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] <= SNES_VI_NINF) && (u[i] >= SNES_VI_INF)) { /* no constraints on variable */ 230 phi_arr[i] = f_arr[i]; 231 } else if (l[i] <= SNES_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] >= SNES_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] <= SNES_VI_NINF) && (u[i] >= SNES_VI_INF)) {/* no constraints on variable */ 275 da[i] = 0; 276 db[i] = 1; 277 } else if (l[i] <= SNES_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] >= SNES_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 ierr = SNESGetKSP(snes,&snesksp);CHKERRQ(ierr); 697 698 ierr = KSPReset(snesksp);CHKERRQ(ierr); 699 /* 700 701 ierr = KSPCreate(((PetscObject)snes)->comm,&kspnew);CHKERRQ(ierr); 702 kspnew->pc_side = snesksp->pc_side; 703 kspnew->rtol = snesksp->rtol; 704 kspnew->abstol = snesksp->abstol; 705 kspnew->max_it = snesksp->max_it; 706 ierr = KSPSetType(kspnew,((PetscObject)snesksp)->type_name);CHKERRQ(ierr); 707 ierr = KSPGetPC(kspnew,&pcnew);CHKERRQ(ierr); 708 ierr = PCSetType(kspnew->pc,((PetscObject)snesksp->pc)->type_name);CHKERRQ(ierr); 709 ierr = PCSetOperators(kspnew->pc,Amat,Pmat,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr); 710 ierr = PCFactorGetMatSolverPackage(snesksp->pc,&stype);CHKERRQ(ierr); 711 ierr = PCFactorSetMatSolverPackage(kspnew->pc,stype);CHKERRQ(ierr); 712 ierr = KSPDestroy(&snesksp);CHKERRQ(ierr); 713 snes->ksp = kspnew; 714 ierr = PetscLogObjectParent(snes,kspnew);CHKERRQ(ierr); 715 ierr = KSPSetFromOptions(kspnew);CHKERRQ(ierr);*/ 716 PetscFunctionReturn(0); 717 } 718 719 720 #undef __FUNCT__ 721 #define __FUNCT__ "SNESVIComputeInactiveSetFnorm" 722 PetscErrorCode SNESVIComputeInactiveSetFnorm(SNES snes,Vec F,Vec X,PetscScalar *fnorm) 723 { 724 PetscErrorCode ierr; 725 SNES_VI *vi = (SNES_VI*)snes->data; 726 const PetscScalar *x,*xl,*xu,*f; 727 PetscInt i,n; 728 PetscReal rnorm; 729 730 PetscFunctionBegin; 731 ierr = VecGetLocalSize(X,&n);CHKERRQ(ierr); 732 ierr = VecGetArrayRead(vi->xl,&xl);CHKERRQ(ierr); 733 ierr = VecGetArrayRead(vi->xu,&xu);CHKERRQ(ierr); 734 ierr = VecGetArrayRead(X,&x);CHKERRQ(ierr); 735 ierr = VecGetArrayRead(F,&f);CHKERRQ(ierr); 736 rnorm = 0.0; 737 for (i=0; i<n; i++) { 738 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]; 739 } 740 ierr = VecRestoreArrayRead(F,&f);CHKERRQ(ierr); 741 ierr = VecRestoreArrayRead(vi->xl,&xl);CHKERRQ(ierr); 742 ierr = VecRestoreArrayRead(vi->xu,&xu);CHKERRQ(ierr); 743 ierr = VecRestoreArrayRead(X,&x);CHKERRQ(ierr); 744 ierr = MPI_Allreduce(&rnorm,fnorm,1,MPIU_REAL,MPIU_SUM,((PetscObject)snes)->comm);CHKERRQ(ierr); 745 *fnorm = sqrt(*fnorm); 746 PetscFunctionReturn(0); 747 } 748 749 /* Variational Inequality solver using reduce space method. No semismooth algorithm is 750 implemented in this algorithm. It basically identifies the active constraints and does 751 a linear solve on the other variables (those not associated with the active constraints). */ 752 #undef __FUNCT__ 753 #define __FUNCT__ "SNESSolveVI_RS" 754 PetscErrorCode SNESSolveVI_RS(SNES snes) 755 { 756 SNES_VI *vi = (SNES_VI*)snes->data; 757 PetscErrorCode ierr; 758 PetscInt maxits,i,lits; 759 PetscBool lssucceed; 760 MatStructure flg = DIFFERENT_NONZERO_PATTERN; 761 PetscReal fnorm,gnorm,xnorm=0,ynorm; 762 Vec Y,X,F,G,W; 763 KSPConvergedReason kspreason; 764 765 PetscFunctionBegin; 766 snes->numFailures = 0; 767 snes->numLinearSolveFailures = 0; 768 snes->reason = SNES_CONVERGED_ITERATING; 769 770 maxits = snes->max_its; /* maximum number of iterations */ 771 X = snes->vec_sol; /* solution vector */ 772 F = snes->vec_func; /* residual vector */ 773 Y = snes->work[0]; /* work vectors */ 774 G = snes->work[1]; 775 W = snes->work[2]; 776 777 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 778 snes->iter = 0; 779 snes->norm = 0.0; 780 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 781 782 ierr = SNESVIProjectOntoBounds(snes,X);CHKERRQ(ierr); 783 ierr = SNESComputeFunction(snes,X,F);CHKERRQ(ierr); 784 if (snes->domainerror) { 785 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 786 PetscFunctionReturn(0); 787 } 788 ierr = SNESVIComputeInactiveSetFnorm(snes,F,X,&fnorm);CHKERRQ(ierr); 789 ierr = VecNormBegin(X,NORM_2,&xnorm);CHKERRQ(ierr); /* xnorm <- ||x|| */ 790 ierr = VecNormEnd(X,NORM_2,&xnorm);CHKERRQ(ierr); 791 if (PetscIsInfOrNanReal(fnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 792 793 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 794 snes->norm = fnorm; 795 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 796 SNESLogConvHistory(snes,fnorm,0); 797 ierr = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr); 798 799 /* set parameter for default relative tolerance convergence test */ 800 snes->ttol = fnorm*snes->rtol; 801 /* test convergence */ 802 ierr = (*snes->ops->converged)(snes,0,0.0,0.0,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 803 if (snes->reason) PetscFunctionReturn(0); 804 805 for (i=0; i<maxits; i++) { 806 807 IS IS_act,IS_inact; /* _act -> active set _inact -> inactive set */ 808 VecScatter scat_act,scat_inact; 809 PetscInt nis_act,nis_inact; 810 Vec Y_act,Y_inact,F_inact; 811 Mat jac_inact_inact,prejac_inact_inact; 812 IS keptrows; 813 PetscBool isequal; 814 815 /* Call general purpose update function */ 816 if (snes->ops->update) { 817 ierr = (*snes->ops->update)(snes, snes->iter);CHKERRQ(ierr); 818 } 819 ierr = SNESComputeJacobian(snes,X,&snes->jacobian,&snes->jacobian_pre,&flg);CHKERRQ(ierr); 820 821 /* Create active and inactive index sets */ 822 ierr = SNESVICreateIndexSets_RS(snes,X,F,&IS_act,&IS_inact);CHKERRQ(ierr); 823 824 /* Create inactive set submatrix */ 825 ierr = MatGetSubMatrix(snes->jacobian,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);CHKERRQ(ierr); 826 ierr = MatFindNonzeroRows(jac_inact_inact,&keptrows);CHKERRQ(ierr); 827 if (keptrows) { 828 PetscInt cnt,*nrows,k; 829 const PetscInt *krows,*inact; 830 PetscInt rstart=jac_inact_inact->rmap->rstart; 831 832 ierr = MatDestroy(&jac_inact_inact);CHKERRQ(ierr); 833 ierr = ISDestroy(&IS_act);CHKERRQ(ierr); 834 835 ierr = ISGetLocalSize(keptrows,&cnt);CHKERRQ(ierr); 836 ierr = ISGetIndices(keptrows,&krows);CHKERRQ(ierr); 837 ierr = ISGetIndices(IS_inact,&inact);CHKERRQ(ierr); 838 ierr = PetscMalloc(cnt*sizeof(PetscInt),&nrows);CHKERRQ(ierr); 839 for (k=0; k<cnt; k++) { 840 nrows[k] = inact[krows[k]-rstart]; 841 } 842 ierr = ISRestoreIndices(keptrows,&krows);CHKERRQ(ierr); 843 ierr = ISRestoreIndices(IS_inact,&inact);CHKERRQ(ierr); 844 ierr = ISDestroy(&keptrows);CHKERRQ(ierr); 845 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 846 847 ierr = ISCreateGeneral(PETSC_COMM_WORLD,cnt,nrows,PETSC_OWN_POINTER,&IS_inact);CHKERRQ(ierr); 848 ierr = ISComplement(IS_inact,F->map->rstart,F->map->rend,&IS_act);CHKERRQ(ierr); 849 ierr = MatGetSubMatrix(snes->jacobian,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&jac_inact_inact);CHKERRQ(ierr); 850 } 851 852 /* Get sizes of active and inactive sets */ 853 ierr = ISGetLocalSize(IS_act,&nis_act);CHKERRQ(ierr); 854 ierr = ISGetLocalSize(IS_inact,&nis_inact);CHKERRQ(ierr); 855 856 /* Create active and inactive set vectors */ 857 ierr = SNESVICreateSubVectors(snes,nis_inact,&F_inact);CHKERRQ(ierr); 858 ierr = SNESVICreateSubVectors(snes,nis_act,&Y_act);CHKERRQ(ierr); 859 ierr = SNESVICreateSubVectors(snes,nis_inact,&Y_inact);CHKERRQ(ierr); 860 861 /* Create scatter contexts */ 862 ierr = VecScatterCreate(Y,IS_act,Y_act,PETSC_NULL,&scat_act);CHKERRQ(ierr); 863 ierr = VecScatterCreate(Y,IS_inact,Y_inact,PETSC_NULL,&scat_inact);CHKERRQ(ierr); 864 865 /* Do a vec scatter to active and inactive set vectors */ 866 ierr = VecScatterBegin(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 867 ierr = VecScatterEnd(scat_inact,F,F_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 868 869 ierr = VecScatterBegin(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 870 ierr = VecScatterEnd(scat_act,Y,Y_act,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 871 872 ierr = VecScatterBegin(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 873 ierr = VecScatterEnd(scat_inact,Y,Y_inact,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); 874 875 /* Active set direction = 0 */ 876 ierr = VecSet(Y_act,0);CHKERRQ(ierr); 877 if (snes->jacobian != snes->jacobian_pre) { 878 ierr = MatGetSubMatrix(snes->jacobian_pre,IS_inact,IS_inact,MAT_INITIAL_MATRIX,&prejac_inact_inact);CHKERRQ(ierr); 879 } else prejac_inact_inact = jac_inact_inact; 880 881 ierr = ISEqual(vi->IS_inact_prev,IS_inact,&isequal);CHKERRQ(ierr); 882 if (!isequal) { 883 ierr = SNESVIResetPCandKSP(snes,jac_inact_inact,prejac_inact_inact);CHKERRQ(ierr); 884 } 885 886 /* ierr = ISView(IS_inact,0);CHKERRQ(ierr); */ 887 /* ierr = ISView(IS_act,0);CHKERRQ(ierr);*/ 888 /* ierr = MatView(snes->jacobian_pre,0); */ 889 890 ierr = KSPSetOperators(snes->ksp,jac_inact_inact,prejac_inact_inact,flg);CHKERRQ(ierr); 891 ierr = KSPSetUp(snes->ksp);CHKERRQ(ierr); 892 { 893 PC pc; 894 PetscBool flg; 895 ierr = KSPGetPC(snes->ksp,&pc);CHKERRQ(ierr); 896 ierr = PetscTypeCompare((PetscObject)pc,PCFIELDSPLIT,&flg);CHKERRQ(ierr); 897 if (flg) { 898 KSP *subksps; 899 ierr = PCFieldSplitGetSubKSP(pc,PETSC_NULL,&subksps);CHKERRQ(ierr); 900 ierr = KSPGetPC(subksps[0],&pc);CHKERRQ(ierr); 901 ierr = PetscFree(subksps);CHKERRQ(ierr); 902 ierr = PetscTypeCompare((PetscObject)pc,PCBJACOBI,&flg);CHKERRQ(ierr); 903 if (flg) { 904 PetscInt n,N = 101*101,j,cnts[3] = {0,0,0}; 905 const PetscInt *ii; 906 907 ierr = ISGetSize(IS_inact,&n);CHKERRQ(ierr); 908 ierr = ISGetIndices(IS_inact,&ii);CHKERRQ(ierr); 909 for (j=0; j<n; j++) { 910 if (ii[j] < N) cnts[0]++; 911 else if (ii[j] < 2*N) cnts[1]++; 912 else if (ii[j] < 3*N) cnts[2]++; 913 } 914 ierr = ISRestoreIndices(IS_inact,&ii);CHKERRQ(ierr); 915 916 ierr = PCBJacobiSetTotalBlocks(pc,3,cnts);CHKERRQ(ierr); 917 } 918 } 919 } 920 921 ierr = SNES_KSPSolve(snes,snes->ksp,F_inact,Y_inact);CHKERRQ(ierr); 922 ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr); 923 if (kspreason < 0) { 924 if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) { 925 ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr); 926 snes->reason = SNES_DIVERGED_LINEAR_SOLVE; 927 break; 928 } 929 } 930 931 ierr = VecScatterBegin(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 932 ierr = VecScatterEnd(scat_act,Y_act,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 933 ierr = VecScatterBegin(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 934 ierr = VecScatterEnd(scat_inact,Y_inact,Y,INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); 935 936 ierr = VecDestroy(&F_inact);CHKERRQ(ierr); 937 ierr = VecDestroy(&Y_act);CHKERRQ(ierr); 938 ierr = VecDestroy(&Y_inact);CHKERRQ(ierr); 939 ierr = VecScatterDestroy(&scat_act);CHKERRQ(ierr); 940 ierr = VecScatterDestroy(&scat_inact);CHKERRQ(ierr); 941 ierr = ISDestroy(&IS_act);CHKERRQ(ierr); 942 if (!isequal) { 943 ierr = ISDestroy(&vi->IS_inact_prev);CHKERRQ(ierr); 944 ierr = ISDuplicate(IS_inact,&vi->IS_inact_prev);CHKERRQ(ierr); 945 } 946 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 947 ierr = MatDestroy(&jac_inact_inact);CHKERRQ(ierr); 948 if (snes->jacobian != snes->jacobian_pre) { 949 ierr = MatDestroy(&prejac_inact_inact);CHKERRQ(ierr); 950 } 951 ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr); 952 snes->linear_its += lits; 953 ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr); 954 /* 955 if (vi->precheckstep) { 956 PetscBool changed_y = PETSC_FALSE; 957 ierr = (*vi->precheckstep)(snes,X,Y,vi->precheck,&changed_y);CHKERRQ(ierr); 958 } 959 960 if (PetscLogPrintInfo){ 961 ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr); 962 } 963 */ 964 /* Compute a (scaled) negative update in the line search routine: 965 Y <- X - lambda*Y 966 and evaluate G = function(Y) (depends on the line search). 967 */ 968 ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr); 969 ynorm = 1; gnorm = fnorm; 970 ierr = (*vi->LineSearch)(snes,vi->lsP,X,F,G,Y,W,fnorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr); 971 ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",fnorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr); 972 if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break; 973 if (snes->domainerror) { 974 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 975 PetscFunctionReturn(0); 976 } 977 if (!lssucceed) { 978 if (++snes->numFailures >= snes->maxFailures) { 979 PetscBool ismin; 980 snes->reason = SNES_DIVERGED_LINE_SEARCH; 981 ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr); 982 if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN; 983 break; 984 } 985 } 986 /* Update function and solution vectors */ 987 fnorm = gnorm; 988 ierr = VecCopy(G,F);CHKERRQ(ierr); 989 ierr = VecCopy(W,X);CHKERRQ(ierr); 990 /* Monitor convergence */ 991 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 992 snes->iter = i+1; 993 snes->norm = fnorm; 994 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 995 SNESLogConvHistory(snes,snes->norm,lits); 996 ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr); 997 /* Test for convergence, xnorm = || X || */ 998 if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); } 999 ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1000 if (snes->reason) break; 1001 } 1002 if (i == maxits) { 1003 ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr); 1004 if(!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT; 1005 } 1006 PetscFunctionReturn(0); 1007 } 1008 1009 #undef __FUNCT__ 1010 #define __FUNCT__ "SNESVISetRedundancyCheck" 1011 PetscErrorCode SNESVISetRedundancyCheck(SNES snes,PetscErrorCode (*func)(SNES,IS,IS*,void*),void *ctx) 1012 { 1013 SNES_VI *vi = (SNES_VI*)snes->data; 1014 1015 PetscFunctionBegin; 1016 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 1017 vi->checkredundancy = func; 1018 vi->ctxP = ctx; 1019 PetscFunctionReturn(0); 1020 } 1021 1022 #if defined(PETSC_HAVE_MATLAB_ENGINE) 1023 #include <engine.h> 1024 #include <mex.h> 1025 typedef struct {char *funcname; mxArray *ctx;} SNESMatlabContext; 1026 1027 #undef __FUNCT__ 1028 #define __FUNCT__ "SNESVIRedundancyCheck_Matlab" 1029 PetscErrorCode SNESVIRedundancyCheck_Matlab(SNES snes,IS is_act,IS* is_redact,void* ctx) 1030 { 1031 PetscErrorCode ierr; 1032 SNESMatlabContext *sctx = (SNESMatlabContext*)ctx; 1033 int nlhs = 1, nrhs = 5; 1034 mxArray *plhs[1], *prhs[5]; 1035 long long int l1 = 0, l2 = 0, ls = 0; 1036 PetscInt *indices=PETSC_NULL; 1037 1038 PetscFunctionBegin; 1039 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 1040 PetscValidHeaderSpecific(is_act,IS_CLASSID,2); 1041 PetscValidPointer(is_redact,3); 1042 PetscCheckSameComm(snes,1,is_act,2); 1043 1044 /* Create IS for reduced active set of size 0, its size and indices will 1045 bet set by the Matlab function */ 1046 ierr = ISCreateGeneral(((PetscObject)snes)->comm,0,indices,PETSC_OWN_POINTER,is_redact);CHKERRQ(ierr); 1047 /* call Matlab function in ctx */ 1048 ierr = PetscMemcpy(&ls,&snes,sizeof(snes));CHKERRQ(ierr); 1049 ierr = PetscMemcpy(&l1,&is_act,sizeof(is_act));CHKERRQ(ierr); 1050 ierr = PetscMemcpy(&l2,is_redact,sizeof(is_act));CHKERRQ(ierr); 1051 prhs[0] = mxCreateDoubleScalar((double)ls); 1052 prhs[1] = mxCreateDoubleScalar((double)l1); 1053 prhs[2] = mxCreateDoubleScalar((double)l2); 1054 prhs[3] = mxCreateString(sctx->funcname); 1055 prhs[4] = sctx->ctx; 1056 ierr = mexCallMATLAB(nlhs,plhs,nrhs,prhs,"PetscSNESVIRedundancyCheckInternal");CHKERRQ(ierr); 1057 ierr = mxGetScalar(plhs[0]);CHKERRQ(ierr); 1058 mxDestroyArray(prhs[0]); 1059 mxDestroyArray(prhs[1]); 1060 mxDestroyArray(prhs[2]); 1061 mxDestroyArray(prhs[3]); 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 ierr = SNESMonitor(snes,0,fnorm);CHKERRQ(ierr); 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=0; /* 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 ierr = PetscMalloc(nis_act*sizeof(PetscInt),&idx_actkept);CHKERRQ(ierr); 1180 for(k=0;k < nis_act;k++) idx_actkept[k] = idx_act[k]; 1181 nkept = nis_act; 1182 } else { 1183 ierr = ISGetLocalSize(IS_redact,&nis_redact);CHKERRQ(ierr); 1184 ierr = PetscMalloc((nis_act-nis_redact)*sizeof(PetscInt),&idx_actkept);CHKERRQ(ierr); 1185 1186 /* Create reduced active set list */ 1187 ierr = ISGetIndices(IS_act,&idx_act);CHKERRQ(ierr); 1188 ierr = ISGetIndices(IS_redact,&idx_redact);CHKERRQ(ierr); 1189 j1 = 0;nkept = 0; 1190 for(k=0;k<nis_act;k++) { 1191 if(j1 < nis_redact && idx_act[k] == idx_redact[j1]) j1++; 1192 else idx_actkept[nkept++] = idx_act[k]; 1193 } 1194 ierr = ISRestoreIndices(IS_act,&idx_act);CHKERRQ(ierr); 1195 ierr = ISRestoreIndices(IS_redact,&idx_redact);CHKERRQ(ierr); 1196 1197 ierr = ISDestroy(&IS_redact);CHKERRQ(ierr); 1198 } 1199 1200 /* Create augmented F and Y */ 1201 ierr = VecCreate(((PetscObject)snes)->comm,&F_aug);CHKERRQ(ierr); 1202 ierr = VecSetSizes(F_aug,F->map->n+nkept,PETSC_DECIDE);CHKERRQ(ierr); 1203 ierr = VecSetFromOptions(F_aug);CHKERRQ(ierr); 1204 ierr = VecDuplicate(F_aug,&Y_aug);CHKERRQ(ierr); 1205 1206 /* Copy over F to F_aug in the first n locations */ 1207 ierr = VecGetArray(F,&f);CHKERRQ(ierr); 1208 ierr = VecGetArray(F_aug,&f2);CHKERRQ(ierr); 1209 ierr = PetscMemcpy(f2,f,F->map->n*sizeof(PetscScalar));CHKERRQ(ierr); 1210 ierr = VecRestoreArray(F,&f);CHKERRQ(ierr); 1211 ierr = VecRestoreArray(F_aug,&f2);CHKERRQ(ierr); 1212 1213 /* Create the augmented jacobian matrix */ 1214 ierr = MatCreate(((PetscObject)snes)->comm,&J_aug);CHKERRQ(ierr); 1215 ierr = MatSetSizes(J_aug,X->map->n+nkept,X->map->n+nkept,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr); 1216 ierr = MatSetFromOptions(J_aug);CHKERRQ(ierr); 1217 1218 1219 { /* local vars */ 1220 /* Preallocate augmented matrix and set values in it...Doing only sequential case first*/ 1221 PetscInt ncols; 1222 const PetscInt *cols; 1223 const PetscScalar *vals; 1224 PetscScalar value[2]; 1225 PetscInt row,col[2]; 1226 PetscInt *d_nnz; 1227 value[0] = 1.0; value[1] = 0.0; 1228 ierr = PetscMalloc((X->map->n+nkept)*sizeof(PetscInt),&d_nnz);CHKERRQ(ierr); 1229 ierr = PetscMemzero(d_nnz,(X->map->n+nkept)*sizeof(PetscInt));CHKERRQ(ierr); 1230 for(row=0;row<snes->jacobian->rmap->n;row++) { 1231 ierr = MatGetRow(snes->jacobian,row,&ncols,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr); 1232 d_nnz[row] += ncols; 1233 ierr = MatRestoreRow(snes->jacobian,row,&ncols,PETSC_NULL,PETSC_NULL);CHKERRQ(ierr); 1234 } 1235 1236 for(k=0;k<nkept;k++) { 1237 d_nnz[idx_actkept[k]] += 1; 1238 d_nnz[snes->jacobian->rmap->n+k] += 2; 1239 } 1240 ierr = MatSeqAIJSetPreallocation(J_aug,PETSC_NULL,d_nnz);CHKERRQ(ierr); 1241 1242 ierr = PetscFree(d_nnz);CHKERRQ(ierr); 1243 1244 /* Set the original jacobian matrix in J_aug */ 1245 for(row=0;row<snes->jacobian->rmap->n;row++) { 1246 ierr = MatGetRow(snes->jacobian,row,&ncols,&cols,&vals);CHKERRQ(ierr); 1247 ierr = MatSetValues(J_aug,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr); 1248 ierr = MatRestoreRow(snes->jacobian,row,&ncols,&cols,&vals);CHKERRQ(ierr); 1249 } 1250 /* Add the augmented part */ 1251 for(k=0;k<nkept;k++) { 1252 row = snes->jacobian->rmap->n+k; 1253 col[0] = idx_actkept[k]; col[1] = snes->jacobian->rmap->n+k; 1254 ierr = MatSetValues(J_aug,1,&row,1,col,value,INSERT_VALUES);CHKERRQ(ierr); 1255 ierr = MatSetValues(J_aug,1,&col[0],1,&row,&value[0],INSERT_VALUES);CHKERRQ(ierr); 1256 } 1257 ierr = MatAssemblyBegin(J_aug,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 1258 ierr = MatAssemblyEnd(J_aug,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); 1259 /* Only considering prejac = jac for now */ 1260 Jpre_aug = J_aug; 1261 } /* local vars*/ 1262 } else { 1263 F_aug = F; J_aug = snes->jacobian; Y_aug = Y; Jpre_aug = snes->jacobian_pre; 1264 } 1265 1266 ierr = ISEqual(vi->IS_inact_prev,IS_inact,&isequal);CHKERRQ(ierr); 1267 if (!isequal) { 1268 ierr = SNESVIResetPCandKSP(snes,J_aug,Jpre_aug);CHKERRQ(ierr); 1269 } 1270 ierr = KSPSetOperators(snes->ksp,J_aug,Jpre_aug,flg);CHKERRQ(ierr); 1271 ierr = KSPSetUp(snes->ksp);CHKERRQ(ierr); 1272 /* { 1273 PC pc; 1274 PetscBool flg; 1275 ierr = KSPGetPC(snes->ksp,&pc);CHKERRQ(ierr); 1276 ierr = PetscTypeCompare((PetscObject)pc,PCFIELDSPLIT,&flg);CHKERRQ(ierr); 1277 if (flg) { 1278 KSP *subksps; 1279 ierr = PCFieldSplitGetSubKSP(pc,PETSC_NULL,&subksps);CHKERRQ(ierr); 1280 ierr = KSPGetPC(subksps[0],&pc);CHKERRQ(ierr); 1281 ierr = PetscFree(subksps);CHKERRQ(ierr); 1282 ierr = PetscTypeCompare((PetscObject)pc,PCBJACOBI,&flg);CHKERRQ(ierr); 1283 if (flg) { 1284 PetscInt n,N = 101*101,j,cnts[3] = {0,0,0}; 1285 const PetscInt *ii; 1286 1287 ierr = ISGetSize(IS_inact,&n);CHKERRQ(ierr); 1288 ierr = ISGetIndices(IS_inact,&ii);CHKERRQ(ierr); 1289 for (j=0; j<n; j++) { 1290 if (ii[j] < N) cnts[0]++; 1291 else if (ii[j] < 2*N) cnts[1]++; 1292 else if (ii[j] < 3*N) cnts[2]++; 1293 } 1294 ierr = ISRestoreIndices(IS_inact,&ii);CHKERRQ(ierr); 1295 1296 ierr = PCBJacobiSetTotalBlocks(pc,3,cnts);CHKERRQ(ierr); 1297 } 1298 } 1299 } 1300 */ 1301 ierr = SNES_KSPSolve(snes,snes->ksp,F_aug,Y_aug);CHKERRQ(ierr); 1302 ierr = KSPGetConvergedReason(snes->ksp,&kspreason);CHKERRQ(ierr); 1303 if (kspreason < 0) { 1304 if (++snes->numLinearSolveFailures >= snes->maxLinearSolveFailures) { 1305 ierr = PetscInfo2(snes,"iter=%D, number linear solve failures %D greater than current SNES allowed, stopping solve\n",snes->iter,snes->numLinearSolveFailures);CHKERRQ(ierr); 1306 snes->reason = SNES_DIVERGED_LINEAR_SOLVE; 1307 break; 1308 } 1309 } 1310 1311 if(nis_act) { 1312 PetscScalar *y1,*y2; 1313 ierr = VecGetArray(Y,&y1);CHKERRQ(ierr); 1314 ierr = VecGetArray(Y_aug,&y2);CHKERRQ(ierr); 1315 /* Copy over inactive Y_aug to Y */ 1316 j1 = 0; 1317 for(i1=Y->map->rstart;i1 < Y->map->rend;i1++) { 1318 if(j1 < nkept && idx_actkept[j1] == i1) j1++; 1319 else y1[i1-Y->map->rstart] = y2[i1-Y->map->rstart]; 1320 } 1321 ierr = VecRestoreArray(Y,&y1);CHKERRQ(ierr); 1322 ierr = VecRestoreArray(Y_aug,&y2);CHKERRQ(ierr); 1323 1324 ierr = VecDestroy(&F_aug);CHKERRQ(ierr); 1325 ierr = VecDestroy(&Y_aug);CHKERRQ(ierr); 1326 ierr = MatDestroy(&J_aug);CHKERRQ(ierr); 1327 ierr = PetscFree(idx_actkept);CHKERRQ(ierr); 1328 } 1329 1330 if (!isequal) { 1331 ierr = ISDestroy(&vi->IS_inact_prev);CHKERRQ(ierr); 1332 ierr = ISDuplicate(IS_inact,&vi->IS_inact_prev);CHKERRQ(ierr); 1333 } 1334 ierr = ISDestroy(&IS_inact);CHKERRQ(ierr); 1335 1336 ierr = KSPGetIterationNumber(snes->ksp,&lits);CHKERRQ(ierr); 1337 snes->linear_its += lits; 1338 ierr = PetscInfo2(snes,"iter=%D, linear solve iterations=%D\n",snes->iter,lits);CHKERRQ(ierr); 1339 /* 1340 if (vi->precheckstep) { 1341 PetscBool changed_y = PETSC_FALSE; 1342 ierr = (*vi->precheckstep)(snes,X,Y,vi->precheck,&changed_y);CHKERRQ(ierr); 1343 } 1344 1345 if (PetscLogPrintInfo){ 1346 ierr = SNESVICheckResidual_Private(snes,snes->jacobian,F,Y,G,W);CHKERRQ(ierr); 1347 } 1348 */ 1349 /* Compute a (scaled) negative update in the line search routine: 1350 Y <- X - lambda*Y 1351 and evaluate G = function(Y) (depends on the line search). 1352 */ 1353 ierr = VecCopy(Y,snes->vec_sol_update);CHKERRQ(ierr); 1354 ynorm = 1; gnorm = fnorm; 1355 ierr = (*vi->LineSearch)(snes,vi->lsP,X,F,G,Y,W,fnorm,xnorm,&ynorm,&gnorm,&lssucceed);CHKERRQ(ierr); 1356 ierr = PetscInfo4(snes,"fnorm=%18.16e, gnorm=%18.16e, ynorm=%18.16e, lssucceed=%d\n",fnorm,gnorm,ynorm,(int)lssucceed);CHKERRQ(ierr); 1357 if (snes->reason == SNES_DIVERGED_FUNCTION_COUNT) break; 1358 if (snes->domainerror) { 1359 snes->reason = SNES_DIVERGED_FUNCTION_DOMAIN; 1360 PetscFunctionReturn(0); 1361 } 1362 if (!lssucceed) { 1363 if (++snes->numFailures >= snes->maxFailures) { 1364 PetscBool ismin; 1365 snes->reason = SNES_DIVERGED_LINE_SEARCH; 1366 ierr = SNESVICheckLocalMin_Private(snes,snes->jacobian,G,W,gnorm,&ismin);CHKERRQ(ierr); 1367 if (ismin) snes->reason = SNES_DIVERGED_LOCAL_MIN; 1368 break; 1369 } 1370 } 1371 /* Update function and solution vectors */ 1372 fnorm = gnorm; 1373 ierr = VecCopy(G,F);CHKERRQ(ierr); 1374 ierr = VecCopy(W,X);CHKERRQ(ierr); 1375 /* Monitor convergence */ 1376 ierr = PetscObjectTakeAccess(snes);CHKERRQ(ierr); 1377 snes->iter = i+1; 1378 snes->norm = fnorm; 1379 ierr = PetscObjectGrantAccess(snes);CHKERRQ(ierr); 1380 SNESLogConvHistory(snes,snes->norm,lits); 1381 ierr = SNESMonitor(snes,snes->iter,snes->norm);CHKERRQ(ierr); 1382 /* Test for convergence, xnorm = || X || */ 1383 if (snes->ops->converged != SNESSkipConverged) { ierr = VecNorm(X,NORM_2,&xnorm);CHKERRQ(ierr); } 1384 ierr = (*snes->ops->converged)(snes,snes->iter,xnorm,ynorm,fnorm,&snes->reason,snes->cnvP);CHKERRQ(ierr); 1385 if (snes->reason) break; 1386 } 1387 if (i == maxits) { 1388 ierr = PetscInfo1(snes,"Maximum number of iterations has been reached: %D\n",maxits);CHKERRQ(ierr); 1389 if(!snes->reason) snes->reason = SNES_DIVERGED_MAX_IT; 1390 } 1391 PetscFunctionReturn(0); 1392 } 1393 1394 /* -------------------------------------------------------------------------- */ 1395 /* 1396 SNESSetUp_VI - Sets up the internal data structures for the later use 1397 of the SNESVI nonlinear solver. 1398 1399 Input Parameter: 1400 . snes - the SNES context 1401 . x - the solution vector 1402 1403 Application Interface Routine: SNESSetUp() 1404 1405 Notes: 1406 For basic use of the SNES solvers, the user need not explicitly call 1407 SNESSetUp(), since these actions will automatically occur during 1408 the call to SNESSolve(). 1409 */ 1410 #undef __FUNCT__ 1411 #define __FUNCT__ "SNESSetUp_VI" 1412 PetscErrorCode SNESSetUp_VI(SNES snes) 1413 { 1414 PetscErrorCode ierr; 1415 SNES_VI *vi = (SNES_VI*) snes->data; 1416 PetscInt i_start[3],i_end[3]; 1417 1418 PetscFunctionBegin; 1419 1420 ierr = SNESDefaultGetWork(snes,3);CHKERRQ(ierr); 1421 1422 /* If the lower and upper bound on variables are not set, set it to 1423 -Inf and Inf */ 1424 if (!vi->xl && !vi->xu) { 1425 vi->usersetxbounds = PETSC_FALSE; 1426 ierr = VecDuplicate(snes->vec_sol, &vi->xl); CHKERRQ(ierr); 1427 ierr = VecSet(vi->xl,SNES_VI_NINF);CHKERRQ(ierr); 1428 ierr = VecDuplicate(snes->vec_sol, &vi->xu); CHKERRQ(ierr); 1429 ierr = VecSet(vi->xu,SNES_VI_INF);CHKERRQ(ierr); 1430 } else { 1431 /* Check if lower bound, upper bound and solution vector distribution across the processors is identical */ 1432 ierr = VecGetOwnershipRange(snes->vec_sol,i_start,i_end);CHKERRQ(ierr); 1433 ierr = VecGetOwnershipRange(vi->xl,i_start+1,i_end+1);CHKERRQ(ierr); 1434 ierr = VecGetOwnershipRange(vi->xu,i_start+2,i_end+2);CHKERRQ(ierr); 1435 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])) 1436 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."); 1437 } 1438 if (snes->ops->solve != SNESSolveVI_SS) { 1439 /* Set up previous active index set for the first snes solve 1440 vi->IS_inact_prev = 0,1,2,....N */ 1441 PetscInt *indices; 1442 PetscInt i,n,rstart,rend; 1443 1444 ierr = VecGetOwnershipRange(snes->vec_sol,&rstart,&rend);CHKERRQ(ierr); 1445 ierr = VecGetLocalSize(snes->vec_sol,&n);CHKERRQ(ierr); 1446 ierr = PetscMalloc(n*sizeof(PetscInt),&indices);CHKERRQ(ierr); 1447 for(i=0;i < n; i++) indices[i] = rstart + i; 1448 ierr = ISCreateGeneral(((PetscObject)snes)->comm,n,indices,PETSC_OWN_POINTER,&vi->IS_inact_prev); 1449 } 1450 1451 if (snes->ops->solve == SNESSolveVI_SS) { 1452 ierr = VecDuplicate(snes->vec_sol, &vi->dpsi);CHKERRQ(ierr); 1453 ierr = VecDuplicate(snes->vec_sol, &vi->phi); CHKERRQ(ierr); 1454 ierr = VecDuplicate(snes->vec_sol, &vi->Da); CHKERRQ(ierr); 1455 ierr = VecDuplicate(snes->vec_sol, &vi->Db); CHKERRQ(ierr); 1456 ierr = VecDuplicate(snes->vec_sol, &vi->z);CHKERRQ(ierr); 1457 ierr = VecDuplicate(snes->vec_sol, &vi->t); CHKERRQ(ierr); 1458 } 1459 PetscFunctionReturn(0); 1460 } 1461 /* -------------------------------------------------------------------------- */ 1462 /* 1463 SNESDestroy_VI - Destroys the private SNES_VI context that was created 1464 with SNESCreate_VI(). 1465 1466 Input Parameter: 1467 . snes - the SNES context 1468 1469 Application Interface Routine: SNESDestroy() 1470 */ 1471 #undef __FUNCT__ 1472 #define __FUNCT__ "SNESDestroy_VI" 1473 PetscErrorCode SNESDestroy_VI(SNES snes) 1474 { 1475 SNES_VI *vi = (SNES_VI*) snes->data; 1476 PetscErrorCode ierr; 1477 1478 PetscFunctionBegin; 1479 if (snes->ops->solve != SNESSolveVI_SS) { 1480 ierr = ISDestroy(&vi->IS_inact_prev); 1481 } 1482 1483 if (snes->ops->solve == SNESSolveVI_SS) { 1484 /* clear vectors */ 1485 ierr = VecDestroy(&vi->dpsi);CHKERRQ(ierr); 1486 ierr = VecDestroy(&vi->phi); CHKERRQ(ierr); 1487 ierr = VecDestroy(&vi->Da); CHKERRQ(ierr); 1488 ierr = VecDestroy(&vi->Db); CHKERRQ(ierr); 1489 ierr = VecDestroy(&vi->z); CHKERRQ(ierr); 1490 ierr = VecDestroy(&vi->t); CHKERRQ(ierr); 1491 } 1492 1493 if (!vi->usersetxbounds) { 1494 ierr = VecDestroy(&vi->xl); CHKERRQ(ierr); 1495 ierr = VecDestroy(&vi->xu); CHKERRQ(ierr); 1496 } 1497 1498 ierr = PetscViewerASCIIMonitorDestroy(&vi->lsmonitor);CHKERRQ(ierr); 1499 ierr = PetscFree(snes->data);CHKERRQ(ierr); 1500 1501 /* clear composed functions */ 1502 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSet_C","",PETSC_NULL);CHKERRQ(ierr); 1503 ierr = PetscObjectComposeFunctionDynamic((PetscObject)snes,"SNESLineSearchSetMonitor_C","",PETSC_NULL);CHKERRQ(ierr); 1504 PetscFunctionReturn(0); 1505 } 1506 1507 /* -------------------------------------------------------------------------- */ 1508 #undef __FUNCT__ 1509 #define __FUNCT__ "SNESLineSearchNo_VI" 1510 1511 /* 1512 This routine does not actually do a line search but it takes a full newton 1513 step while ensuring that the new iterates remain within the constraints. 1514 1515 */ 1516 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) 1517 { 1518 PetscErrorCode ierr; 1519 SNES_VI *vi = (SNES_VI*)snes->data; 1520 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1521 1522 PetscFunctionBegin; 1523 *flag = PETSC_TRUE; 1524 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1525 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); /* ynorm = || y || */ 1526 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1527 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1528 if (vi->postcheckstep) { 1529 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1530 } 1531 if (changed_y) { 1532 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1533 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1534 } 1535 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1536 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1537 if (!snes->domainerror) { 1538 if (snes->ops->solve != SNESSolveVI_SS) { 1539 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1540 } else { 1541 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); /* gnorm = || g || */ 1542 } 1543 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1544 } 1545 if (vi->lsmonitor) { 1546 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1547 } 1548 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1549 PetscFunctionReturn(0); 1550 } 1551 1552 /* -------------------------------------------------------------------------- */ 1553 #undef __FUNCT__ 1554 #define __FUNCT__ "SNESLineSearchNoNorms_VI" 1555 1556 /* 1557 This routine is a copy of SNESLineSearchNoNorms in snes/impls/ls/ls.c 1558 */ 1559 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) 1560 { 1561 PetscErrorCode ierr; 1562 SNES_VI *vi = (SNES_VI*)snes->data; 1563 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1564 1565 PetscFunctionBegin; 1566 *flag = PETSC_TRUE; 1567 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1568 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1569 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1570 if (vi->postcheckstep) { 1571 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1572 } 1573 if (changed_y) { 1574 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); /* w <- x - y */ 1575 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1576 } 1577 1578 /* don't evaluate function the last time through */ 1579 if (snes->iter < snes->max_its-1) { 1580 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1581 } 1582 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1583 PetscFunctionReturn(0); 1584 } 1585 1586 /* -------------------------------------------------------------------------- */ 1587 #undef __FUNCT__ 1588 #define __FUNCT__ "SNESLineSearchCubic_VI" 1589 /* 1590 This routine implements a cubic line search while doing a projection on the variable bounds 1591 */ 1592 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) 1593 { 1594 PetscReal initslope,lambdaprev,gnormprev,a,b,d,t1,t2,rellength; 1595 PetscReal minlambda,lambda,lambdatemp; 1596 #if defined(PETSC_USE_COMPLEX) 1597 PetscScalar cinitslope; 1598 #endif 1599 PetscErrorCode ierr; 1600 PetscInt count; 1601 SNES_VI *vi = (SNES_VI*)snes->data; 1602 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1603 MPI_Comm comm; 1604 1605 PetscFunctionBegin; 1606 ierr = PetscObjectGetComm((PetscObject)snes,&comm);CHKERRQ(ierr); 1607 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1608 *flag = PETSC_TRUE; 1609 1610 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); 1611 if (*ynorm == 0.0) { 1612 if (vi->lsmonitor) { 1613 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Initial direction and size is 0\n");CHKERRQ(ierr); 1614 } 1615 *gnorm = fnorm; 1616 ierr = VecCopy(x,w);CHKERRQ(ierr); 1617 ierr = VecCopy(f,g);CHKERRQ(ierr); 1618 *flag = PETSC_FALSE; 1619 goto theend1; 1620 } 1621 if (*ynorm > vi->maxstep) { /* Step too big, so scale back */ 1622 if (vi->lsmonitor) { 1623 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Scaling step by %G old ynorm %G\n",vi->maxstep/(*ynorm),*ynorm);CHKERRQ(ierr); 1624 } 1625 ierr = VecScale(y,vi->maxstep/(*ynorm));CHKERRQ(ierr); 1626 *ynorm = vi->maxstep; 1627 } 1628 ierr = VecMaxPointwiseDivide(y,x,&rellength);CHKERRQ(ierr); 1629 minlambda = vi->minlambda/rellength; 1630 ierr = MatMult(snes->jacobian,y,w);CHKERRQ(ierr); 1631 #if defined(PETSC_USE_COMPLEX) 1632 ierr = VecDot(f,w,&cinitslope);CHKERRQ(ierr); 1633 initslope = PetscRealPart(cinitslope); 1634 #else 1635 ierr = VecDot(f,w,&initslope);CHKERRQ(ierr); 1636 #endif 1637 if (initslope > 0.0) initslope = -initslope; 1638 if (initslope == 0.0) initslope = -1.0; 1639 1640 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1641 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1642 if (snes->nfuncs >= snes->max_funcs) { 1643 ierr = PetscInfo(snes,"Exceeded maximum function evaluations, while checking full step length!\n");CHKERRQ(ierr); 1644 *flag = PETSC_FALSE; 1645 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1646 goto theend1; 1647 } 1648 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1649 if (snes->ops->solve != SNESSolveVI_SS) { 1650 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1651 } else { 1652 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1653 } 1654 if (snes->domainerror) { 1655 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1656 PetscFunctionReturn(0); 1657 } 1658 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1659 ierr = PetscInfo2(snes,"Initial fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1660 if (.5*(*gnorm)*(*gnorm) <= .5*fnorm*fnorm + vi->alpha*initslope) { /* Sufficient reduction */ 1661 if (vi->lsmonitor) { 1662 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1663 } 1664 goto theend1; 1665 } 1666 1667 /* Fit points with quadratic */ 1668 lambda = 1.0; 1669 lambdatemp = -initslope/((*gnorm)*(*gnorm) - fnorm*fnorm - 2.0*initslope); 1670 lambdaprev = lambda; 1671 gnormprev = *gnorm; 1672 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 1673 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 1674 else lambda = lambdatemp; 1675 1676 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 1677 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1678 if (snes->nfuncs >= snes->max_funcs) { 1679 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while attempting quadratic backtracking! %D \n",snes->nfuncs);CHKERRQ(ierr); 1680 *flag = PETSC_FALSE; 1681 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1682 goto theend1; 1683 } 1684 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1685 if (snes->ops->solve != SNESSolveVI_SS) { 1686 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1687 } else { 1688 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1689 } 1690 if (snes->domainerror) { 1691 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1692 PetscFunctionReturn(0); 1693 } 1694 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1695 if (vi->lsmonitor) { 1696 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: gnorm after quadratic fit %G\n",*gnorm);CHKERRQ(ierr); 1697 } 1698 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* sufficient reduction */ 1699 if (vi->lsmonitor) { 1700 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Quadratically determined step, lambda=%18.16e\n",lambda);CHKERRQ(ierr); 1701 } 1702 goto theend1; 1703 } 1704 1705 /* Fit points with cubic */ 1706 count = 1; 1707 while (PETSC_TRUE) { 1708 if (lambda <= minlambda) { 1709 if (vi->lsmonitor) { 1710 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: unable to find good step length! After %D tries \n",count);CHKERRQ(ierr); 1711 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); 1712 } 1713 *flag = PETSC_FALSE; 1714 break; 1715 } 1716 t1 = .5*((*gnorm)*(*gnorm) - fnorm*fnorm) - lambda*initslope; 1717 t2 = .5*(gnormprev*gnormprev - fnorm*fnorm) - lambdaprev*initslope; 1718 a = (t1/(lambda*lambda) - t2/(lambdaprev*lambdaprev))/(lambda-lambdaprev); 1719 b = (-lambdaprev*t1/(lambda*lambda) + lambda*t2/(lambdaprev*lambdaprev))/(lambda-lambdaprev); 1720 d = b*b - 3*a*initslope; 1721 if (d < 0.0) d = 0.0; 1722 if (a == 0.0) { 1723 lambdatemp = -initslope/(2.0*b); 1724 } else { 1725 lambdatemp = (-b + sqrt(d))/(3.0*a); 1726 } 1727 lambdaprev = lambda; 1728 gnormprev = *gnorm; 1729 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 1730 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 1731 else lambda = lambdatemp; 1732 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 1733 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1734 if (snes->nfuncs >= snes->max_funcs) { 1735 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while looking for good step length! %D \n",count);CHKERRQ(ierr); 1736 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); 1737 *flag = PETSC_FALSE; 1738 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1739 break; 1740 } 1741 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1742 if (snes->ops->solve != SNESSolveVI_SS) { 1743 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1744 } else { 1745 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1746 } 1747 if (snes->domainerror) { 1748 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1749 PetscFunctionReturn(0); 1750 } 1751 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1752 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* is reduction enough? */ 1753 if (vi->lsmonitor) { 1754 ierr = PetscPrintf(comm," Line search: Cubically determined step, current gnorm %G lambda=%18.16e\n",*gnorm,lambda);CHKERRQ(ierr); 1755 } 1756 break; 1757 } else { 1758 if (vi->lsmonitor) { 1759 ierr = PetscPrintf(comm," Line search: Cubic step no good, shrinking lambda, current gnorm %G lambda=%18.16e\n",*gnorm,lambda);CHKERRQ(ierr); 1760 } 1761 } 1762 count++; 1763 } 1764 theend1: 1765 /* Optional user-defined check for line search step validity */ 1766 if (vi->postcheckstep && *flag) { 1767 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1768 if (changed_y) { 1769 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1770 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1771 } 1772 if (changed_y || changed_w) { /* recompute the function if the step has changed */ 1773 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1774 if (snes->ops->solve != SNESSolveVI_SS) { 1775 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1776 } else { 1777 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1778 } 1779 if (snes->domainerror) { 1780 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1781 PetscFunctionReturn(0); 1782 } 1783 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1784 ierr = VecNormBegin(y,NORM_2,ynorm);CHKERRQ(ierr); 1785 ierr = VecNormEnd(y,NORM_2,ynorm);CHKERRQ(ierr); 1786 } 1787 } 1788 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1789 PetscFunctionReturn(0); 1790 } 1791 1792 #undef __FUNCT__ 1793 #define __FUNCT__ "SNESLineSearchQuadratic_VI" 1794 /* 1795 This routine does a quadratic line search while keeping the iterates within the variable bounds 1796 */ 1797 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) 1798 { 1799 /* 1800 Note that for line search purposes we work with with the related 1801 minimization problem: 1802 min z(x): R^n -> R, 1803 where z(x) = .5 * fnorm*fnorm,and fnorm = || f ||_2. 1804 */ 1805 PetscReal initslope,minlambda,lambda,lambdatemp,rellength; 1806 #if defined(PETSC_USE_COMPLEX) 1807 PetscScalar cinitslope; 1808 #endif 1809 PetscErrorCode ierr; 1810 PetscInt count; 1811 SNES_VI *vi = (SNES_VI*)snes->data; 1812 PetscBool changed_w = PETSC_FALSE,changed_y = PETSC_FALSE; 1813 1814 PetscFunctionBegin; 1815 ierr = PetscLogEventBegin(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1816 *flag = PETSC_TRUE; 1817 1818 ierr = VecNorm(y,NORM_2,ynorm);CHKERRQ(ierr); 1819 if (*ynorm == 0.0) { 1820 if (vi->lsmonitor) { 1821 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor,"Line search: Direction and size is 0\n");CHKERRQ(ierr); 1822 } 1823 *gnorm = fnorm; 1824 ierr = VecCopy(x,w);CHKERRQ(ierr); 1825 ierr = VecCopy(f,g);CHKERRQ(ierr); 1826 *flag = PETSC_FALSE; 1827 goto theend2; 1828 } 1829 if (*ynorm > vi->maxstep) { /* Step too big, so scale back */ 1830 ierr = VecScale(y,vi->maxstep/(*ynorm));CHKERRQ(ierr); 1831 *ynorm = vi->maxstep; 1832 } 1833 ierr = VecMaxPointwiseDivide(y,x,&rellength);CHKERRQ(ierr); 1834 minlambda = vi->minlambda/rellength; 1835 ierr = MatMult(snes->jacobian,y,w);CHKERRQ(ierr); 1836 #if defined(PETSC_USE_COMPLEX) 1837 ierr = VecDot(f,w,&cinitslope);CHKERRQ(ierr); 1838 initslope = PetscRealPart(cinitslope); 1839 #else 1840 ierr = VecDot(f,w,&initslope);CHKERRQ(ierr); 1841 #endif 1842 if (initslope > 0.0) initslope = -initslope; 1843 if (initslope == 0.0) initslope = -1.0; 1844 ierr = PetscInfo1(snes,"Initslope %G \n",initslope);CHKERRQ(ierr); 1845 1846 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1847 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1848 if (snes->nfuncs >= snes->max_funcs) { 1849 ierr = PetscInfo(snes,"Exceeded maximum function evaluations, while checking full step length!\n");CHKERRQ(ierr); 1850 *flag = PETSC_FALSE; 1851 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1852 goto theend2; 1853 } 1854 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1855 if (snes->ops->solve != SNESSolveVI_SS) { 1856 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1857 } else { 1858 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1859 } 1860 if (snes->domainerror) { 1861 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1862 PetscFunctionReturn(0); 1863 } 1864 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1865 if (.5*(*gnorm)*(*gnorm) <= .5*fnorm*fnorm + vi->alpha*initslope) { /* Sufficient reduction */ 1866 if (vi->lsmonitor) { 1867 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line search: Using full step: fnorm %G gnorm %G\n",fnorm,*gnorm);CHKERRQ(ierr); 1868 } 1869 goto theend2; 1870 } 1871 1872 /* Fit points with quadratic */ 1873 lambda = 1.0; 1874 count = 1; 1875 while (PETSC_TRUE) { 1876 if (lambda <= minlambda) { /* bad luck; use full step */ 1877 if (vi->lsmonitor) { 1878 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor,"Line search: Unable to find good step length! %D \n",count);CHKERRQ(ierr); 1879 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); 1880 } 1881 ierr = VecCopy(x,w);CHKERRQ(ierr); 1882 *flag = PETSC_FALSE; 1883 break; 1884 } 1885 lambdatemp = -initslope/((*gnorm)*(*gnorm) - fnorm*fnorm - 2.0*initslope); 1886 if (lambdatemp > .5*lambda) lambdatemp = .5*lambda; 1887 if (lambdatemp <= .1*lambda) lambda = .1*lambda; 1888 else lambda = lambdatemp; 1889 1890 ierr = VecWAXPY(w,-lambda,y,x);CHKERRQ(ierr); 1891 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1892 if (snes->nfuncs >= snes->max_funcs) { 1893 ierr = PetscInfo1(snes,"Exceeded maximum function evaluations, while looking for good step length! %D \n",count);CHKERRQ(ierr); 1894 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); 1895 *flag = PETSC_FALSE; 1896 snes->reason = SNES_DIVERGED_FUNCTION_COUNT; 1897 break; 1898 } 1899 ierr = SNESComputeFunction(snes,w,g);CHKERRQ(ierr); 1900 if (snes->domainerror) { 1901 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1902 PetscFunctionReturn(0); 1903 } 1904 if (snes->ops->solve != SNESSolveVI_SS) { 1905 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1906 } else { 1907 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1908 } 1909 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1910 if (.5*(*gnorm)*(*gnorm) < .5*fnorm*fnorm + lambda*vi->alpha*initslope) { /* sufficient reduction */ 1911 if (vi->lsmonitor) { 1912 ierr = PetscViewerASCIIMonitorPrintf(vi->lsmonitor," Line Search: Quadratically determined step, lambda=%G\n",lambda);CHKERRQ(ierr); 1913 } 1914 break; 1915 } 1916 count++; 1917 } 1918 theend2: 1919 /* Optional user-defined check for line search step validity */ 1920 if (vi->postcheckstep) { 1921 ierr = (*vi->postcheckstep)(snes,x,y,w,vi->postcheck,&changed_y,&changed_w);CHKERRQ(ierr); 1922 if (changed_y) { 1923 ierr = VecWAXPY(w,-1.0,y,x);CHKERRQ(ierr); 1924 ierr = SNESVIProjectOntoBounds(snes,w);CHKERRQ(ierr); 1925 } 1926 if (changed_y || changed_w) { /* recompute the function if the step has changed */ 1927 ierr = SNESComputeFunction(snes,w,g); 1928 if (snes->domainerror) { 1929 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1930 PetscFunctionReturn(0); 1931 } 1932 if (snes->ops->solve != SNESSolveVI_SS) { 1933 ierr = SNESVIComputeInactiveSetFnorm(snes,g,w,gnorm);CHKERRQ(ierr); 1934 } else { 1935 ierr = VecNorm(g,NORM_2,gnorm);CHKERRQ(ierr); 1936 } 1937 1938 ierr = VecNormBegin(y,NORM_2,ynorm);CHKERRQ(ierr); 1939 ierr = VecNormEnd(y,NORM_2,ynorm);CHKERRQ(ierr); 1940 if (PetscIsInfOrNanReal(*gnorm)) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FP,"User provided compute function generated a Not-a-Number"); 1941 } 1942 } 1943 ierr = PetscLogEventEnd(SNES_LineSearch,snes,x,f,g);CHKERRQ(ierr); 1944 PetscFunctionReturn(0); 1945 } 1946 1947 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*/ 1948 /* -------------------------------------------------------------------------- */ 1949 EXTERN_C_BEGIN 1950 #undef __FUNCT__ 1951 #define __FUNCT__ "SNESLineSearchSet_VI" 1952 PetscErrorCode SNESLineSearchSet_VI(SNES snes,FCN2 func,void *lsctx) 1953 { 1954 PetscFunctionBegin; 1955 ((SNES_VI *)(snes->data))->LineSearch = func; 1956 ((SNES_VI *)(snes->data))->lsP = lsctx; 1957 PetscFunctionReturn(0); 1958 } 1959 EXTERN_C_END 1960 1961 /* -------------------------------------------------------------------------- */ 1962 EXTERN_C_BEGIN 1963 #undef __FUNCT__ 1964 #define __FUNCT__ "SNESLineSearchSetMonitor_VI" 1965 PetscErrorCode SNESLineSearchSetMonitor_VI(SNES snes,PetscBool flg) 1966 { 1967 SNES_VI *vi = (SNES_VI*)snes->data; 1968 PetscErrorCode ierr; 1969 1970 PetscFunctionBegin; 1971 if (flg && !vi->lsmonitor) { 1972 ierr = PetscViewerASCIIMonitorCreate(((PetscObject)snes)->comm,"stdout",((PetscObject)snes)->tablevel,&vi->lsmonitor);CHKERRQ(ierr); 1973 } else if (!flg && vi->lsmonitor) { 1974 ierr = PetscViewerASCIIMonitorDestroy(&vi->lsmonitor);CHKERRQ(ierr); 1975 } 1976 PetscFunctionReturn(0); 1977 } 1978 EXTERN_C_END 1979 1980 /* 1981 SNESView_VI - Prints info from the SNESVI data structure. 1982 1983 Input Parameters: 1984 . SNES - the SNES context 1985 . viewer - visualization context 1986 1987 Application Interface Routine: SNESView() 1988 */ 1989 #undef __FUNCT__ 1990 #define __FUNCT__ "SNESView_VI" 1991 static PetscErrorCode SNESView_VI(SNES snes,PetscViewer viewer) 1992 { 1993 SNES_VI *vi = (SNES_VI *)snes->data; 1994 const char *cstr,*tstr; 1995 PetscErrorCode ierr; 1996 PetscBool iascii; 1997 1998 PetscFunctionBegin; 1999 ierr = PetscTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr); 2000 if (iascii) { 2001 if (vi->LineSearch == SNESLineSearchNo_VI) cstr = "SNESLineSearchNo"; 2002 else if (vi->LineSearch == SNESLineSearchQuadratic_VI) cstr = "SNESLineSearchQuadratic"; 2003 else if (vi->LineSearch == SNESLineSearchCubic_VI) cstr = "SNESLineSearchCubic"; 2004 else cstr = "unknown"; 2005 if (snes->ops->solve == SNESSolveVI_SS) tstr = "Semismooth"; 2006 else if (snes->ops->solve == SNESSolveVI_RS) tstr = "Reduced Space"; 2007 else if (snes->ops->solve == SNESSolveVI_RS2) tstr = "Augmented Space"; 2008 else tstr = "unknown"; 2009 ierr = PetscViewerASCIIPrintf(viewer," VI algorithm: %s\n",tstr);CHKERRQ(ierr); 2010 ierr = PetscViewerASCIIPrintf(viewer," line search variant: %s\n",cstr);CHKERRQ(ierr); 2011 ierr = PetscViewerASCIIPrintf(viewer," alpha=%G, maxstep=%G, minlambda=%G\n",vi->alpha,vi->maxstep,vi->minlambda);CHKERRQ(ierr); 2012 } else { 2013 SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Viewer type %s not supported for SNES EQ VI",((PetscObject)viewer)->type_name); 2014 } 2015 PetscFunctionReturn(0); 2016 } 2017 2018 #undef __FUNCT__ 2019 #define __FUNCT__ "SNESVISetVariableBounds" 2020 /*@ 2021 SNESVISetVariableBounds - Sets the lower and upper bounds for the solution vector. xl <= x <= xu. 2022 2023 Input Parameters: 2024 . snes - the SNES context. 2025 . xl - lower bound. 2026 . xu - upper bound. 2027 2028 Notes: 2029 If this routine is not called then the lower and upper bounds are set to 2030 SNES_VI_INF and SNES_VI_NINF respectively during SNESSetUp(). 2031 2032 @*/ 2033 PetscErrorCode SNESVISetVariableBounds(SNES snes, Vec xl, Vec xu) 2034 { 2035 SNES_VI *vi; 2036 PetscErrorCode ierr; 2037 2038 PetscFunctionBegin; 2039 PetscValidHeaderSpecific(snes,SNES_CLASSID,1); 2040 PetscValidHeaderSpecific(xl,VEC_CLASSID,2); 2041 PetscValidHeaderSpecific(xu,VEC_CLASSID,3); 2042 if (!snes->vec_func) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call SNESSetFunction() first"); 2043 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); 2044 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); 2045 ierr = SNESSetType(snes,SNESVI);CHKERRQ(ierr); 2046 vi = (SNES_VI*)snes->data; 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_RS; 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