1 2 static char help[] = "Tests recovery from domain errors in MatMult() and PCApply()\n\n"; 3 4 /* 5 See src/ksp/ksp/tutorials/ex19.c from which this was copied 6 */ 7 8 #include <petscsnes.h> 9 #include <petscdm.h> 10 #include <petscdmda.h> 11 12 /* 13 User-defined routines and data structures 14 */ 15 typedef struct { 16 PetscScalar u, v, omega, temp; 17 } Field; 18 19 PetscErrorCode FormFunctionLocal(DMDALocalInfo *, Field **, Field **, void *); 20 21 typedef struct { 22 PetscReal lidvelocity, prandtl, grashof; /* physical parameters */ 23 PetscBool draw_contours; /* flag - 1 indicates drawing contours */ 24 PetscBool errorindomain; 25 PetscBool errorindomainmf; 26 SNES snes; 27 } AppCtx; 28 29 typedef struct { 30 Mat Jmf; 31 } MatShellCtx; 32 33 extern PetscErrorCode FormInitialGuess(AppCtx *, DM, Vec); 34 extern PetscErrorCode MatMult_MyShell(Mat, Vec, Vec); 35 extern PetscErrorCode MatAssemblyEnd_MyShell(Mat, MatAssemblyType); 36 extern PetscErrorCode PCApply_MyShell(PC, Vec, Vec); 37 extern PetscErrorCode SNESComputeJacobian_MyShell(SNES, Vec, Mat, Mat, void *); 38 39 int main(int argc, char **argv) { 40 AppCtx user; /* user-defined work context */ 41 PetscInt mx, my; 42 MPI_Comm comm; 43 DM da; 44 Vec x; 45 Mat J = NULL, Jmf = NULL; 46 MatShellCtx matshellctx; 47 PetscInt mlocal, nlocal; 48 PC pc; 49 KSP ksp; 50 PetscBool errorinmatmult = PETSC_FALSE, errorinpcapply = PETSC_FALSE, errorinpcsetup = PETSC_FALSE; 51 52 PetscFunctionBeginUser; 53 PetscCall(PetscInitialize(&argc, &argv, (char *)0, help)); 54 PetscCall(PetscOptionsGetBool(NULL, NULL, "-error_in_matmult", &errorinmatmult, NULL)); 55 PetscCall(PetscOptionsGetBool(NULL, NULL, "-error_in_pcapply", &errorinpcapply, NULL)); 56 PetscCall(PetscOptionsGetBool(NULL, NULL, "-error_in_pcsetup", &errorinpcsetup, NULL)); 57 user.errorindomain = PETSC_FALSE; 58 PetscCall(PetscOptionsGetBool(NULL, NULL, "-error_in_domain", &user.errorindomain, NULL)); 59 user.errorindomainmf = PETSC_FALSE; 60 PetscCall(PetscOptionsGetBool(NULL, NULL, "-error_in_domainmf", &user.errorindomainmf, NULL)); 61 62 comm = PETSC_COMM_WORLD; 63 PetscCall(SNESCreate(comm, &user.snes)); 64 65 /* 66 Create distributed array object to manage parallel grid and vectors 67 for principal unknowns (x) and governing residuals (f) 68 */ 69 PetscCall(DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DMDA_STENCIL_STAR, 4, 4, PETSC_DECIDE, PETSC_DECIDE, 4, 1, 0, 0, &da)); 70 PetscCall(DMSetFromOptions(da)); 71 PetscCall(DMSetUp(da)); 72 PetscCall(SNESSetDM(user.snes, da)); 73 74 PetscCall(DMDAGetInfo(da, 0, &mx, &my, PETSC_IGNORE, PETSC_IGNORE, PETSC_IGNORE, PETSC_IGNORE, PETSC_IGNORE, PETSC_IGNORE, PETSC_IGNORE, PETSC_IGNORE, PETSC_IGNORE, PETSC_IGNORE)); 75 /* 76 Problem parameters (velocity of lid, prandtl, and grashof numbers) 77 */ 78 user.lidvelocity = 1.0 / (mx * my); 79 user.prandtl = 1.0; 80 user.grashof = 1.0; 81 82 PetscCall(PetscOptionsGetReal(NULL, NULL, "-lidvelocity", &user.lidvelocity, NULL)); 83 PetscCall(PetscOptionsGetReal(NULL, NULL, "-prandtl", &user.prandtl, NULL)); 84 PetscCall(PetscOptionsGetReal(NULL, NULL, "-grashof", &user.grashof, NULL)); 85 PetscCall(PetscOptionsHasName(NULL, NULL, "-contours", &user.draw_contours)); 86 87 PetscCall(DMDASetFieldName(da, 0, "x_velocity")); 88 PetscCall(DMDASetFieldName(da, 1, "y_velocity")); 89 PetscCall(DMDASetFieldName(da, 2, "Omega")); 90 PetscCall(DMDASetFieldName(da, 3, "temperature")); 91 92 /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 93 Create user context, set problem data, create vector data structures. 94 Also, compute the initial guess. 95 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 96 97 /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 98 Create nonlinear solver context 99 100 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 101 PetscCall(DMSetApplicationContext(da, &user)); 102 PetscCall(DMDASNESSetFunctionLocal(da, INSERT_VALUES, (PetscErrorCode(*)(DMDALocalInfo *, void *, void *, void *))FormFunctionLocal, &user)); 103 104 if (errorinmatmult) { 105 PetscCall(MatCreateSNESMF(user.snes, &Jmf)); 106 PetscCall(MatSetFromOptions(Jmf)); 107 PetscCall(MatGetLocalSize(Jmf, &mlocal, &nlocal)); 108 matshellctx.Jmf = Jmf; 109 PetscCall(MatCreateShell(PetscObjectComm((PetscObject)Jmf), mlocal, nlocal, PETSC_DECIDE, PETSC_DECIDE, &matshellctx, &J)); 110 PetscCall(MatShellSetOperation(J, MATOP_MULT, (void (*)(void))MatMult_MyShell)); 111 PetscCall(MatShellSetOperation(J, MATOP_ASSEMBLY_END, (void (*)(void))MatAssemblyEnd_MyShell)); 112 PetscCall(SNESSetJacobian(user.snes, J, J, MatMFFDComputeJacobian, NULL)); 113 } 114 115 PetscCall(SNESSetFromOptions(user.snes)); 116 PetscCall(PetscPrintf(comm, "lid velocity = %g, prandtl # = %g, grashof # = %g\n", (double)user.lidvelocity, (double)user.prandtl, (double)user.grashof)); 117 118 if (errorinpcapply) { 119 PetscCall(SNESGetKSP(user.snes, &ksp)); 120 PetscCall(KSPGetPC(ksp, &pc)); 121 PetscCall(PCSetType(pc, PCSHELL)); 122 PetscCall(PCShellSetApply(pc, PCApply_MyShell)); 123 } 124 125 /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 126 Solve the nonlinear system 127 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 128 PetscCall(DMCreateGlobalVector(da, &x)); 129 PetscCall(FormInitialGuess(&user, da, x)); 130 131 if (errorinpcsetup) { 132 PetscCall(SNESSetUp(user.snes)); 133 PetscCall(SNESSetJacobian(user.snes, NULL, NULL, SNESComputeJacobian_MyShell, NULL)); 134 } 135 PetscCall(SNESSolve(user.snes, NULL, x)); 136 137 /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 138 Free work space. All PETSc objects should be destroyed when they 139 are no longer needed. 140 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 141 PetscCall(MatDestroy(&J)); 142 PetscCall(MatDestroy(&Jmf)); 143 PetscCall(VecDestroy(&x)); 144 PetscCall(DMDestroy(&da)); 145 PetscCall(SNESDestroy(&user.snes)); 146 PetscCall(PetscFinalize()); 147 return 0; 148 } 149 150 /* ------------------------------------------------------------------- */ 151 152 /* 153 FormInitialGuess - Forms initial approximation. 154 155 Input Parameters: 156 user - user-defined application context 157 X - vector 158 159 Output Parameter: 160 X - vector 161 */ 162 PetscErrorCode FormInitialGuess(AppCtx *user, DM da, Vec X) { 163 PetscInt i, j, mx, xs, ys, xm, ym; 164 PetscReal grashof, dx; 165 Field **x; 166 167 PetscFunctionBeginUser; 168 grashof = user->grashof; 169 170 PetscCall(DMDAGetInfo(da, 0, &mx, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0)); 171 dx = 1.0 / (mx - 1); 172 173 /* 174 Get local grid boundaries (for 2-dimensional DMDA): 175 xs, ys - starting grid indices (no ghost points) 176 xm, ym - widths of local grid (no ghost points) 177 */ 178 PetscCall(DMDAGetCorners(da, &xs, &ys, NULL, &xm, &ym, NULL)); 179 180 /* 181 Get a pointer to vector data. 182 - For default PETSc vectors, VecGetArray() returns a pointer to 183 the data array. Otherwise, the routine is implementation dependent. 184 - You MUST call VecRestoreArray() when you no longer need access to 185 the array. 186 */ 187 PetscCall(DMDAVecGetArray(da, X, &x)); 188 189 /* 190 Compute initial guess over the locally owned part of the grid 191 Initial condition is motionless fluid and equilibrium temperature 192 */ 193 for (j = ys; j < ys + ym; j++) { 194 for (i = xs; i < xs + xm; i++) { 195 x[j][i].u = 0.0; 196 x[j][i].v = 0.0; 197 x[j][i].omega = 0.0; 198 x[j][i].temp = (grashof > 0) * i * dx; 199 } 200 } 201 202 /* 203 Restore vector 204 */ 205 PetscCall(DMDAVecRestoreArray(da, X, &x)); 206 PetscFunctionReturn(0); 207 } 208 209 PetscErrorCode FormFunctionLocal(DMDALocalInfo *info, Field **x, Field **f, void *ptr) { 210 AppCtx *user = (AppCtx *)ptr; 211 PetscInt xints, xinte, yints, yinte, i, j; 212 PetscReal hx, hy, dhx, dhy, hxdhy, hydhx; 213 PetscReal grashof, prandtl, lid; 214 PetscScalar u, uxx, uyy, vx, vy, avx, avy, vxp, vxm, vyp, vym; 215 static PetscInt fail = 0; 216 217 PetscFunctionBeginUser; 218 if ((fail++ > 7 && user->errorindomainmf) || (fail++ > 36 && user->errorindomain)) { 219 PetscMPIInt rank; 220 PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)user->snes), &rank)); 221 if (rank == 0) { PetscCall(SNESSetFunctionDomainError(user->snes)); } 222 } 223 grashof = user->grashof; 224 prandtl = user->prandtl; 225 lid = user->lidvelocity; 226 227 /* 228 Define mesh intervals ratios for uniform grid. 229 230 Note: FD formulae below are normalized by multiplying through by 231 local volume element (i.e. hx*hy) to obtain coefficients O(1) in two dimensions. 232 233 */ 234 dhx = (PetscReal)(info->mx - 1); 235 dhy = (PetscReal)(info->my - 1); 236 hx = 1.0 / dhx; 237 hy = 1.0 / dhy; 238 hxdhy = hx * dhy; 239 hydhx = hy * dhx; 240 241 xints = info->xs; 242 xinte = info->xs + info->xm; 243 yints = info->ys; 244 yinte = info->ys + info->ym; 245 246 /* Test whether we are on the bottom edge of the global array */ 247 if (yints == 0) { 248 j = 0; 249 yints = yints + 1; 250 /* bottom edge */ 251 for (i = info->xs; i < info->xs + info->xm; i++) { 252 f[j][i].u = x[j][i].u; 253 f[j][i].v = x[j][i].v; 254 f[j][i].omega = x[j][i].omega + (x[j + 1][i].u - x[j][i].u) * dhy; 255 f[j][i].temp = x[j][i].temp - x[j + 1][i].temp; 256 } 257 } 258 259 /* Test whether we are on the top edge of the global array */ 260 if (yinte == info->my) { 261 j = info->my - 1; 262 yinte = yinte - 1; 263 /* top edge */ 264 for (i = info->xs; i < info->xs + info->xm; i++) { 265 f[j][i].u = x[j][i].u - lid; 266 f[j][i].v = x[j][i].v; 267 f[j][i].omega = x[j][i].omega + (x[j][i].u - x[j - 1][i].u) * dhy; 268 f[j][i].temp = x[j][i].temp - x[j - 1][i].temp; 269 } 270 } 271 272 /* Test whether we are on the left edge of the global array */ 273 if (xints == 0) { 274 i = 0; 275 xints = xints + 1; 276 /* left edge */ 277 for (j = info->ys; j < info->ys + info->ym; j++) { 278 f[j][i].u = x[j][i].u; 279 f[j][i].v = x[j][i].v; 280 f[j][i].omega = x[j][i].omega - (x[j][i + 1].v - x[j][i].v) * dhx; 281 f[j][i].temp = x[j][i].temp; 282 } 283 } 284 285 /* Test whether we are on the right edge of the global array */ 286 if (xinte == info->mx) { 287 i = info->mx - 1; 288 xinte = xinte - 1; 289 /* right edge */ 290 for (j = info->ys; j < info->ys + info->ym; j++) { 291 f[j][i].u = x[j][i].u; 292 f[j][i].v = x[j][i].v; 293 f[j][i].omega = x[j][i].omega - (x[j][i].v - x[j][i - 1].v) * dhx; 294 f[j][i].temp = x[j][i].temp - (PetscReal)(grashof > 0); 295 } 296 } 297 298 /* Compute over the interior points */ 299 for (j = yints; j < yinte; j++) { 300 for (i = xints; i < xinte; i++) { 301 /* 302 convective coefficients for upwinding 303 */ 304 vx = x[j][i].u; 305 avx = PetscAbsScalar(vx); 306 vxp = .5 * (vx + avx); 307 vxm = .5 * (vx - avx); 308 vy = x[j][i].v; 309 avy = PetscAbsScalar(vy); 310 vyp = .5 * (vy + avy); 311 vym = .5 * (vy - avy); 312 313 /* U velocity */ 314 u = x[j][i].u; 315 uxx = (2.0 * u - x[j][i - 1].u - x[j][i + 1].u) * hydhx; 316 uyy = (2.0 * u - x[j - 1][i].u - x[j + 1][i].u) * hxdhy; 317 f[j][i].u = uxx + uyy - .5 * (x[j + 1][i].omega - x[j - 1][i].omega) * hx; 318 319 /* V velocity */ 320 u = x[j][i].v; 321 uxx = (2.0 * u - x[j][i - 1].v - x[j][i + 1].v) * hydhx; 322 uyy = (2.0 * u - x[j - 1][i].v - x[j + 1][i].v) * hxdhy; 323 f[j][i].v = uxx + uyy + .5 * (x[j][i + 1].omega - x[j][i - 1].omega) * hy; 324 325 /* Omega */ 326 u = x[j][i].omega; 327 uxx = (2.0 * u - x[j][i - 1].omega - x[j][i + 1].omega) * hydhx; 328 uyy = (2.0 * u - x[j - 1][i].omega - x[j + 1][i].omega) * hxdhy; 329 f[j][i].omega = uxx + uyy + (vxp * (u - x[j][i - 1].omega) + vxm * (x[j][i + 1].omega - u)) * hy + (vyp * (u - x[j - 1][i].omega) + vym * (x[j + 1][i].omega - u)) * hx - .5 * grashof * (x[j][i + 1].temp - x[j][i - 1].temp) * hy; 330 331 /* Temperature */ 332 u = x[j][i].temp; 333 uxx = (2.0 * u - x[j][i - 1].temp - x[j][i + 1].temp) * hydhx; 334 uyy = (2.0 * u - x[j - 1][i].temp - x[j + 1][i].temp) * hxdhy; 335 f[j][i].temp = uxx + uyy + prandtl * ((vxp * (u - x[j][i - 1].temp) + vxm * (x[j][i + 1].temp - u)) * hy + (vyp * (u - x[j - 1][i].temp) + vym * (x[j + 1][i].temp - u)) * hx); 336 } 337 } 338 339 /* 340 Flop count (multiply-adds are counted as 2 operations) 341 */ 342 PetscCall(PetscLogFlops(84.0 * info->ym * info->xm)); 343 PetscFunctionReturn(0); 344 } 345 346 PetscErrorCode MatMult_MyShell(Mat A, Vec x, Vec y) { 347 MatShellCtx *matshellctx; 348 static PetscInt fail = 0; 349 350 PetscFunctionBegin; 351 PetscCall(MatShellGetContext(A, &matshellctx)); 352 PetscCall(MatMult(matshellctx->Jmf, x, y)); 353 if (fail++ > 5) { 354 PetscMPIInt rank; 355 PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)A), &rank)); 356 if (rank == 0) PetscCall(VecSetInf(y)); 357 } 358 PetscFunctionReturn(0); 359 } 360 361 PetscErrorCode MatAssemblyEnd_MyShell(Mat A, MatAssemblyType tp) { 362 MatShellCtx *matshellctx; 363 364 PetscFunctionBegin; 365 PetscCall(MatShellGetContext(A, &matshellctx)); 366 PetscCall(MatAssemblyEnd(matshellctx->Jmf, tp)); 367 PetscFunctionReturn(0); 368 } 369 370 PetscErrorCode PCApply_MyShell(PC pc, Vec x, Vec y) { 371 static PetscInt fail = 0; 372 373 PetscFunctionBegin; 374 PetscCall(VecCopy(x, y)); 375 if (fail++ > 3) { 376 PetscMPIInt rank; 377 PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)pc), &rank)); 378 if (rank == 0) PetscCall(VecSetInf(y)); 379 } 380 PetscFunctionReturn(0); 381 } 382 383 PETSC_EXTERN PetscErrorCode SNESComputeJacobian_DMDA(SNES, Vec, Mat, Mat, void *); 384 385 PetscErrorCode SNESComputeJacobian_MyShell(SNES snes, Vec X, Mat A, Mat B, void *ctx) { 386 static PetscInt fail = 0; 387 388 PetscFunctionBegin; 389 PetscCall(SNESComputeJacobian_DMDA(snes, X, A, B, ctx)); 390 if (fail++ > 0) { PetscCall(MatZeroEntries(A)); } 391 PetscFunctionReturn(0); 392 } 393 394 /*TEST 395 396 test: 397 args: -snes_converged_reason -ksp_converged_reason 398 399 test: 400 suffix: 2 401 args: -snes_converged_reason -ksp_converged_reason -error_in_matmult 402 403 test: 404 suffix: 3 405 args: -snes_converged_reason -ksp_converged_reason -error_in_pcapply 406 407 test: 408 suffix: 4 409 args: -snes_converged_reason -ksp_converged_reason -error_in_pcsetup 410 411 test: 412 suffix: 5 413 args: -snes_converged_reason -ksp_converged_reason -error_in_pcsetup -pc_type bjacobi 414 415 test: 416 suffix: 5_fieldsplit 417 args: -snes_converged_reason -ksp_converged_reason -error_in_pcsetup -pc_type fieldsplit 418 output_file: output/ex69_5.out 419 420 test: 421 suffix: 6 422 args: -snes_converged_reason -ksp_converged_reason -error_in_domainmf -snes_mf -pc_type none 423 424 test: 425 suffix: 7 426 args: -snes_converged_reason -ksp_converged_reason -error_in_domain 427 428 test: 429 suffix: 8 430 args: -snes_converged_reason -ksp_converged_reason -error_in_domain -snes_mf -pc_type none 431 432 TEST*/ 433