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 SNESMonitor(snes,0,vi->phinorm); 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 SNESMonitor(snes,snes->iter,snes->norm); 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 SNESMonitor(snes,0,fnorm); 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 SNESMonitor(snes,snes->iter,snes->norm); 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 1035 PetscFunctionBegin; 1036 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 1037 PetscValidHeaderSpecific(is_act,IS_CLASSID,2); 1038 PetscValidPointer(is_redact,3); 1039 PetscCheckSameComm(snes,1,is_act,2); 1040 1041 /* Create IS for reduced active set, its size and indices will be set by the Matlab function */ 1042 ierr = ISCreate(((PetscObject)snes)->comm,is_redact);CHKERRQ(ierr); 1043 /* call Matlab function in ctx */ 1044 ierr = PetscMemcpy(&ls,&snes,sizeof(snes));CHKERRQ(ierr); 1045 ierr = PetscMemcpy(&l1,&is_act,sizeof(is_act));CHKERRQ(ierr); 1046 ierr = PetscMemcpy(&l2,is_redact,sizeof(is_act));CHKERRQ(ierr); 1047 prhs[0] = mxCreateDoubleScalar((double)ls); 1048 prhs[1] = mxCreateDoubleScalar((double)l1); 1049 prhs[2] = mxCreateDoubleScalar((double)l2); 1050 prhs[3] = mxCreateString(sctx->funcname); 1051 prhs[4] = sctx->ctx; 1052 ierr = mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESVIRedundancyCheckInternal");CHKERRQ(ierr); 1053 ierr = mxGetScalar(plhs[0]);CHKERRQ(ierr); 1054 PetscInt n; 1055 ierr = ISGetSize(*is_redact,&n);CHKERRQ(ierr); 1056 PetscPrintf(PETSC_COMM_SELF,"IS_size = %d\n",n); 1057 mxDestroyArray(prhs[0]); 1058 mxDestroyArray(prhs[1]); 1059 mxDestroyArray(prhs[2]); 1060 mxDestroyArray(prhs[3]); 1061 mxDestroyArray(prhs[4]); 1062 mxDestroyArray(plhs[0]); 1063 PetscFunctionReturn(0); 1064 } 1065 1066 #undef __FUNCT__ 1067 #define __FUNCT__ "SNESVISetRedundancyCheckMatlab" 1068 PetscErrorCode SNESVISetRedundancyCheckMatlab(SNES snes,const char* func,mxArray* ctx) 1069 { 1070 PetscErrorCode ierr; 1071 SNESMatlabContext *sctx; 1072 1073 PetscFunctionBegin; 1074 /* currently sctx is memory bleed */ 1075 ierr = PetscMalloc(sizeof(SNESMatlabContext),&sctx);CHKERRQ(ierr); 1076 ierr = PetscStrallocpy(func,&sctx->funcname);CHKERRQ(ierr); 1077 sctx->ctx = mxDuplicateArray(ctx); 1078 ierr = SNESVISetRedundancyCheck(snes,SNESVIRedundancyCheck_Matlab,sctx);CHKERRQ(ierr); 1079 PetscFunctionReturn(0); 1080 } 1081 1082 #endif 1083 1084 1085 /* Variational Inequality solver using augmented space method. It does the opposite of the 1086 reduced space method i.e. it identifies the active set variables and instead of discarding 1087 them it augments the original system by introducing additional equality 1088 constraint equations for active set variables. The user can optionally provide an IS for 1089 a subset of 'redundant' active set variables which will treated as free variables. 1090 Specific implementation for Allen-Cahn problem 1091 */ 1092 #undef __FUNCT__ 1093 #define __FUNCT__ "SNESSolveVI_RS2" 1094 PetscErrorCode SNESSolveVI_RS2(SNES snes) 1095 { 1096 SNES_VI *vi = (SNES_VI*)snes->data; 1097 PetscErrorCode ierr; 1098 PetscInt maxits,i,lits; 1099 PetscBool lssucceed; 1100 MatStructure flg = DIFFERENT_NONZERO_PATTERN; 1101 PetscReal fnorm,gnorm,xnorm=0,ynorm; 1102 Vec Y,X,F,G,W; 1103 KSPConvergedReason kspreason; 1104 1105 PetscFunctionBegin; 1106 snes->numFailures = 0; 1107 snes->numLinearSolveFailures = 0; 1108 snes->reason = SNES_CONVERGED_ITERATING; 1109 1110 maxits = snes->max_its; /* maximum number of iterations */ 1111 X = snes->vec_sol; /* solution vector */ 1112 F = snes->vec_func; /* residual vector */ 1113 Y = snes->work[0]; /* work vectors */ 1114 G = snes->work[1]; 1115 W = snes->work[2]; 1116 1117 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1118 snes->iter = 0; 1119 snes->norm = 0.0; 1120 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1121 1122 ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr); 1123 ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr); 1124 if (snes->domainerror) { 1125 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 1126 PetscFunctionReturn(0); 1127 } 1128 ierr = SNESVIComputeInactiveSetFnorm(snes,F,X,&fnorm);CHKERRQ(ierr); 1129 ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr); /* xnorm <- ||x|| */ 1130 ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr); 1131 if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1132 1133 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1134 snes->norm = fnorm; 1135 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1136 SNESLogConvHistory(snes,fnorm,0); 1137 SNESMonitor(snes,0,fnorm); 1138 1139 /* set parameter for default relative tolerance convergence test */ 1140 snes->ttol = fnorm*snes->rtol; 1141 /* test convergence */ 1142 ierr = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1143 if (snes->reason) PetscFunctionReturn(0); 1144 1145 for (i=0; i<maxits; i++) { 1146 IS IS_act,IS_inact; /* _act -> active set _inact -> inactive set */ 1147 IS IS_redact; /* redundant active set */ 1148 Mat J_aug,Jpre_aug; 1149 Vec F_aug,Y_aug; 1150 PetscInt nis_redact,nis_act; 1151 const PetscInt *idx_redact,*idx_act; 1152 PetscInt k; 1153 PetscInt *idx_actkept=PETSC_NULL,nkept; /* list of kept active set */ 1154 PetscScalar *f,*f2; 1155 PetscBool isequal; 1156 PetscInt i1=0,j1=0; 1157 1158 /* Call general purpose update function */ 1159 if (snes->ops->update) { 1160 ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr); 1161 } 1162 ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr); 1163 1164 /* Create active and inactive index sets */ 1165 ierr = SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&IS_inact);CHKERRQ(ierr); 1166 1167 /* Get local active set size */ 1168 ierr = ISGetLocalSize(IS_act,&nis_act);CHKERRQ(ierr); 1169 ierr = ISGetIndices(IS_act,&idx_act);CHKERRQ(ierr); 1170 if(nis_act) { 1171 if(vi->checkredundancy) { 1172 (*vi->checkredundancy)(snes,IS_act,&IS_redact,vi->ctxP); 1173 } 1174 1175 if(!IS_redact) { 1176 /* User called checkredundancy function but didn't create IS_redact because 1177 there were no redundant active set variables */ 1178 /* Copy over all active set indices to the list */ 1179 PetscPrintf(PETSC_COMM_SELF,"Came here 1\n"); 1180 ierr = PetscMalloc(nis_act*sizeof(PetscInt),&idx_actkept);CHKERRQ(ierr); 1181 for(k=0;k < nis_act;k++) idx_actkept[k] = idx_act[k]; 1182 nkept = nis_act; 1183 } else { 1184 PetscPrintf(PETSC_COMM_SELF,"Came here 2\n"); 1185 ierr = ISGetLocalSize(IS_redact,&nis_redact);CHKERRQ(ierr); 1186 ierr = PetscMalloc((nis_act-nis_redact)*sizeof(PetscInt),&idx_actkept);CHKERRQ(ierr); 1187 1188 /* Create reduced active set list */ 1189 ierr = ISGetIndices(IS_act,&idx_act);CHKERRQ(ierr); 1190 ierr = ISGetIndices(IS_redact,&idx_redact);CHKERRQ(ierr); 1191 j1 = 0;nkept = 0; 1192 for(k=0;k<nis_act;k++) { 1193 if(j1 < nis_redact && idx_act[k] == idx_redact[j1]) j1++; 1194 else idx_actkept[nkept++] = idx_act[k]; 1195 } 1196 ierr = ISRestoreIndices(IS_act,&idx_act);CHKERRQ(ierr); 1197 ierr = ISRestoreIndices(IS_redact,&idx_redact);CHKERRQ(ierr); 1198 1199 ierr = ISDestroy(&IS_redact);CHKERRQ(ierr); 1200 } 1201 1202 /* Create augmented F and Y */ 1203 ierr = VecCreate(((PetscObject)snes)->comm,&F_aug);CHKERRQ(ierr); 1204 ierr = VecSetSizes(F_aug,F->map->n+nkept,PETSC_DECIDE);CHKERRQ(ierr); 1205 ierr = VecSetFromOptions(F_aug);CHKERRQ(ierr); 1206 ierr = VecDuplicate(F_aug,&Y_aug);CHKERRQ(ierr); 1207 1208 /* Copy over F to F_aug in the first n locations */ 1209 ierr = VecGetArray(F,&f);CHKERRQ(ierr); 1210 ierr = VecGetArray(F_aug,&f2);CHKERRQ(ierr); 1211 ierr = PetscMemcpy(f2,f,F->map->n*sizeof(PetscScalar));CHKERRQ(ierr); 1212 ierr = VecRestoreArray(F,&f);CHKERRQ(ierr); 1213 ierr = VecRestoreArray(F_aug,&f2);CHKERRQ(ierr); 1214 1215 /* Create the augmented jacobian matrix */ 1216 ierr = MatCreate(((PetscObject)snes)->comm,&J_aug);CHKERRQ(ierr); 1217 ierr = MatSetSizes(J_aug,X->map->n+nkept,X->map->n+nkept,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr); 1218 ierr = MatSetFromOptions(J_aug);CHKERRQ(ierr); 1219 1220 1221 { /* local vars */ 1222 /* Preallocate augmented matrix and set values in it...Doing only sequential case first*/ 1223 PetscInt ncols; 1224 const PetscInt *cols; 1225 const PetscScalar *vals; 1226 PetscScalar value=1.0; 1227 PetscInt row,col; 1228 PetscInt *d_nnz; 1229 1230 ierr = PetscMalloc((X->map->n+nkept)*sizeof(PetscInt),&d_nnz);CHKERRQ(ierr); 1231 ierr = PetscMemzero(d_nnz,(X->map->n+nkept)*sizeof(PetscInt));CHKERRQ(ierr); 1232 for(row=0;row<snes->jacobian->rmap->n;row++) { 1233 ierr = MatGetRow(snes->jacobian,row,&ncols,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr); 1234 d_nnz[row] += ncols; 1235 ierr = MatRestoreRow(snes->jacobian,row,&ncols,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr); 1236 } 1237 1238 for(k=0;k<nkept;k++) { 1239 d_nnz[idx_actkept[k]] += 1; 1240 d_nnz[snes->jacobian->rmap->n+k] += 1; 1241 } 1242 ierr = MatSeqAIJSetPreallocation(J_aug,PETSC_NULL,d_nnz);CHKERRQ(ierr); 1243 1244 ierr = PetscFree(d_nnz);CHKERRQ(ierr); 1245 1246 /* Set the original jacobian matrix in J_aug */ 1247 for(row=0;row<snes->jacobian->rmap->n;row++) { 1248 ierr = MatGetRow(snes->jacobian,row,&ncols,&cols,&vals);CHKERRQ(ierr); 1249 ierr = MatSetValues(J_aug,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr); 1250 ierr = MatRestoreRow(snes->jacobian,row,&ncols,&cols,&vals);CHKERRQ(ierr); 1251 } 1252 /* Add the augmented part */ 1253 for(k=0;k<nkept;k++) { 1254 row = idx_actkept[k]; 1255 col = snes->jacobian->rmap->n+k; 1256 ierr = MatSetValues(J_aug,1,&row,1,&col,&value,INSERT_VALUES);CHKERRQ(ierr); 1257 ierr = MatSetValues(J_aug,1,&col,1,&row,&value,INSERT_VALUES);CHKERRQ(ierr); 1258 } 1259 ierr = MatAssemblyBegin(J_aug,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 1260 ierr = MatAssemblyEnd(J_aug,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 1261 /* Only considering prejac = jac for now */ 1262 Jpre_aug = J_aug; 1263 } /* local vars*/ 1264 } else { 1265 F_aug = F; J_aug = snes->jacobian; Y_aug = Y; Jpre_aug = snes->jacobian_pre; 1266 } 1267 1268 ierr = ISEqual(vi->IS_inact_prev,IS_inact,&isequal);CHKERRQ(ierr); 1269 if (!isequal) { 1270 ierr = SNESVIResetPCandKSP(snes,J_aug,Jpre_aug);CHKERRQ(ierr); 1271 } 1272 ierr = KSPSetOperators(snes->ksp,J_aug,Jpre_aug,flg);CHKERRQ(ierr); 1273 ierr = KSPSetUp(snes->ksp);CHKERRQ(ierr); 1274 /* { 1275 PC pc; 1276 PetscBool flg; 1277 ierr = KSPGetPC(snes->ksp,&pc);CHKERRQ(ierr); 1278 ierr = PetscTypeCompare((PetscObject)pc,PCFIELDSPLIT,&flg);CHKERRQ(ierr); 1279 if (flg) { 1280 KSP *subksps; 1281 ierr = PCFieldSplitGetSubKSP(pc,PETSC_NULL,&subksps);CHKERRQ(ierr); 1282 ierr = KSPGetPC(subksps[0],&pc);CHKERRQ(ierr); 1283 ierr = PetscFree(subksps);CHKERRQ(ierr); 1284 ierr = PetscTypeCompare((PetscObject)pc,PCBJACOBI,&flg);CHKERRQ(ierr); 1285 if (flg) { 1286 PetscInt n,N = 101*101,j,cnts[3] = {0,0,0}; 1287 const PetscInt *ii; 1288 1289 ierr = ISGetSize(IS_inact,&n);CHKERRQ(ierr); 1290 ierr = ISGetIndices(IS_inact,&ii);CHKERRQ(ierr); 1291 for (j=0; j<n; j++) { 1292 if (ii[j] < N) cnts[0]++; 1293 else if (ii[j] < 2*N) cnts[1]++; 1294 else if (ii[j] < 3*N) cnts[2]++; 1295 } 1296 ierr = ISRestoreIndices(IS_inact,&ii);CHKERRQ(ierr); 1297 1298 ierr = PCBJacobiSetTotalBlocks(pc,3,cnts);CHKERRQ(ierr); 1299 } 1300 } 1301 } 1302 */ 1303 ierr = SNES_KSPSolve(snes,snes->ksp,F_aug,Y_aug);CHKERRQ(ierr); 1304 ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr); 1305 if (kspreason < 0) { 1306 if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) { 1307 ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr); 1308 snes->reason = SNES_DIVERGED_LINEAR_SOLVE; 1309 break; 1310 } 1311 } 1312 1313 if(nis_act) { 1314 PetscScalar *y1,*y2; 1315 ierr = VecGetArray(Y,&y1);CHKERRQ(ierr); 1316 ierr = VecGetArray(Y_aug,&y2);CHKERRQ(ierr); 1317 /* Copy over inactive Y_aug to Y */ 1318 j1 = 0; 1319 for(i1=Y->map->rstart;i1 < Y->map->rend;i1++) { 1320 if(j1 < nkept && idx_actkept[j1] == i1) j1++; 1321 else y1[i1-Y->map->rstart] = y2[i1-Y->map->rstart]; 1322 } 1323 ierr = VecRestoreArray(Y,&y1);CHKERRQ(ierr); 1324 ierr = VecRestoreArray(Y_aug,&y2);CHKERRQ(ierr); 1325 1326 ierr = VecDestroy(&F_aug);CHKERRQ(ierr); 1327 ierr = VecDestroy(&Y_aug);CHKERRQ(ierr); 1328 ierr = MatDestroy(&J_aug);CHKERRQ(ierr); 1329 ierr = PetscFree(idx_actkept);CHKERRQ(ierr); 1330 } 1331 1332 if (!isequal) { 1333 ierr = ISDestroy(&vi->IS_inact_prev);CHKERRQ(ierr); 1334 ierr = ISDuplicate(IS_inact,&vi->IS_inact_prev);CHKERRQ(ierr); 1335 } 1336 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 1337 1338 ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr); 1339 snes->linear_its += lits; 1340 ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr); 1341 /* 1342 if (vi->precheckstep) { 1343 PetscBool changed_y = PETSC_FALSE; 1344 ierr = (*vi->precheckstep)(snes,X,Y,vi->precheck,&changed_y);CHKERRQ(ierr); 1345 } 1346 1347 if (PetscLogPrintInfo){ 1348 ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr); 1349 } 1350 */ 1351 /* Compute a (scaled) negative update in the line search routine: 1352 Y <- X - lambda*Y 1353 and evaluate G = function(Y) (depends on the line search). 1354 */ 1355 ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr); 1356 ynorm = 1; gnorm = fnorm; 1357 ierr = (*vi->LineSearch)(snes,vi->lsP,X,F,G,Y,W,fnorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr); 1358 ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",fnorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr); 1359 if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break; 1360 if (snes->domainerror) { 1361 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 1362 PetscFunctionReturn(0); 1363 } 1364 if (!lssucceed) { 1365 if (++snes->numFailures >= snes->maxFailures) { 1366 PetscBool ismin; 1367 snes->reason = SNES_DIVERGED_LINE_SEARCH; 1368 ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr); 1369 if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN; 1370 break; 1371 } 1372 } 1373 /* Update function and solution vectors */ 1374 fnorm = gnorm; 1375 ierr = VecCopy(G,F);CHKERRQ(ierr); 1376 ierr = VecCopy(W,X);CHKERRQ(ierr); 1377 /* Monitor convergence */ 1378 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1379 snes->iter = i+1; 1380 snes->norm = fnorm; 1381 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1382 SNESLogConvHistory(snes,snes->norm,lits); 1383 SNESMonitor(snes,snes->iter,snes->norm); 1384 /* Test for convergence, xnorm = || X || */ 1385 if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); } 1386 ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1387 if (snes->reason) break; 1388 } 1389 if (i == maxits) { 1390 ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr); 1391 if(!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT; 1392 } 1393 PetscFunctionReturn(0); 1394 } 1395 1396 /* -------------------------------------------------------------------------- */ 1397 /* 1398 SNESSetUp_VI - Sets up the internal data structures for the later use 1399 of the SNESVI nonlinear solver. 1400 1401 Input Parameter: 1402 . snes - the SNES context 1403 . x - the solution vector 1404 1405 Application Interface Routine: SNESSetUp() 1406 1407 Notes: 1408 For basic use of the SNES solvers, the user need not explicitly call 1409 SNESSetUp(), since these actions will automatically occur during 1410 the call to SNESSolve(). 1411 */ 1412 #undef __FUNCT__ 1413 #define __FUNCT__ "SNESSetUp_VI" 1414 PetscErrorCode SNESSetUp_VI(SNES snes) 1415 { 1416 PetscErrorCode ierr; 1417 SNES_VI *vi = (SNES_VI*) snes->data; 1418 PetscInt i_start[3],i_end[3]; 1419 1420 PetscFunctionBegin; 1421 1422 ierr = SNESDefaultGetWork(snes,3);CHKERRQ(ierr); 1423 1424 /* If the lower and upper bound on variables are not set, set it to 1425 -Inf and Inf */ 1426 if (!vi->xl && !vi->xu) { 1427 vi->usersetxbounds = PETSC_FALSE; 1428 ierr = VecDuplicate(snes->vec_sol, &vi->xl); CHKERRQ(ierr); 1429 ierr = VecSet(vi->xl,PETSC_VI_NINF);CHKERRQ(ierr); 1430 ierr = VecDuplicate(snes->vec_sol, &vi->xu); CHKERRQ(ierr); 1431 ierr = VecSet(vi->xu,PETSC_VI_INF);CHKERRQ(ierr); 1432 } else { 1433 /* Check if lower bound, upper bound and solution vector distribution across the processors is identical */ 1434 ierr = VecGetOwnershipRange(snes->vec_sol,i_start,i_end);CHKERRQ(ierr); 1435 ierr = VecGetOwnershipRange(vi->xl,i_start+1,i_end+1);CHKERRQ(ierr); 1436 ierr = VecGetOwnershipRange(vi->xu,i_start+2,i_end+2);CHKERRQ(ierr); 1437 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])) 1438 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."); 1439 } 1440 if (snes->ops->solve != SNESSolveVI_SS) { 1441 /* Set up previous active index set for the first snes solve 1442 vi->IS_inact_prev = 0,1,2,....N */ 1443 PetscInt *indices; 1444 PetscInt i,n,rstart,rend; 1445 1446 ierr = VecGetOwnershipRange(snes->vec_sol,&rstart,&rend);CHKERRQ(ierr); 1447 ierr = VecGetLocalSize(snes->vec_sol,&n);CHKERRQ(ierr); 1448 ierr = PetscMalloc(n*sizeof(PetscInt),&indices);CHKERRQ(ierr); 1449 for(i=0;i < n; i++) indices[i] = rstart + i; 1450 ierr = ISCreateGeneral(((PetscObject)snes)->comm,n,indices,PETSC_OWN_POINTER,&vi->IS_inact_prev); 1451 } 1452 1453 if (snes->ops->solve == SNESSolveVI_SS) { 1454 ierr = VecDuplicate(snes->vec_sol, &vi->dpsi);CHKERRQ(ierr); 1455 ierr = VecDuplicate(snes->vec_sol, &vi->phi); CHKERRQ(ierr); 1456 ierr = VecDuplicate(snes->vec_sol, &vi->Da); CHKERRQ(ierr); 1457 ierr = VecDuplicate(snes->vec_sol, &vi->Db); CHKERRQ(ierr); 1458 ierr = VecDuplicate(snes->vec_sol, &vi->z);CHKERRQ(ierr); 1459 ierr = VecDuplicate(snes->vec_sol, &vi->t); CHKERRQ(ierr); 1460 } 1461 PetscFunctionReturn(0); 1462 } 1463 /* -------------------------------------------------------------------------- */ 1464 /* 1465 SNESDestroy_VI - Destroys the private SNES_VI context that was created 1466 with SNESCreate_VI(). 1467 1468 Input Parameter: 1469 . snes - the SNES context 1470 1471 Application Interface Routine: SNESDestroy() 1472 */ 1473 #undef __FUNCT__ 1474 #define __FUNCT__ "SNESDestroy_VI" 1475 PetscErrorCode SNESDestroy_VI(SNES snes) 1476 { 1477 SNES_VI *vi = (SNES_VI*) snes->data; 1478 PetscErrorCode ierr; 1479 1480 PetscFunctionBegin; 1481 if (snes->ops->solve != SNESSolveVI_SS) { 1482 ierr = ISDestroy(&vi->IS_inact_prev); 1483 } 1484 1485 if (snes->ops->solve == SNESSolveVI_SS) { 1486 /* clear vectors */ 1487 ierr = VecDestroy(&vi->dpsi);CHKERRQ(ierr); 1488 ierr = VecDestroy(&vi->phi); CHKERRQ(ierr); 1489 ierr = VecDestroy(&vi->Da); CHKERRQ(ierr); 1490 ierr = VecDestroy(&vi->Db); CHKERRQ(ierr); 1491 ierr = VecDestroy(&vi->z); CHKERRQ(ierr); 1492 ierr = VecDestroy(&vi->t); CHKERRQ(ierr); 1493 } 1494 1495 if (!vi->usersetxbounds) { 1496 ierr = VecDestroy(&vi->xl); CHKERRQ(ierr); 1497 ierr = VecDestroy(&vi->xu); CHKERRQ(ierr); 1498 } 1499 1500 ierr = PetscViewerASCIIMonitorDestroy(&vi->lsmonitor);CHKERRQ(ierr); 1501 ierr = PetscFree(snes->data);CHKERRQ(ierr); 1502 1503 /* clear composed functions */ 1504 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSet_C","",PETSC_NULL);CHKERRQ(ierr); 1505 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSetMonitor_C","",PETSC_NULL);CHKERRQ(ierr); 1506 PetscFunctionReturn(0); 1507 } 1508 1509 /* -------------------------------------------------------------------------- */ 1510 #undef __FUNCT__ 1511 #define __FUNCT__ "SNESLineSearchNo_VI" 1512 1513 /* 1514 This routine does not actually do a line search but it takes a full newton 1515 step while ensuring that the new iterates remain within the constraints. 1516 1517 */ 1518 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) 1519 { 1520 PetscErrorCode ierr; 1521 SNES_VI *vi = (SNES_VI*)snes->data; 1522 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1523 1524 PetscFunctionBegin; 1525 *flag = PETSC_TRUE; 1526 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1527 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); /* ynorm = || y || */ 1528 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1529 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1530 if (vi->postcheckstep) { 1531 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1532 } 1533 if (changed_y) { 1534 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1535 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1536 } 1537 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1538 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1539 if (!snes->domainerror) { 1540 if (snes->ops->solve != SNESSolveVI_SS) { 1541 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1542 } else { 1543 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); /* gnorm = || g || */ 1544 } 1545 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1546 } 1547 if (vi->lsmonitor) { 1548 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1549 } 1550 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1551 PetscFunctionReturn(0); 1552 } 1553 1554 /* -------------------------------------------------------------------------- */ 1555 #undef __FUNCT__ 1556 #define __FUNCT__ "SNESLineSearchNoNorms_VI" 1557 1558 /* 1559 This routine is a copy of SNESLineSearchNoNorms in snes/impls/ls/ls.c 1560 */ 1561 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) 1562 { 1563 PetscErrorCode ierr; 1564 SNES_VI *vi = (SNES_VI*)snes->data; 1565 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1566 1567 PetscFunctionBegin; 1568 *flag = PETSC_TRUE; 1569 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1570 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1571 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1572 if (vi->postcheckstep) { 1573 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1574 } 1575 if (changed_y) { 1576 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1577 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1578 } 1579 1580 /* don't evaluate function the last time through */ 1581 if (snes->iter < snes->max_its-1) { 1582 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1583 } 1584 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1585 PetscFunctionReturn(0); 1586 } 1587 1588 /* -------------------------------------------------------------------------- */ 1589 #undef __FUNCT__ 1590 #define __FUNCT__ "SNESLineSearchCubic_VI" 1591 /* 1592 This routine implements a cubic line search while doing a projection on the variable bounds 1593 */ 1594 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) 1595 { 1596 PetscReal initslope,lambdaprev,gnormprev,a,b,d,t1,t2,rellength; 1597 PetscReal minlambda,lambda,lambdatemp; 1598 #if defined(PETSC_USE_COMPLEX) 1599 PetscScalar cinitslope; 1600 #endif 1601 PetscErrorCode ierr; 1602 PetscInt count; 1603 SNES_VI *vi = (SNES_VI*)snes->data; 1604 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1605 MPI_Comm comm; 1606 1607 PetscFunctionBegin; 1608 ierr = PetscObjectGetComm((PetscObject)snes,&comm);CHKERRQ(ierr); 1609 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1610 *flag = PETSC_TRUE; 1611 1612 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); 1613 if (*ynorm == 0.0) { 1614 if (vi->lsmonitor) { 1615 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Initial direction and size is 0\n");CHKERRQ(ierr); 1616 } 1617 *gnorm = fnorm; 1618 ierr = VecCopy(x,w);CHKERRQ(ierr); 1619 ierr = VecCopy(f,g);CHKERRQ(ierr); 1620 *flag = PETSC_FALSE; 1621 goto theend1; 1622 } 1623 if (*ynorm > vi->maxstep) { /* Step too big, so scale back */ 1624 if (vi->lsmonitor) { 1625 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Scaling step by %G old ynorm %G\n",vi->maxstep/(*ynorm),*ynorm);CHKERRQ(ierr); 1626 } 1627 ierr = VecScale(y,vi->maxstep/(*ynorm));CHKERRQ(ierr); 1628 *ynorm = vi->maxstep; 1629 } 1630 ierr = VecMaxPointwiseDivide(y,x,&rellength);CHKERRQ(ierr); 1631 minlambda = vi->minlambda/rellength; 1632 ierr = MatMult(snes->jacobian,y,w);CHKERRQ(ierr); 1633 #if defined(PETSC_USE_COMPLEX) 1634 ierr = VecDot(f,w,&cinitslope);CHKERRQ(ierr); 1635 initslope = PetscRealPart(cinitslope); 1636 #else 1637 ierr = VecDot(f,w,&initslope);CHKERRQ(ierr); 1638 #endif 1639 if (initslope > 0.0) initslope = -initslope; 1640 if (initslope == 0.0) initslope = -1.0; 1641 1642 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1643 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1644 if (snes->nfuncs >= snes->max_funcs) { 1645 ierr = PetscInfo(snes,"Exceeded maximum function evaluations, while checking full step length!\n");CHKERRQ(ierr); 1646 *flag = PETSC_FALSE; 1647 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1648 goto theend1; 1649 } 1650 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1651 if (snes->ops->solve != SNESSolveVI_SS) { 1652 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1653 } else { 1654 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1655 } 1656 if (snes->domainerror) { 1657 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1658 PetscFunctionReturn(0); 1659 } 1660 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1661 ierr = PetscInfo2(snes,"Initial fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1662 if (.5*(*gnorm)*(*gnorm) <= .5*fnorm*fnorm + vi->alpha*initslope) { /* Sufficient reduction */ 1663 if (vi->lsmonitor) { 1664 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1665 } 1666 goto theend1; 1667 } 1668 1669 /* Fit points with quadratic */ 1670 lambda = 1.0; 1671 lambdatemp = -initslope/((*gnorm)*(*gnorm) - fnorm*fnorm - 2.0*initslope); 1672 lambdaprev = lambda; 1673 gnormprev = *gnorm; 1674 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 1675 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 1676 else lambda = lambdatemp; 1677 1678 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 1679 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1680 if (snes->nfuncs >= snes->max_funcs) { 1681 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while attempting quadratic backtracking! %D \n",snes->nfuncs);CHKERRQ(ierr); 1682 *flag = PETSC_FALSE; 1683 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1684 goto theend1; 1685 } 1686 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1687 if (snes->ops->solve != SNESSolveVI_SS) { 1688 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1689 } else { 1690 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1691 } 1692 if (snes->domainerror) { 1693 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1694 PetscFunctionReturn(0); 1695 } 1696 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1697 if (vi->lsmonitor) { 1698 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: gnorm after quadratic fit %G\n",*gnorm);CHKERRQ(ierr); 1699 } 1700 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* sufficient reduction */ 1701 if (vi->lsmonitor) { 1702 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Quadratically determined step, lambda=%18.16e\n",lambda);CHKERRQ(ierr); 1703 } 1704 goto theend1; 1705 } 1706 1707 /* Fit points with cubic */ 1708 count = 1; 1709 while (PETSC_TRUE) { 1710 if (lambda <= minlambda) { 1711 if (vi->lsmonitor) { 1712 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: unable to find good step length! After %D tries \n",count);CHKERRQ(ierr); 1713 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); 1714 } 1715 *flag = PETSC_FALSE; 1716 break; 1717 } 1718 t1 = .5*((*gnorm)*(*gnorm) - fnorm*fnorm) - lambda*initslope; 1719 t2 = .5*(gnormprev*gnormprev - fnorm*fnorm) - lambdaprev*initslope; 1720 a = (t1/(lambda*lambda) - t2/(lambdaprev*lambdaprev))/(lambda-lambdaprev); 1721 b = (-lambdaprev*t1/(lambda*lambda) + lambda*t2/(lambdaprev*lambdaprev))/(lambda-lambdaprev); 1722 d = b*b - 3*a*initslope; 1723 if (d < 0.0) d = 0.0; 1724 if (a == 0.0) { 1725 lambdatemp = -initslope/(2.0*b); 1726 } else { 1727 lambdatemp = (-b + sqrt(d))/(3.0*a); 1728 } 1729 lambdaprev = lambda; 1730 gnormprev = *gnorm; 1731 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 1732 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 1733 else lambda = lambdatemp; 1734 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 1735 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1736 if (snes->nfuncs >= snes->max_funcs) { 1737 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while looking for good step length! %D \n",count);CHKERRQ(ierr); 1738 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); 1739 *flag = PETSC_FALSE; 1740 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1741 break; 1742 } 1743 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1744 if (snes->ops->solve != SNESSolveVI_SS) { 1745 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1746 } else { 1747 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1748 } 1749 if (snes->domainerror) { 1750 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1751 PetscFunctionReturn(0); 1752 } 1753 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1754 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* is reduction enough? */ 1755 if (vi->lsmonitor) { 1756 ierr = PetscPrintf(comm," Line search: Cubically determined step, current gnorm %G lambda=%18.16e\n",*gnorm,lambda);CHKERRQ(ierr); 1757 } 1758 break; 1759 } else { 1760 if (vi->lsmonitor) { 1761 ierr = PetscPrintf(comm," Line search: Cubic step no good, shrinking lambda, current gnorm %G lambda=%18.16e\n",*gnorm,lambda);CHKERRQ(ierr); 1762 } 1763 } 1764 count++; 1765 } 1766 theend1: 1767 /* Optional user-defined check for line search step validity */ 1768 if (vi->postcheckstep && *flag) { 1769 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1770 if (changed_y) { 1771 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1772 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1773 } 1774 if (changed_y || changed_w) { /* recompute the function if the step has changed */ 1775 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1776 if (snes->ops->solve != SNESSolveVI_SS) { 1777 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1778 } else { 1779 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1780 } 1781 if (snes->domainerror) { 1782 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1783 PetscFunctionReturn(0); 1784 } 1785 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1786 ierr = VecNormBegin(y,NORM_2,ynorm);CHKERRQ(ierr); 1787 ierr = VecNormEnd(y,NORM_2,ynorm);CHKERRQ(ierr); 1788 } 1789 } 1790 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1791 PetscFunctionReturn(0); 1792 } 1793 1794 #undef __FUNCT__ 1795 #define __FUNCT__ "SNESLineSearchQuadratic_VI" 1796 /* 1797 This routine does a quadratic line search while keeping the iterates within the variable bounds 1798 */ 1799 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) 1800 { 1801 /* 1802 Note that for line search purposes we work with with the related 1803 minimization problem: 1804 min z(x): R^n -> R, 1805 where z(x) = .5 * fnorm*fnorm,and fnorm = || f ||_2. 1806 */ 1807 PetscReal initslope,minlambda,lambda,lambdatemp,rellength; 1808 #if defined(PETSC_USE_COMPLEX) 1809 PetscScalar cinitslope; 1810 #endif 1811 PetscErrorCode ierr; 1812 PetscInt count; 1813 SNES_VI *vi = (SNES_VI*)snes->data; 1814 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1815 1816 PetscFunctionBegin; 1817 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1818 *flag = PETSC_TRUE; 1819 1820 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); 1821 if (*ynorm == 0.0) { 1822 if (vi->lsmonitor) { 1823 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor,"Line search: Direction and size is 0\n");CHKERRQ(ierr); 1824 } 1825 *gnorm = fnorm; 1826 ierr = VecCopy(x,w);CHKERRQ(ierr); 1827 ierr = VecCopy(f,g);CHKERRQ(ierr); 1828 *flag = PETSC_FALSE; 1829 goto theend2; 1830 } 1831 if (*ynorm > vi->maxstep) { /* Step too big, so scale back */ 1832 ierr = VecScale(y,vi->maxstep/(*ynorm));CHKERRQ(ierr); 1833 *ynorm = vi->maxstep; 1834 } 1835 ierr = VecMaxPointwiseDivide(y,x,&rellength);CHKERRQ(ierr); 1836 minlambda = vi->minlambda/rellength; 1837 ierr = MatMult(snes->jacobian,y,w);CHKERRQ(ierr); 1838 #if defined(PETSC_USE_COMPLEX) 1839 ierr = VecDot(f,w,&cinitslope);CHKERRQ(ierr); 1840 initslope = PetscRealPart(cinitslope); 1841 #else 1842 ierr = VecDot(f,w,&initslope);CHKERRQ(ierr); 1843 #endif 1844 if (initslope > 0.0) initslope = -initslope; 1845 if (initslope == 0.0) initslope = -1.0; 1846 ierr = PetscInfo1(snes,"Initslope %G \n",initslope);CHKERRQ(ierr); 1847 1848 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1849 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1850 if (snes->nfuncs >= snes->max_funcs) { 1851 ierr = PetscInfo(snes,"Exceeded maximum function evaluations, while checking full step length!\n");CHKERRQ(ierr); 1852 *flag = PETSC_FALSE; 1853 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1854 goto theend2; 1855 } 1856 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1857 if (snes->ops->solve != SNESSolveVI_SS) { 1858 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1859 } else { 1860 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1861 } 1862 if (snes->domainerror) { 1863 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1864 PetscFunctionReturn(0); 1865 } 1866 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1867 if (.5*(*gnorm)*(*gnorm) <= .5*fnorm*fnorm + vi->alpha*initslope) { /* Sufficient reduction */ 1868 if (vi->lsmonitor) { 1869 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1870 } 1871 goto theend2; 1872 } 1873 1874 /* Fit points with quadratic */ 1875 lambda = 1.0; 1876 count = 1; 1877 while (PETSC_TRUE) { 1878 if (lambda <= minlambda) { /* bad luck; use full step */ 1879 if (vi->lsmonitor) { 1880 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor,"Line search: Unable to find good step length! %D \n",count);CHKERRQ(ierr); 1881 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); 1882 } 1883 ierr = VecCopy(x,w);CHKERRQ(ierr); 1884 *flag = PETSC_FALSE; 1885 break; 1886 } 1887 lambdatemp = -initslope/((*gnorm)*(*gnorm) - fnorm*fnorm - 2.0*initslope); 1888 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 1889 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 1890 else lambda = lambdatemp; 1891 1892 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 1893 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1894 if (snes->nfuncs >= snes->max_funcs) { 1895 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while looking for good step length! %D \n",count);CHKERRQ(ierr); 1896 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); 1897 *flag = PETSC_FALSE; 1898 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1899 break; 1900 } 1901 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1902 if (snes->domainerror) { 1903 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1904 PetscFunctionReturn(0); 1905 } 1906 if (snes->ops->solve != SNESSolveVI_SS) { 1907 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1908 } else { 1909 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1910 } 1911 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1912 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* sufficient reduction */ 1913 if (vi->lsmonitor) { 1914 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line Search: Quadratically determined step, lambda=%G\n",lambda);CHKERRQ(ierr); 1915 } 1916 break; 1917 } 1918 count++; 1919 } 1920 theend2: 1921 /* Optional user-defined check for line search step validity */ 1922 if (vi->postcheckstep) { 1923 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1924 if (changed_y) { 1925 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1926 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1927 } 1928 if (changed_y || changed_w) { /* recompute the function if the step has changed */ 1929 ierr = SNESComputeFunction(snes,w,g); 1930 if (snes->domainerror) { 1931 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1932 PetscFunctionReturn(0); 1933 } 1934 if (snes->ops->solve != SNESSolveVI_SS) { 1935 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1936 } else { 1937 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1938 } 1939 1940 ierr = VecNormBegin(y,NORM_2,ynorm);CHKERRQ(ierr); 1941 ierr = VecNormEnd(y,NORM_2,ynorm);CHKERRQ(ierr); 1942 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1943 } 1944 } 1945 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1946 PetscFunctionReturn(0); 1947 } 1948 1949 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*/ 1950 /* -------------------------------------------------------------------------- */ 1951 EXTERN_C_BEGIN 1952 #undef __FUNCT__ 1953 #define __FUNCT__ "SNESLineSearchSet_VI" 1954 PetscErrorCode SNESLineSearchSet_VI(SNES snes,FCN2 func,void *lsctx) 1955 { 1956 PetscFunctionBegin; 1957 ((SNES_VI *)(snes->data))->LineSearch = func; 1958 ((SNES_VI *)(snes->data))->lsP = lsctx; 1959 PetscFunctionReturn(0); 1960 } 1961 EXTERN_C_END 1962 1963 /* -------------------------------------------------------------------------- */ 1964 EXTERN_C_BEGIN 1965 #undef __FUNCT__ 1966 #define __FUNCT__ "SNESLineSearchSetMonitor_VI" 1967 PetscErrorCode SNESLineSearchSetMonitor_VI(SNES snes,PetscBool flg) 1968 { 1969 SNES_VI *vi = (SNES_VI*)snes->data; 1970 PetscErrorCode ierr; 1971 1972 PetscFunctionBegin; 1973 if (flg && !vi->lsmonitor) { 1974 ierr = PetscViewerASCIIMonitorCreate(((PetscObject)snes)->comm,"stdout",((PetscObject)snes)->tablevel,&vi->lsmonitor);CHKERRQ(ierr); 1975 } else if (!flg && vi->lsmonitor) { 1976 ierr = PetscViewerASCIIMonitorDestroy(&vi->lsmonitor);CHKERRQ(ierr); 1977 } 1978 PetscFunctionReturn(0); 1979 } 1980 EXTERN_C_END 1981 1982 /* 1983 SNESView_VI - Prints info from the SNESVI data structure. 1984 1985 Input Parameters: 1986 . SNES - the SNES context 1987 . viewer - visualization context 1988 1989 Application Interface Routine: SNESView() 1990 */ 1991 #undef __FUNCT__ 1992 #define __FUNCT__ "SNESView_VI" 1993 static PetscErrorCode SNESView_VI(SNES snes,PetscViewer viewer) 1994 { 1995 SNES_VI *vi = (SNES_VI *)snes->data; 1996 const char *cstr,*tstr; 1997 PetscErrorCode ierr; 1998 PetscBool iascii; 1999 2000 PetscFunctionBegin; 2001 ierr = PetscTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr); 2002 if (iascii) { 2003 if (vi->LineSearch == SNESLineSearchNo_VI) cstr = "SNESLineSearchNo"; 2004 else if (vi->LineSearch == SNESLineSearchQuadratic_VI) cstr = "SNESLineSearchQuadratic"; 2005 else if (vi->LineSearch == SNESLineSearchCubic_VI) cstr = "SNESLineSearchCubic"; 2006 else cstr = "unknown"; 2007 if (snes->ops->solve == SNESSolveVI_SS) tstr = "Semismooth"; 2008 else if (snes->ops->solve == SNESSolveVI_RS) tstr = "Reduced Space"; 2009 else if (snes->ops->solve == SNESSolveVI_RS2) tstr = "Augmented Space"; 2010 else tstr = "unknown"; 2011 ierr = PetscViewerASCIIPrintf(viewer," VI algorithm: %s\n",tstr);CHKERRQ(ierr); 2012 ierr = PetscViewerASCIIPrintf(viewer," line search variant: %s\n",cstr);CHKERRQ(ierr); 2013 ierr = PetscViewerASCIIPrintf(viewer," alpha=%G, maxstep=%G, minlambda=%G\n",vi->alpha,vi->maxstep,vi->minlambda);CHKERRQ(ierr); 2014 } else { 2015 SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Viewer type %s not supported for SNES EQ VI",((PetscObject)viewer)->type_name); 2016 } 2017 PetscFunctionReturn(0); 2018 } 2019 2020 #undef __FUNCT__ 2021 #define __FUNCT__ "SNESVISetVariableBounds" 2022 /*@ 2023 SNESVISetVariableBounds - Sets the lower and upper bounds for the solution vector. xl <= x <= xu. 2024 2025 Input Parameters: 2026 . snes - the SNES context. 2027 . xl - lower bound. 2028 . xu - upper bound. 2029 2030 Notes: 2031 If this routine is not called then the lower and upper bounds are set to 2032 PETSC_VI_INF and PETSC_VI_NINF respectively during SNESSetUp(). 2033 2034 @*/ 2035 PetscErrorCode SNESVISetVariableBounds(SNES snes, Vec xl, Vec xu) 2036 { 2037 SNES_VI *vi = (SNES_VI*)snes->data; 2038 2039 PetscFunctionBegin; 2040 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 2041 PetscValidHeaderSpecific(xl,VEC_CLASSID,2); 2042 PetscValidHeaderSpecific(xu,VEC_CLASSID,3); 2043 if (!snes->vec_func) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call SNESSetFunction() first"); 2044 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); 2045 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); 2046 2047 vi->usersetxbounds = PETSC_TRUE; 2048 vi->xl = xl; 2049 vi->xu = xu; 2050 PetscFunctionReturn(0); 2051 } 2052 2053 /* -------------------------------------------------------------------------- */ 2054 /* 2055 SNESSetFromOptions_VI - Sets various parameters for the SNESVI method. 2056 2057 Input Parameter: 2058 . snes - the SNES context 2059 2060 Application Interface Routine: SNESSetFromOptions() 2061 */ 2062 #undef __FUNCT__ 2063 #define __FUNCT__ "SNESSetFromOptions_VI" 2064 static PetscErrorCode SNESSetFromOptions_VI(SNES snes) 2065 { 2066 SNES_VI *vi = (SNES_VI *)snes->data; 2067 const char *lses[] = {"basic","basicnonorms","quadratic","cubic"}; 2068 const char *vies[] = {"ss","rs","rs2"}; 2069 PetscErrorCode ierr; 2070 PetscInt indx; 2071 PetscBool flg,set,flg2; 2072 2073 PetscFunctionBegin; 2074 ierr = PetscOptionsHead("SNES semismooth method options");CHKERRQ(ierr); 2075 ierr = PetscOptionsBool("-snes_vi_monitor","Monitor all non-active variables","None",PETSC_FALSE,&flg,0);CHKERRQ(ierr); 2076 if (flg) { 2077 ierr = SNESMonitorSet(snes,SNESMonitorVI,0,0);CHKERRQ(ierr); 2078 } 2079 ierr = PetscOptionsReal("-snes_ls_alpha","Function norm must decrease by","None",vi->alpha,&vi->alpha,0);CHKERRQ(ierr); 2080 ierr = PetscOptionsReal("-snes_ls_maxstep","Step must be less than","None",vi->maxstep,&vi->maxstep,0);CHKERRQ(ierr); 2081 ierr = PetscOptionsReal("-snes_ls_minlambda","Minimum lambda allowed","None",vi->minlambda,&vi->minlambda,0);CHKERRQ(ierr); 2082 ierr = PetscOptionsReal("-snes_vi_const_tol","constraint tolerance","None",vi->const_tol,&vi->const_tol,0);CHKERRQ(ierr); 2083 ierr = PetscOptionsBool("-snes_ls_monitor","Print progress of line searches","SNESLineSearchSetMonitor",vi->lsmonitor ? PETSC_TRUE : PETSC_FALSE,&flg,&set);CHKERRQ(ierr); 2084 if (set) {ierr = SNESLineSearchSetMonitor(snes,flg);CHKERRQ(ierr);} 2085 ierr = PetscOptionsEList("-snes_vi_type","Semismooth algorithm used","",vies,3,"ss",&indx,&flg2);CHKERRQ(ierr); 2086 if (flg2) { 2087 switch (indx) { 2088 case 0: 2089 snes->ops->solve = SNESSolveVI_SS; 2090 break; 2091 case 1: 2092 snes->ops->solve = SNESSolveVI_RS; 2093 break; 2094 case 2: 2095 snes->ops->solve = SNESSolveVI_RS2; 2096 } 2097 } 2098 ierr = PetscOptionsEList("-snes_ls","Line search used","SNESLineSearchSet",lses,4,"basic",&indx,&flg);CHKERRQ(ierr); 2099 if (flg) { 2100 switch (indx) { 2101 case 0: 2102 ierr = SNESLineSearchSet(snes,SNESLineSearchNo_VI,PETSC_NULL);CHKERRQ(ierr); 2103 break; 2104 case 1: 2105 ierr = SNESLineSearchSet(snes,SNESLineSearchNoNorms_VI,PETSC_NULL);CHKERRQ(ierr); 2106 break; 2107 case 2: 2108 ierr = SNESLineSearchSet(snes,SNESLineSearchQuadratic_VI,PETSC_NULL);CHKERRQ(ierr); 2109 break; 2110 case 3: 2111 ierr = SNESLineSearchSet(snes,SNESLineSearchCubic_VI,PETSC_NULL);CHKERRQ(ierr); 2112 break; 2113 } 2114 } 2115 ierr = PetscOptionsTail();CHKERRQ(ierr); 2116 PetscFunctionReturn(0); 2117 } 2118 /* -------------------------------------------------------------------------- */ 2119 /*MC 2120 SNESVI - Semismooth newton method based nonlinear solver that uses a line search 2121 2122 Options Database: 2123 + -snes_ls [cubic,quadratic,basic,basicnonorms] - Selects line search 2124 . -snes_ls_alpha <alpha> - Sets alpha 2125 . -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) 2126 . -snes_ls_minlambda <minlambda> - Sets the minimum lambda the line search will use minlambda / max_i ( y[i]/x[i] ) 2127 - -snes_ls_monitor - print information about progress of line searches 2128 2129 2130 Level: beginner 2131 2132 .seealso: SNESCreate(), SNES, SNESSetType(), SNESTR, SNESLineSearchSet(), 2133 SNESLineSearchSetPostCheck(), SNESLineSearchNo(), SNESLineSearchCubic(), SNESLineSearchQuadratic(), 2134 SNESLineSearchSet(), SNESLineSearchNoNorms(), SNESLineSearchSetPreCheck(), SNESLineSearchSetParams(), SNESLineSearchGetParams() 2135 2136 M*/ 2137 EXTERN_C_BEGIN 2138 #undef __FUNCT__ 2139 #define __FUNCT__ "SNESCreate_VI" 2140 PetscErrorCode SNESCreate_VI(SNES snes) 2141 { 2142 PetscErrorCode ierr; 2143 SNES_VI *vi; 2144 2145 PetscFunctionBegin; 2146 snes->ops->setup = SNESSetUp_VI; 2147 snes->ops->solve = SNESSolveVI_SS; 2148 snes->ops->destroy = SNESDestroy_VI; 2149 snes->ops->setfromoptions = SNESSetFromOptions_VI; 2150 snes->ops->view = SNESView_VI; 2151 snes->ops->reset = 0; /* XXX Implement!!! */ 2152 snes->ops->converged = SNESDefaultConverged_VI; 2153 2154 ierr = PetscNewLog(snes,SNES_VI,&vi);CHKERRQ(ierr); 2155 snes->data = (void*)vi; 2156 vi->alpha = 1.e-4; 2157 vi->maxstep = 1.e8; 2158 vi->minlambda = 1.e-12; 2159 vi->LineSearch = SNESLineSearchNo_VI; 2160 vi->lsP = PETSC_NULL; 2161 vi->postcheckstep = PETSC_NULL; 2162 vi->postcheck = PETSC_NULL; 2163 vi->precheckstep = PETSC_NULL; 2164 vi->precheck = PETSC_NULL; 2165 vi->const_tol = 2.2204460492503131e-16; 2166 vi->checkredundancy = PETSC_NULL; 2167 2168 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSetMonitor_C","SNESLineSearchSetMonitor_VI",SNESLineSearchSetMonitor_VI);CHKERRQ(ierr); 2169 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSet_C","SNESLineSearchSet_VI",SNESLineSearchSet_VI);CHKERRQ(ierr); 2170 2171 PetscFunctionReturn(0); 2172 } 2173 EXTERN_C_END 2174