; 420 421 PetscFunctionBegin; 422 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 423 PetscValidPointer(reason,6); 424 425 *reason = SNES_CONVERGED_ITERATING; 426 427 if (!it) { 428 /* set parameter for default relative tolerance convergence test */ 429 snes->ttol = fnorm*snes->rtol; 430 } 431 if (fnorm != fnorm) { 432 ierr = PetscInfo(snes,"Failed to converged, function norm is NaN\n");CHKERRQ(ierr); 433 *reason = SNES_DIVERGED_FNORM_NAN; 434 } else if (fnorm < snes->abstol) { 435 ierr = PetscInfo2(snes,"Converged due to function norm %G < %G\n",fnorm,snes->abstol);CHKERRQ(ierr); 436 *reason = SNES_CONVERGED_FNORM_ABS; 437 } else if (snes->nfuncs >= snes->max_funcs) { 438 ierr = PetscInfo2(snes,"Exceeded maximum number of function evaluations: %D > %D\n",snes->nfuncs,snes->max_funcs);CHKERRQ(ierr); 439 *reason = SNES_DIVERGED_FUNCTION_COUNT; 440 } 441 442 if (it && !*reason) { 443 if (fnorm < snes->ttol) { 444 ierr = PetscInfo2(snes,"Converged due to function norm %G < %G (relative tolerance)\n",fnorm,snes->ttol);CHKERRQ(ierr); 445 *reason = SNES_CONVERGED_FNORM_RELATIVE; 446 } 447 } 448 PetscFunctionReturn(0); 449 } 450 451 /* 452 SNESVIComputeMeritFunction - Evaluates the merit function for the mixed complementarity problem. 453 454 Input Parameter: 455 . phi - the semismooth function 456 457 Output Parameter: 458 . merit - the merit function 459 . phinorm - ||phi|| 460 461 Notes: 462 The merit function for the mixed complementarity problem is defined as 463 merit = 0.5*phi^T*phi 464 */ 465 #undef __FUNCT__ 466 #define __FUNCT__ "SNESVIComputeMeritFunction" 467 static PetscErrorCode SNESVIComputeMeritFunction(Vec phi, PetscReal* merit,PetscReal* phinorm) 468 { 469 PetscErrorCode ierr; 470 471 PetscFunctionBegin; 472 ierr = VecNormBegin(phi,NORM_2,phinorm);CHKERRQ(ierr); 473 ierr = VecNormEnd(phi,NORM_2,phinorm);CHKERRQ(ierr); 474 475 *merit = 0.5*(*phinorm)*(*phinorm); 476 PetscFunctionReturn(0); 477 } 478 479 PETSC_STATIC_INLINE PetscScalar Phi(PetscScalar a,PetscScalar b) 480 { 481 return a + b - sqrt(a*a + b*b); 482 } 483 484 PETSC_STATIC_INLINE PetscScalar DPhi(PetscScalar a,PetscScalar b) 485 { 486 if ((PetscAbsScalar(a) >= 1.e-6) || (PetscAbsScalar(b) >= 1.e-6)) return 1.0 - a/ sqrt(a*a + b*b); 487 else return .5; 488 } 489 490 /* 491 SNESVIComputeFunction - Reformulates a system of nonlinear equations in mixed complementarity form to a system of nonlinear equations in semismooth form. 492 493 Input Parameters: 494 . snes - the SNES context 495 . x - current iterate 496 . functx - user defined function context 497 498 Output Parameters: 499 . phi - Semismooth function 500 501 */ 502 #undef __FUNCT__ 503 #define __FUNCT__ "SNESVIComputeFunction" 504 static PetscErrorCode SNESVIComputeFunction(SNES snes,Vec X,Vec phi,void* functx) 505 { 506 PetscErrorCode ierr; 507 SNES_VI *vi = (SNES_VI*)snes->data; 508 Vec Xl = vi->xl,Xu = vi->xu,F = snes->vec_func; 509 PetscScalar *phi_arr,*x_arr,*f_arr,*l,*u; 510 PetscInt i,nlocal; 511 512 PetscFunctionBegin; 513 ierr = (*vi->computeuserfunction)(snes,X,F,functx);CHKERRQ(ierr); 514 ierr = VecGetLocalSize(X,&nlocal);CHKERRQ(ierr); 515 ierr = VecGetArray(X,&x_arr);CHKERRQ(ierr); 516 ierr = VecGetArray(F,&f_arr);CHKERRQ(ierr); 517 ierr = VecGetArray(Xl,&l);CHKERRQ(ierr); 518 ierr = VecGetArray(Xu,&u);CHKERRQ(ierr); 519 ierr = VecGetArray(phi,&phi_arr);CHKERRQ(ierr); 520 521 for (i=0;i < nlocal;i++) { 522 if ((PetscRealPart(l[i]) <= SNES_VI_NINF) && (PetscRealPart(u[i]) >= SNES_VI_INF)) { /* no constraints on variable */ 523 phi_arr[i] = f_arr[i]; 524 } else if (PetscRealPart(l[i]) <= SNES_VI_NINF) { /* upper bound on variable only */ 525 phi_arr[i] = -Phi(u[i] - x_arr[i],-f_arr[i]); 526 } else if (PetscRealPart(u[i]) >= SNES_VI_INF) { /* lower bound on variable only */ 527 phi_arr[i] = Phi(x_arr[i] - l[i],f_arr[i]); 528 } else if (l[i] == u[i]) { 529 phi_arr[i] = l[i] - x_arr[i]; 530 } else { /* both bounds on variable */ 531 phi_arr[i] = Phi(x_arr[i] - l[i],-Phi(u[i] - x_arr[i],-f_arr[i])); 532 } 533 } 534 535 ierr = VecRestoreArray(X,&x_arr);CHKERRQ(ierr); 536 ierr = VecRestoreArray(F,&f_arr);CHKERRQ(ierr); 537 ierr = VecRestoreArray(Xl,&l);CHKERRQ(ierr); 538 ierr = VecRestoreArray(Xu,&u);CHKERRQ(ierr); 539 ierr = VecRestoreArray(phi,&phi_arr);CHKERRQ(ierr); 540 PetscFunctionReturn(0); 541 } 542 543 /* 544 SNESVIComputeBsubdifferentialVectors - Computes the diagonal shift (Da) and row scaling (Db) vectors needed for the 545 the semismooth jacobian. 546 */ 547 #undef __FUNCT__ 548 #define __FUNCT__ "SNESVIComputeBsubdifferentialVectors" 549 PetscErrorCode SNESVIComputeBsubdifferentialVectors(SNES snes,Vec X,Vec F,Mat jac,Vec Da,Vec Db) 550 { 551 PetscErrorCode ierr; 552 SNES_VI *vi = (SNES_VI*)snes->data; 553 PetscScalar *l,*u,*x,*f,*da,*db,da1,da2,db1,db2; 554 PetscInt i,nlocal; 555 556 PetscFunctionBegin; 557 558 ierr = VecGetArray(X,&x);CHKERRQ(ierr); 559 ierr = VecGetArray(F,&f);CHKERRQ(ierr); 560 ierr = VecGetArray(vi->xl,&l);CHKERRQ(ierr); 561 ierr = VecGetArray(vi->xu,&u);CHKERRQ(ierr); 562 ierr = VecGetArray(Da,&da);CHKERRQ(ierr); 563 ierr = VecGetArray(Db,&db);CHKERRQ(ierr); 564 ierr = VecGetLocalSize(X,&nlocal);CHKERRQ(ierr); 565 566 for (i=0;i< nlocal;i++) { 567 if ((PetscRealPart(l[i]) <= SNES_VI_NINF) && (PetscRealPart(u[i]) >= SNES_VI_INF)) {/* no constraints on variable */ 568 da[i] = 0; 569 db[i] = 1; 570 } else if (PetscRealPart(l[i]) <= SNES_VI_NINF) { /* upper bound on variable only */ 571 da[i] = DPhi(u[i] - x[i], -f[i]); 572 db[i] = DPhi(-f[i],u[i] - x[i]); 573 } else if (PetscRealPart(u[i]) >= SNES_VI_INF) { /* lower bound on variable only */ 574 da[i] = DPhi(x[i] - l[i], f[i]); 575 db[i] = DPhi(f[i],x[i] - l[i]); 576 } else if (l[i] == u[i]) { /* fixed variable */ 577 da[i] = 1; 578 db[i] = 0; 579 } else { /* upper and lower bounds on variable */ 580 da1 = DPhi(x[i] - l[i], -Phi(u[i] - x[i], -f[i])); 581 db1 = DPhi(-Phi(u[i] - x[i], -f[i]),x[i] - l[i]); 582 da2 = DPhi(u[i] - x[i], -f[i]); 583 db2 = DPhi(-f[i],u[i] - x[i]); 584 da[i] = da1 + db1*da2; 585 db[i] = db1*db2; 586 } 587 } 588 589 ierr = VecRestoreArray(X,&x);CHKERRQ(ierr); 590 ierr = VecRestoreArray(F,&f);CHKERRQ(ierr); 591 ierr = VecRestoreArray(vi->xl,&l);CHKERRQ(ierr); 592 ierr = VecRestoreArray(vi->xu,&u);CHKERRQ(ierr); 593 ierr = VecRestoreArray(Da,&da);CHKERRQ(ierr); 594 ierr = VecRestoreArray(Db,&db);CHKERRQ(ierr); 595 PetscFunctionReturn(0); 596 } 597 598 /* 599 SNESVIComputeJacobian - Computes the jacobian of the semismooth function.The Jacobian for the semismooth function is an element of the B-subdifferential of the Fischer-Burmeister function for complementarity problems. 600 601 Input Parameters: 602 . Da - Diagonal shift vector for the semismooth jacobian. 603 . Db - Row scaling vector for the semismooth jacobian. 604 605 Output Parameters: 606 . jac - semismooth jacobian 607 . jac_pre - optional preconditioning matrix 608 609 Notes: 610 The semismooth jacobian matrix is given by 611 jac = Da + Db*jacfun 612 where Db is the row scaling matrix stored as a vector, 613 Da is the diagonal perturbation matrix stored as a vector 614 and jacfun is the jacobian of the original nonlinear function. 615 */ 616 #undef __FUNCT__ 617 #define __FUNCT__ "SNESVIComputeJacobian" 618 PetscErrorCode SNESVIComputeJacobian(Mat jac, Mat jac_pre,Vec Da, Vec Db) 619 { 620 PetscErrorCode ierr; 621 622 /* Do row scaling and add diagonal perturbation */ 623 ierr = MatDiagonalScale(jac,Db,PETSC_NULL);CHKERRQ(ierr); 624 ierr = MatDiagonalSet(jac,Da,ADD_VALUES);CHKERRQ(ierr); 625 if (jac != jac_pre) { /* If jac and jac_pre are different */ 626 ierr = MatDiagonalScale(jac_pre,Db,PETSC_NULL); 627 ierr = MatDiagonalSet(jac_pre,Da,ADD_VALUES);CHKERRQ(ierr); 628 } 629 PetscFunctionReturn(0); 630 } 631 632 /* 633 SNESVIComputeMeritFunctionGradient - Computes the gradient of the merit function psi. 634 635 Input Parameters: 636 phi - semismooth function. 637 H - semismooth jacobian 638 639 Output Parameters: 640 dpsi - merit function gradient 641 642 Notes: 643 The merit function gradient is computed as follows 644 dpsi = H^T*phi 645 */ 646 #undef __FUNCT__ 647 #define __FUNCT__ "SNESVIComputeMeritFunctionGradient" 648 PetscErrorCode SNESVIComputeMeritFunctionGradient(Mat H, Vec phi, Vec dpsi) 649 { 650 PetscErrorCode ierr; 651 652 PetscFunctionBegin; 653 ierr = MatMultTranspose(H,phi,dpsi);CHKERRQ(ierr); 654 PetscFunctionReturn(0); 655 } 656 657 /* -------------------------------------------------------------------------- */ 658 /* 659 SNESVIProjectOntoBounds - Projects X onto the feasible region so that Xl[i] <= X[i] <= Xu[i] for i = 1...n. 660 661 Input Parameters: 662 . SNES - nonlinear solver context 663 664 Output Parameters: 665 . X - Bound projected X 666 667 */ 668 669 #undef __FUNCT__ 670 #define __FUNCT__ "SNESVIProjectOntoBounds" 671 PetscErrorCode SNESVIProjectOntoBounds(SNES snes,Vec X) 672 { 673 PetscErrorCode ierr; 674 SNES_VI *vi = (SNES_VI*)snes->data; 675 const PetscScalar *xl,*xu; 676 PetscScalar *x; 677 PetscInt i,n; 678 679 PetscFunctionBegin; 680 ierr = VecGetLocalSize(X,&n);CHKERRQ(ierr); 681 ierr = VecGetArray(X,&x);CHKERRQ(ierr); 682 ierr = VecGetArrayRead(vi->xl,&xl);CHKERRQ(ierr); 683 ierr = VecGetArrayRead(vi->xu,&xu);CHKERRQ(ierr); 684 685 for(i = 0;i<n;i++) { 686 if (PetscRealPart(x[i]) < PetscRealPart(xl[i])) x[i] = xl[i]; 687 else if (PetscRealPart(x[i]) > PetscRealPart(xu[i])) x[i] = xu[i]; 688 } 689 ierr = VecRestoreArray(X,&x);CHKERRQ(ierr); 690 ierr = VecRestoreArrayRead(vi->xl,&xl);CHKERRQ(ierr); 691 ierr = VecRestoreArrayRead(vi->xu,&xu);CHKERRQ(ierr); 692 PetscFunctionReturn(0); 693 } 694 695 /* -------------------------------------------------------------------- 696 697 This file implements a semismooth truncated Newton method with a line search, 698 for solving a system of nonlinear equations in complementarity form, using the KSP, Vec, 699 and Mat interfaces for linear solvers, vectors, and matrices, 700 respectively. 701 702 The following basic routines are required for each nonlinear solver: 703 SNESCreate_XXX() - Creates a nonlinear solver context 704 SNESSetFromOptions_XXX() - Sets runtime options 705 SNESSolve_XXX() - Solves the nonlinear system 706 SNESDestroy_XXX() - Destroys the nonlinear solver context 707 The suffix "_XXX" denotes a particular implementation, in this case 708 we use _VI (e.g., SNESCreate_VI, SNESSolve_VI) for solving 709 systems of nonlinear equations with a line search (LS) method. 710 These routines are actually called via the common user interface 711 routines SNESCreate(), SNESSetFromOptions(), SNESSolve(), and 712 SNESDestroy(), so the application code interface remains identical 713 for all nonlinear solvers. 714 715 Another key routine is: 716 SNESSetUp_XXX() - Prepares for the use of a nonlinear solver 717 by setting data structures and options. The interface routine SNESSetUp() 718 is not usually called directly by the user, but instead is called by 719 SNESSolve() if necessary. 720 721 Additional basic routines are: 722 SNESView_XXX() - Prints details of runtime options that 723 have actually been used. 724 These are called by application codes via the interface routines 725 SNESView(). 726 727 The various types of solvers (preconditioners, Krylov subspace methods, 728 nonlinear solvers, timesteppers) are all organized similarly, so the 729 above description applies to these categories also. 730 731 -------------------------------------------------------------------- */ 732 /* 733 SNESSolveVI_SS - Solves the complementarity problem with a semismooth Newton 734 method using a line search. 735 736 Input Parameters: 737 . snes - the SNES context 738 739 Output Parameter: 740 . outits - number of iterations until termination 741 742 Application Interface Routine: SNESSolve() 743 744 Notes: 745 This implements essentially a semismooth Newton method with a 746 line search. The default line search does not do any line seach 747 but rather takes a full newton step. 748 */ 749 #undef __FUNCT__ 750 #define __FUNCT__ "SNESSolveVI_SS" 751 PetscErrorCode SNESSolveVI_SS(SNES snes) 752 { 753 SNES_VI *vi = (SNES_VI*)snes->data; 754 PetscErrorCode ierr; 755 PetscInt maxits,i,lits; 756 PetscBool lssucceed; 757 MatStructure flg = DIFFERENT_NONZERO_PATTERN; 758 PetscReal gnorm,xnorm=0,ynorm; 759 Vec Y,X,F,G,W; 760 KSPConvergedReason kspreason; 761 762 PetscFunctionBegin; 763 vi->computeuserfunction = snes->ops->computefunction; 764 snes->ops->computefunction = SNESVIComputeFunction; 765 766 snes->numFailures = 0; 767 snes->numLinearSolveFailures = 0; 768 snes->reason = SNES_CONVERGED_ITERATING; 769 770 maxits = snes->max_its; /* maximum number of iterations */ 771 X = snes->vec_sol; /* solution vector */ 772 F = snes->vec_func; /* residual vector */ 773 Y = snes->work[0]; /* work vectors */ 774 G = snes->work[1]; 775 W = snes->work[2]; 776 777 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 778 snes->iter = 0; 779 snes->norm = 0.0; 780 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 781 782 ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr); 783 ierr = SNESComputeFunction(snes,X,vi->phi);CHKERRQ(ierr); 784 if (snes->domainerror) { 785 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 786 snes->ops->computefunction = vi->computeuserfunction; 787 PetscFunctionReturn(0); 788 } 789 /* Compute Merit function */ 790 ierr = SNESVIComputeMeritFunction(vi->phi,&vi->merit,&vi->phinorm);CHKERRQ(ierr); 791 792 ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr); /* xnorm <- ||x|| */ 793 ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr); 794 if (PetscIsInfOrNanReal(vi->merit)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 795 796 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 797 snes->norm = vi->phinorm; 798 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 799 SNESLogConvHistory(snes,vi->phinorm,0); 800 ierr = SNESMonitor(snes,0,vi->phinorm);CHKERRQ(ierr); 801 802 /* set parameter for default relative tolerance convergence test */ 803 snes->ttol = vi->phinorm*snes->rtol; 804 /* test convergence */ 805 ierr = (*snes->ops->converged)(snes,0,0.0,0.0,vi->phinorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 806 if (snes->reason) { 807 snes->ops->computefunction = vi->computeuserfunction; 808 PetscFunctionReturn(0); 809 } 810 811 for (i=0; i<maxits; i++) { 812 813 /* Call general purpose update function */ 814 if (snes->ops->update) { 815 ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr); 816 } 817 818 /* Solve J Y = Phi, where J is the semismooth jacobian */ 819 /* Get the nonlinear function jacobian */ 820 ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr); 821 /* Get the diagonal shift and row scaling vectors */ 822 ierr = SNESVIComputeBsubdifferentialVectors(snes,X,F,snes->jacobian,vi->Da,vi->Db);CHKERRQ(ierr); 823 /* Compute the semismooth jacobian */ 824 ierr = SNESVIComputeJacobian(snes->jacobian,snes->jacobian_pre,vi->Da,vi->Db);CHKERRQ(ierr); 825 /* Compute the merit function gradient */ 826 ierr = SNESVIComputeMeritFunctionGradient(snes->jacobian,vi->phi,vi->dpsi);CHKERRQ(ierr); 827 ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre,flg);CHKERRQ(ierr); 828 ierr = SNES_KSPSolve(snes,snes->ksp,vi->phi,Y);CHKERRQ(ierr); 829 ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr); 830 831 if (kspreason < 0) { 832 if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) { 833 ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr); 834 snes->reason = SNES_DIVERGED_LINEAR_SOLVE; 835 break; 836 } 837 } 838 ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr); 839 snes->linear_its += lits; 840 ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr); 841 /* 842 if (vi->precheckstep) { 843 PetscBool changed_y = PETSC_FALSE; 844 ierr = (*vi->precheckstep)(snes,X,Y,vi->precheck,&changed_y);CHKERRQ(ierr); 845 } 846 847 if (PetscLogPrintInfo){ 848 ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr); 849 } 850 */ 851 /* Compute a (scaled) negative update in the line search routine: 852 Y <- X - lambda*Y 853 and evaluate G = function(Y) (depends on the line search). 854 */ 855 ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr); 856 ynorm = 1; gnorm = vi->phinorm; 857 ierr = (*vi->LineSearch)(snes,vi->lsP,X,vi->phi,G,Y,W,vi->phinorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr); 858 ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",vi->phinorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr); 859 if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break; 860 if (snes->domainerror) { 861 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 862 snes->ops->computefunction = vi->computeuserfunction; 863 PetscFunctionReturn(0); 864 } 865 if (!lssucceed) { 866 if (++snes->numFailures >= snes->maxFailures) { 867 PetscBool ismin; 868 snes->reason = SNES_DIVERGED_LINE_SEARCH; 869 ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr); 870 if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN; 871 break; 872 } 873 } 874 /* Update function and solution vectors */ 875 vi->phinorm = gnorm; 876 vi->merit = 0.5*vi->phinorm*vi->phinorm; 877 ierr = VecCopy(G,vi->phi);CHKERRQ(ierr); 878 ierr = VecCopy(W,X);CHKERRQ(ierr); 879 /* Monitor convergence */ 880 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 881 snes->iter = i+1; 882 snes->norm = vi->phinorm; 883 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 884 SNESLogConvHistory(snes,snes->norm,lits); 885 ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr); 886 /* Test for convergence, xnorm = || X || */ 887 if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); } 888 ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,vi->phinorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 889 if (snes->reason) break; 890 } 891 if (i == maxits) { 892 ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr); 893 if(!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT; 894 } 895 snes->ops->computefunction = vi->computeuserfunction; 896 PetscFunctionReturn(0); 897 } 898 899 #undef __FUNCT__ 900 #define __FUNCT__ "SNESVIGetActiveSetIS" 901 /* 902 SNESVIGetActiveSetIndices - Gets the global indices for the active set variables 903 904 Input parameter 905 . snes - the SNES context 906 . X - the snes solution vector 907 . F - the nonlinear function vector 908 909 Output parameter 910 . ISact - active set index set 911 */ 912 PetscErrorCode SNESVIGetActiveSetIS(SNES snes,Vec X,Vec F,IS* ISact) 913 { 914 PetscErrorCode ierr; 915 SNES_VI *vi = (SNES_VI*)snes->data; 916 Vec Xl=vi->xl,Xu=vi->xu; 917 const PetscScalar *x,*f,*xl,*xu; 918 PetscInt *idx_act,i,nlocal,nloc_isact=0,ilow,ihigh,i1=0; 919 920 PetscFunctionBegin; 921 ierr = VecGetLocalSize(X,&nlocal);CHKERRQ(ierr); 922 ierr = VecGetOwnershipRange(X,&ilow,&ihigh);CHKERRQ(ierr); 923 ierr = VecGetArrayRead(X,&x);CHKERRQ(ierr); 924 ierr = VecGetArrayRead(Xl,&xl);CHKERRQ(ierr); 925 ierr = VecGetArrayRead(Xu,&xu);CHKERRQ(ierr); 926 ierr = VecGetArrayRead(F,&f);CHKERRQ(ierr); 927 /* Compute active set size */ 928 for (i=0; i < nlocal;i++) { 929 if (!((PetscRealPart(x[i]) > PetscRealPart(xl[i]) + 1.e-8 || (PetscRealPart(f[i]) < 0.0)) && ((PetscRealPart(x[i]) < PetscRealPart(xu[i]) - 1.e-8) || PetscRealPart(f[i]) > 0.0))) nloc_isact++; 930 } 931 932 ierr = PetscMalloc(nloc_isact*sizeof(PetscInt),&idx_act);CHKERRQ(ierr); 933 934 /* Set active set indices */ 935 for(i=0; i < nlocal; i++) { 936 if (!((PetscRealPart(x[i]) > PetscRealPart(xl[i]) + 1.e-8 || (PetscRealPart(f[i]) < 0.0)) && ((PetscRealPart(x[i]) < PetscRealPart(xu[i]) - 1.e-8) || PetscRealPart(f[i]) > 0.0))) idx_act[i1++] = ilow+i; 937 } 938 939 /* Create active set IS */ 940 ierr = ISCreateGeneral(((PetscObject)snes)->comm,nloc_isact,idx_act,PETSC_OWN_POINTER,ISact);CHKERRQ(ierr); 941 942 ierr = VecRestoreArrayRead(X,&x);CHKERRQ(ierr); 943 ierr = VecRestoreArrayRead(Xl,&xl);CHKERRQ(ierr); 944 ierr = VecRestoreArrayRead(Xu,&xu);CHKERRQ(ierr); 945 ierr = VecRestoreArrayRead(F,&f);CHKERRQ(ierr); 946 PetscFunctionReturn(0); 947 } 948 949 #undef __FUNCT__ 950 #define __FUNCT__ "SNESVICreateIndexSets_RS" 951 PetscErrorCode SNESVICreateIndexSets_RS(SNES snes,Vec X,Vec F,IS* ISact,IS* ISinact) 952 { 953 PetscErrorCode ierr; 954 955 PetscFunctionBegin; 956 ierr = SNESVIGetActiveSetIS(snes,X,F,ISact);CHKERRQ(ierr); 957 ierr = ISComplement(*ISact,X->map->rstart,X->map->rend,ISinact);CHKERRQ(ierr); 958 PetscFunctionReturn(0); 959 } 960 961 /* Create active and inactive set vectors. The local size of this vector is set and petsc computes the global size */ 962 #undef __FUNCT__ 963 #define __FUNCT__ "SNESVICreateSubVectors" 964 PetscErrorCode SNESVICreateSubVectors(SNES snes,PetscInt n,Vec* newv) 965 { 966 PetscErrorCode ierr; 967 Vec v; 968 969 PetscFunctionBegin; 970 ierr = VecCreate(((PetscObject)snes)->comm,&v);CHKERRQ(ierr); 971 ierr = VecSetSizes(v,n,PETSC_DECIDE);CHKERRQ(ierr); 972 ierr = VecSetFromOptions(v);CHKERRQ(ierr); 973 *newv = v; 974 975 PetscFunctionReturn(0); 976 } 977 978 /* Resets the snes PC and KSP when the active set sizes change */ 979 #undef __FUNCT__ 980 #define __FUNCT__ "SNESVIResetPCandKSP" 981 PetscErrorCode SNESVIResetPCandKSP(SNES snes,Mat Amat,Mat Pmat) 982 { 983 PetscErrorCode ierr; 984 KSP snesksp; 985 986 PetscFunctionBegin; 987 ierr = SNESGetKSP(snes,&snesksp);CHKERRQ(ierr); 988 ierr = KSPReset(snesksp);CHKERRQ(ierr); 989 990 /* 991 KSP kspnew; 992 PC pcnew; 993 const MatSolverPackage stype; 994 995 996 ierr = KSPCreate(((PetscObject)snes)->comm,&kspnew);CHKERRQ(ierr); 997 kspnew->pc_side = snesksp->pc_side; 998 kspnew->rtol = snesksp->rtol; 999 kspnew->abstol = snesksp->abstol; 1000 kspnew->max_it = snesksp->max_it; 1001 ierr = KSPSetType(kspnew,((PetscObject)snesksp)->type_name);CHKERRQ(ierr); 1002 ierr = KSPGetPC(kspnew,&pcnew);CHKERRQ(ierr); 1003 ierr = PCSetType(kspnew->pc,((PetscObject)snesksp->pc)->type_name);CHKERRQ(ierr); 1004 ierr = PCSetOperators(kspnew->pc,Amat,Pmat,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr); 1005 ierr = PCFactorGetMatSolverPackage(snesksp->pc,&stype);CHKERRQ(ierr); 1006 ierr = PCFactorSetMatSolverPackage(kspnew->pc,stype);CHKERRQ(ierr); 1007 ierr = KSPDestroy(&snesksp);CHKERRQ(ierr); 1008 snes->ksp = kspnew; 1009 ierr = PetscLogObjectParent(snes,kspnew);CHKERRQ(ierr); 1010 ierr = KSPSetFromOptions(kspnew);CHKERRQ(ierr);*/ 1011 PetscFunctionReturn(0); 1012 } 1013 1014 1015 #undef __FUNCT__ 1016 #define __FUNCT__ "SNESVIComputeInactiveSetFnorm" 1017 PetscErrorCode SNESVIComputeInactiveSetFnorm(SNES snes,Vec F,Vec X,PetscReal *fnorm) 1018 { 1019 PetscErrorCode ierr; 1020 SNES_VI *vi = (SNES_VI*)snes->data; 1021 const PetscScalar *x,*xl,*xu,*f; 1022 PetscInt i,n; 1023 PetscReal rnorm; 1024 1025 PetscFunctionBegin; 1026 ierr = VecGetLocalSize(X,&n);CHKERRQ(ierr); 1027 ierr = VecGetArrayRead(vi->xl,&xl);CHKERRQ(ierr); 1028 ierr = VecGetArrayRead(vi->xu,&xu);CHKERRQ(ierr); 1029 ierr = VecGetArrayRead(X,&x);CHKERRQ(ierr); 1030 ierr = VecGetArrayRead(F,&f);CHKERRQ(ierr); 1031 rnorm = 0.0; 1032 for (i=0; i<n; i++) { 1033 if (((PetscRealPart(x[i]) > PetscRealPart(xl[i]) + 1.e-8 || (PetscRealPart(f[i]) < 0.0)) && ((PetscRealPart(x[i]) < PetscRealPart(xu[i]) - 1.e-8) || PetscRealPart(f[i]) > 0.0))) rnorm += PetscRealPart(PetscConj(f[i])*f[i]); 1034 } 1035 ierr = VecRestoreArrayRead(F,&f);CHKERRQ(ierr); 1036 ierr = VecRestoreArrayRead(vi->xl,&xl);CHKERRQ(ierr); 1037 ierr = VecRestoreArrayRead(vi->xu,&xu);CHKERRQ(ierr); 1038 ierr = VecRestoreArrayRead(X,&x);CHKERRQ(ierr); 1039 ierr = MPI_Allreduce(&rnorm,fnorm,1,MPIU_REAL,MPIU_SUM,((PetscObject)snes)->comm);CHKERRQ(ierr); 1040 *fnorm = sqrt(*fnorm); 1041 PetscFunctionReturn(0); 1042 } 1043 1044 /* Variational Inequality solver using reduce space method. No semismooth algorithm is 1045 implemented in this algorithm. It basically identifies the active constraints and does 1046 a linear solve on the other variables (those not associated with the active constraints). */ 1047 #undef __FUNCT__ 1048 #define __FUNCT__ "SNESSolveVI_RS" 1049 PetscErrorCode SNESSolveVI_RS(SNES snes) 1050 { 1051 SNES_VI *vi = (SNES_VI*)snes->data; 1052 PetscErrorCode ierr; 1053 PetscInt maxits,i,lits; 1054 PetscBool lssucceed; 1055 MatStructure flg = DIFFERENT_NONZERO_PATTERN; 1056 PetscReal fnorm,gnorm,xnorm=0,ynorm; 1057 Vec Y,X,F,G,W; 1058 KSPConvergedReason kspreason; 1059 1060 PetscFunctionBegin; 1061 snes->numFailures = 0; 1062 snes->numLinearSolveFailures = 0; 1063 snes->reason = SNES_CONVERGED_ITERATING; 1064 1065 maxits = snes->max_its; /* maximum number of iterations */ 1066 X = snes->vec_sol; /* solution vector */ 1067 F = snes->vec_func; /* residual vector */ 1068 Y = snes->work[0]; /* work vectors */ 1069 G = snes->work[1]; 1070 W = snes->work[2]; 1071 1072 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1073 snes->iter = 0; 1074 snes->norm = 0.0; 1075 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1076 1077 ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr); 1078 ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr); 1079 if (snes->domainerror) { 1080 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 1081 PetscFunctionReturn(0); 1082 } 1083 ierr = SNESVIComputeInactiveSetFnorm(snes,F,X,&fnorm);CHKERRQ(ierr); 1084 ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr); /* xnorm <- ||x|| */ 1085 ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr); 1086 if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1087 1088 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1089 snes->norm = fnorm; 1090 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1091 SNESLogConvHistory(snes,fnorm,0); 1092 ierr = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr); 1093 1094 /* set parameter for default relative tolerance convergence test */ 1095 snes->ttol = fnorm*snes->rtol; 1096 /* test convergence */ 1097 ierr = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1098 if (snes->reason) PetscFunctionReturn(0); 1099 1100 for (i=0; i<maxits; i++) { 1101 1102 IS IS_act,IS_inact; /* _act -> active set _inact -> inactive set */ 1103 IS IS_redact; /* redundant active set */ 1104 VecScatter scat_act,scat_inact; 1105 PetscInt nis_act,nis_inact; 1106 Vec Y_act,Y_inact,F_inact; 1107 Mat jac_inact_inact,prejac_inact_inact; 1108 IS keptrows; 1109 PetscBool isequal; 1110 1111 /* Call general purpose update function */ 1112 if (snes->ops->update) { 1113 ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr); 1114 } 1115 ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr); 1116 1117 /* Create active and inactive index sets */ 1118 1119 /*original 1120 ierr = SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&IS_inact);CHKERRQ(ierr); 1121 */ 1122 ierr = SNESVIGetActiveSetIS(snes,X,F,&IS_act);CHKERRQ(ierr); 1123 1124 if (vi->checkredundancy) { 1125 (*vi->checkredundancy)(snes,IS_act,&IS_redact,vi->ctxP);CHKERRQ(ierr); 1126 ierr = ISComplement(IS_redact,X->map->rstart,X->map->rend,&IS_inact);CHKERRQ(ierr); 1127 ierr = ISDestroy(&IS_redact);CHKERRQ(ierr); 1128 } else { 1129 ierr = ISComplement(IS_act,X->map->rstart,X->map->rend,&IS_inact);CHKERRQ(ierr); 1130 } 1131 1132 1133 /* Create inactive set submatrix */ 1134 ierr = MatGetSubMatrix(snes->jacobian,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);CHKERRQ(ierr); 1135 1136 ierr = MatFindNonzeroRows(jac_inact_inact,&keptrows);CHKERRQ(ierr); 1137 if (keptrows) { 1138 PetscInt cnt,*nrows,k; 1139 const PetscInt *krows,*inact; 1140 PetscInt rstart=jac_inact_inact->rmap->rstart; 1141 1142 ierr = MatDestroy(&jac_inact_inact);CHKERRQ(ierr); 1143 ierr = ISDestroy(&IS_act);CHKERRQ(ierr); 1144 1145 ierr = ISGetLocalSize(keptrows,&cnt);CHKERRQ(ierr); 1146 ierr = ISGetIndices(keptrows,&krows);CHKERRQ(ierr); 1147 ierr = ISGetIndices(IS_inact,&inact);CHKERRQ(ierr); 1148 ierr = PetscMalloc(cnt*sizeof(PetscInt),&nrows);CHKERRQ(ierr); 1149 for (k=0; k<cnt; k++) { 1150 nrows[k] = inact[krows[k]-rstart]; 1151 } 1152 ierr = ISRestoreIndices(keptrows,&krows);CHKERRQ(ierr); 1153 ierr = ISRestoreIndices(IS_inact,&inact);CHKERRQ(ierr); 1154 ierr = ISDestroy(&keptrows);CHKERRQ(ierr); 1155 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 1156 1157 ierr = ISCreateGeneral(PETSC_COMM_WORLD,cnt,nrows,PETSC_OWN_POINTER,&IS_inact);CHKERRQ(ierr); 1158 ierr = ISComplement(IS_inact,F->map->rstart,F->map->rend,&IS_act);CHKERRQ(ierr); 1159 ierr = MatGetSubMatrix(snes->jacobian,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);CHKERRQ(ierr); 1160 } 1161 ierr = DMSetVI(snes->dm,vi->xu,vi->xl,X,F,IS_inact);CHKERRQ(ierr); 1162 1163 /* Get sizes of active and inactive sets */ 1164 ierr = ISGetLocalSize(IS_act,&nis_act);CHKERRQ(ierr); 1165 ierr = ISGetLocalSize(IS_inact,&nis_inact);CHKERRQ(ierr); 1166 1167 /* Create active and inactive set vectors */ 1168 ierr = SNESVICreateSubVectors(snes,nis_inact,&F_inact);CHKERRQ(ierr); 1169 ierr = SNESVICreateSubVectors(snes,nis_act,&Y_act);CHKERRQ(ierr); 1170 ierr = SNESVICreateSubVectors(snes,nis_inact,&Y_inact);CHKERRQ(ierr); 1171 1172 /* Create scatter contexts */ 1173 ierr = VecScatterCreate(Y,IS_act,Y_act,PETSC_NULL,&scat_act);CHKERRQ(ierr); 1174 ierr = VecScatterCreate(Y,IS_inact,Y_inact,PETSC_NULL,&scat_inact);CHKERRQ(ierr); 1175 1176 /* Do a vec scatter to active and inactive set vectors */ 1177 ierr = VecScatterBegin(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 1178 ierr = VecScatterEnd(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 1179 1180 ierr = VecScatterBegin(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 1181 ierr = VecScatterEnd(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 1182 1183 ierr = VecScatterBegin(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 1184 ierr = VecScatterEnd(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 1185 1186 /* Active set direction = 0 */ 1187 ierr = VecSet(Y_act,0);CHKERRQ(ierr); 1188 if (snes->jacobian != snes->jacobian_pre) { 1189 ierr = MatGetSubMatrix(snes->jacobian_pre,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&prejac_inact_inact);CHKERRQ(ierr); 1190 } else prejac_inact_inact = jac_inact_inact; 1191 1192 ierr = ISEqual(vi->IS_inact_prev,IS_inact,&isequal);CHKERRQ(ierr); 1193 if (!isequal) { 1194 ierr = SNESVIResetPCandKSP(snes,jac_inact_inact,prejac_inact_inact);CHKERRQ(ierr); 1195 flg = DIFFERENT_NONZERO_PATTERN; 1196 } 1197 1198 /* ierr = ISView(IS_inact,0);CHKERRQ(ierr); */ 1199 /* ierr = ISView(IS_act,0);CHKERRQ(ierr);*/ 1200 /* ierr = MatView(snes->jacobian_pre,0); */ 1201 1202 ierr = KSPSetOperators(snes->ksp,jac_inact_inact,prejac_inact_inact,flg);CHKERRQ(ierr); 1203 ierr = KSPSetUp(snes->ksp);CHKERRQ(ierr); 1204 { 1205 PC pc; 1206 PetscBool flg; 1207 ierr = KSPGetPC(snes->ksp,&pc);CHKERRQ(ierr); 1208 ierr = PetscTypeCompare((PetscObject)pc,PCFIELDSPLIT,&flg);CHKERRQ(ierr); 1209 if (flg) { 1210 KSP *subksps; 1211 ierr = PCFieldSplitGetSubKSP(pc,PETSC_NULL,&subksps);CHKERRQ(ierr); 1212 ierr = KSPGetPC(subksps[0],&pc);CHKERRQ(ierr); 1213 ierr = PetscFree(subksps);CHKERRQ(ierr); 1214 ierr = PetscTypeCompare((PetscObject)pc,PCBJACOBI,&flg);CHKERRQ(ierr); 1215 if (flg) { 1216 PetscInt n,N = 101*101,j,cnts[3] = {0,0,0}; 1217 const PetscInt *ii; 1218 1219 ierr = ISGetSize(IS_inact,&n);CHKERRQ(ierr); 1220 ierr = ISGetIndices(IS_inact,&ii);CHKERRQ(ierr); 1221 for (j=0; j<n; j++) { 1222 if (ii[j] < N) cnts[0]++; 1223 else if (ii[j] < 2*N) cnts[1]++; 1224 else if (ii[j] < 3*N) cnts[2]++; 1225 } 1226 ierr = ISRestoreIndices(IS_inact,&ii);CHKERRQ(ierr); 1227 1228 ierr = PCBJacobiSetTotalBlocks(pc,3,cnts);CHKERRQ(ierr); 1229 } 1230 } 1231 } 1232 1233 ierr = SNES_KSPSolve(snes,snes->ksp,F_inact,Y_inact);CHKERRQ(ierr); 1234 ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr); 1235 if (kspreason < 0) { 1236 if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) { 1237 ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr); 1238 snes->reason = SNES_DIVERGED_LINEAR_SOLVE; 1239 break; 1240 } 1241 } 1242 1243 ierr = VecScatterBegin(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 1244 ierr = VecScatterEnd(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 1245 ierr = VecScatterBegin(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 1246 ierr = VecScatterEnd(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 1247 1248 ierr = VecDestroy(&F_inact);CHKERRQ(ierr); 1249 ierr = VecDestroy(&Y_act);CHKERRQ(ierr); 1250 ierr = VecDestroy(&Y_inact);CHKERRQ(ierr); 1251 ierr = VecScatterDestroy(&scat_act);CHKERRQ(ierr); 1252 ierr = VecScatterDestroy(&scat_inact);CHKERRQ(ierr); 1253 ierr = ISDestroy(&IS_act);CHKERRQ(ierr); 1254 if (!isequal) { 1255 ierr = ISDestroy(&vi->IS_inact_prev);CHKERRQ(ierr); 1256 ierr = ISDuplicate(IS_inact,&vi->IS_inact_prev);CHKERRQ(ierr); 1257 } 1258 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 1259 ierr = MatDestroy(&jac_inact_inact);CHKERRQ(ierr); 1260 if (snes->jacobian != snes->jacobian_pre) { 1261 ierr = MatDestroy(&prejac_inact_inact);CHKERRQ(ierr); 1262 } 1263 ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr); 1264 snes->linear_its += lits; 1265 ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr); 1266 /* 1267 if (vi->precheckstep) { 1268 PetscBool changed_y = PETSC_FALSE; 1269 ierr = (*vi->precheckstep)(snes,X,Y,vi->precheck,&changed_y);CHKERRQ(ierr); 1270 } 1271 1272 if (PetscLogPrintInfo){ 1273 ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr); 1274 } 1275 */ 1276 /* Compute a (scaled) negative update in the line search routine: 1277 Y <- X - lambda*Y 1278 and evaluate G = function(Y) (depends on the line search). 1279 */ 1280 ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr); 1281 ynorm = 1; gnorm = fnorm; 1282 ierr = (*vi->LineSearch)(snes,vi->lsP,X,F,G,Y,W,fnorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr); 1283 ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",fnorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr); 1284 if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break; 1285 if (snes->domainerror) { 1286 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 1287 ierr = DMDestroyVI(snes->dm);CHKERRQ(ierr); 1288 PetscFunctionReturn(0); 1289 } 1290 if (!lssucceed) { 1291 if (++snes->numFailures >= snes->maxFailures) { 1292 PetscBool ismin; 1293 snes->reason = SNES_DIVERGED_LINE_SEARCH; 1294 ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr); 1295 if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN; 1296 break; 1297 } 1298 } 1299 /* Update function and solution vectors */ 1300 fnorm = gnorm; 1301 ierr = VecCopy(G,F);CHKERRQ(ierr); 1302 ierr = VecCopy(W,X);CHKERRQ(ierr); 1303 /* Monitor convergence */ 1304 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1305 snes->iter = i+1; 1306 snes->norm = fnorm; 1307 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1308 SNESLogConvHistory(snes,snes->norm,lits); 1309 ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr); 1310 /* Test for convergence, xnorm = || X || */ 1311 if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); } 1312 ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1313 if (snes->reason) break; 1314 } 1315 ierr = DMDestroyVI(snes->dm);CHKERRQ(ierr); 1316 if (i == maxits) { 1317 ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr); 1318 if(!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT; 1319 } 1320 PetscFunctionReturn(0); 1321 } 1322 1323 #undef __FUNCT__ 1324 #define __FUNCT__ "SNESVISetRedundancyCheck" 1325 PetscErrorCode SNESVISetRedundancyCheck(SNES snes,PetscErrorCode (*func)(SNES,IS,IS*,void*),void *ctx) 1326 { 1327 SNES_VI *vi = (SNES_VI*)snes->data; 1328 1329 PetscFunctionBegin; 1330 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 1331 vi->checkredundancy = func; 1332 vi->ctxP = ctx; 1333 PetscFunctionReturn(0); 1334 } 1335 1336 #if defined(PETSC_HAVE_MATLAB_ENGINE) 1337 #include <engine.h> 1338 #include <mex.h> 1339 typedef struct {char *funcname; mxArray *ctx;} SNESMatlabContext; 1340 1341 #undef __FUNCT__ 1342 #define __FUNCT__ "SNESVIRedundancyCheck_Matlab" 1343 PetscErrorCode SNESVIRedundancyCheck_Matlab(SNES snes,IS is_act,IS* is_redact,void* ctx) 1344 { 1345 PetscErrorCode ierr; 1346 SNESMatlabContext *sctx = (SNESMatlabContext*)ctx; 1347 int nlhs = 1, nrhs = 5; 1348 mxArray *plhs[1], *prhs[5]; 1349 long long int l1 = 0, l2 = 0, ls = 0; 1350 PetscInt *indices=PETSC_NULL; 1351 1352 PetscFunctionBegin; 1353 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 1354 PetscValidHeaderSpecific(is_act,IS_CLASSID,2); 1355 PetscValidPointer(is_redact,3); 1356 PetscCheckSameComm(snes,1,is_act,2); 1357 1358 /* Create IS for reduced active set of size 0, its size and indices will 1359 bet set by the Matlab function */ 1360 ierr = ISCreateGeneral(((PetscObject)snes)->comm,0,indices,PETSC_OWN_POINTER,is_redact);CHKERRQ(ierr); 1361 /* call Matlab function in ctx */ 1362 ierr = PetscMemcpy(&ls,&snes,sizeof(snes));CHKERRQ(ierr); 1363 ierr = PetscMemcpy(&l1,&is_act,sizeof(is_act));CHKERRQ(ierr); 1364 ierr = PetscMemcpy(&l2,is_redact,sizeof(is_act));CHKERRQ(ierr); 1365 prhs[0] = mxCreateDoubleScalar((double)ls); 1366 prhs[1] = mxCreateDoubleScalar((double)l1); 1367 prhs[2] = mxCreateDoubleScalar((double)l2); 1368 prhs[3] = mxCreateString(sctx->funcname); 1369 prhs[4] = sctx->ctx; 1370 ierr = mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESVIRedundancyCheckInternal");CHKERRQ(ierr); 1371 ierr = mxGetScalar(plhs[0]);CHKERRQ(ierr); 1372 mxDestroyArray(prhs[0]); 1373 mxDestroyArray(prhs[1]); 1374 mxDestroyArray(prhs[2]); 1375 mxDestroyArray(prhs[3]); 1376 mxDestroyArray(plhs[0]); 1377 PetscFunctionReturn(0); 1378 } 1379 1380 #undef __FUNCT__ 1381 #define __FUNCT__ "SNESVISetRedundancyCheckMatlab" 1382 PetscErrorCode SNESVISetRedundancyCheckMatlab(SNES snes,const char* func,mxArray* ctx) 1383 { 1384 PetscErrorCode ierr; 1385 SNESMatlabContext *sctx; 1386 1387 PetscFunctionBegin; 1388 /* currently sctx is memory bleed */ 1389 ierr = PetscMalloc(sizeof(SNESMatlabContext),&sctx);CHKERRQ(ierr); 1390 ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr); 1391 sctx->ctx = mxDuplicateArray(ctx); 1392 ierr = SNESVISetRedundancyCheck(snes,SNESVIRedundancyCheck_Matlab,sctx);CHKERRQ(ierr); 1393 PetscFunctionReturn(0); 1394 } 1395 1396 #endif 1397 1398 1399 /* Variational Inequality solver using augmented space method. It does the opposite of the 1400 reduced space method i.e. it identifies the active set variables and instead of discarding 1401 them it augments the original system by introducing additional equality 1402 constraint equations for active set variables. The user can optionally provide an IS for 1403 a subset of 'redundant' active set variables which will treated as free variables. 1404 Specific implementation for Allen-Cahn problem 1405 */ 1406 #undef __FUNCT__ 1407 #define __FUNCT__ "SNESSolveVI_RSAUG" 1408 PetscErrorCode SNESSolveVI_RSAUG(SNES snes) 1409 { 1410 SNES_VI *vi = (SNES_VI*)snes->data; 1411 PetscErrorCode ierr; 1412 PetscInt maxits,i,lits; 1413 PetscBool lssucceed; 1414 MatStructure flg = DIFFERENT_NONZERO_PATTERN; 1415 PetscReal fnorm,gnorm,xnorm=0,ynorm; 1416 Vec Y,X,F,G,W; 1417 KSPConvergedReason kspreason; 1418 1419 PetscFunctionBegin; 1420 snes->numFailures = 0; 1421 snes->numLinearSolveFailures = 0; 1422 snes->reason = SNES_CONVERGED_ITERATING; 1423 1424 maxits = snes->max_its; /* maximum number of iterations */ 1425 X = snes->vec_sol; /* solution vector */ 1426 F = snes->vec_func; /* residual vector */ 1427 Y = snes->work[0]; /* work vectors */ 1428 G = snes->work[1]; 1429 W = snes->work[2]; 1430 1431 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1432 snes->iter = 0; 1433 snes->norm = 0.0; 1434 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1435 1436 ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr); 1437 ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr); 1438 if (snes->domainerror) { 1439 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 1440 PetscFunctionReturn(0); 1441 } 1442 ierr = SNESVIComputeInactiveSetFnorm(snes,F,X,&fnorm);CHKERRQ(ierr); 1443 ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr); /* xnorm <- ||x|| */ 1444 ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr); 1445 if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1446 1447 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1448 snes->norm = fnorm; 1449 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1450 SNESLogConvHistory(snes,fnorm,0); 1451 ierr = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr); 1452 1453 /* set parameter for default relative tolerance convergence test */ 1454 snes->ttol = fnorm*snes->rtol; 1455 /* test convergence */ 1456 ierr = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1457 if (snes->reason) PetscFunctionReturn(0); 1458 1459 for (i=0; i<maxits; i++) { 1460 IS IS_act,IS_inact; /* _act -> active set _inact -> inactive set */ 1461 IS IS_redact; /* redundant active set */ 1462 Mat J_aug,Jpre_aug; 1463 Vec F_aug,Y_aug; 1464 PetscInt nis_redact,nis_act; 1465 const PetscInt *idx_redact,*idx_act; 1466 PetscInt k; 1467 PetscInt *idx_actkept=PETSC_NULL,nkept=0; /* list of kept active set */ 1468 PetscScalar *f,*f2; 1469 PetscBool isequal; 1470 PetscInt i1=0,j1=0; 1471 1472 /* Call general purpose update function */ 1473 if (snes->ops->update) { 1474 ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr); 1475 } 1476 ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr); 1477 1478 /* Create active and inactive index sets */ 1479 ierr = SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&IS_inact);CHKERRQ(ierr); 1480 1481 /* Get local active set size */ 1482 ierr = ISGetLocalSize(IS_act,&nis_act);CHKERRQ(ierr); 1483 if (nis_act) { 1484 ierr = ISGetIndices(IS_act,&idx_act);CHKERRQ(ierr); 1485 IS_redact = PETSC_NULL; 1486 if(vi->checkredundancy) { 1487 (*vi->checkredundancy)(snes,IS_act,&IS_redact,vi->ctxP); 1488 } 1489 1490 if(!IS_redact) { 1491 /* User called checkredundancy function but didn't create IS_redact because 1492 there were no redundant active set variables */ 1493 /* Copy over all active set indices to the list */ 1494 ierr = PetscMalloc(nis_act*sizeof(PetscInt),&idx_actkept);CHKERRQ(ierr); 1495 for(k=0;k < nis_act;k++) idx_actkept[k] = idx_act[k]; 1496 nkept = nis_act; 1497 } else { 1498 ierr = ISGetLocalSize(IS_redact,&nis_redact);CHKERRQ(ierr); 1499 ierr = PetscMalloc((nis_act-nis_redact)*sizeof(PetscInt),&idx_actkept);CHKERRQ(ierr); 1500 1501 /* Create reduced active set list */ 1502 ierr = ISGetIndices(IS_act,&idx_act);CHKERRQ(ierr); 1503 ierr = ISGetIndices(IS_redact,&idx_redact);CHKERRQ(ierr); 1504 j1 = 0;nkept = 0; 1505 for(k=0;k<nis_act;k++) { 1506 if(j1 < nis_redact && idx_act[k] == idx_redact[j1]) j1++; 1507 else idx_actkept[nkept++] = idx_act[k]; 1508 } 1509 ierr = ISRestoreIndices(IS_act,&idx_act);CHKERRQ(ierr); 1510 ierr = ISRestoreIndices(IS_redact,&idx_redact);CHKERRQ(ierr); 1511 1512 ierr = ISDestroy(&IS_redact);CHKERRQ(ierr); 1513 } 1514 1515 /* Create augmented F and Y */ 1516 ierr = VecCreate(((PetscObject)snes)->comm,&F_aug);CHKERRQ(ierr); 1517 ierr = VecSetSizes(F_aug,F->map->n+nkept,PETSC_DECIDE);CHKERRQ(ierr); 1518 ierr = VecSetFromOptions(F_aug);CHKERRQ(ierr); 1519 ierr = VecDuplicate(F_aug,&Y_aug);CHKERRQ(ierr); 1520 1521 /* Copy over F to F_aug in the first n locations */ 1522 ierr = VecGetArray(F,&f);CHKERRQ(ierr); 1523 ierr = VecGetArray(F_aug,&f2);CHKERRQ(ierr); 1524 ierr = PetscMemcpy(f2,f,F->map->n*sizeof(PetscScalar));CHKERRQ(ierr); 1525 ierr = VecRestoreArray(F,&f);CHKERRQ(ierr); 1526 ierr = VecRestoreArray(F_aug,&f2);CHKERRQ(ierr); 1527 1528 /* Create the augmented jacobian matrix */ 1529 ierr = MatCreate(((PetscObject)snes)->comm,&J_aug);CHKERRQ(ierr); 1530 ierr = MatSetSizes(J_aug,X->map->n+nkept,X->map->n+nkept,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr); 1531 ierr = MatSetFromOptions(J_aug);CHKERRQ(ierr); 1532 1533 1534 { /* local vars */ 1535 /* Preallocate augmented matrix and set values in it...Doing only sequential case first*/ 1536 PetscInt ncols; 1537 const PetscInt *cols; 1538 const PetscScalar *vals; 1539 PetscScalar value[2]; 1540 PetscInt row,col[2]; 1541 PetscInt *d_nnz; 1542 value[0] = 1.0; value[1] = 0.0; 1543 ierr = PetscMalloc((X->map->n+nkept)*sizeof(PetscInt),&d_nnz);CHKERRQ(ierr); 1544 ierr = PetscMemzero(d_nnz,(X->map->n+nkept)*sizeof(PetscInt));CHKERRQ(ierr); 1545 for(row=0;row<snes->jacobian->rmap->n;row++) { 1546 ierr = MatGetRow(snes->jacobian,row,&ncols,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr); 1547 d_nnz[row] += ncols; 1548 ierr = MatRestoreRow(snes->jacobian,row,&ncols,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr); 1549 } 1550 1551 for(k=0;k<nkept;k++) { 1552 d_nnz[idx_actkept[k]] += 1; 1553 d_nnz[snes->jacobian->rmap->n+k] += 2; 1554 } 1555 ierr = MatSeqAIJSetPreallocation(J_aug,PETSC_NULL,d_nnz);CHKERRQ(ierr); 1556 1557 ierr = PetscFree(d_nnz);CHKERRQ(ierr); 1558 1559 /* Set the original jacobian matrix in J_aug */ 1560 for(row=0;row<snes->jacobian->rmap->n;row++) { 1561 ierr = MatGetRow(snes->jacobian,row,&ncols,&cols,&vals);CHKERRQ(ierr); 1562 ierr = MatSetValues(J_aug,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr); 1563 ierr = MatRestoreRow(snes->jacobian,row,&ncols,&cols,&vals);CHKERRQ(ierr); 1564 } 1565 /* Add the augmented part */ 1566 for(k=0;k<nkept;k++) { 1567 row = snes->jacobian->rmap->n+k; 1568 col[0] = idx_actkept[k]; col[1] = snes->jacobian->rmap->n+k; 1569 ierr = MatSetValues(J_aug,1,&row,1,col,value,INSERT_VALUES);CHKERRQ(ierr); 1570 ierr = MatSetValues(J_aug,1,&col[0],1,&row,&value[0],INSERT_VALUES);CHKERRQ(ierr); 1571 } 1572 ierr = MatAssemblyBegin(J_aug,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 1573 ierr = MatAssemblyEnd(J_aug,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 1574 /* Only considering prejac = jac for now */ 1575 Jpre_aug = J_aug; 1576 } /* local vars*/ 1577 ierr = ISRestoreIndices(IS_act,&idx_act);CHKERRQ(ierr); 1578 ierr = ISDestroy(&IS_act);CHKERRQ(ierr); 1579 } else { 1580 F_aug = F; J_aug = snes->jacobian; Y_aug = Y; Jpre_aug = snes->jacobian_pre; 1581 } 1582 1583 ierr = ISEqual(vi->IS_inact_prev,IS_inact,&isequal);CHKERRQ(ierr); 1584 if (!isequal) { 1585 ierr = SNESVIResetPCandKSP(snes,J_aug,Jpre_aug);CHKERRQ(ierr); 1586 } 1587 ierr = KSPSetOperators(snes->ksp,J_aug,Jpre_aug,flg);CHKERRQ(ierr); 1588 ierr = KSPSetUp(snes->ksp);CHKERRQ(ierr); 1589 /* { 1590 PC pc; 1591 PetscBool flg; 1592 ierr = KSPGetPC(snes->ksp,&pc);CHKERRQ(ierr); 1593 ierr = PetscTypeCompare((PetscObject)pc,PCFIELDSPLIT,&flg);CHKERRQ(ierr); 1594 if (flg) { 1595 KSP *subksps; 1596 ierr = PCFieldSplitGetSubKSP(pc,PETSC_NULL,&subksps);CHKERRQ(ierr); 1597 ierr = KSPGetPC(subksps[0],&pc);CHKERRQ(ierr); 1598 ierr = PetscFree(subksps);CHKERRQ(ierr); 1599 ierr = PetscTypeCompare((PetscObject)pc,PCBJACOBI,&flg);CHKERRQ(ierr); 1600 if (flg) { 1601 PetscInt n,N = 101*101,j,cnts[3] = {0,0,0}; 1602 const PetscInt *ii; 1603 1604 ierr = ISGetSize(IS_inact,&n);CHKERRQ(ierr); 1605 ierr = ISGetIndices(IS_inact,&ii);CHKERRQ(ierr); 1606 for (j=0; j<n; j++) { 1607 if (ii[j] < N) cnts[0]++; 1608 else if (ii[j] < 2*N) cnts[1]++; 1609 else if (ii[j] < 3*N) cnts[2]++; 1610 } 1611 ierr = ISRestoreIndices(IS_inact,&ii);CHKERRQ(ierr); 1612 1613 ierr = PCBJacobiSetTotalBlocks(pc,3,cnts);CHKERRQ(ierr); 1614 } 1615 } 1616 } 1617 */ 1618 ierr = SNES_KSPSolve(snes,snes->ksp,F_aug,Y_aug);CHKERRQ(ierr); 1619 ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr); 1620 if (kspreason < 0) { 1621 if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) { 1622 ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr); 1623 snes->reason = SNES_DIVERGED_LINEAR_SOLVE; 1624 break; 1625 } 1626 } 1627 1628 if(nis_act) { 1629 PetscScalar *y1,*y2; 1630 ierr = VecGetArray(Y,&y1);CHKERRQ(ierr); 1631 ierr = VecGetArray(Y_aug,&y2);CHKERRQ(ierr); 1632 /* Copy over inactive Y_aug to Y */ 1633 j1 = 0; 1634 for(i1=Y->map->rstart;i1 < Y->map->rend;i1++) { 1635 if(j1 < nkept && idx_actkept[j1] == i1) j1++; 1636 else y1[i1-Y->map->rstart] = y2[i1-Y->map->rstart]; 1637 } 1638 ierr = VecRestoreArray(Y,&y1);CHKERRQ(ierr); 1639 ierr = VecRestoreArray(Y_aug,&y2);CHKERRQ(ierr); 1640 1641 ierr = VecDestroy(&F_aug);CHKERRQ(ierr); 1642 ierr = VecDestroy(&Y_aug);CHKERRQ(ierr); 1643 ierr = MatDestroy(&J_aug);CHKERRQ(ierr); 1644 ierr = PetscFree(idx_actkept);CHKERRQ(ierr); 1645 } 1646 1647 if (!isequal) { 1648 ierr = ISDestroy(&vi->IS_inact_prev);CHKERRQ(ierr); 1649 ierr = ISDuplicate(IS_inact,&vi->IS_inact_prev);CHKERRQ(ierr); 1650 } 1651 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 1652 1653 ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr); 1654 snes->linear_its += lits; 1655 ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr); 1656 /* 1657 if (vi->precheckstep) { 1658 PetscBool changed_y = PETSC_FALSE; 1659 ierr = (*vi->precheckstep)(snes,X,Y,vi->precheck,&changed_y);CHKERRQ(ierr); 1660 } 1661 1662 if (PetscLogPrintInfo){ 1663 ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr); 1664 } 1665 */ 1666 /* Compute a (scaled) negative update in the line search routine: 1667 Y <- X - lambda*Y 1668 and evaluate G = function(Y) (depends on the line search). 1669 */ 1670 ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr); 1671 ynorm = 1; gnorm = fnorm; 1672 ierr = (*vi->LineSearch)(snes,vi->lsP,X,F,G,Y,W,fnorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr); 1673 ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",fnorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr); 1674 if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break; 1675 if (snes->domainerror) { 1676 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 1677 PetscFunctionReturn(0); 1678 } 1679 if (!lssucceed) { 1680 if (++snes->numFailures >= snes->maxFailures) { 1681 PetscBool ismin; 1682 snes->reason = SNES_DIVERGED_LINE_SEARCH; 1683 ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr); 1684 if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN; 1685 break; 1686 } 1687 } 1688 /* Update function and solution vectors */ 1689 fnorm = gnorm; 1690 ierr = VecCopy(G,F);CHKERRQ(ierr); 1691 ierr = VecCopy(W,X);CHKERRQ(ierr); 1692 /* Monitor convergence */ 1693 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1694 snes->iter = i+1; 1695 snes->norm = fnorm; 1696 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1697 SNESLogConvHistory(snes,snes->norm,lits); 1698 ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr); 1699 /* Test for convergence, xnorm = || X || */ 1700 if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); } 1701 ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1702 if (snes->reason) break; 1703 } 1704 if (i == maxits) { 1705 ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr); 1706 if(!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT; 1707 } 1708 PetscFunctionReturn(0); 1709 } 1710 1711 /* -------------------------------------------------------------------------- */ 1712 /* 1713 SNESSetUp_VI - Sets up the internal data structures for the later use 1714 of the SNESVI nonlinear solver. 1715 1716 Input Parameter: 1717 . snes - the SNES context 1718 . x - the solution vector 1719 1720 Application Interface Routine: SNESSetUp() 1721 1722 Notes: 1723 For basic use of the SNES solvers, the user need not explicitly call 1724 SNESSetUp(), since these actions will automatically occur during 1725 the call to SNESSolve(). 1726 */ 1727 #undef __FUNCT__ 1728 #define __FUNCT__ "SNESSetUp_VI" 1729 PetscErrorCode SNESSetUp_VI(SNES snes) 1730 { 1731 PetscErrorCode ierr; 1732 SNES_VI *vi = (SNES_VI*) snes->data; 1733 PetscInt i_start[3],i_end[3]; 1734 1735 PetscFunctionBegin; 1736 1737 ierr = SNESDefaultGetWork(snes,3);CHKERRQ(ierr); 1738 1739 if (vi->computevariablebounds) { 1740 if (!vi->xl) {ierr = VecDuplicate(snes->vec_sol,&vi->xl);CHKERRQ(ierr);} 1741 if (!vi->xu) {ierr = VecDuplicate(snes->vec_sol,&vi->xu);CHKERRQ(ierr);} 1742 ierr = (*vi->computevariablebounds)(snes,vi->xl,vi->xu);CHKERRQ(ierr); 1743 } else if (!vi->xl && !vi->xu) { 1744 /* If the lower and upper bound on variables are not set, set it to -Inf and Inf */ 1745 ierr = VecDuplicate(snes->vec_sol, &vi->xl);CHKERRQ(ierr); 1746 ierr = VecSet(vi->xl,SNES_VI_NINF);CHKERRQ(ierr); 1747 ierr = VecDuplicate(snes->vec_sol, &vi->xu);CHKERRQ(ierr); 1748 ierr = VecSet(vi->xu,SNES_VI_INF);CHKERRQ(ierr); 1749 } else { 1750 /* Check if lower bound, upper bound and solution vector distribution across the processors is identical */ 1751 ierr = VecGetOwnershipRange(snes->vec_sol,i_start,i_end);CHKERRQ(ierr); 1752 ierr = VecGetOwnershipRange(vi->xl,i_start+1,i_end+1);CHKERRQ(ierr); 1753 ierr = VecGetOwnershipRange(vi->xu,i_start+2,i_end+2);CHKERRQ(ierr); 1754 if ((i_start[0] != i_start[1]) || (i_start[0] != i_start[2]) || (i_end[0] != i_end[1]) || (i_end[0] != i_end[2])) 1755 SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Distribution of lower bound, upper bound and the solution vector should be identical across all the processors."); 1756 } 1757 if (snes->ops->solve != SNESSolveVI_SS) { 1758 /* Set up previous active index set for the first snes solve 1759 vi->IS_inact_prev = 0,1,2,....N */ 1760 PetscInt *indices; 1761 PetscInt i,n,rstart,rend; 1762 1763 ierr = VecGetOwnershipRange(snes->vec_sol,&rstart,&rend);CHKERRQ(ierr); 1764 ierr = VecGetLocalSize(snes->vec_sol,&n);CHKERRQ(ierr); 1765 ierr = PetscMalloc(n*sizeof(PetscInt),&indices);CHKERRQ(ierr); 1766 for(i=0;i < n; i++) indices[i] = rstart + i; 1767 ierr = ISCreateGeneral(((PetscObject)snes)->comm,n,indices,PETSC_OWN_POINTER,&vi->IS_inact_prev); 1768 } 1769 1770 if (snes->ops->solve == SNESSolveVI_SS) { 1771 ierr = VecDuplicate(snes->vec_sol, &vi->dpsi);CHKERRQ(ierr); 1772 ierr = VecDuplicate(snes->vec_sol, &vi->phi);CHKERRQ(ierr); 1773 ierr = VecDuplicate(snes->vec_sol, &vi->Da);CHKERRQ(ierr); 1774 ierr = VecDuplicate(snes->vec_sol, &vi->Db);CHKERRQ(ierr); 1775 ierr = VecDuplicate(snes->vec_sol, &vi->z);CHKERRQ(ierr); 1776 ierr = VecDuplicate(snes->vec_sol, &vi->t);CHKERRQ(ierr); 1777 } 1778 PetscFunctionReturn(0); 1779 } 1780 /* -------------------------------------------------------------------------- */ 1781 #undef __FUNCT__ 1782 #define __FUNCT__ "SNESReset_VI" 1783 PetscErrorCode SNESReset_VI(SNES snes) 1784 { 1785 SNES_VI *vi = (SNES_VI*) snes->data; 1786 PetscErrorCode ierr; 1787 1788 PetscFunctionBegin; 1789 ierr = VecDestroy(&vi->xl);CHKERRQ(ierr); 1790 ierr = VecDestroy(&vi->xu);CHKERRQ(ierr); 1791 if (snes->ops->solve != SNESSolveVI_SS) { 1792 ierr = ISDestroy(&vi->IS_inact_prev);CHKERRQ(ierr); 1793 } 1794 PetscFunctionReturn(0); 1795 } 1796 1797 /* 1798 SNESDestroy_VI - Destroys the private SNES_VI context that was created 1799 with SNESCreate_VI(). 1800 1801 Input Parameter: 1802 . snes - the SNES context 1803 1804 Application Interface Routine: SNESDestroy() 1805 */ 1806 #undef __FUNCT__ 1807 #define __FUNCT__ "SNESDestroy_VI" 1808 PetscErrorCode SNESDestroy_VI(SNES snes) 1809 { 1810 SNES_VI *vi = (SNES_VI*) snes->data; 1811 PetscErrorCode ierr; 1812 1813 PetscFunctionBegin; 1814 1815 if (snes->ops->solve == SNESSolveVI_SS) { 1816 /* clear vectors */ 1817 ierr = VecDestroy(&vi->dpsi);CHKERRQ(ierr); 1818 ierr = VecDestroy(&vi->phi);CHKERRQ(ierr); 1819 ierr = VecDestroy(&vi->Da);CHKERRQ(ierr); 1820 ierr = VecDestroy(&vi->Db);CHKERRQ(ierr); 1821 ierr = VecDestroy(&vi->z);CHKERRQ(ierr); 1822 ierr = VecDestroy(&vi->t);CHKERRQ(ierr); 1823 } 1824 1825 ierr = PetscViewerDestroy(&vi->lsmonitor);CHKERRQ(ierr); 1826 ierr = PetscFree(snes->data);CHKERRQ(ierr); 1827 1828 /* clear composed functions */ 1829 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSet_C","",PETSC_NULL);CHKERRQ(ierr); 1830 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSetMonitor_C","",PETSC_NULL);CHKERRQ(ierr); 1831 PetscFunctionReturn(0); 1832 } 1833 1834 /* -------------------------------------------------------------------------- */ 1835 #undef __FUNCT__ 1836 #define __FUNCT__ "SNESLineSearchNo_VI" 1837 1838 /* 1839 This routine does not actually do a line search but it takes a full newton 1840 step while ensuring that the new iterates remain within the constraints. 1841 1842 */ 1843 PetscErrorCode SNESLineSearchNo_VI(SNES snes,void *lsctx,Vec x,Vec f,Vec g,Vec y,Vec w,PetscReal fnorm,PetscReal xnorm,PetscReal *ynorm,PetscReal *gnorm,PetscBool *flag) 1844 { 1845 PetscErrorCode ierr; 1846 SNES_VI *vi = (SNES_VI*)snes->data; 1847 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1848 1849 PetscFunctionBegin; 1850 *flag = PETSC_TRUE; 1851 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1852 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); /* ynorm = || y || */ 1853 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1854 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1855 if (vi->postcheckstep) { 1856 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1857 } 1858 if (changed_y) { 1859 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1860 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1861 } 1862 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1863 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1864 if (!snes->domainerror) { 1865 if (snes->ops->solve != SNESSolveVI_SS) { 1866 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1867 } else { 1868 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); /* gnorm = || g || */ 1869 } 1870 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1871 } 1872 if (vi->lsmonitor) { 1873 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 1874 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1875 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 1876 } 1877 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1878 PetscFunctionReturn(0); 1879 } 1880 1881 /* -------------------------------------------------------------------------- */ 1882 #undef __FUNCT__ 1883 #define __FUNCT__ "SNESLineSearchNoNorms_VI" 1884 1885 /* 1886 This routine is a copy of SNESLineSearchNoNorms in snes/impls/ls/ls.c 1887 */ 1888 PetscErrorCode SNESLineSearchNoNorms_VI(SNES snes,void *lsctx,Vec x,Vec f,Vec g,Vec y,Vec w,PetscReal fnorm,PetscReal xnorm,PetscReal *ynorm,PetscReal *gnorm,PetscBool *flag) 1889 { 1890 PetscErrorCode ierr; 1891 SNES_VI *vi = (SNES_VI*)snes->data; 1892 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1893 1894 PetscFunctionBegin; 1895 *flag = PETSC_TRUE; 1896 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1897 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1898 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1899 if (vi->postcheckstep) { 1900 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1901 } 1902 if (changed_y) { 1903 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1904 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1905 } 1906 1907 /* don't evaluate function the last time through */ 1908 if (snes->iter < snes->max_its-1) { 1909 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1910 } 1911 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1912 PetscFunctionReturn(0); 1913 } 1914 1915 /* -------------------------------------------------------------------------- */ 1916 #undef __FUNCT__ 1917 #define __FUNCT__ "SNESLineSearchCubic_VI" 1918 /* 1919 This routine implements a cubic line search while doing a projection on the variable bounds 1920 */ 1921 PetscErrorCode SNESLineSearchCubic_VI(SNES snes,void *lsctx,Vec x,Vec f,Vec g,Vec y,Vec w,PetscReal fnorm,PetscReal xnorm,PetscReal *ynorm,PetscReal *gnorm,PetscBool *flag) 1922 { 1923 PetscReal initslope,lambdaprev,gnormprev,a,b,d,t1,t2,rellength; 1924 PetscReal minlambda,lambda,lambdatemp; 1925 #if defined(PETSC_USE_COMPLEX) 1926 PetscScalar cinitslope; 1927 #endif 1928 PetscErrorCode ierr; 1929 PetscInt count; 1930 SNES_VI *vi = (SNES_VI*)snes->data; 1931 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1932 MPI_Comm comm; 1933 1934 PetscFunctionBegin; 1935 ierr = PetscObjectGetComm((PetscObject)snes,&comm);CHKERRQ(ierr); 1936 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1937 *flag = PETSC_TRUE; 1938 1939 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); 1940 if (*ynorm == 0.0) { 1941 if (vi->lsmonitor) { 1942 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 1943 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line search: Initial direction and size is 0\n");CHKERRQ(ierr); 1944 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 1945 } 1946 *gnorm = fnorm; 1947 ierr = VecCopy(x,w);CHKERRQ(ierr); 1948 ierr = VecCopy(f,g);CHKERRQ(ierr); 1949 *flag = PETSC_FALSE; 1950 goto theend1; 1951 } 1952 if (*ynorm > vi->maxstep) { /* Step too big, so scale back */ 1953 if (vi->lsmonitor) { 1954 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 1955 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line search: Scaling step by %G old ynorm %G\n",vi->maxstep/(*ynorm),*ynorm);CHKERRQ(ierr); 1956 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 1957 } 1958 ierr = VecScale(y,vi->maxstep/(*ynorm));CHKERRQ(ierr); 1959 *ynorm = vi->maxstep; 1960 } 1961 ierr = VecMaxPointwiseDivide(y,x,&rellength);CHKERRQ(ierr); 1962 minlambda = vi->minlambda/rellength; 1963 ierr = MatMult(snes->jacobian,y,w);CHKERRQ(ierr); 1964 #if defined(PETSC_USE_COMPLEX) 1965 ierr = VecDot(f,w,&cinitslope);CHKERRQ(ierr); 1966 initslope = PetscRealPart(cinitslope); 1967 #else 1968 ierr = VecDot(f,w,&initslope);CHKERRQ(ierr); 1969 #endif 1970 if (initslope > 0.0) initslope = -initslope; 1971 if (initslope == 0.0) initslope = -1.0; 1972 1973 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1974 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1975 if (snes->nfuncs >= snes->max_funcs) { 1976 ierr = PetscInfo(snes,"Exceeded maximum function evaluations, while checking full step length!\n");CHKERRQ(ierr); 1977 *flag = PETSC_FALSE; 1978 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1979 goto theend1; 1980 } 1981 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1982 if (snes->ops->solve != SNESSolveVI_SS) { 1983 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1984 } else { 1985 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1986 } 1987 if (snes->domainerror) { 1988 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1989 PetscFunctionReturn(0); 1990 } 1991 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1992 ierr = PetscInfo2(snes,"Initial fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1993 if (.5*(*gnorm)*(*gnorm) <= .5*fnorm*fnorm + vi->alpha*initslope) { /* Sufficient reduction */ 1994 if (vi->lsmonitor) { 1995 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 1996 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1997 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 1998 } 1999 goto theend1; 2000 } 2001 2002 /* Fit points with quadratic */ 2003 lambda = 1.0; 2004 lambdatemp = -initslope/((*gnorm)*(*gnorm) - fnorm*fnorm - 2.0*initslope); 2005 lambdaprev = lambda; 2006 gnormprev = *gnorm; 2007 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 2008 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 2009 else lambda = lambdatemp; 2010 2011 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 2012 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 2013 if (snes->nfuncs >= snes->max_funcs) { 2014 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while attempting quadratic backtracking! %D \n",snes->nfuncs);CHKERRQ(ierr); 2015 *flag = PETSC_FALSE; 2016 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 2017 goto theend1; 2018 } 2019 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 2020 if (snes->ops->solve != SNESSolveVI_SS) { 2021 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 2022 } else { 2023 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 2024 } 2025 if (snes->domainerror) { 2026 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 2027 PetscFunctionReturn(0); 2028 } 2029 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 2030 if (vi->lsmonitor) { 2031 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2032 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line search: gnorm after quadratic fit %G\n",*gnorm);CHKERRQ(ierr); 2033 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2034 } 2035 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* sufficient reduction */ 2036 if (vi->lsmonitor) { 2037 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2038 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line search: Quadratically determined step, lambda=%18.16e\n",lambda);CHKERRQ(ierr); 2039 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2040 } 2041 goto theend1; 2042 } 2043 2044 /* Fit points with cubic */ 2045 count = 1; 2046 while (PETSC_TRUE) { 2047 if (lambda <= minlambda) { 2048 if (vi->lsmonitor) { 2049 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2050 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line search: unable to find good step length! After %D tries \n",count);CHKERRQ(ierr); 2051 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line search: fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, minlambda=%18.16e, lambda=%18.16e, initial slope=%18.16e\n",fnorm,*gnorm,*ynorm,minlambda,lambda,initslope);CHKERRQ(ierr); 2052 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2053 } 2054 *flag = PETSC_FALSE; 2055 break; 2056 } 2057 t1 = .5*((*gnorm)*(*gnorm) - fnorm*fnorm) - lambda*initslope; 2058 t2 = .5*(gnormprev*gnormprev - fnorm*fnorm) - lambdaprev*initslope; 2059 a = (t1/(lambda*lambda) - t2/(lambdaprev*lambdaprev))/(lambda-lambdaprev); 2060 b = (-lambdaprev*t1/(lambda*lambda) + lambda*t2/(lambdaprev*lambdaprev))/(lambda-lambdaprev); 2061 d = b*b - 3*a*initslope; 2062 if (d < 0.0) d = 0.0; 2063 if (a == 0.0) { 2064 lambdatemp = -initslope/(2.0*b); 2065 } else { 2066 lambdatemp = (-b + sqrt(d))/(3.0*a); 2067 } 2068 lambdaprev = lambda; 2069 gnormprev = *gnorm; 2070 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 2071 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 2072 else lambda = lambdatemp; 2073 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 2074 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 2075 if (snes->nfuncs >= snes->max_funcs) { 2076 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while looking for good step length! %D \n",count);CHKERRQ(ierr); 2077 ierr = PetscInfo5(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lambda=%18.16e, initial slope=%18.16e\n",fnorm,*gnorm,*ynorm,lambda,initslope);CHKERRQ(ierr); 2078 *flag = PETSC_FALSE; 2079 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 2080 break; 2081 } 2082 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 2083 if (snes->ops->solve != SNESSolveVI_SS) { 2084 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 2085 } else { 2086 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 2087 } 2088 if (snes->domainerror) { 2089 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 2090 PetscFunctionReturn(0); 2091 } 2092 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 2093 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* is reduction enough? */ 2094 if (vi->lsmonitor) { 2095 ierr = PetscPrintf(comm," Line search: Cubically determined step, current gnorm %G lambda=%18.16e\n",*gnorm,lambda);CHKERRQ(ierr); 2096 } 2097 break; 2098 } else { 2099 if (vi->lsmonitor) { 2100 ierr = PetscPrintf(comm," Line search: Cubic step no good, shrinking lambda, current gnorm %G lambda=%18.16e\n",*gnorm,lambda);CHKERRQ(ierr); 2101 } 2102 } 2103 count++; 2104 } 2105 theend1: 2106 /* Optional user-defined check for line search step validity */ 2107 if (vi->postcheckstep && *flag) { 2108 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 2109 if (changed_y) { 2110 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 2111 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 2112 } 2113 if (changed_y || changed_w) { /* recompute the function if the step has changed */ 2114 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 2115 if (snes->ops->solve != SNESSolveVI_SS) { 2116 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 2117 } else { 2118 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 2119 } 2120 if (snes->domainerror) { 2121 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 2122 PetscFunctionReturn(0); 2123 } 2124 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 2125 ierr = VecNormBegin(y,NORM_2,ynorm);CHKERRQ(ierr); 2126 ierr = VecNormEnd(y,NORM_2,ynorm);CHKERRQ(ierr); 2127 } 2128 } 2129 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 2130 PetscFunctionReturn(0); 2131 } 2132 2133 #undef __FUNCT__ 2134 #define __FUNCT__ "SNESLineSearchQuadratic_VI" 2135 /* 2136 This routine does a quadratic line search while keeping the iterates within the variable bounds 2137 */ 2138 PetscErrorCode SNESLineSearchQuadratic_VI(SNES snes,void *lsctx,Vec x,Vec f,Vec g,Vec y,Vec w,PetscReal fnorm,PetscReal xnorm,PetscReal *ynorm,PetscReal *gnorm,PetscBool *flag) 2139 { 2140 /* 2141 Note that for line search purposes we work with with the related 2142 minimization problem: 2143 min z(x): R^n -> R, 2144 where z(x) = .5 * fnorm*fnorm,and fnorm = || f ||_2. 2145 */ 2146 PetscReal initslope,minlambda,lambda,lambdatemp,rellength; 2147 #if defined(PETSC_USE_COMPLEX) 2148 PetscScalar cinitslope; 2149 #endif 2150 PetscErrorCode ierr; 2151 PetscInt count; 2152 SNES_VI *vi = (SNES_VI*)snes->data; 2153 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 2154 2155 PetscFunctionBegin; 2156 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 2157 *flag = PETSC_TRUE; 2158 2159 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); 2160 if (*ynorm == 0.0) { 2161 if (vi->lsmonitor) { 2162 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2163 ierr = PetscViewerASCIIPrintf(vi->lsmonitor,"Line search: Direction and size is 0\n");CHKERRQ(ierr); 2164 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2165 } 2166 *gnorm = fnorm; 2167 ierr = VecCopy(x,w);CHKERRQ(ierr); 2168 ierr = VecCopy(f,g);CHKERRQ(ierr); 2169 *flag = PETSC_FALSE; 2170 goto theend2; 2171 } 2172 if (*ynorm > vi->maxstep) { /* Step too big, so scale back */ 2173 ierr = VecScale(y,vi->maxstep/(*ynorm));CHKERRQ(ierr); 2174 *ynorm = vi->maxstep; 2175 } 2176 ierr = VecMaxPointwiseDivide(y,x,&rellength);CHKERRQ(ierr); 2177 minlambda = vi->minlambda/rellength; 2178 ierr = MatMult(snes->jacobian,y,w);CHKERRQ(ierr); 2179 #if defined(PETSC_USE_COMPLEX) 2180 ierr = VecDot(f,w,&cinitslope);CHKERRQ(ierr); 2181 initslope = PetscRealPart(cinitslope); 2182 #else 2183 ierr = VecDot(f,w,&initslope);CHKERRQ(ierr); 2184 #endif 2185 if (initslope > 0.0) initslope = -initslope; 2186 if (initslope == 0.0) initslope = -1.0; 2187 ierr = PetscInfo1(snes,"Initslope %G \n",initslope);CHKERRQ(ierr); 2188 2189 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 2190 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 2191 if (snes->nfuncs >= snes->max_funcs) { 2192 ierr = PetscInfo(snes,"Exceeded maximum function evaluations, while checking full step length!\n");CHKERRQ(ierr); 2193 *flag = PETSC_FALSE; 2194 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 2195 goto theend2; 2196 } 2197 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 2198 if (snes->ops->solve != SNESSolveVI_SS) { 2199 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 2200 } else { 2201 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 2202 } 2203 if (snes->domainerror) { 2204 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 2205 PetscFunctionReturn(0); 2206 } 2207 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 2208 if (.5*(*gnorm)*(*gnorm) <= .5*fnorm*fnorm + vi->alpha*initslope) { /* Sufficient reduction */ 2209 if (vi->lsmonitor) { 2210 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2211 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 2212 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2213 } 2214 goto theend2; 2215 } 2216 2217 /* Fit points with quadratic */ 2218 lambda = 1.0; 2219 count = 1; 2220 while (PETSC_TRUE) { 2221 if (lambda <= minlambda) { /* bad luck; use full step */ 2222 if (vi->lsmonitor) { 2223 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2224 ierr = PetscViewerASCIIPrintf(vi->lsmonitor,"Line search: Unable to find good step length! %D \n",count);CHKERRQ(ierr); 2225 ierr = PetscViewerASCIIPrintf(vi->lsmonitor,"Line search: fnorm=%G, gnorm=%G, ynorm=%G, lambda=%G, initial slope=%G\n",fnorm,*gnorm,*ynorm,lambda,initslope);CHKERRQ(ierr); 2226 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2227 } 2228 ierr = VecCopy(x,w);CHKERRQ(ierr); 2229 *flag = PETSC_FALSE; 2230 break; 2231 } 2232 lambdatemp = -initslope/((*gnorm)*(*gnorm) - fnorm*fnorm - 2.0*initslope); 2233 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 2234 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 2235 else lambda = lambdatemp; 2236 2237 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 2238 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 2239 if (snes->nfuncs >= snes->max_funcs) { 2240 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while looking for good step length! %D \n",count);CHKERRQ(ierr); 2241 ierr = PetscInfo5(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lambda=%18.16e, initial slope=%18.16e\n",fnorm,*gnorm,*ynorm,lambda,initslope);CHKERRQ(ierr); 2242 *flag = PETSC_FALSE; 2243 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 2244 break; 2245 } 2246 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 2247 if (snes->domainerror) { 2248 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 2249 PetscFunctionReturn(0); 2250 } 2251 if (snes->ops->solve != SNESSolveVI_SS) { 2252 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 2253 } else { 2254 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 2255 } 2256 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 2257 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* sufficient reduction */ 2258 if (vi->lsmonitor) { 2259 ierr = PetscViewerASCIIAddTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2260 ierr = PetscViewerASCIIPrintf(vi->lsmonitor," Line Search: Quadratically determined step, lambda=%G\n",lambda);CHKERRQ(ierr); 2261 ierr = PetscViewerASCIISubtractTab(vi->lsmonitor,((PetscObject)snes)->tablevel);CHKERRQ(ierr); 2262 } 2263 break; 2264 } 2265 count++; 2266 } 2267 theend2: 2268 /* Optional user-defined check for line search step validity */ 2269 if (vi->postcheckstep) { 2270 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 2271 if (changed_y) { 2272 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 2273 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 2274 } 2275 if (changed_y || changed_w) { /* recompute the function if the step has changed */ 2276 ierr = SNESComputeFunction(snes,w,g); 2277 if (snes->domainerror) { 2278 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 2279 PetscFunctionReturn(0); 2280 } 2281 if (snes->ops->solve != SNESSolveVI_SS) { 2282 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 2283 } else { 2284 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 2285 } 2286 2287 ierr = VecNormBegin(y,NORM_2,ynorm);CHKERRQ(ierr); 2288 ierr = VecNormEnd(y,NORM_2,ynorm);CHKERRQ(ierr); 2289 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 2290 } 2291 } 2292 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 2293 PetscFunctionReturn(0); 2294 } 2295 2296 typedef PetscErrorCode (*FCN2)(SNES,void*,Vec,Vec,Vec,Vec,Vec,PetscReal,PetscReal,PetscReal*,PetscReal*,PetscBool*); /* force argument to next function to not be extern C*/ 2297 /* -------------------------------------------------------------------------- */ 2298 EXTERN_C_BEGIN 2299 #undef __FUNCT__ 2300 #define __FUNCT__ "SNESLineSearchSet_VI" 2301 PetscErrorCode SNESLineSearchSet_VI(SNES snes,FCN2 func,void *lsctx) 2302 { 2303 PetscFunctionBegin; 2304 ((SNES_VI *)(snes->data))->LineSearch = func; 2305 ((SNES_VI *)(snes->data))->lsP = lsctx; 2306 PetscFunctionReturn(0); 2307 } 2308 EXTERN_C_END 2309 2310 /* -------------------------------------------------------------------------- */ 2311 EXTERN_C_BEGIN 2312 #undef __FUNCT__ 2313 #define __FUNCT__ "SNESLineSearchSetMonitor_VI" 2314 PetscErrorCode SNESLineSearchSetMonitor_VI(SNES snes,PetscBool flg) 2315 { 2316 SNES_VI *vi = (SNES_VI*)snes->data; 2317 PetscErrorCode ierr; 2318 2319 PetscFunctionBegin; 2320 if (flg && !vi->lsmonitor) { 2321 ierr = PetscViewerASCIIOpen(((PetscObject)snes)->comm,"stdout",&vi->lsmonitor);CHKERRQ(ierr); 2322 } else if (!flg && vi->lsmonitor) { 2323 ierr = PetscViewerDestroy(&vi->lsmonitor);CHKERRQ(ierr); 2324 } 2325 PetscFunctionReturn(0); 2326 } 2327 EXTERN_C_END 2328 2329 /* 2330 SNESView_VI - Prints info from the SNESVI data structure. 2331 2332 Input Parameters: 2333 . SNES - the SNES context 2334 . viewer - visualization context 2335 2336 Application Interface Routine: SNESView() 2337 */ 2338 #undef __FUNCT__ 2339 #define __FUNCT__ "SNESView_VI" 2340 static PetscErrorCode SNESView_VI(SNES snes,PetscViewer viewer) 2341 { 2342 SNES_VI *vi = (SNES_VI *)snes->data; 2343 const char *cstr,*tstr; 2344 PetscErrorCode ierr; 2345 PetscBool iascii; 2346 2347 PetscFunctionBegin; 2348 ierr = PetscTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr); 2349 if (iascii) { 2350 if (vi->LineSearch == SNESLineSearchNo_VI) cstr = "SNESLineSearchNo"; 2351 else if (vi->LineSearch == SNESLineSearchQuadratic_VI) cstr = "SNESLineSearchQuadratic"; 2352 else if (vi->LineSearch == SNESLineSearchCubic_VI) cstr = "SNESLineSearchCubic"; 2353 else cstr = "unknown"; 2354 if (snes->ops->solve == SNESSolveVI_SS) tstr = "Semismooth"; 2355 else if (snes->ops->solve == SNESSolveVI_RS) tstr = "Reduced Space"; 2356 else if (snes->ops->solve == SNESSolveVI_RSAUG) tstr = "Reduced space with augmented variables"; 2357 else tstr = "unknown"; 2358 ierr = PetscViewerASCIIPrintf(viewer," VI algorithm: %s\n",tstr);CHKERRQ(ierr); 2359 ierr = PetscViewerASCIIPrintf(viewer," line search variant: %s\n",cstr);CHKERRQ(ierr); 2360 ierr = PetscViewerASCIIPrintf(viewer," alpha=%G, maxstep=%G, minlambda=%G\n",vi->alpha,vi->maxstep,vi->minlambda);CHKERRQ(ierr); 2361 } else { 2362 SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Viewer type %s not supported for SNES EQ VI",((PetscObject)viewer)->type_name); 2363 } 2364 PetscFunctionReturn(0); 2365 } 2366 2367 #undef __FUNCT__ 2368 #define __FUNCT__ "SNESVISetVariableBounds" 2369 /*@ 2370 SNESVISetVariableBounds - Sets the lower and upper bounds for the solution vector. xl <= x <= xu. 2371 2372 Input Parameters: 2373 . snes - the SNES context. 2374 . xl - lower bound. 2375 . xu - upper bound. 2376 2377 Notes: 2378 If this routine is not called then the lower and upper bounds are set to 2379 SNES_VI_INF and SNES_VI_NINF respectively during SNESSetUp(). 2380 2381 @*/ 2382 PetscErrorCode SNESVISetVariableBounds(SNES snes, Vec xl, Vec xu) 2383 { 2384 SNES_VI *vi; 2385 PetscErrorCode ierr; 2386 2387 PetscFunctionBegin; 2388 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 2389 PetscValidHeaderSpecific(xl,VEC_CLASSID,2); 2390 PetscValidHeaderSpecific(xu,VEC_CLASSID,3); 2391 if (!snes->vec_func) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call SNESSetFunction() first"); 2392 if (xl->map->N != snes->vec_func->map->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Incompatible vector lengths lower bound = %D solution vector = %D",xl->map->N,snes->vec_func->map->N); 2393 if (xu->map->N != snes->vec_func->map->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Incompatible vector lengths: upper bound = %D solution vector = %D",xu->map->N,snes->vec_func->map->N); 2394 ierr = SNESSetType(snes,SNESVI);CHKERRQ(ierr); 2395 vi = (SNES_VI*)snes->data; 2396 ierr = PetscObjectReference((PetscObject)xl);CHKERRQ(ierr); 2397 ierr = PetscObjectReference((PetscObject)xu);CHKERRQ(ierr); 2398 ierr = VecDestroy(&vi->xl);CHKERRQ(ierr); 2399 ierr = VecDestroy(&vi->xu);CHKERRQ(ierr); 2400 vi->xl = xl; 2401 vi->xu = xu; 2402 PetscFunctionReturn(0); 2403 } 2404 2405 /* -------------------------------------------------------------------------- */ 2406 /* 2407 SNESSetFromOptions_VI - Sets various parameters for the SNESVI method. 2408 2409 Input Parameter: 2410 . snes - the SNES context 2411 2412 Application Interface Routine: SNESSetFromOptions() 2413 */ 2414 #undef __FUNCT__ 2415 #define __FUNCT__ "SNESSetFromOptions_VI" 2416 static PetscErrorCode SNESSetFromOptions_VI(SNES snes) 2417 { 2418 SNES_VI *vi = (SNES_VI *)snes->data; 2419 const char *lses[] = {"basic","basicnonorms","quadratic","cubic"}; 2420 const char *vies[] = {"ss","rs","rsaug"}; 2421 PetscErrorCode ierr; 2422 PetscInt indx; 2423 PetscBool flg,set,flg2; 2424 2425 PetscFunctionBegin; 2426 ierr = PetscOptionsHead("SNES semismooth method options");CHKERRQ(ierr); 2427 ierr = PetscOptionsBool("-snes_vi_monitor","Monitor all non-active variables","None",PETSC_FALSE,&flg,0);CHKERRQ(ierr); 2428 if (flg) { 2429 ierr = SNESMonitorSet(snes,SNESMonitorVI,0,0);CHKERRQ(ierr); 2430 } 2431 ierr = PetscOptionsReal("-snes_ls_alpha","Function norm must decrease by","None",vi->alpha,&vi->alpha,0);CHKERRQ(ierr); 2432 ierr = PetscOptionsReal("-snes_ls_maxstep","Step must be less than","None",vi->maxstep,&vi->maxstep,0);CHKERRQ(ierr); 2433 ierr = PetscOptionsReal("-snes_ls_minlambda","Minimum lambda allowed","None",vi->minlambda,&vi->minlambda,0);CHKERRQ(ierr); 2434 ierr = PetscOptionsReal("-snes_vi_const_tol","constraint tolerance","None",vi->const_tol,&vi->const_tol,0);CHKERRQ(ierr); 2435 ierr = PetscOptionsBool("-snes_ls_monitor","Print progress of line searches","SNESLineSearchSetMonitor",vi->lsmonitor ? PETSC_TRUE : PETSC_FALSE,&flg,&set);CHKERRQ(ierr); 2436 if (set) {ierr = SNESLineSearchSetMonitor(snes,flg);CHKERRQ(ierr);} 2437 ierr = PetscOptionsEList("-snes_vi_type","Semismooth algorithm used","",vies,3,"ss",&indx,&flg2);CHKERRQ(ierr); 2438 if (flg2) { 2439 switch (indx) { 2440 case 0: 2441 snes->ops->solve = SNESSolveVI_SS; 2442 break; 2443 case 1: 2444 snes->ops->solve = SNESSolveVI_RS; 2445 break; 2446 case 2: 2447 snes->ops->solve = SNESSolveVI_RSAUG; 2448 } 2449 } 2450 ierr = PetscOptionsEList("-snes_ls","Line search used","SNESLineSearchSet",lses,4,"basic",&indx,&flg);CHKERRQ(ierr); 2451 if (flg) { 2452 switch (indx) { 2453 case 0: 2454 ierr = SNESLineSearchSet(snes,SNESLineSearchNo_VI,PETSC_NULL);CHKERRQ(ierr); 2455 break; 2456 case 1: 2457 ierr = SNESLineSearchSet(snes,SNESLineSearchNoNorms_VI,PETSC_NULL);CHKERRQ(ierr); 2458 break; 2459 case 2: 2460 ierr = SNESLineSearchSet(snes,SNESLineSearchQuadratic_VI,PETSC_NULL);CHKERRQ(ierr); 2461 break; 2462 case 3: 2463 ierr = SNESLineSearchSet(snes,SNESLineSearchCubic_VI,PETSC_NULL);CHKERRQ(ierr); 2464 break; 2465 } 2466 } 2467 ierr = PetscOptionsTail();CHKERRQ(ierr); 2468 PetscFunctionReturn(0); 2469 } 2470 /* -------------------------------------------------------------------------- */ 2471 /*MC 2472 SNESVI - Various solvers for variational inequalities based on Newton's method 2473 2474 Options Database: 2475 + -snes_vi_type <ss,rs,rsaug> a semi-smooth solver, a reduced space active set method and a reduced space active set method that does not eliminate the active constraints from the Jacobian instead augments the Jacobian with 2476 additional variables that enforce the constraints 2477 - -snes_vi_monitor - prints the number of active constraints at each iteration. 2478 2479 2480 Level: beginner 2481 2482 .seealso: SNESCreate(), SNES, SNESSetType(), SNESTR, SNESLineSearchSet(), 2483 SNESLineSearchSetPostCheck(), SNESLineSearchNo(), SNESLineSearchCubic(), SNESLineSearchQuadratic(), 2484 SNESLineSearchSet(), SNESLineSearchNoNorms(), SNESLineSearchSetPreCheck(), SNESLineSearchSetParams(), SNESLineSearchGetParams() 2485 2486 M*/ 2487 EXTERN_C_BEGIN 2488 #undef __FUNCT__ 2489 #define __FUNCT__ "SNESCreate_VI" 2490 PetscErrorCode SNESCreate_VI(SNES snes) 2491 { 2492 PetscErrorCode ierr; 2493 SNES_VI *vi; 2494 2495 PetscFunctionBegin; 2496 snes->ops->reset = SNESReset_VI; 2497 snes->ops->setup = SNESSetUp_VI; 2498 snes->ops->solve = SNESSolveVI_RS; 2499 snes->ops->destroy = SNESDestroy_VI; 2500 snes->ops->setfromoptions = SNESSetFromOptions_VI; 2501 snes->ops->view = SNESView_VI; 2502 snes->ops->converged = SNESDefaultConverged_VI; 2503 2504 ierr = PetscNewLog(snes,SNES_VI,&vi);CHKERRQ(ierr); 2505 snes->data = (void*)vi; 2506 vi->alpha = 1.e-4; 2507 vi->maxstep = 1.e8; 2508 vi->minlambda = 1.e-12; 2509 vi->LineSearch = SNESLineSearchNo_VI; 2510 vi->lsP = PETSC_NULL; 2511 vi->postcheckstep = PETSC_NULL; 2512 vi->postcheck = PETSC_NULL; 2513 vi->precheckstep = PETSC_NULL; 2514 vi->precheck = PETSC_NULL; 2515 vi->const_tol = 2.2204460492503131e-16; 2516 vi->checkredundancy = PETSC_NULL; 2517 2518 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSetMonitor_C","SNESLineSearchSetMonitor_VI",SNESLineSearchSetMonitor_VI);CHKERRQ(ierr); 2519 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSet_C","SNESLineSearchSet_VI",SNESLineSearchSet_VI);CHKERRQ(ierr); 2520 2521 PetscFunctionReturn(0); 2522 } 2523 EXTERN_C_END 2524