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 6 #undef __FUNCT__ 7 #define __FUNCT__ "SNESMonitorVI" 8 PetscErrorCode SNESMonitorVI(SNES snes,PetscInt its,PetscReal fgnorm,void *dummy) 9 { 10 PetscErrorCode ierr; 11 SNES_VI *vi = (SNES_VI*)snes->data; 12 PetscViewerASCIIMonitor viewer = (PetscViewerASCIIMonitor) dummy; 13 const PetscScalar *x,*xl,*xu,*f; 14 PetscInt i,n,act = 0; 15 PetscReal rnorm,fnorm; 16 17 PetscFunctionBegin; 18 if (!dummy) { 19 ierr = PetscViewerASCIIMonitorCreate(((PetscObject)snes)->comm,"stdout",0,&viewer);CHKERRQ(ierr); 20 } 21 ierr = VecGetLocalSize(snes->vec_sol,&n);CHKERRQ(ierr); 22 ierr = VecGetArrayRead(vi->xl,&xl);CHKERRQ(ierr); 23 ierr = VecGetArrayRead(vi->xu,&xu);CHKERRQ(ierr); 24 ierr = VecGetArrayRead(snes->vec_sol,&x);CHKERRQ(ierr); 25 ierr = VecGetArrayRead(snes->vec_func,&f);CHKERRQ(ierr); 26 27 rnorm = 0.0; 28 for (i=0; i<n; i++) { 29 if (((x[i] > xl[i] + 1.e-8 || (f[i] < 0.0)) && ((x[i] < xu[i] - 1.e-8) || f[i] > 0.0))) rnorm += f[i]*f[i]; 30 else act++; 31 } 32 ierr = VecRestoreArrayRead(snes->vec_func,&f);CHKERRQ(ierr); 33 ierr = VecRestoreArrayRead(vi->xl,&xl);CHKERRQ(ierr); 34 ierr = VecRestoreArrayRead(vi->xu,&xu);CHKERRQ(ierr); 35 ierr = VecRestoreArrayRead(snes->vec_sol,&x);CHKERRQ(ierr); 36 ierr = MPI_Allreduce(&rnorm,&fnorm,1,MPIU_REAL,MPIU_SUM,((PetscObject)snes)->comm);CHKERRQ(ierr); 37 fnorm = sqrt(fnorm); 38 ierr = PetscViewerASCIIMonitorPrintf(viewer,"%3D SNES VI Function norm %14.12e Active constraints %D\n",its,fnorm,act);CHKERRQ(ierr); 39 if (!dummy) { 40 ierr = PetscViewerASCIIMonitorDestroy(&viewer);CHKERRQ(ierr); 41 } 42 PetscFunctionReturn(0); 43 } 44 45 /* 46 Checks if J^T F = 0 which implies we've found a local minimum of the norm of the function, 47 || 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 48 0 = (J^T F)^T W = F^T J W iff W not in the null space of J. Thanks for Jorge More 49 for this trick. One assumes that the probability that W is in the null space of J is very, very small. 50 */ 51 #undef __FUNCT__ 52 #define __FUNCT__ "SNESVICheckLocalMin_Private" 53 PetscErrorCode SNESVICheckLocalMin_Private(SNES snes,Mat A,Vec F,Vec W,PetscReal fnorm,PetscBool *ismin) 54 { 55 PetscReal a1; 56 PetscErrorCode ierr; 57 PetscBool hastranspose; 58 59 PetscFunctionBegin; 60 *ismin = PETSC_FALSE; 61 ierr = MatHasOperation(A,MATOP_MULT_TRANSPOSE,&hastranspose);CHKERRQ(ierr); 62 if (hastranspose) { 63 /* Compute || J^T F|| */ 64 ierr = MatMultTranspose(A,F,W);CHKERRQ(ierr); 65 ierr = VecNorm(W,NORM_2,&a1);CHKERRQ(ierr); 66 ierr = PetscInfo1(snes,"|| J^T F|| %G near zero implies found a local minimum\n",a1/fnorm);CHKERRQ(ierr); 67 if (a1/fnorm < 1.e-4) *ismin = PETSC_TRUE; 68 } else { 69 Vec work; 70 PetscScalar result; 71 PetscReal wnorm; 72 73 ierr = VecSetRandom(W,PETSC_NULL);CHKERRQ(ierr); 74 ierr = VecNorm(W,NORM_2,&wnorm);CHKERRQ(ierr); 75 ierr = VecDuplicate(W,&work);CHKERRQ(ierr); 76 ierr = MatMult(A,W,work);CHKERRQ(ierr); 77 ierr = VecDot(F,work,&result);CHKERRQ(ierr); 78 ierr = VecDestroy(&work);CHKERRQ(ierr); 79 a1 = PetscAbsScalar(result)/(fnorm*wnorm); 80 ierr = PetscInfo1(snes,"(F^T J random)/(|| F ||*||random|| %G near zero implies found a local minimum\n",a1);CHKERRQ(ierr); 81 if (a1 < 1.e-4) *ismin = PETSC_TRUE; 82 } 83 PetscFunctionReturn(0); 84 } 85 86 /* 87 Checks if J^T(F - J*X) = 0 88 */ 89 #undef __FUNCT__ 90 #define __FUNCT__ "SNESVICheckResidual_Private" 91 PetscErrorCode SNESVICheckResidual_Private(SNES snes,Mat A,Vec F,Vec X,Vec W1,Vec W2) 92 { 93 PetscReal a1,a2; 94 PetscErrorCode ierr; 95 PetscBool hastranspose; 96 97 PetscFunctionBegin; 98 ierr = MatHasOperation(A,MATOP_MULT_TRANSPOSE,&hastranspose);CHKERRQ(ierr); 99 if (hastranspose) { 100 ierr = MatMult(A,X,W1);CHKERRQ(ierr); 101 ierr = VecAXPY(W1,-1.0,F);CHKERRQ(ierr); 102 103 /* Compute || J^T W|| */ 104 ierr = MatMultTranspose(A,W1,W2);CHKERRQ(ierr); 105 ierr = VecNorm(W1,NORM_2,&a1);CHKERRQ(ierr); 106 ierr = VecNorm(W2,NORM_2,&a2);CHKERRQ(ierr); 107 if (a1 != 0.0) { 108 ierr = PetscInfo1(snes,"||J^T(F-Ax)||/||F-AX|| %G near zero implies inconsistent rhs\n",a2/a1);CHKERRQ(ierr); 109 } 110 } 111 PetscFunctionReturn(0); 112 } 113 114 /* 115 SNESDefaultConverged_VI - Checks the convergence of the semismooth newton algorithm. 116 117 Notes: 118 The convergence criterion currently implemented is 119 merit < abstol 120 merit < rtol*merit_initial 121 */ 122 #undef __FUNCT__ 123 #define __FUNCT__ "SNESDefaultConverged_VI" 124 PetscErrorCode SNESDefaultConverged_VI(SNES snes,PetscInt it,PetscReal xnorm,PetscReal gradnorm,PetscReal fnorm,SNESConvergedReason *reason,void *dummy) 125 { 126 PetscErrorCode ierr; 127 128 PetscFunctionBegin; 129 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 130 PetscValidPointer(reason,6); 131 132 *reason = SNES_CONVERGED_ITERATING; 133 134 if (!it) { 135 /* set parameter for default relative tolerance convergence test */ 136 snes->ttol = fnorm*snes->rtol; 137 } 138 if (fnorm != fnorm) { 139 ierr = PetscInfo(snes,"Failed to converged, function norm is NaN\n");CHKERRQ(ierr); 140 *reason = SNES_DIVERGED_FNORM_NAN; 141 } else if (fnorm < snes->abstol) { 142 ierr = PetscInfo2(snes,"Converged due to function norm %G < %G\n",fnorm,snes->abstol);CHKERRQ(ierr); 143 *reason = SNES_CONVERGED_FNORM_ABS; 144 } else if (snes->nfuncs >= snes->max_funcs) { 145 ierr = PetscInfo2(snes,"Exceeded maximum number of function evaluations: %D > %D\n",snes->nfuncs,snes->max_funcs);CHKERRQ(ierr); 146 *reason = SNES_DIVERGED_FUNCTION_COUNT; 147 } 148 149 if (it && !*reason) { 150 if (fnorm < snes->ttol) { 151 ierr = PetscInfo2(snes,"Converged due to function norm %G < %G (relative tolerance)\n",fnorm,snes->ttol);CHKERRQ(ierr); 152 *reason = SNES_CONVERGED_FNORM_RELATIVE; 153 } 154 } 155 PetscFunctionReturn(0); 156 } 157 158 /* 159 SNESVIComputeMeritFunction - Evaluates the merit function for the mixed complementarity problem. 160 161 Input Parameter: 162 . phi - the semismooth function 163 164 Output Parameter: 165 . merit - the merit function 166 . phinorm - ||phi|| 167 168 Notes: 169 The merit function for the mixed complementarity problem is defined as 170 merit = 0.5*phi^T*phi 171 */ 172 #undef __FUNCT__ 173 #define __FUNCT__ "SNESVIComputeMeritFunction" 174 static PetscErrorCode SNESVIComputeMeritFunction(Vec phi, PetscReal* merit,PetscReal* phinorm) 175 { 176 PetscErrorCode ierr; 177 178 PetscFunctionBegin; 179 ierr = VecNormBegin(phi,NORM_2,phinorm);CHKERRQ(ierr); 180 ierr = VecNormEnd(phi,NORM_2,phinorm);CHKERRQ(ierr); 181 182 *merit = 0.5*(*phinorm)*(*phinorm); 183 PetscFunctionReturn(0); 184 } 185 186 PETSC_STATIC_INLINE PetscScalar Phi(PetscScalar a,PetscScalar b) 187 { 188 return a + b - sqrt(a*a + b*b); 189 } 190 191 PETSC_STATIC_INLINE PetscScalar DPhi(PetscScalar a,PetscScalar b) 192 { 193 if ((PetscAbsScalar(a) >= 1.e-6) || (PetscAbsScalar(b) >= 1.e-6)) return 1.0 - a/ sqrt(a*a + b*b); 194 else return .5; 195 } 196 197 /* 198 SNESVIComputeFunction - Reformulates a system of nonlinear equations in mixed complementarity form to a system of nonlinear equations in semismooth form. 199 200 Input Parameters: 201 . snes - the SNES context 202 . x - current iterate 203 . functx - user defined function context 204 205 Output Parameters: 206 . phi - Semismooth function 207 208 */ 209 #undef __FUNCT__ 210 #define __FUNCT__ "SNESVIComputeFunction" 211 static PetscErrorCode SNESVIComputeFunction(SNES snes,Vec X,Vec phi,void* functx) 212 { 213 PetscErrorCode ierr; 214 SNES_VI *vi = (SNES_VI*)snes->data; 215 Vec Xl = vi->xl,Xu = vi->xu,F = snes->vec_func; 216 PetscScalar *phi_arr,*x_arr,*f_arr,*l,*u; 217 PetscInt i,nlocal; 218 219 PetscFunctionBegin; 220 ierr = (*vi->computeuserfunction)(snes,X,F,functx);CHKERRQ(ierr); 221 ierr = VecGetLocalSize(X,&nlocal);CHKERRQ(ierr); 222 ierr = VecGetArray(X,&x_arr);CHKERRQ(ierr); 223 ierr = VecGetArray(F,&f_arr);CHKERRQ(ierr); 224 ierr = VecGetArray(Xl,&l);CHKERRQ(ierr); 225 ierr = VecGetArray(Xu,&u);CHKERRQ(ierr); 226 ierr = VecGetArray(phi,&phi_arr);CHKERRQ(ierr); 227 228 for (i=0;i < nlocal;i++) { 229 if ((l[i] <= PETSC_VI_NINF) && (u[i] >= PETSC_VI_INF)) { /* no constraints on variable */ 230 phi_arr[i] = f_arr[i]; 231 } else if (l[i] <= PETSC_VI_NINF) { /* upper bound on variable only */ 232 phi_arr[i] = -Phi(u[i] - x_arr[i],-f_arr[i]); 233 } else if (u[i] >= PETSC_VI_INF) { /* lower bound on variable only */ 234 phi_arr[i] = Phi(x_arr[i] - l[i],f_arr[i]); 235 } else if (l[i] == u[i]) { 236 phi_arr[i] = l[i] - x_arr[i]; 237 } else { /* both bounds on variable */ 238 phi_arr[i] = Phi(x_arr[i] - l[i],-Phi(u[i] - x_arr[i],-f_arr[i])); 239 } 240 } 241 242 ierr = VecRestoreArray(X,&x_arr);CHKERRQ(ierr); 243 ierr = VecRestoreArray(F,&f_arr);CHKERRQ(ierr); 244 ierr = VecRestoreArray(Xl,&l);CHKERRQ(ierr); 245 ierr = VecRestoreArray(Xu,&u);CHKERRQ(ierr); 246 ierr = VecRestoreArray(phi,&phi_arr);CHKERRQ(ierr); 247 PetscFunctionReturn(0); 248 } 249 250 /* 251 SNESVIComputeBsubdifferentialVectors - Computes the diagonal shift (Da) and row scaling (Db) vectors needed for the 252 the semismooth jacobian. 253 */ 254 #undef __FUNCT__ 255 #define __FUNCT__ "SNESVIComputeBsubdifferentialVectors" 256 PetscErrorCode SNESVIComputeBsubdifferentialVectors(SNES snes,Vec X,Vec F,Mat jac,Vec Da,Vec Db) 257 { 258 PetscErrorCode ierr; 259 SNES_VI *vi = (SNES_VI*)snes->data; 260 PetscScalar *l,*u,*x,*f,*da,*db,da1,da2,db1,db2; 261 PetscInt i,nlocal; 262 263 PetscFunctionBegin; 264 265 ierr = VecGetArray(X,&x);CHKERRQ(ierr); 266 ierr = VecGetArray(F,&f);CHKERRQ(ierr); 267 ierr = VecGetArray(vi->xl,&l);CHKERRQ(ierr); 268 ierr = VecGetArray(vi->xu,&u);CHKERRQ(ierr); 269 ierr = VecGetArray(Da,&da);CHKERRQ(ierr); 270 ierr = VecGetArray(Db,&db);CHKERRQ(ierr); 271 ierr = VecGetLocalSize(X,&nlocal);CHKERRQ(ierr); 272 273 for (i=0;i< nlocal;i++) { 274 if ((l[i] <= PETSC_VI_NINF) && (u[i] >= PETSC_VI_INF)) {/* no constraints on variable */ 275 da[i] = 0; 276 db[i] = 1; 277 } else if (l[i] <= PETSC_VI_NINF) { /* upper bound on variable only */ 278 da[i] = DPhi(u[i] - x[i], -f[i]); 279 db[i] = DPhi(-f[i],u[i] - x[i]); 280 } else if (u[i] >= PETSC_VI_INF) { /* lower bound on variable only */ 281 da[i] = DPhi(x[i] - l[i], f[i]); 282 db[i] = DPhi(f[i],x[i] - l[i]); 283 } else if (l[i] == u[i]) { /* fixed variable */ 284 da[i] = 1; 285 db[i] = 0; 286 } else { /* upper and lower bounds on variable */ 287 da1 = DPhi(x[i] - l[i], -Phi(u[i] - x[i], -f[i])); 288 db1 = DPhi(-Phi(u[i] - x[i], -f[i]),x[i] - l[i]); 289 da2 = DPhi(u[i] - x[i], -f[i]); 290 db2 = DPhi(-f[i],u[i] - x[i]); 291 da[i] = da1 + db1*da2; 292 db[i] = db1*db2; 293 } 294 } 295 296 ierr = VecRestoreArray(X,&x);CHKERRQ(ierr); 297 ierr = VecRestoreArray(F,&f);CHKERRQ(ierr); 298 ierr = VecRestoreArray(vi->xl,&l);CHKERRQ(ierr); 299 ierr = VecRestoreArray(vi->xu,&u);CHKERRQ(ierr); 300 ierr = VecRestoreArray(Da,&da);CHKERRQ(ierr); 301 ierr = VecRestoreArray(Db,&db);CHKERRQ(ierr); 302 PetscFunctionReturn(0); 303 } 304 305 /* 306 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. 307 308 Input Parameters: 309 . Da - Diagonal shift vector for the semismooth jacobian. 310 . Db - Row scaling vector for the semismooth jacobian. 311 312 Output Parameters: 313 . jac - semismooth jacobian 314 . jac_pre - optional preconditioning matrix 315 316 Notes: 317 The semismooth jacobian matrix is given by 318 jac = Da + Db*jacfun 319 where Db is the row scaling matrix stored as a vector, 320 Da is the diagonal perturbation matrix stored as a vector 321 and jacfun is the jacobian of the original nonlinear function. 322 */ 323 #undef __FUNCT__ 324 #define __FUNCT__ "SNESVIComputeJacobian" 325 PetscErrorCode SNESVIComputeJacobian(Mat jac, Mat jac_pre,Vec Da, Vec Db) 326 { 327 PetscErrorCode ierr; 328 329 /* Do row scaling and add diagonal perturbation */ 330 ierr = MatDiagonalScale(jac,Db,PETSC_NULL);CHKERRQ(ierr); 331 ierr = MatDiagonalSet(jac,Da,ADD_VALUES);CHKERRQ(ierr); 332 if (jac != jac_pre) { /* If jac and jac_pre are different */ 333 ierr = MatDiagonalScale(jac_pre,Db,PETSC_NULL); 334 ierr = MatDiagonalSet(jac_pre,Da,ADD_VALUES);CHKERRQ(ierr); 335 } 336 PetscFunctionReturn(0); 337 } 338 339 /* 340 SNESVIComputeMeritFunctionGradient - Computes the gradient of the merit function psi. 341 342 Input Parameters: 343 phi - semismooth function. 344 H - semismooth jacobian 345 346 Output Parameters: 347 dpsi - merit function gradient 348 349 Notes: 350 The merit function gradient is computed as follows 351 dpsi = H^T*phi 352 */ 353 #undef __FUNCT__ 354 #define __FUNCT__ "SNESVIComputeMeritFunctionGradient" 355 PetscErrorCode SNESVIComputeMeritFunctionGradient(Mat H, Vec phi, Vec dpsi) 356 { 357 PetscErrorCode ierr; 358 359 PetscFunctionBegin; 360 ierr = MatMultTranspose(H,phi,dpsi);CHKERRQ(ierr); 361 PetscFunctionReturn(0); 362 } 363 364 /* -------------------------------------------------------------------------- */ 365 /* 366 SNESVIProjectOntoBounds - Projects X onto the feasible region so that Xl[i] <= X[i] <= Xu[i] for i = 1...n. 367 368 Input Parameters: 369 . SNES - nonlinear solver context 370 371 Output Parameters: 372 . X - Bound projected X 373 374 */ 375 376 #undef __FUNCT__ 377 #define __FUNCT__ "SNESVIProjectOntoBounds" 378 PetscErrorCode SNESVIProjectOntoBounds(SNES snes,Vec X) 379 { 380 PetscErrorCode ierr; 381 SNES_VI *vi = (SNES_VI*)snes->data; 382 const PetscScalar *xl,*xu; 383 PetscScalar *x; 384 PetscInt i,n; 385 386 PetscFunctionBegin; 387 ierr = VecGetLocalSize(X,&n);CHKERRQ(ierr); 388 ierr = VecGetArray(X,&x);CHKERRQ(ierr); 389 ierr = VecGetArrayRead(vi->xl,&xl);CHKERRQ(ierr); 390 ierr = VecGetArrayRead(vi->xu,&xu);CHKERRQ(ierr); 391 392 for(i = 0;i<n;i++) { 393 if (x[i] < xl[i]) x[i] = xl[i]; 394 else if (x[i] > xu[i]) x[i] = xu[i]; 395 } 396 ierr = VecRestoreArray(X,&x);CHKERRQ(ierr); 397 ierr = VecRestoreArrayRead(vi->xl,&xl);CHKERRQ(ierr); 398 ierr = VecRestoreArrayRead(vi->xu,&xu);CHKERRQ(ierr); 399 PetscFunctionReturn(0); 400 } 401 402 /* -------------------------------------------------------------------- 403 404 This file implements a semismooth truncated Newton method with a line search, 405 for solving a system of nonlinear equations in complementarity form, using the KSP, Vec, 406 and Mat interfaces for linear solvers, vectors, and matrices, 407 respectively. 408 409 The following basic routines are required for each nonlinear solver: 410 SNESCreate_XXX() - Creates a nonlinear solver context 411 SNESSetFromOptions_XXX() - Sets runtime options 412 SNESSolve_XXX() - Solves the nonlinear system 413 SNESDestroy_XXX() - Destroys the nonlinear solver context 414 The suffix "_XXX" denotes a particular implementation, in this case 415 we use _VI (e.g., SNESCreate_VI, SNESSolve_VI) for solving 416 systems of nonlinear equations with a line search (LS) method. 417 These routines are actually called via the common user interface 418 routines SNESCreate(), SNESSetFromOptions(), SNESSolve(), and 419 SNESDestroy(), so the application code interface remains identical 420 for all nonlinear solvers. 421 422 Another key routine is: 423 SNESSetUp_XXX() - Prepares for the use of a nonlinear solver 424 by setting data structures and options. The interface routine SNESSetUp() 425 is not usually called directly by the user, but instead is called by 426 SNESSolve() if necessary. 427 428 Additional basic routines are: 429 SNESView_XXX() - Prints details of runtime options that 430 have actually been used. 431 These are called by application codes via the interface routines 432 SNESView(). 433 434 The various types of solvers (preconditioners, Krylov subspace methods, 435 nonlinear solvers, timesteppers) are all organized similarly, so the 436 above description applies to these categories also. 437 438 -------------------------------------------------------------------- */ 439 /* 440 SNESSolveVI_SS - Solves the complementarity problem with a semismooth Newton 441 method using a line search. 442 443 Input Parameters: 444 . snes - the SNES context 445 446 Output Parameter: 447 . outits - number of iterations until termination 448 449 Application Interface Routine: SNESSolve() 450 451 Notes: 452 This implements essentially a semismooth Newton method with a 453 line search. The default line search does not do any line seach 454 but rather takes a full newton step. 455 */ 456 #undef __FUNCT__ 457 #define __FUNCT__ "SNESSolveVI_SS" 458 PetscErrorCode SNESSolveVI_SS(SNES snes) 459 { 460 SNES_VI *vi = (SNES_VI*)snes->data; 461 PetscErrorCode ierr; 462 PetscInt maxits,i,lits; 463 PetscBool lssucceed; 464 MatStructure flg = DIFFERENT_NONZERO_PATTERN; 465 PetscReal gnorm,xnorm=0,ynorm; 466 Vec Y,X,F,G,W; 467 KSPConvergedReason kspreason; 468 469 PetscFunctionBegin; 470 vi->computeuserfunction = snes->ops->computefunction; 471 snes->ops->computefunction = SNESVIComputeFunction; 472 473 snes->numFailures = 0; 474 snes->numLinearSolveFailures = 0; 475 snes->reason = SNES_CONVERGED_ITERATING; 476 477 maxits = snes->max_its; /* maximum number of iterations */ 478 X = snes->vec_sol; /* solution vector */ 479 F = snes->vec_func; /* residual vector */ 480 Y = snes->work[0]; /* work vectors */ 481 G = snes->work[1]; 482 W = snes->work[2]; 483 484 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 485 snes->iter = 0; 486 snes->norm = 0.0; 487 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 488 489 ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr); 490 ierr = SNESComputeFunction(snes,X,vi->phi);CHKERRQ(ierr); 491 if (snes->domainerror) { 492 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 493 snes->ops->computefunction = vi->computeuserfunction; 494 PetscFunctionReturn(0); 495 } 496 /* Compute Merit function */ 497 ierr = SNESVIComputeMeritFunction(vi->phi,&vi->merit,&vi->phinorm);CHKERRQ(ierr); 498 499 ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr); /* xnorm <- ||x|| */ 500 ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr); 501 if (PetscIsInfOrNanReal(vi->merit)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 502 503 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 504 snes->norm = vi->phinorm; 505 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 506 SNESLogConvHistory(snes,vi->phinorm,0); 507 ierr = SNESMonitor(snes,0,vi->phinorm);CHKERRQ(ierr); 508 509 /* set parameter for default relative tolerance convergence test */ 510 snes->ttol = vi->phinorm*snes->rtol; 511 /* test convergence */ 512 ierr = (*snes->ops->converged)(snes,0,0.0,0.0,vi->phinorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 513 if (snes->reason) { 514 snes->ops->computefunction = vi->computeuserfunction; 515 PetscFunctionReturn(0); 516 } 517 518 for (i=0; i<maxits; i++) { 519 520 /* Call general purpose update function */ 521 if (snes->ops->update) { 522 ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr); 523 } 524 525 /* Solve J Y = Phi, where J is the semismooth jacobian */ 526 /* Get the nonlinear function jacobian */ 527 ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr); 528 /* Get the diagonal shift and row scaling vectors */ 529 ierr = SNESVIComputeBsubdifferentialVectors(snes,X,F,snes->jacobian,vi->Da,vi->Db);CHKERRQ(ierr); 530 /* Compute the semismooth jacobian */ 531 ierr = SNESVIComputeJacobian(snes->jacobian,snes->jacobian_pre,vi->Da,vi->Db);CHKERRQ(ierr); 532 /* Compute the merit function gradient */ 533 ierr = SNESVIComputeMeritFunctionGradient(snes->jacobian,vi->phi,vi->dpsi);CHKERRQ(ierr); 534 ierr = KSPSetOperators(snes->ksp,snes->jacobian,snes->jacobian_pre,flg);CHKERRQ(ierr); 535 ierr = SNES_KSPSolve(snes,snes->ksp,vi->phi,Y);CHKERRQ(ierr); 536 ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr); 537 538 if (kspreason < 0) { 539 if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) { 540 ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr); 541 snes->reason = SNES_DIVERGED_LINEAR_SOLVE; 542 break; 543 } 544 } 545 ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr); 546 snes->linear_its += lits; 547 ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr); 548 /* 549 if (vi->precheckstep) { 550 PetscBool changed_y = PETSC_FALSE; 551 ierr = (*vi->precheckstep)(snes,X,Y,vi->precheck,&changed_y);CHKERRQ(ierr); 552 } 553 554 if (PetscLogPrintInfo){ 555 ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr); 556 } 557 */ 558 /* Compute a (scaled) negative update in the line search routine: 559 Y <- X - lambda*Y 560 and evaluate G = function(Y) (depends on the line search). 561 */ 562 ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr); 563 ynorm = 1; gnorm = vi->phinorm; 564 ierr = (*vi->LineSearch)(snes,vi->lsP,X,vi->phi,G,Y,W,vi->phinorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr); 565 ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",vi->phinorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr); 566 if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break; 567 if (snes->domainerror) { 568 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 569 snes->ops->computefunction = vi->computeuserfunction; 570 PetscFunctionReturn(0); 571 } 572 if (!lssucceed) { 573 if (++snes->numFailures >= snes->maxFailures) { 574 PetscBool ismin; 575 snes->reason = SNES_DIVERGED_LINE_SEARCH; 576 ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr); 577 if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN; 578 break; 579 } 580 } 581 /* Update function and solution vectors */ 582 vi->phinorm = gnorm; 583 vi->merit = 0.5*vi->phinorm*vi->phinorm; 584 ierr = VecCopy(G,vi->phi);CHKERRQ(ierr); 585 ierr = VecCopy(W,X);CHKERRQ(ierr); 586 /* Monitor convergence */ 587 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 588 snes->iter = i+1; 589 snes->norm = vi->phinorm; 590 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 591 SNESLogConvHistory(snes,snes->norm,lits); 592 ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr); 593 /* Test for convergence, xnorm = || X || */ 594 if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); } 595 ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,vi->phinorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 596 if (snes->reason) break; 597 } 598 if (i == maxits) { 599 ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr); 600 if(!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT; 601 } 602 snes->ops->computefunction = vi->computeuserfunction; 603 PetscFunctionReturn(0); 604 } 605 606 #undef __FUNCT__ 607 #define __FUNCT__ "SNESVIGetActiveSetIS" 608 /* 609 SNESVIGetActiveSetIndices - Gets the global indices for the active set variables 610 611 Input parameter 612 . snes - the SNES context 613 . X - the snes solution vector 614 . F - the nonlinear function vector 615 616 Output parameter 617 . ISact - active set index set 618 */ 619 PetscErrorCode SNESVIGetActiveSetIS(SNES snes,Vec X,Vec F,IS* ISact) 620 { 621 PetscErrorCode ierr; 622 SNES_VI *vi = (SNES_VI*)snes->data; 623 Vec Xl=vi->xl,Xu=vi->xu; 624 const PetscScalar *x,*f,*xl,*xu; 625 PetscInt *idx_act,i,nlocal,nloc_isact=0,ilow,ihigh,i1=0; 626 627 PetscFunctionBegin; 628 ierr = VecGetLocalSize(X,&nlocal);CHKERRQ(ierr); 629 ierr = VecGetOwnershipRange(X,&ilow,&ihigh);CHKERRQ(ierr); 630 ierr = VecGetArrayRead(X,&x);CHKERRQ(ierr); 631 ierr = VecGetArrayRead(Xl,&xl);CHKERRQ(ierr); 632 ierr = VecGetArrayRead(Xu,&xu);CHKERRQ(ierr); 633 ierr = VecGetArrayRead(F,&f);CHKERRQ(ierr); 634 /* Compute active set size */ 635 for (i=0; i < nlocal;i++) { 636 if (!((x[i] > xl[i] + 1.e-8 || (f[i] < 0.0)) && ((x[i] < xu[i] - 1.e-8) || f[i] > 0.0))) nloc_isact++; 637 } 638 639 ierr = PetscMalloc(nloc_isact*sizeof(PetscInt),&idx_act);CHKERRQ(ierr); 640 641 /* Set active set indices */ 642 for(i=0; i < nlocal; i++) { 643 if (!((x[i] > xl[i] + 1.e-8 || (f[i] < 0.0)) && ((x[i] < xu[i] - 1.e-8) || f[i] > 0.0))) idx_act[i1++] = ilow+i; 644 } 645 646 /* Create active set IS */ 647 ierr = ISCreateGeneral(((PetscObject)snes)->comm,nloc_isact,idx_act,PETSC_OWN_POINTER,ISact);CHKERRQ(ierr); 648 649 ierr = VecRestoreArrayRead(X,&x);CHKERRQ(ierr); 650 ierr = VecRestoreArrayRead(Xl,&xl);CHKERRQ(ierr); 651 ierr = VecRestoreArrayRead(Xu,&xu);CHKERRQ(ierr); 652 ierr = VecRestoreArrayRead(F,&f);CHKERRQ(ierr); 653 PetscFunctionReturn(0); 654 } 655 656 #undef __FUNCT__ 657 #define __FUNCT__ "SNESVICreateIndexSets_RS" 658 PetscErrorCode SNESVICreateIndexSets_RS(SNES snes,Vec X,Vec F,IS* ISact,IS* ISinact) 659 { 660 PetscErrorCode ierr; 661 662 PetscFunctionBegin; 663 ierr = SNESVIGetActiveSetIS(snes,X,F,ISact);CHKERRQ(ierr); 664 ierr = ISComplement(*ISact,X->map->rstart,X->map->rend,ISinact);CHKERRQ(ierr); 665 PetscFunctionReturn(0); 666 } 667 668 /* Create active and inactive set vectors. The local size of this vector is set and petsc computes the global size */ 669 #undef __FUNCT__ 670 #define __FUNCT__ "SNESVICreateSubVectors" 671 PetscErrorCode SNESVICreateSubVectors(SNES snes,PetscInt n,Vec* newv) 672 { 673 PetscErrorCode ierr; 674 Vec v; 675 676 PetscFunctionBegin; 677 ierr = VecCreate(((PetscObject)snes)->comm,&v);CHKERRQ(ierr); 678 ierr = VecSetSizes(v,n,PETSC_DECIDE);CHKERRQ(ierr); 679 ierr = VecSetFromOptions(v);CHKERRQ(ierr); 680 *newv = v; 681 682 PetscFunctionReturn(0); 683 } 684 685 /* Resets the snes PC and KSP when the active set sizes change */ 686 #undef __FUNCT__ 687 #define __FUNCT__ "SNESVIResetPCandKSP" 688 PetscErrorCode SNESVIResetPCandKSP(SNES snes,Mat Amat,Mat Pmat) 689 { 690 PetscErrorCode ierr; 691 KSP kspnew,snesksp; 692 PC pcnew; 693 const MatSolverPackage stype; 694 695 PetscFunctionBegin; 696 /* The active and inactive set sizes have changed so need to create a new snes->ksp object */ 697 ierr = SNESGetKSP(snes,&snesksp);CHKERRQ(ierr); 698 ierr = KSPCreate(((PetscObject)snes)->comm,&kspnew);CHKERRQ(ierr); 699 /* Copy over snes->ksp info */ 700 kspnew->pc_side = snesksp->pc_side; 701 kspnew->rtol = snesksp->rtol; 702 kspnew->abstol = snesksp->abstol; 703 kspnew->max_it = snesksp->max_it; 704 ierr = KSPSetType(kspnew,((PetscObject)snesksp)->type_name);CHKERRQ(ierr); 705 ierr = KSPGetPC(kspnew,&pcnew);CHKERRQ(ierr); 706 ierr = PCSetType(kspnew->pc,((PetscObject)snesksp->pc)->type_name);CHKERRQ(ierr); 707 ierr = PCSetOperators(kspnew->pc,Amat,Pmat,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr); 708 ierr = PCFactorGetMatSolverPackage(snesksp->pc,&stype);CHKERRQ(ierr); 709 ierr = PCFactorSetMatSolverPackage(kspnew->pc,stype);CHKERRQ(ierr); 710 ierr = KSPDestroy(&snesksp);CHKERRQ(ierr); 711 snes->ksp = kspnew; 712 ierr = PetscLogObjectParent(snes,kspnew);CHKERRQ(ierr); 713 ierr = KSPSetFromOptions(kspnew);CHKERRQ(ierr); 714 PetscFunctionReturn(0); 715 } 716 717 718 #undef __FUNCT__ 719 #define __FUNCT__ "SNESVIComputeInactiveSetFnorm" 720 PetscErrorCode SNESVIComputeInactiveSetFnorm(SNES snes,Vec F,Vec X,PetscScalar *fnorm) 721 { 722 PetscErrorCode ierr; 723 SNES_VI *vi = (SNES_VI*)snes->data; 724 const PetscScalar *x,*xl,*xu,*f; 725 PetscInt i,n; 726 PetscReal rnorm; 727 728 PetscFunctionBegin; 729 ierr = VecGetLocalSize(X,&n);CHKERRQ(ierr); 730 ierr = VecGetArrayRead(vi->xl,&xl);CHKERRQ(ierr); 731 ierr = VecGetArrayRead(vi->xu,&xu);CHKERRQ(ierr); 732 ierr = VecGetArrayRead(X,&x);CHKERRQ(ierr); 733 ierr = VecGetArrayRead(F,&f);CHKERRQ(ierr); 734 rnorm = 0.0; 735 for (i=0; i<n; i++) { 736 if (((x[i] > xl[i] + 1.e-8 || (f[i] < 0.0)) && ((x[i] < xu[i] - 1.e-8) || f[i] > 0.0))) rnorm += f[i]*f[i]; 737 } 738 ierr = VecRestoreArrayRead(F,&f);CHKERRQ(ierr); 739 ierr = VecRestoreArrayRead(vi->xl,&xl);CHKERRQ(ierr); 740 ierr = VecRestoreArrayRead(vi->xu,&xu);CHKERRQ(ierr); 741 ierr = VecRestoreArrayRead(X,&x);CHKERRQ(ierr); 742 ierr = MPI_Allreduce(&rnorm,fnorm,1,MPIU_REAL,MPIU_SUM,((PetscObject)snes)->comm);CHKERRQ(ierr); 743 *fnorm = sqrt(*fnorm); 744 PetscFunctionReturn(0); 745 } 746 747 /* Variational Inequality solver using reduce space method. No semismooth algorithm is 748 implemented in this algorithm. It basically identifies the active variables and does 749 a linear solve on the inactive variables. */ 750 #undef __FUNCT__ 751 #define __FUNCT__ "SNESSolveVI_RS" 752 PetscErrorCode SNESSolveVI_RS(SNES snes) 753 { 754 SNES_VI *vi = (SNES_VI*)snes->data; 755 PetscErrorCode ierr; 756 PetscInt maxits,i,lits; 757 PetscBool lssucceed; 758 MatStructure flg = DIFFERENT_NONZERO_PATTERN; 759 PetscReal fnorm,gnorm,xnorm=0,ynorm; 760 Vec Y,X,F,G,W; 761 KSPConvergedReason kspreason; 762 763 PetscFunctionBegin; 764 snes->numFailures = 0; 765 snes->numLinearSolveFailures = 0; 766 snes->reason = SNES_CONVERGED_ITERATING; 767 768 maxits = snes->max_its; /* maximum number of iterations */ 769 X = snes->vec_sol; /* solution vector */ 770 F = snes->vec_func; /* residual vector */ 771 Y = snes->work[0]; /* work vectors */ 772 G = snes->work[1]; 773 W = snes->work[2]; 774 775 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 776 snes->iter = 0; 777 snes->norm = 0.0; 778 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 779 780 ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr); 781 ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr); 782 if (snes->domainerror) { 783 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 784 PetscFunctionReturn(0); 785 } 786 ierr = SNESVIComputeInactiveSetFnorm(snes,F,X,&fnorm);CHKERRQ(ierr); 787 ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr); /* xnorm <- ||x|| */ 788 ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr); 789 if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 790 791 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 792 snes->norm = fnorm; 793 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 794 SNESLogConvHistory(snes,fnorm,0); 795 ierr = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr); 796 797 /* set parameter for default relative tolerance convergence test */ 798 snes->ttol = fnorm*snes->rtol; 799 /* test convergence */ 800 ierr = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 801 if (snes->reason) PetscFunctionReturn(0); 802 803 for (i=0; i<maxits; i++) { 804 805 IS IS_act,IS_inact; /* _act -> active set _inact -> inactive set */ 806 VecScatter scat_act,scat_inact; 807 PetscInt nis_act,nis_inact; 808 Vec Y_act,Y_inact,F_inact; 809 Mat jac_inact_inact,prejac_inact_inact; 810 IS keptrows; 811 PetscBool isequal; 812 813 /* Call general purpose update function */ 814 if (snes->ops->update) { 815 ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr); 816 } 817 ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr); 818 819 /* Create active and inactive index sets */ 820 ierr = SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&IS_inact);CHKERRQ(ierr); 821 822 /* Create inactive set submatrix */ 823 ierr = MatGetSubMatrix(snes->jacobian,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);CHKERRQ(ierr); 824 ierr = MatFindNonzeroRows(jac_inact_inact,&keptrows);CHKERRQ(ierr); 825 if (keptrows) { 826 PetscInt cnt,*nrows,k; 827 const PetscInt *krows,*inact; 828 PetscInt rstart=jac_inact_inact->rmap->rstart; 829 830 ierr = MatDestroy(&jac_inact_inact);CHKERRQ(ierr); 831 ierr = ISDestroy(&IS_act);CHKERRQ(ierr); 832 833 ierr = ISGetLocalSize(keptrows,&cnt);CHKERRQ(ierr); 834 ierr = ISGetIndices(keptrows,&krows);CHKERRQ(ierr); 835 ierr = ISGetIndices(IS_inact,&inact);CHKERRQ(ierr); 836 ierr = PetscMalloc(cnt*sizeof(PetscInt),&nrows);CHKERRQ(ierr); 837 for (k=0; k<cnt; k++) { 838 nrows[k] = inact[krows[k]-rstart]; 839 } 840 ierr = ISRestoreIndices(keptrows,&krows);CHKERRQ(ierr); 841 ierr = ISRestoreIndices(IS_inact,&inact);CHKERRQ(ierr); 842 ierr = ISDestroy(&keptrows);CHKERRQ(ierr); 843 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 844 845 ierr = ISCreateGeneral(PETSC_COMM_WORLD,cnt,nrows,PETSC_OWN_POINTER,&IS_inact);CHKERRQ(ierr); 846 ierr = ISComplement(IS_inact,F->map->rstart,F->map->rend,&IS_act);CHKERRQ(ierr); 847 ierr = MatGetSubMatrix(snes->jacobian,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);CHKERRQ(ierr); 848 } 849 850 /* Get sizes of active and inactive sets */ 851 ierr = ISGetLocalSize(IS_act,&nis_act);CHKERRQ(ierr); 852 ierr = ISGetLocalSize(IS_inact,&nis_inact);CHKERRQ(ierr); 853 854 /* Create active and inactive set vectors */ 855 ierr = SNESVICreateSubVectors(snes,nis_inact,&F_inact);CHKERRQ(ierr); 856 ierr = SNESVICreateSubVectors(snes,nis_act,&Y_act);CHKERRQ(ierr); 857 ierr = SNESVICreateSubVectors(snes,nis_inact,&Y_inact);CHKERRQ(ierr); 858 859 /* Create scatter contexts */ 860 ierr = VecScatterCreate(Y,IS_act,Y_act,PETSC_NULL,&scat_act);CHKERRQ(ierr); 861 ierr = VecScatterCreate(Y,IS_inact,Y_inact,PETSC_NULL,&scat_inact);CHKERRQ(ierr); 862 863 /* Do a vec scatter to active and inactive set vectors */ 864 ierr = VecScatterBegin(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 865 ierr = VecScatterEnd(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 866 867 ierr = VecScatterBegin(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 868 ierr = VecScatterEnd(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 869 870 ierr = VecScatterBegin(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 871 ierr = VecScatterEnd(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 872 873 /* Active set direction = 0 */ 874 ierr = VecSet(Y_act,0);CHKERRQ(ierr); 875 if (snes->jacobian != snes->jacobian_pre) { 876 ierr = MatGetSubMatrix(snes->jacobian_pre,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&prejac_inact_inact);CHKERRQ(ierr); 877 } else prejac_inact_inact = jac_inact_inact; 878 879 ierr = ISEqual(vi->IS_inact_prev,IS_inact,&isequal);CHKERRQ(ierr); 880 if (!isequal) { 881 ierr = SNESVIResetPCandKSP(snes,jac_inact_inact,prejac_inact_inact);CHKERRQ(ierr); 882 } 883 884 /* ierr = ISView(IS_inact,0);CHKERRQ(ierr); */ 885 /* ierr = ISView(IS_act,0);CHKERRQ(ierr);*/ 886 /* ierr = MatView(snes->jacobian_pre,0); */ 887 888 ierr = KSPSetOperators(snes->ksp,jac_inact_inact,prejac_inact_inact,flg);CHKERRQ(ierr); 889 ierr = KSPSetUp(snes->ksp);CHKERRQ(ierr); 890 { 891 PC pc; 892 PetscBool flg; 893 ierr = KSPGetPC(snes->ksp,&pc);CHKERRQ(ierr); 894 ierr = PetscTypeCompare((PetscObject)pc,PCFIELDSPLIT,&flg);CHKERRQ(ierr); 895 if (flg) { 896 KSP *subksps; 897 ierr = PCFieldSplitGetSubKSP(pc,PETSC_NULL,&subksps);CHKERRQ(ierr); 898 ierr = KSPGetPC(subksps[0],&pc);CHKERRQ(ierr); 899 ierr = PetscFree(subksps);CHKERRQ(ierr); 900 ierr = PetscTypeCompare((PetscObject)pc,PCBJACOBI,&flg);CHKERRQ(ierr); 901 if (flg) { 902 PetscInt n,N = 101*101,j,cnts[3] = {0,0,0}; 903 const PetscInt *ii; 904 905 ierr = ISGetSize(IS_inact,&n);CHKERRQ(ierr); 906 ierr = ISGetIndices(IS_inact,&ii);CHKERRQ(ierr); 907 for (j=0; j<n; j++) { 908 if (ii[j] < N) cnts[0]++; 909 else if (ii[j] < 2*N) cnts[1]++; 910 else if (ii[j] < 3*N) cnts[2]++; 911 } 912 ierr = ISRestoreIndices(IS_inact,&ii);CHKERRQ(ierr); 913 914 ierr = PCBJacobiSetTotalBlocks(pc,3,cnts);CHKERRQ(ierr); 915 } 916 } 917 } 918 919 ierr = SNES_KSPSolve(snes,snes->ksp,F_inact,Y_inact);CHKERRQ(ierr); 920 ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr); 921 if (kspreason < 0) { 922 if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) { 923 ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr); 924 snes->reason = SNES_DIVERGED_LINEAR_SOLVE; 925 break; 926 } 927 } 928 929 ierr = VecScatterBegin(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 930 ierr = VecScatterEnd(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 931 ierr = VecScatterBegin(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 932 ierr = VecScatterEnd(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 933 934 ierr = VecDestroy(&F_inact);CHKERRQ(ierr); 935 ierr = VecDestroy(&Y_act);CHKERRQ(ierr); 936 ierr = VecDestroy(&Y_inact);CHKERRQ(ierr); 937 ierr = VecScatterDestroy(&scat_act);CHKERRQ(ierr); 938 ierr = VecScatterDestroy(&scat_inact);CHKERRQ(ierr); 939 ierr = ISDestroy(&IS_act);CHKERRQ(ierr); 940 if (!isequal) { 941 ierr = ISDestroy(&vi->IS_inact_prev);CHKERRQ(ierr); 942 ierr = ISDuplicate(IS_inact,&vi->IS_inact_prev);CHKERRQ(ierr); 943 } 944 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 945 ierr = MatDestroy(&jac_inact_inact);CHKERRQ(ierr); 946 if (snes->jacobian != snes->jacobian_pre) { 947 ierr = MatDestroy(&prejac_inact_inact);CHKERRQ(ierr); 948 } 949 ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr); 950 snes->linear_its += lits; 951 ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr); 952 /* 953 if (vi->precheckstep) { 954 PetscBool changed_y = PETSC_FALSE; 955 ierr = (*vi->precheckstep)(snes,X,Y,vi->precheck,&changed_y);CHKERRQ(ierr); 956 } 957 958 if (PetscLogPrintInfo){ 959 ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr); 960 } 961 */ 962 /* Compute a (scaled) negative update in the line search routine: 963 Y <- X - lambda*Y 964 and evaluate G = function(Y) (depends on the line search). 965 */ 966 ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr); 967 ynorm = 1; gnorm = fnorm; 968 ierr = (*vi->LineSearch)(snes,vi->lsP,X,F,G,Y,W,fnorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr); 969 ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",fnorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr); 970 if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break; 971 if (snes->domainerror) { 972 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 973 PetscFunctionReturn(0); 974 } 975 if (!lssucceed) { 976 if (++snes->numFailures >= snes->maxFailures) { 977 PetscBool ismin; 978 snes->reason = SNES_DIVERGED_LINE_SEARCH; 979 ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr); 980 if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN; 981 break; 982 } 983 } 984 /* Update function and solution vectors */ 985 fnorm = gnorm; 986 ierr = VecCopy(G,F);CHKERRQ(ierr); 987 ierr = VecCopy(W,X);CHKERRQ(ierr); 988 /* Monitor convergence */ 989 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 990 snes->iter = i+1; 991 snes->norm = fnorm; 992 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 993 SNESLogConvHistory(snes,snes->norm,lits); 994 ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr); 995 /* Test for convergence, xnorm = || X || */ 996 if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); } 997 ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 998 if (snes->reason) break; 999 } 1000 if (i == maxits) { 1001 ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr); 1002 if(!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT; 1003 } 1004 PetscFunctionReturn(0); 1005 } 1006 1007 #undef __FUNCT__ 1008 #define __FUNCT__ "SNESVISetRedundancyCheck" 1009 PetscErrorCode SNESVISetRedundancyCheck(SNES snes,PetscErrorCode (*func)(SNES,IS,IS*,void*),void *ctx) 1010 { 1011 SNES_VI *vi = (SNES_VI*)snes->data; 1012 1013 PetscFunctionBegin; 1014 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 1015 vi->checkredundancy = func; 1016 vi->ctxP = ctx; 1017 PetscFunctionReturn(0); 1018 } 1019 1020 #if defined(PETSC_HAVE_MATLAB_ENGINE) 1021 #include <engine.h> 1022 #include <mex.h> 1023 typedef struct {char *funcname; mxArray *ctx;} SNESMatlabContext; 1024 1025 #undef __FUNCT__ 1026 #define __FUNCT__ "SNESVIRedundancyCheck_Matlab" 1027 PetscErrorCode SNESVIRedundancyCheck_Matlab(SNES snes,IS is_act,IS* is_redact,void* ctx) 1028 { 1029 PetscErrorCode ierr; 1030 SNESMatlabContext *sctx = (SNESMatlabContext*)ctx; 1031 int nlhs = 1, nrhs = 5; 1032 mxArray *plhs[1], *prhs[5]; 1033 long long int l1 = 0, l2 = 0,ls = 0; 1034 PetscInt *indices=PETSC_NULL; 1035 1036 PetscFunctionBegin; 1037 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 1038 PetscValidHeaderSpecific(is_act,IS_CLASSID,2); 1039 PetscValidPointer(is_redact,3); 1040 PetscCheckSameComm(snes,1,is_act,2); 1041 1042 /* Create IS for reduced active set, its size and indices will be changed by the Matlab function */ 1043 ierr = ISCreateGeneral(((PetscObject)snes)->comm,0,indices,PETSC_OWN_POINTER,is_redact);CHKERRQ(ierr); 1044 /* call Matlab function in ctx */ 1045 ierr = PetscMemcpy(&ls,&snes,sizeof(snes));CHKERRQ(ierr); 1046 ierr = PetscMemcpy(&l1,&is_act,sizeof(is_act));CHKERRQ(ierr); 1047 ierr = PetscMemcpy(&l2,is_redact,sizeof(is_act));CHKERRQ(ierr); 1048 prhs[0] = mxCreateDoubleScalar((double)ls); 1049 prhs[1] = mxCreateDoubleScalar((double)l1); 1050 prhs[2] = mxCreateDoubleScalar((double)l2); 1051 prhs[3] = mxCreateString(sctx->funcname); 1052 prhs[4] = sctx->ctx; 1053 ierr = mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESVIRedundancyCheckInternal");CHKERRQ(ierr); 1054 ierr = mxGetScalar(plhs[0]);CHKERRQ(ierr); 1055 mxDestroyArray(prhs[0]); 1056 mxDestroyArray(prhs[1]); 1057 mxDestroyArray(prhs[2]); 1058 mxDestroyArray(prhs[3]); 1059 mxDestroyArray(plhs[0]); 1060 PetscFunctionReturn(0); 1061 } 1062 1063 #undef __FUNCT__ 1064 #define __FUNCT__ "SNESVISetRedundancyCheckMatlab" 1065 PetscErrorCode SNESVISetRedundancyCheckMatlab(SNES snes,const char* func,mxArray* ctx) 1066 { 1067 PetscErrorCode ierr; 1068 SNESMatlabContext *sctx; 1069 1070 PetscFunctionBegin; 1071 /* currently sctx is memory bleed */ 1072 ierr = PetscMalloc(sizeof(SNESMatlabContext),&sctx);CHKERRQ(ierr); 1073 ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr); 1074 sctx->ctx = mxDuplicateArray(ctx); 1075 ierr = SNESVISetRedundancyCheck(snes,SNESVIRedundancyCheck_Matlab,sctx);CHKERRQ(ierr); 1076 PetscFunctionReturn(0); 1077 } 1078 1079 #endif 1080 1081 1082 /* Variational Inequality solver using augmented space method. It does the opposite of the 1083 reduced space method i.e. it identifies the active set variables and instead of discarding 1084 them it augments the original system by introducing additional equality 1085 constraint equations for active set variables. The user can optionally provide an IS for 1086 a subset of 'redundant' active set variables which will treated as free variables. 1087 Specific implementation for Allen-Cahn problem 1088 */ 1089 #undef __FUNCT__ 1090 #define __FUNCT__ "SNESSolveVI_RS2" 1091 PetscErrorCode SNESSolveVI_RS2(SNES snes) 1092 { 1093 SNES_VI *vi = (SNES_VI*)snes->data; 1094 PetscErrorCode ierr; 1095 PetscInt maxits,i,lits; 1096 PetscBool lssucceed; 1097 MatStructure flg = DIFFERENT_NONZERO_PATTERN; 1098 PetscReal fnorm,gnorm,xnorm=0,ynorm; 1099 Vec Y,X,F,G,W; 1100 KSPConvergedReason kspreason; 1101 1102 PetscFunctionBegin; 1103 snes->numFailures = 0; 1104 snes->numLinearSolveFailures = 0; 1105 snes->reason = SNES_CONVERGED_ITERATING; 1106 1107 maxits = snes->max_its; /* maximum number of iterations */ 1108 X = snes->vec_sol; /* solution vector */ 1109 F = snes->vec_func; /* residual vector */ 1110 Y = snes->work[0]; /* work vectors */ 1111 G = snes->work[1]; 1112 W = snes->work[2]; 1113 1114 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1115 snes->iter = 0; 1116 snes->norm = 0.0; 1117 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1118 1119 ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr); 1120 ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr); 1121 if (snes->domainerror) { 1122 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 1123 PetscFunctionReturn(0); 1124 } 1125 ierr = SNESVIComputeInactiveSetFnorm(snes,F,X,&fnorm);CHKERRQ(ierr); 1126 ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr); /* xnorm <- ||x|| */ 1127 ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr); 1128 if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1129 1130 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1131 snes->norm = fnorm; 1132 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1133 SNESLogConvHistory(snes,fnorm,0); 1134 ierr = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr); 1135 1136 /* set parameter for default relative tolerance convergence test */ 1137 snes->ttol = fnorm*snes->rtol; 1138 /* test convergence */ 1139 ierr = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1140 if (snes->reason) PetscFunctionReturn(0); 1141 1142 for (i=0; i<maxits; i++) { 1143 IS IS_act,IS_inact; /* _act -> active set _inact -> inactive set */ 1144 IS IS_redact; /* redundant active set */ 1145 Mat J_aug,Jpre_aug; 1146 Vec F_aug,Y_aug; 1147 PetscInt nis_redact,nis_act; 1148 const PetscInt *idx_redact,*idx_act; 1149 PetscInt k; 1150 PetscInt *idx_actkept=PETSC_NULL,nkept; /* list of kept active set */ 1151 PetscScalar *f,*f2; 1152 PetscBool isequal; 1153 PetscInt i1=0,j1=0; 1154 1155 /* Call general purpose update function */ 1156 if (snes->ops->update) { 1157 ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr); 1158 } 1159 ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr); 1160 1161 /* Create active and inactive index sets */ 1162 ierr = SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&IS_inact);CHKERRQ(ierr); 1163 1164 /* Get local active set size */ 1165 ierr = ISGetLocalSize(IS_act,&nis_act);CHKERRQ(ierr); 1166 ierr = ISGetIndices(IS_act,&idx_act);CHKERRQ(ierr); 1167 if(nis_act) { 1168 if(vi->checkredundancy) { 1169 (*vi->checkredundancy)(snes,IS_act,&IS_redact,vi->ctxP); 1170 } 1171 1172 if(!IS_redact) { 1173 /* User called checkredundancy function but didn't create IS_redact because 1174 there were no redundant active set variables */ 1175 /* Copy over all active set indices to the list */ 1176 ierr = PetscMalloc(nis_act*sizeof(PetscInt),&idx_actkept);CHKERRQ(ierr); 1177 for(k=0;k < nis_act;k++) idx_actkept[k] = idx_act[k]; 1178 nkept = nis_act; 1179 } else { 1180 ierr = ISGetLocalSize(IS_redact,&nis_redact);CHKERRQ(ierr); 1181 ierr = PetscMalloc((nis_act-nis_redact)*sizeof(PetscInt),&idx_actkept);CHKERRQ(ierr); 1182 1183 /* Create reduced active set list */ 1184 ierr = ISGetIndices(IS_act,&idx_act);CHKERRQ(ierr); 1185 ierr = ISGetIndices(IS_redact,&idx_redact);CHKERRQ(ierr); 1186 j1 = 0;nkept = 0; 1187 for(k=0;k<nis_act;k++) { 1188 if(j1 < nis_redact && idx_act[k] == idx_redact[j1]) j1++; 1189 else idx_actkept[nkept++] = idx_act[k]; 1190 } 1191 ierr = ISRestoreIndices(IS_act,&idx_act);CHKERRQ(ierr); 1192 ierr = ISRestoreIndices(IS_redact,&idx_redact);CHKERRQ(ierr); 1193 1194 ierr = ISDestroy(&IS_redact);CHKERRQ(ierr); 1195 } 1196 1197 /* Create augmented F and Y */ 1198 ierr = VecCreate(((PetscObject)snes)->comm,&F_aug);CHKERRQ(ierr); 1199 ierr = VecSetSizes(F_aug,F->map->n+nkept,PETSC_DECIDE);CHKERRQ(ierr); 1200 ierr = VecSetFromOptions(F_aug);CHKERRQ(ierr); 1201 ierr = VecDuplicate(F_aug,&Y_aug);CHKERRQ(ierr); 1202 1203 /* Copy over F to F_aug in the first n locations */ 1204 ierr = VecGetArray(F,&f);CHKERRQ(ierr); 1205 ierr = VecGetArray(F_aug,&f2);CHKERRQ(ierr); 1206 ierr = PetscMemcpy(f2,f,F->map->n*sizeof(PetscScalar));CHKERRQ(ierr); 1207 ierr = VecRestoreArray(F,&f);CHKERRQ(ierr); 1208 ierr = VecRestoreArray(F_aug,&f2);CHKERRQ(ierr); 1209 1210 /* Create the augmented jacobian matrix */ 1211 ierr = MatCreate(((PetscObject)snes)->comm,&J_aug);CHKERRQ(ierr); 1212 ierr = MatSetSizes(J_aug,X->map->n+nkept,X->map->n+nkept,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr); 1213 ierr = MatSetFromOptions(J_aug);CHKERRQ(ierr); 1214 1215 1216 { /* local vars */ 1217 /* Preallocate augmented matrix and set values in it...Doing only sequential case first*/ 1218 PetscInt ncols; 1219 const PetscInt *cols; 1220 const PetscScalar *vals; 1221 PetscScalar value=1.0; 1222 PetscInt row,col; 1223 PetscInt *d_nnz; 1224 1225 ierr = PetscMalloc((X->map->n+nkept)*sizeof(PetscInt),&d_nnz);CHKERRQ(ierr); 1226 ierr = PetscMemzero(d_nnz,(X->map->n+nkept)*sizeof(PetscInt));CHKERRQ(ierr); 1227 for(row=0;row<snes->jacobian->rmap->n;row++) { 1228 ierr = MatGetRow(snes->jacobian,row,&ncols,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr); 1229 d_nnz[row] += ncols; 1230 ierr = MatRestoreRow(snes->jacobian,row,&ncols,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr); 1231 } 1232 1233 for(k=0;k<nkept;k++) { 1234 d_nnz[idx_actkept[k]] += 1; 1235 d_nnz[snes->jacobian->rmap->n+k] += 1; 1236 } 1237 ierr = MatSeqAIJSetPreallocation(J_aug,PETSC_NULL,d_nnz);CHKERRQ(ierr); 1238 1239 ierr = PetscFree(d_nnz);CHKERRQ(ierr); 1240 1241 /* Set the original jacobian matrix in J_aug */ 1242 for(row=0;row<snes->jacobian->rmap->n;row++) { 1243 ierr = MatGetRow(snes->jacobian,row,&ncols,&cols,&vals);CHKERRQ(ierr); 1244 ierr = MatSetValues(J_aug,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr); 1245 ierr = MatRestoreRow(snes->jacobian,row,&ncols,&cols,&vals);CHKERRQ(ierr); 1246 } 1247 /* Add the augmented part */ 1248 for(k=0;k<nkept;k++) { 1249 row = idx_actkept[k]; 1250 col = snes->jacobian->rmap->n+k; 1251 ierr = MatSetValues(J_aug,1,&row,1,&col,&value,INSERT_VALUES);CHKERRQ(ierr); 1252 ierr = MatSetValues(J_aug,1,&col,1,&row,&value,INSERT_VALUES);CHKERRQ(ierr); 1253 } 1254 ierr = MatAssemblyBegin(J_aug,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 1255 ierr = MatAssemblyEnd(J_aug,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 1256 /* Only considering prejac = jac for now */ 1257 Jpre_aug = J_aug; 1258 } /* local vars*/ 1259 } else { 1260 F_aug = F; J_aug = snes->jacobian; Y_aug = Y; Jpre_aug = snes->jacobian_pre; 1261 } 1262 1263 ierr = ISEqual(vi->IS_inact_prev,IS_inact,&isequal);CHKERRQ(ierr); 1264 if (!isequal) { 1265 ierr = SNESVIResetPCandKSP(snes,J_aug,Jpre_aug);CHKERRQ(ierr); 1266 } 1267 ierr = KSPSetOperators(snes->ksp,J_aug,Jpre_aug,flg);CHKERRQ(ierr); 1268 ierr = KSPSetUp(snes->ksp);CHKERRQ(ierr); 1269 /* { 1270 PC pc; 1271 PetscBool flg; 1272 ierr = KSPGetPC(snes->ksp,&pc);CHKERRQ(ierr); 1273 ierr = PetscTypeCompare((PetscObject)pc,PCFIELDSPLIT,&flg);CHKERRQ(ierr); 1274 if (flg) { 1275 KSP *subksps; 1276 ierr = PCFieldSplitGetSubKSP(pc,PETSC_NULL,&subksps);CHKERRQ(ierr); 1277 ierr = KSPGetPC(subksps[0],&pc);CHKERRQ(ierr); 1278 ierr = PetscFree(subksps);CHKERRQ(ierr); 1279 ierr = PetscTypeCompare((PetscObject)pc,PCBJACOBI,&flg);CHKERRQ(ierr); 1280 if (flg) { 1281 PetscInt n,N = 101*101,j,cnts[3] = {0,0,0}; 1282 const PetscInt *ii; 1283 1284 ierr = ISGetSize(IS_inact,&n);CHKERRQ(ierr); 1285 ierr = ISGetIndices(IS_inact,&ii);CHKERRQ(ierr); 1286 for (j=0; j<n; j++) { 1287 if (ii[j] < N) cnts[0]++; 1288 else if (ii[j] < 2*N) cnts[1]++; 1289 else if (ii[j] < 3*N) cnts[2]++; 1290 } 1291 ierr = ISRestoreIndices(IS_inact,&ii);CHKERRQ(ierr); 1292 1293 ierr = PCBJacobiSetTotalBlocks(pc,3,cnts);CHKERRQ(ierr); 1294 } 1295 } 1296 } 1297 */ 1298 ierr = SNES_KSPSolve(snes,snes->ksp,F_aug,Y_aug);CHKERRQ(ierr); 1299 ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr); 1300 if (kspreason < 0) { 1301 if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) { 1302 ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr); 1303 snes->reason = SNES_DIVERGED_LINEAR_SOLVE; 1304 break; 1305 } 1306 } 1307 1308 if(nis_act) { 1309 PetscScalar *y1,*y2; 1310 ierr = VecGetArray(Y,&y1);CHKERRQ(ierr); 1311 ierr = VecGetArray(Y_aug,&y2);CHKERRQ(ierr); 1312 /* Copy over inactive Y_aug to Y */ 1313 j1 = 0; 1314 for(i1=Y->map->rstart;i1 < Y->map->rend;i1++) { 1315 if(j1 < nkept && idx_actkept[j1] == i1) j1++; 1316 else y1[i1-Y->map->rstart] = y2[i1-Y->map->rstart]; 1317 } 1318 ierr = VecRestoreArray(Y,&y1);CHKERRQ(ierr); 1319 ierr = VecRestoreArray(Y_aug,&y2);CHKERRQ(ierr); 1320 1321 ierr = VecDestroy(&F_aug);CHKERRQ(ierr); 1322 ierr = VecDestroy(&Y_aug);CHKERRQ(ierr); 1323 ierr = MatDestroy(&J_aug);CHKERRQ(ierr); 1324 ierr = PetscFree(idx_actkept);CHKERRQ(ierr); 1325 } 1326 1327 if (!isequal) { 1328 ierr = ISDestroy(&vi->IS_inact_prev);CHKERRQ(ierr); 1329 ierr = ISDuplicate(IS_inact,&vi->IS_inact_prev);CHKERRQ(ierr); 1330 } 1331 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 1332 1333 ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr); 1334 snes->linear_its += lits; 1335 ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr); 1336 /* 1337 if (vi->precheckstep) { 1338 PetscBool changed_y = PETSC_FALSE; 1339 ierr = (*vi->precheckstep)(snes,X,Y,vi->precheck,&changed_y);CHKERRQ(ierr); 1340 } 1341 1342 if (PetscLogPrintInfo){ 1343 ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr); 1344 } 1345 */ 1346 /* Compute a (scaled) negative update in the line search routine: 1347 Y <- X - lambda*Y 1348 and evaluate G = function(Y) (depends on the line search). 1349 */ 1350 ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr); 1351 ynorm = 1; gnorm = fnorm; 1352 ierr = (*vi->LineSearch)(snes,vi->lsP,X,F,G,Y,W,fnorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr); 1353 ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",fnorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr); 1354 if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break; 1355 if (snes->domainerror) { 1356 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 1357 PetscFunctionReturn(0); 1358 } 1359 if (!lssucceed) { 1360 if (++snes->numFailures >= snes->maxFailures) { 1361 PetscBool ismin; 1362 snes->reason = SNES_DIVERGED_LINE_SEARCH; 1363 ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr); 1364 if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN; 1365 break; 1366 } 1367 } 1368 /* Update function and solution vectors */ 1369 fnorm = gnorm; 1370 ierr = VecCopy(G,F);CHKERRQ(ierr); 1371 ierr = VecCopy(W,X);CHKERRQ(ierr); 1372 /* Monitor convergence */ 1373 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1374 snes->iter = i+1; 1375 snes->norm = fnorm; 1376 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1377 SNESLogConvHistory(snes,snes->norm,lits); 1378 ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr); 1379 /* Test for convergence, xnorm = || X || */ 1380 if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); } 1381 ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1382 if (snes->reason) break; 1383 } 1384 if (i == maxits) { 1385 ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr); 1386 if(!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT; 1387 } 1388 PetscFunctionReturn(0); 1389 } 1390 1391 /* -------------------------------------------------------------------------- */ 1392 /* 1393 SNESSetUp_VI - Sets up the internal data structures for the later use 1394 of the SNESVI nonlinear solver. 1395 1396 Input Parameter: 1397 . snes - the SNES context 1398 . x - the solution vector 1399 1400 Application Interface Routine: SNESSetUp() 1401 1402 Notes: 1403 For basic use of the SNES solvers, the user need not explicitly call 1404 SNESSetUp(), since these actions will automatically occur during 1405 the call to SNESSolve(). 1406 */ 1407 #undef __FUNCT__ 1408 #define __FUNCT__ "SNESSetUp_VI" 1409 PetscErrorCode SNESSetUp_VI(SNES snes) 1410 { 1411 PetscErrorCode ierr; 1412 SNES_VI *vi = (SNES_VI*) snes->data; 1413 PetscInt i_start[3],i_end[3]; 1414 1415 PetscFunctionBegin; 1416 1417 ierr = SNESDefaultGetWork(snes,3);CHKERRQ(ierr); 1418 1419 /* If the lower and upper bound on variables are not set, set it to 1420 -Inf and Inf */ 1421 if (!vi->xl && !vi->xu) { 1422 vi->usersetxbounds = PETSC_FALSE; 1423 ierr = VecDuplicate(snes->vec_sol, &vi->xl); CHKERRQ(ierr); 1424 ierr = VecSet(vi->xl,PETSC_VI_NINF);CHKERRQ(ierr); 1425 ierr = VecDuplicate(snes->vec_sol, &vi->xu); CHKERRQ(ierr); 1426 ierr = VecSet(vi->xu,PETSC_VI_INF);CHKERRQ(ierr); 1427 } else { 1428 /* Check if lower bound, upper bound and solution vector distribution across the processors is identical */ 1429 ierr = VecGetOwnershipRange(snes->vec_sol,i_start,i_end);CHKERRQ(ierr); 1430 ierr = VecGetOwnershipRange(vi->xl,i_start+1,i_end+1);CHKERRQ(ierr); 1431 ierr = VecGetOwnershipRange(vi->xu,i_start+2,i_end+2);CHKERRQ(ierr); 1432 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])) 1433 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."); 1434 } 1435 if (snes->ops->solve != SNESSolveVI_SS) { 1436 /* Set up previous active index set for the first snes solve 1437 vi->IS_inact_prev = 0,1,2,....N */ 1438 PetscInt *indices; 1439 PetscInt i,n,rstart,rend; 1440 1441 ierr = VecGetOwnershipRange(snes->vec_sol,&rstart,&rend);CHKERRQ(ierr); 1442 ierr = VecGetLocalSize(snes->vec_sol,&n);CHKERRQ(ierr); 1443 ierr = PetscMalloc(n*sizeof(PetscInt),&indices);CHKERRQ(ierr); 1444 for(i=0;i < n; i++) indices[i] = rstart + i; 1445 ierr = ISCreateGeneral(((PetscObject)snes)->comm,n,indices,PETSC_OWN_POINTER,&vi->IS_inact_prev); 1446 } 1447 1448 if (snes->ops->solve == SNESSolveVI_SS) { 1449 ierr = VecDuplicate(snes->vec_sol, &vi->dpsi);CHKERRQ(ierr); 1450 ierr = VecDuplicate(snes->vec_sol, &vi->phi); CHKERRQ(ierr); 1451 ierr = VecDuplicate(snes->vec_sol, &vi->Da); CHKERRQ(ierr); 1452 ierr = VecDuplicate(snes->vec_sol, &vi->Db); CHKERRQ(ierr); 1453 ierr = VecDuplicate(snes->vec_sol, &vi->z);CHKERRQ(ierr); 1454 ierr = VecDuplicate(snes->vec_sol, &vi->t); CHKERRQ(ierr); 1455 } 1456 PetscFunctionReturn(0); 1457 } 1458 /* -------------------------------------------------------------------------- */ 1459 /* 1460 SNESDestroy_VI - Destroys the private SNES_VI context that was created 1461 with SNESCreate_VI(). 1462 1463 Input Parameter: 1464 . snes - the SNES context 1465 1466 Application Interface Routine: SNESDestroy() 1467 */ 1468 #undef __FUNCT__ 1469 #define __FUNCT__ "SNESDestroy_VI" 1470 PetscErrorCode SNESDestroy_VI(SNES snes) 1471 { 1472 SNES_VI *vi = (SNES_VI*) snes->data; 1473 PetscErrorCode ierr; 1474 1475 PetscFunctionBegin; 1476 if (snes->ops->solve != SNESSolveVI_SS) { 1477 ierr = ISDestroy(&vi->IS_inact_prev); 1478 } 1479 1480 if (snes->ops->solve == SNESSolveVI_SS) { 1481 /* clear vectors */ 1482 ierr = VecDestroy(&vi->dpsi);CHKERRQ(ierr); 1483 ierr = VecDestroy(&vi->phi); CHKERRQ(ierr); 1484 ierr = VecDestroy(&vi->Da); CHKERRQ(ierr); 1485 ierr = VecDestroy(&vi->Db); CHKERRQ(ierr); 1486 ierr = VecDestroy(&vi->z); CHKERRQ(ierr); 1487 ierr = VecDestroy(&vi->t); CHKERRQ(ierr); 1488 } 1489 1490 if (!vi->usersetxbounds) { 1491 ierr = VecDestroy(&vi->xl); CHKERRQ(ierr); 1492 ierr = VecDestroy(&vi->xu); CHKERRQ(ierr); 1493 } 1494 1495 ierr = PetscViewerASCIIMonitorDestroy(&vi->lsmonitor);CHKERRQ(ierr); 1496 ierr = PetscFree(snes->data);CHKERRQ(ierr); 1497 1498 /* clear composed functions */ 1499 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSet_C","",PETSC_NULL);CHKERRQ(ierr); 1500 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSetMonitor_C","",PETSC_NULL);CHKERRQ(ierr); 1501 PetscFunctionReturn(0); 1502 } 1503 1504 /* -------------------------------------------------------------------------- */ 1505 #undef __FUNCT__ 1506 #define __FUNCT__ "SNESLineSearchNo_VI" 1507 1508 /* 1509 This routine does not actually do a line search but it takes a full newton 1510 step while ensuring that the new iterates remain within the constraints. 1511 1512 */ 1513 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) 1514 { 1515 PetscErrorCode ierr; 1516 SNES_VI *vi = (SNES_VI*)snes->data; 1517 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1518 1519 PetscFunctionBegin; 1520 *flag = PETSC_TRUE; 1521 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1522 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); /* ynorm = || y || */ 1523 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1524 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1525 if (vi->postcheckstep) { 1526 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1527 } 1528 if (changed_y) { 1529 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1530 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1531 } 1532 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1533 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1534 if (!snes->domainerror) { 1535 if (snes->ops->solve != SNESSolveVI_SS) { 1536 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1537 } else { 1538 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); /* gnorm = || g || */ 1539 } 1540 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1541 } 1542 if (vi->lsmonitor) { 1543 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1544 } 1545 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1546 PetscFunctionReturn(0); 1547 } 1548 1549 /* -------------------------------------------------------------------------- */ 1550 #undef __FUNCT__ 1551 #define __FUNCT__ "SNESLineSearchNoNorms_VI" 1552 1553 /* 1554 This routine is a copy of SNESLineSearchNoNorms in snes/impls/ls/ls.c 1555 */ 1556 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) 1557 { 1558 PetscErrorCode ierr; 1559 SNES_VI *vi = (SNES_VI*)snes->data; 1560 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1561 1562 PetscFunctionBegin; 1563 *flag = PETSC_TRUE; 1564 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1565 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1566 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1567 if (vi->postcheckstep) { 1568 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1569 } 1570 if (changed_y) { 1571 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1572 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1573 } 1574 1575 /* don't evaluate function the last time through */ 1576 if (snes->iter < snes->max_its-1) { 1577 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1578 } 1579 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1580 PetscFunctionReturn(0); 1581 } 1582 1583 /* -------------------------------------------------------------------------- */ 1584 #undef __FUNCT__ 1585 #define __FUNCT__ "SNESLineSearchCubic_VI" 1586 /* 1587 This routine implements a cubic line search while doing a projection on the variable bounds 1588 */ 1589 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) 1590 { 1591 PetscReal initslope,lambdaprev,gnormprev,a,b,d,t1,t2,rellength; 1592 PetscReal minlambda,lambda,lambdatemp; 1593 #if defined(PETSC_USE_COMPLEX) 1594 PetscScalar cinitslope; 1595 #endif 1596 PetscErrorCode ierr; 1597 PetscInt count; 1598 SNES_VI *vi = (SNES_VI*)snes->data; 1599 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1600 MPI_Comm comm; 1601 1602 PetscFunctionBegin; 1603 ierr = PetscObjectGetComm((PetscObject)snes,&comm);CHKERRQ(ierr); 1604 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1605 *flag = PETSC_TRUE; 1606 1607 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); 1608 if (*ynorm == 0.0) { 1609 if (vi->lsmonitor) { 1610 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Initial direction and size is 0\n");CHKERRQ(ierr); 1611 } 1612 *gnorm = fnorm; 1613 ierr = VecCopy(x,w);CHKERRQ(ierr); 1614 ierr = VecCopy(f,g);CHKERRQ(ierr); 1615 *flag = PETSC_FALSE; 1616 goto theend1; 1617 } 1618 if (*ynorm > vi->maxstep) { /* Step too big, so scale back */ 1619 if (vi->lsmonitor) { 1620 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Scaling step by %G old ynorm %G\n",vi->maxstep/(*ynorm),*ynorm);CHKERRQ(ierr); 1621 } 1622 ierr = VecScale(y,vi->maxstep/(*ynorm));CHKERRQ(ierr); 1623 *ynorm = vi->maxstep; 1624 } 1625 ierr = VecMaxPointwiseDivide(y,x,&rellength);CHKERRQ(ierr); 1626 minlambda = vi->minlambda/rellength; 1627 ierr = MatMult(snes->jacobian,y,w);CHKERRQ(ierr); 1628 #if defined(PETSC_USE_COMPLEX) 1629 ierr = VecDot(f,w,&cinitslope);CHKERRQ(ierr); 1630 initslope = PetscRealPart(cinitslope); 1631 #else 1632 ierr = VecDot(f,w,&initslope);CHKERRQ(ierr); 1633 #endif 1634 if (initslope > 0.0) initslope = -initslope; 1635 if (initslope == 0.0) initslope = -1.0; 1636 1637 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1638 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1639 if (snes->nfuncs >= snes->max_funcs) { 1640 ierr = PetscInfo(snes,"Exceeded maximum function evaluations, while checking full step length!\n");CHKERRQ(ierr); 1641 *flag = PETSC_FALSE; 1642 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1643 goto theend1; 1644 } 1645 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1646 if (snes->ops->solve != SNESSolveVI_SS) { 1647 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1648 } else { 1649 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1650 } 1651 if (snes->domainerror) { 1652 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1653 PetscFunctionReturn(0); 1654 } 1655 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1656 ierr = PetscInfo2(snes,"Initial fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1657 if (.5*(*gnorm)*(*gnorm) <= .5*fnorm*fnorm + vi->alpha*initslope) { /* Sufficient reduction */ 1658 if (vi->lsmonitor) { 1659 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1660 } 1661 goto theend1; 1662 } 1663 1664 /* Fit points with quadratic */ 1665 lambda = 1.0; 1666 lambdatemp = -initslope/((*gnorm)*(*gnorm) - fnorm*fnorm - 2.0*initslope); 1667 lambdaprev = lambda; 1668 gnormprev = *gnorm; 1669 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 1670 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 1671 else lambda = lambdatemp; 1672 1673 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 1674 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1675 if (snes->nfuncs >= snes->max_funcs) { 1676 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while attempting quadratic backtracking! %D \n",snes->nfuncs);CHKERRQ(ierr); 1677 *flag = PETSC_FALSE; 1678 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1679 goto theend1; 1680 } 1681 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1682 if (snes->ops->solve != SNESSolveVI_SS) { 1683 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1684 } else { 1685 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1686 } 1687 if (snes->domainerror) { 1688 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1689 PetscFunctionReturn(0); 1690 } 1691 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1692 if (vi->lsmonitor) { 1693 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: gnorm after quadratic fit %G\n",*gnorm);CHKERRQ(ierr); 1694 } 1695 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* sufficient reduction */ 1696 if (vi->lsmonitor) { 1697 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Quadratically determined step, lambda=%18.16e\n",lambda);CHKERRQ(ierr); 1698 } 1699 goto theend1; 1700 } 1701 1702 /* Fit points with cubic */ 1703 count = 1; 1704 while (PETSC_TRUE) { 1705 if (lambda <= minlambda) { 1706 if (vi->lsmonitor) { 1707 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: unable to find good step length! After %D tries \n",count);CHKERRQ(ierr); 1708 ierr = PetscViewerASCIIMonitorPrintf(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); 1709 } 1710 *flag = PETSC_FALSE; 1711 break; 1712 } 1713 t1 = .5*((*gnorm)*(*gnorm) - fnorm*fnorm) - lambda*initslope; 1714 t2 = .5*(gnormprev*gnormprev - fnorm*fnorm) - lambdaprev*initslope; 1715 a = (t1/(lambda*lambda) - t2/(lambdaprev*lambdaprev))/(lambda-lambdaprev); 1716 b = (-lambdaprev*t1/(lambda*lambda) + lambda*t2/(lambdaprev*lambdaprev))/(lambda-lambdaprev); 1717 d = b*b - 3*a*initslope; 1718 if (d < 0.0) d = 0.0; 1719 if (a == 0.0) { 1720 lambdatemp = -initslope/(2.0*b); 1721 } else { 1722 lambdatemp = (-b + sqrt(d))/(3.0*a); 1723 } 1724 lambdaprev = lambda; 1725 gnormprev = *gnorm; 1726 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 1727 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 1728 else lambda = lambdatemp; 1729 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 1730 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1731 if (snes->nfuncs >= snes->max_funcs) { 1732 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while looking for good step length! %D \n",count);CHKERRQ(ierr); 1733 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); 1734 *flag = PETSC_FALSE; 1735 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1736 break; 1737 } 1738 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1739 if (snes->ops->solve != SNESSolveVI_SS) { 1740 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1741 } else { 1742 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1743 } 1744 if (snes->domainerror) { 1745 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1746 PetscFunctionReturn(0); 1747 } 1748 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1749 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* is reduction enough? */ 1750 if (vi->lsmonitor) { 1751 ierr = PetscPrintf(comm," Line search: Cubically determined step, current gnorm %G lambda=%18.16e\n",*gnorm,lambda);CHKERRQ(ierr); 1752 } 1753 break; 1754 } else { 1755 if (vi->lsmonitor) { 1756 ierr = PetscPrintf(comm," Line search: Cubic step no good, shrinking lambda, current gnorm %G lambda=%18.16e\n",*gnorm,lambda);CHKERRQ(ierr); 1757 } 1758 } 1759 count++; 1760 } 1761 theend1: 1762 /* Optional user-defined check for line search step validity */ 1763 if (vi->postcheckstep && *flag) { 1764 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1765 if (changed_y) { 1766 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1767 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1768 } 1769 if (changed_y || changed_w) { /* recompute the function if the step has changed */ 1770 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1771 if (snes->ops->solve != SNESSolveVI_SS) { 1772 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1773 } else { 1774 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1775 } 1776 if (snes->domainerror) { 1777 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1778 PetscFunctionReturn(0); 1779 } 1780 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1781 ierr = VecNormBegin(y,NORM_2,ynorm);CHKERRQ(ierr); 1782 ierr = VecNormEnd(y,NORM_2,ynorm);CHKERRQ(ierr); 1783 } 1784 } 1785 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1786 PetscFunctionReturn(0); 1787 } 1788 1789 #undef __FUNCT__ 1790 #define __FUNCT__ "SNESLineSearchQuadratic_VI" 1791 /* 1792 This routine does a quadratic line search while keeping the iterates within the variable bounds 1793 */ 1794 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) 1795 { 1796 /* 1797 Note that for line search purposes we work with with the related 1798 minimization problem: 1799 min z(x): R^n -> R, 1800 where z(x) = .5 * fnorm*fnorm,and fnorm = || f ||_2. 1801 */ 1802 PetscReal initslope,minlambda,lambda,lambdatemp,rellength; 1803 #if defined(PETSC_USE_COMPLEX) 1804 PetscScalar cinitslope; 1805 #endif 1806 PetscErrorCode ierr; 1807 PetscInt count; 1808 SNES_VI *vi = (SNES_VI*)snes->data; 1809 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1810 1811 PetscFunctionBegin; 1812 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1813 *flag = PETSC_TRUE; 1814 1815 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); 1816 if (*ynorm == 0.0) { 1817 if (vi->lsmonitor) { 1818 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor,"Line search: Direction and size is 0\n");CHKERRQ(ierr); 1819 } 1820 *gnorm = fnorm; 1821 ierr = VecCopy(x,w);CHKERRQ(ierr); 1822 ierr = VecCopy(f,g);CHKERRQ(ierr); 1823 *flag = PETSC_FALSE; 1824 goto theend2; 1825 } 1826 if (*ynorm > vi->maxstep) { /* Step too big, so scale back */ 1827 ierr = VecScale(y,vi->maxstep/(*ynorm));CHKERRQ(ierr); 1828 *ynorm = vi->maxstep; 1829 } 1830 ierr = VecMaxPointwiseDivide(y,x,&rellength);CHKERRQ(ierr); 1831 minlambda = vi->minlambda/rellength; 1832 ierr = MatMult(snes->jacobian,y,w);CHKERRQ(ierr); 1833 #if defined(PETSC_USE_COMPLEX) 1834 ierr = VecDot(f,w,&cinitslope);CHKERRQ(ierr); 1835 initslope = PetscRealPart(cinitslope); 1836 #else 1837 ierr = VecDot(f,w,&initslope);CHKERRQ(ierr); 1838 #endif 1839 if (initslope > 0.0) initslope = -initslope; 1840 if (initslope == 0.0) initslope = -1.0; 1841 ierr = PetscInfo1(snes,"Initslope %G \n",initslope);CHKERRQ(ierr); 1842 1843 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1844 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1845 if (snes->nfuncs >= snes->max_funcs) { 1846 ierr = PetscInfo(snes,"Exceeded maximum function evaluations, while checking full step length!\n");CHKERRQ(ierr); 1847 *flag = PETSC_FALSE; 1848 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1849 goto theend2; 1850 } 1851 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1852 if (snes->ops->solve != SNESSolveVI_SS) { 1853 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1854 } else { 1855 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1856 } 1857 if (snes->domainerror) { 1858 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1859 PetscFunctionReturn(0); 1860 } 1861 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1862 if (.5*(*gnorm)*(*gnorm) <= .5*fnorm*fnorm + vi->alpha*initslope) { /* Sufficient reduction */ 1863 if (vi->lsmonitor) { 1864 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1865 } 1866 goto theend2; 1867 } 1868 1869 /* Fit points with quadratic */ 1870 lambda = 1.0; 1871 count = 1; 1872 while (PETSC_TRUE) { 1873 if (lambda <= minlambda) { /* bad luck; use full step */ 1874 if (vi->lsmonitor) { 1875 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor,"Line search: Unable to find good step length! %D \n",count);CHKERRQ(ierr); 1876 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor,"Line search: fnorm=%G, gnorm=%G, ynorm=%G, lambda=%G, initial slope=%G\n",fnorm,*gnorm,*ynorm,lambda,initslope);CHKERRQ(ierr); 1877 } 1878 ierr = VecCopy(x,w);CHKERRQ(ierr); 1879 *flag = PETSC_FALSE; 1880 break; 1881 } 1882 lambdatemp = -initslope/((*gnorm)*(*gnorm) - fnorm*fnorm - 2.0*initslope); 1883 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 1884 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 1885 else lambda = lambdatemp; 1886 1887 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 1888 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1889 if (snes->nfuncs >= snes->max_funcs) { 1890 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while looking for good step length! %D \n",count);CHKERRQ(ierr); 1891 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); 1892 *flag = PETSC_FALSE; 1893 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1894 break; 1895 } 1896 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1897 if (snes->domainerror) { 1898 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1899 PetscFunctionReturn(0); 1900 } 1901 if (snes->ops->solve != SNESSolveVI_SS) { 1902 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1903 } else { 1904 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1905 } 1906 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1907 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* sufficient reduction */ 1908 if (vi->lsmonitor) { 1909 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line Search: Quadratically determined step, lambda=%G\n",lambda);CHKERRQ(ierr); 1910 } 1911 break; 1912 } 1913 count++; 1914 } 1915 theend2: 1916 /* Optional user-defined check for line search step validity */ 1917 if (vi->postcheckstep) { 1918 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1919 if (changed_y) { 1920 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1921 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1922 } 1923 if (changed_y || changed_w) { /* recompute the function if the step has changed */ 1924 ierr = SNESComputeFunction(snes,w,g); 1925 if (snes->domainerror) { 1926 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1927 PetscFunctionReturn(0); 1928 } 1929 if (snes->ops->solve != SNESSolveVI_SS) { 1930 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1931 } else { 1932 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1933 } 1934 1935 ierr = VecNormBegin(y,NORM_2,ynorm);CHKERRQ(ierr); 1936 ierr = VecNormEnd(y,NORM_2,ynorm);CHKERRQ(ierr); 1937 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1938 } 1939 } 1940 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1941 PetscFunctionReturn(0); 1942 } 1943 1944 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*/ 1945 /* -------------------------------------------------------------------------- */ 1946 EXTERN_C_BEGIN 1947 #undef __FUNCT__ 1948 #define __FUNCT__ "SNESLineSearchSet_VI" 1949 PetscErrorCode SNESLineSearchSet_VI(SNES snes,FCN2 func,void *lsctx) 1950 { 1951 PetscFunctionBegin; 1952 ((SNES_VI *)(snes->data))->LineSearch = func; 1953 ((SNES_VI *)(snes->data))->lsP = lsctx; 1954 PetscFunctionReturn(0); 1955 } 1956 EXTERN_C_END 1957 1958 /* -------------------------------------------------------------------------- */ 1959 EXTERN_C_BEGIN 1960 #undef __FUNCT__ 1961 #define __FUNCT__ "SNESLineSearchSetMonitor_VI" 1962 PetscErrorCode SNESLineSearchSetMonitor_VI(SNES snes,PetscBool flg) 1963 { 1964 SNES_VI *vi = (SNES_VI*)snes->data; 1965 PetscErrorCode ierr; 1966 1967 PetscFunctionBegin; 1968 if (flg && !vi->lsmonitor) { 1969 ierr = PetscViewerASCIIMonitorCreate(((PetscObject)snes)->comm,"stdout",((PetscObject)snes)->tablevel,&vi->lsmonitor);CHKERRQ(ierr); 1970 } else if (!flg && vi->lsmonitor) { 1971 ierr = PetscViewerASCIIMonitorDestroy(&vi->lsmonitor);CHKERRQ(ierr); 1972 } 1973 PetscFunctionReturn(0); 1974 } 1975 EXTERN_C_END 1976 1977 /* 1978 SNESView_VI - Prints info from the SNESVI data structure. 1979 1980 Input Parameters: 1981 . SNES - the SNES context 1982 . viewer - visualization context 1983 1984 Application Interface Routine: SNESView() 1985 */ 1986 #undef __FUNCT__ 1987 #define __FUNCT__ "SNESView_VI" 1988 static PetscErrorCode SNESView_VI(SNES snes,PetscViewer viewer) 1989 { 1990 SNES_VI *vi = (SNES_VI *)snes->data; 1991 const char *cstr,*tstr; 1992 PetscErrorCode ierr; 1993 PetscBool iascii; 1994 1995 PetscFunctionBegin; 1996 ierr = PetscTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr); 1997 if (iascii) { 1998 if (vi->LineSearch == SNESLineSearchNo_VI) cstr = "SNESLineSearchNo"; 1999 else if (vi->LineSearch == SNESLineSearchQuadratic_VI) cstr = "SNESLineSearchQuadratic"; 2000 else if (vi->LineSearch == SNESLineSearchCubic_VI) cstr = "SNESLineSearchCubic"; 2001 else cstr = "unknown"; 2002 if (snes->ops->solve == SNESSolveVI_SS) tstr = "Semismooth"; 2003 else if (snes->ops->solve == SNESSolveVI_RS) tstr = "Reduced Space"; 2004 else if (snes->ops->solve == SNESSolveVI_RS2) tstr = "Augmented Space"; 2005 else tstr = "unknown"; 2006 ierr = PetscViewerASCIIPrintf(viewer," VI algorithm: %s\n",tstr);CHKERRQ(ierr); 2007 ierr = PetscViewerASCIIPrintf(viewer," line search variant: %s\n",cstr);CHKERRQ(ierr); 2008 ierr = PetscViewerASCIIPrintf(viewer," alpha=%G, maxstep=%G, minlambda=%G\n",vi->alpha,vi->maxstep,vi->minlambda);CHKERRQ(ierr); 2009 } else { 2010 SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Viewer type %s not supported for SNES EQ VI",((PetscObject)viewer)->type_name); 2011 } 2012 PetscFunctionReturn(0); 2013 } 2014 2015 #undef __FUNCT__ 2016 #define __FUNCT__ "SNESVISetVariableBounds" 2017 /*@ 2018 SNESVISetVariableBounds - Sets the lower and upper bounds for the solution vector. xl <= x <= xu. 2019 2020 Input Parameters: 2021 . snes - the SNES context. 2022 . xl - lower bound. 2023 . xu - upper bound. 2024 2025 Notes: 2026 If this routine is not called then the lower and upper bounds are set to 2027 PETSC_VI_INF and PETSC_VI_NINF respectively during SNESSetUp(). 2028 2029 @*/ 2030 PetscErrorCode SNESVISetVariableBounds(SNES snes, Vec xl, Vec xu) 2031 { 2032 SNES_VI *vi = (SNES_VI*)snes->data; 2033 2034 PetscFunctionBegin; 2035 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 2036 PetscValidHeaderSpecific(xl,VEC_CLASSID,2); 2037 PetscValidHeaderSpecific(xu,VEC_CLASSID,3); 2038 if (!snes->vec_func) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call SNESSetFunction() first"); 2039 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); 2040 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); 2041 2042 vi->usersetxbounds = PETSC_TRUE; 2043 vi->xl = xl; 2044 vi->xu = xu; 2045 PetscFunctionReturn(0); 2046 } 2047 2048 /* -------------------------------------------------------------------------- */ 2049 /* 2050 SNESSetFromOptions_VI - Sets various parameters for the SNESVI method. 2051 2052 Input Parameter: 2053 . snes - the SNES context 2054 2055 Application Interface Routine: SNESSetFromOptions() 2056 */ 2057 #undef __FUNCT__ 2058 #define __FUNCT__ "SNESSetFromOptions_VI" 2059 static PetscErrorCode SNESSetFromOptions_VI(SNES snes) 2060 { 2061 SNES_VI *vi = (SNES_VI *)snes->data; 2062 const char *lses[] = {"basic","basicnonorms","quadratic","cubic"}; 2063 const char *vies[] = {"ss","rs","rs2"}; 2064 PetscErrorCode ierr; 2065 PetscInt indx; 2066 PetscBool flg,set,flg2; 2067 2068 PetscFunctionBegin; 2069 ierr = PetscOptionsHead("SNES semismooth method options");CHKERRQ(ierr); 2070 ierr = PetscOptionsBool("-snes_vi_monitor","Monitor all non-active variables","None",PETSC_FALSE,&flg,0);CHKERRQ(ierr); 2071 if (flg) { 2072 ierr = SNESMonitorSet(snes,SNESMonitorVI,0,0);CHKERRQ(ierr); 2073 } 2074 ierr = PetscOptionsReal("-snes_ls_alpha","Function norm must decrease by","None",vi->alpha,&vi->alpha,0);CHKERRQ(ierr); 2075 ierr = PetscOptionsReal("-snes_ls_maxstep","Step must be less than","None",vi->maxstep,&vi->maxstep,0);CHKERRQ(ierr); 2076 ierr = PetscOptionsReal("-snes_ls_minlambda","Minimum lambda allowed","None",vi->minlambda,&vi->minlambda,0);CHKERRQ(ierr); 2077 ierr = PetscOptionsReal("-snes_vi_const_tol","constraint tolerance","None",vi->const_tol,&vi->const_tol,0);CHKERRQ(ierr); 2078 ierr = PetscOptionsBool("-snes_ls_monitor","Print progress of line searches","SNESLineSearchSetMonitor",vi->lsmonitor ? PETSC_TRUE : PETSC_FALSE,&flg,&set);CHKERRQ(ierr); 2079 if (set) {ierr = SNESLineSearchSetMonitor(snes,flg);CHKERRQ(ierr);} 2080 ierr = PetscOptionsEList("-snes_vi_type","Semismooth algorithm used","",vies,3,"ss",&indx,&flg2);CHKERRQ(ierr); 2081 if (flg2) { 2082 switch (indx) { 2083 case 0: 2084 snes->ops->solve = SNESSolveVI_SS; 2085 break; 2086 case 1: 2087 snes->ops->solve = SNESSolveVI_RS; 2088 break; 2089 case 2: 2090 snes->ops->solve = SNESSolveVI_RS2; 2091 } 2092 } 2093 ierr = PetscOptionsEList("-snes_ls","Line search used","SNESLineSearchSet",lses,4,"basic",&indx,&flg);CHKERRQ(ierr); 2094 if (flg) { 2095 switch (indx) { 2096 case 0: 2097 ierr = SNESLineSearchSet(snes,SNESLineSearchNo_VI,PETSC_NULL);CHKERRQ(ierr); 2098 break; 2099 case 1: 2100 ierr = SNESLineSearchSet(snes,SNESLineSearchNoNorms_VI,PETSC_NULL);CHKERRQ(ierr); 2101 break; 2102 case 2: 2103 ierr = SNESLineSearchSet(snes,SNESLineSearchQuadratic_VI,PETSC_NULL);CHKERRQ(ierr); 2104 break; 2105 case 3: 2106 ierr = SNESLineSearchSet(snes,SNESLineSearchCubic_VI,PETSC_NULL);CHKERRQ(ierr); 2107 break; 2108 } 2109 } 2110 ierr = PetscOptionsTail();CHKERRQ(ierr); 2111 PetscFunctionReturn(0); 2112 } 2113 /* -------------------------------------------------------------------------- */ 2114 /*MC 2115 SNESVI - Semismooth newton method based nonlinear solver that uses a line search 2116 2117 Options Database: 2118 + -snes_ls [cubic,quadratic,basic,basicnonorms] - Selects line search 2119 . -snes_ls_alpha <alpha> - Sets alpha 2120 . -snes_ls_maxstep <maxstep> - Sets the maximum stepsize the line search will use (if the 2-norm(y) > maxstep then scale y to be y = (maxstep/2-norm(y)) *y) 2121 . -snes_ls_minlambda <minlambda> - Sets the minimum lambda the line search will use minlambda / max_i ( y[i]/x[i] ) 2122 - -snes_ls_monitor - print information about progress of line searches 2123 2124 2125 Level: beginner 2126 2127 .seealso: SNESCreate(), SNES, SNESSetType(), SNESTR, SNESLineSearchSet(), 2128 SNESLineSearchSetPostCheck(), SNESLineSearchNo(), SNESLineSearchCubic(), SNESLineSearchQuadratic(), 2129 SNESLineSearchSet(), SNESLineSearchNoNorms(), SNESLineSearchSetPreCheck(), SNESLineSearchSetParams(), SNESLineSearchGetParams() 2130 2131 M*/ 2132 EXTERN_C_BEGIN 2133 #undef __FUNCT__ 2134 #define __FUNCT__ "SNESCreate_VI" 2135 PetscErrorCode SNESCreate_VI(SNES snes) 2136 { 2137 PetscErrorCode ierr; 2138 SNES_VI *vi; 2139 2140 PetscFunctionBegin; 2141 snes->ops->setup = SNESSetUp_VI; 2142 snes->ops->solve = SNESSolveVI_SS; 2143 snes->ops->destroy = SNESDestroy_VI; 2144 snes->ops->setfromoptions = SNESSetFromOptions_VI; 2145 snes->ops->view = SNESView_VI; 2146 snes->ops->reset = 0; /* XXX Implement!!! */ 2147 snes->ops->converged = SNESDefaultConverged_VI; 2148 2149 ierr = PetscNewLog(snes,SNES_VI,&vi);CHKERRQ(ierr); 2150 snes->data = (void*)vi; 2151 vi->alpha = 1.e-4; 2152 vi->maxstep = 1.e8; 2153 vi->minlambda = 1.e-12; 2154 vi->LineSearch = SNESLineSearchNo_VI; 2155 vi->lsP = PETSC_NULL; 2156 vi->postcheckstep = PETSC_NULL; 2157 vi->postcheck = PETSC_NULL; 2158 vi->precheckstep = PETSC_NULL; 2159 vi->precheck = PETSC_NULL; 2160 vi->const_tol = 2.2204460492503131e-16; 2161 vi->checkredundancy = PETSC_NULL; 2162 2163 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSetMonitor_C","SNESLineSearchSetMonitor_VI",SNESLineSearchSetMonitor_VI);CHKERRQ(ierr); 2164 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSet_C","SNESLineSearchSet_VI",SNESLineSearchSet_VI);CHKERRQ(ierr); 2165 2166 PetscFunctionReturn(0); 2167 } 2168 EXTERN_C_END 2169