PETSc::~PETSc() { if(x!=NULL) { VecDestroy(&x); x = NULL; } if(b!=NULL) { VecDestroy(&b); b = NULL; } if(A!=NULL) { MatDestroy(&A); A = NULL; } if(ksp!=NULL) { KSPDestroy(&ksp); ksp = NULL; } if(nullsp!=NULL) { MatNullSpaceDestroy(&nullsp); nullsp = NULL; } }
PetscErrorCode BSSCR_PCGtKGAttachNullSpace( PC pc ) { PC_GtKG ctx = (PC_GtKG)pc->data; MatNullSpace nsp; BSSCR_pc_error( pc, "__func__" ); /* Attach a null space */ MatNullSpaceCreate( PETSC_COMM_WORLD, PETSC_TRUE, PETSC_NULL, PETSC_NULL, &nsp ); #if ( (PETSC_VERSION_MAJOR >= 3) && (PETSC_VERSION_MINOR <6) ) KSPSetNullSpace( ctx->ksp, nsp ); #else Mat A; KSPGetOperators(ctx->ksp,&A,NULL);//Note: DOES NOT increase the reference counts of the matrix, so you should NOT destroy them. MatSetNullSpace( A, nsp); #endif /* NOTE: This does NOT destroy the memory for nsp, it just decrements the nsp->refct, so that the next time MatNullSpaceDestroy() is called, the memory will be released. The next time this is called will be by KSPDestroy(); */ MatNullSpaceDestroy( nsp ); PetscFunctionReturn(0); }
PetscErrorCode ComputeJacobian(KSP ksp,Mat J, Mat jac,void *ctx) { PetscErrorCode ierr; PetscInt i, j, M, N, xm, ym, xs, ys, num, numi, numj; PetscScalar v[5], Hx, Hy, HydHx, HxdHy; MatStencil row, col[5]; DM da; MatNullSpace nullspace; PetscFunctionBeginUser; ierr = KSPGetDM(ksp,&da);CHKERRQ(ierr); ierr = DMDAGetInfo(da,0,&M,&N,0,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr); Hx = 1.0 / (PetscReal)(M); Hy = 1.0 / (PetscReal)(N); HxdHy = Hx/Hy; HydHx = Hy/Hx; ierr = DMDAGetCorners(da,&xs,&ys,0,&xm,&ym,0);CHKERRQ(ierr); for (j=ys; j<ys+ym; j++) { for (i=xs; i<xs+xm; i++) { row.i = i; row.j = j; if (i==0 || j==0 || i==M-1 || j==N-1) { num=0; numi=0; numj=0; if (j!=0) { v[num] = -HxdHy; col[num].i = i; col[num].j = j-1; num++; numj++; } if (i!=0) { v[num] = -HydHx; col[num].i = i-1; col[num].j = j; num++; numi++; } if (i!=M-1) { v[num] = -HydHx; col[num].i = i+1; col[num].j = j; num++; numi++; } if (j!=N-1) { v[num] = -HxdHy; col[num].i = i; col[num].j = j+1; num++; numj++; } v[num] = ((PetscReal)(numj)*HxdHy + (PetscReal)(numi)*HydHx); col[num].i = i; col[num].j = j; num++; ierr = MatSetValuesStencil(jac,1,&row,num,col,v,INSERT_VALUES);CHKERRQ(ierr); } else { v[0] = -HxdHy; col[0].i = i; col[0].j = j-1; v[1] = -HydHx; col[1].i = i-1; col[1].j = j; v[2] = 2.0*(HxdHy + HydHx); col[2].i = i; col[2].j = j; v[3] = -HydHx; col[3].i = i+1; col[3].j = j; v[4] = -HxdHy; col[4].i = i; col[4].j = j+1; ierr = MatSetValuesStencil(jac,1,&row,5,col,v,INSERT_VALUES);CHKERRQ(ierr); } } } ierr = MatAssemblyBegin(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); ierr = MatAssemblyEnd(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);CHKERRQ(ierr); ierr = MatSetNullSpace(J,nullspace);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullspace);CHKERRQ(ierr); PetscFunctionReturn(0); }
PetscErrorCode MatDestroy_MFFD(Mat mat) { PetscErrorCode ierr; MatMFFD ctx = (MatMFFD)mat->data; PetscFunctionBegin; ierr = VecDestroy(&ctx->w);CHKERRQ(ierr); ierr = VecDestroy(&ctx->drscale);CHKERRQ(ierr); ierr = VecDestroy(&ctx->dlscale);CHKERRQ(ierr); ierr = VecDestroy(&ctx->dshift);CHKERRQ(ierr); if (ctx->current_f_allocated) { ierr = VecDestroy(&ctx->current_f);CHKERRQ(ierr); } if (ctx->ops->destroy) {ierr = (*ctx->ops->destroy)(ctx);CHKERRQ(ierr);} ierr = MatNullSpaceDestroy(&ctx->sp);CHKERRQ(ierr); ierr = PetscHeaderDestroy(&ctx);CHKERRQ(ierr); mat->data = 0; ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMFFDSetBase_C",NULL);CHKERRQ(ierr); ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMFFDSetFunctioniBase_C",NULL);CHKERRQ(ierr); ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMFFDSetFunctioni_C",NULL);CHKERRQ(ierr); ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMFFDSetFunction_C",NULL);CHKERRQ(ierr); ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMFFDSetFunctionError_C",NULL);CHKERRQ(ierr); ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMFFDSetCheckh_C",NULL);CHKERRQ(ierr); ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMFFDSetPeriod_C",NULL);CHKERRQ(ierr); ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMFFDResetHHistory_C",NULL);CHKERRQ(ierr); ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMFFDAddNullSpace_C",NULL);CHKERRQ(ierr); PetscFunctionReturn(0); }
int main(int argc, char **argv) { Mat mat; MatNullSpace nsp; PetscBool prefix = PETSC_FALSE, flg; PetscErrorCode ierr; PetscInt zero = 0; PetscScalar value = 0; ierr = PetscInitialize(&argc, &argv, NULL, help); if (ierr) return ierr; ierr = PetscOptionsGetBool(NULL, NULL, "-with_prefix",&prefix,NULL);CHKERRQ(ierr); ierr = MatCreateDense(PETSC_COMM_WORLD, 1, 1, 1, 1, NULL, &mat);CHKERRQ(ierr); ierr = MatSetOptionsPrefix(mat, prefix ? "prefix_" : NULL);CHKERRQ(ierr); ierr = MatSetUp(mat);CHKERRQ(ierr); ierr = MatSetValues(mat, 1, &zero, 1, &zero, &value, INSERT_VALUES);CHKERRQ(ierr); ierr = MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); ierr = MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); ierr = MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, NULL, &nsp);CHKERRQ(ierr); ierr = MatNullSpaceTest(nsp, mat, &flg);CHKERRQ(ierr); if (!flg) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Null space test failed!"); ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr); ierr = MatDestroy(&mat);CHKERRQ(ierr); ierr = PetscFinalize(); return ierr; }
PetscErrorCode MatMFFDAddNullSpace_MFFD(Mat J,MatNullSpace nullsp) { PetscErrorCode ierr; MatMFFD ctx = (MatMFFD)J->data; PetscFunctionBegin; ierr = PetscObjectReference((PetscObject)nullsp);CHKERRQ(ierr); if (ctx->sp) { ierr = MatNullSpaceDestroy(&ctx->sp);CHKERRQ(ierr); } ctx->sp = nullsp; PetscFunctionReturn(0); }
/*@C DMMGSetNullSpace - Indicates the null space in the linear operator (this is needed by the linear solver) Collective on DMMG Input Parameter: + dmmg - the context . has_cnst - is the constant vector in the null space . n - number of null vectors (excluding the possible constant vector) - func - a function that fills an array of vectors with the null vectors (must be orthonormal), may be PETSC_NULL Level: advanced .seealso DMMGCreate(), DMMGDestroy, DMMGSetDM(), DMMGSolve(), MatNullSpaceCreate(), KSPSetNullSpace(), DMMGSetMatType() @*/ PetscErrorCode PETSCSNES_DLLEXPORT DMMGSetNullSpace(DMMG *dmmg,PetscTruth has_cnst,PetscInt n,PetscErrorCode (*func)(DMMG,Vec[])) { PetscErrorCode ierr; PetscInt i,j,nlevels = dmmg[0]->nlevels; Vec *nulls = 0; MatNullSpace nullsp; KSP iksp; PC pc,ipc; PetscTruth ismg,isred; PetscFunctionBegin; if (!dmmg) SETERRQ(PETSC_ERR_ARG_NULL,"Passing null as DMMG"); if (!dmmg[0]->ksp) SETERRQ(PETSC_ERR_ORDER,"Must call AFTER DMMGSetKSP() or DMMGSetSNES()"); if ((n && !func) || (!n && func)) SETERRQ(PETSC_ERR_ARG_INCOMP,"Both n and func() must be set together"); if (n < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Cannot have negative number of vectors in null space n = %D",n) for (i=0; i<nlevels; i++) { if (n) { ierr = VecDuplicateVecs(dmmg[i]->b,n,&nulls);CHKERRQ(ierr); ierr = (*func)(dmmg[i],nulls);CHKERRQ(ierr); } ierr = MatNullSpaceCreate(dmmg[i]->comm,has_cnst,n,nulls,&nullsp);CHKERRQ(ierr); ierr = KSPSetNullSpace(dmmg[i]->ksp,nullsp);CHKERRQ(ierr); for (j=i; j<nlevels; j++) { ierr = KSPGetPC(dmmg[j]->ksp,&pc);CHKERRQ(ierr); ierr = PetscTypeCompare((PetscObject)pc,PCMG,&ismg);CHKERRQ(ierr); if (ismg) { ierr = PCMGGetSmoother(pc,i,&iksp);CHKERRQ(ierr); ierr = KSPSetNullSpace(iksp, nullsp);CHKERRQ(ierr); } } ierr = MatNullSpaceDestroy(nullsp);CHKERRQ(ierr); if (n) { ierr = VecDestroyVecs(nulls,n);CHKERRQ(ierr); } } /* make all the coarse grid solvers have LU shift since they are singular */ for (i=0; i<nlevels; i++) { ierr = KSPGetPC(dmmg[i]->ksp,&pc);CHKERRQ(ierr); ierr = PetscTypeCompare((PetscObject)pc,PCMG,&ismg);CHKERRQ(ierr); if (ismg) { ierr = PCMGGetSmoother(pc,0,&iksp);CHKERRQ(ierr); ierr = KSPGetPC(iksp,&ipc);CHKERRQ(ierr); ierr = PetscTypeCompare((PetscObject)ipc,PCREDUNDANT,&isred);CHKERRQ(ierr); if (isred) { ierr = PCRedundantGetPC(ipc,&ipc);CHKERRQ(ierr); } ierr = PCFactorSetShiftType(ipc,MAT_SHIFT_POSITIVE_DEFINITE);CHKERRQ(ierr); } } PetscFunctionReturn(0); }
PetscErrorCode SNESMatrixFreeDestroy2_Private(Mat mat) { PetscErrorCode ierr; MFCtx_Private *ctx; PetscFunctionBegin; ierr = MatShellGetContext(mat,(void**)&ctx);CHKERRQ(ierr); ierr = VecDestroy(&ctx->w);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&ctx->sp);CHKERRQ(ierr); if (ctx->jorge || ctx->compute_err) {ierr = SNESDiffParameterDestroy_More(ctx->data);CHKERRQ(ierr);} ierr = PetscFree(ctx);CHKERRQ(ierr); PetscFunctionReturn(0); }
PetscErrorCode CreatePressureNullSpace(DM dm, AppCtx *user, MatNullSpace *nullSpace) { Vec vec, localVec; PetscErrorCode ierr; PetscFunctionBeginUser; ierr = DMGetGlobalVector(dm, &vec);CHKERRQ(ierr); ierr = DMGetLocalVector(dm, &localVec);CHKERRQ(ierr); ierr = VecSet(vec, 0.0);CHKERRQ(ierr); /* Put a constant in for all pressures Could change this to project the constant function onto the pressure space (when that is finished) */ { PetscSection section; PetscInt pStart, pEnd, p; PetscScalar *a; ierr = DMGetDefaultSection(dm, §ion);CHKERRQ(ierr); ierr = PetscSectionGetChart(section, &pStart, &pEnd);CHKERRQ(ierr); ierr = VecGetArray(localVec, &a);CHKERRQ(ierr); for (p = pStart; p < pEnd; ++p) { PetscInt fDim, off, d; ierr = PetscSectionGetFieldDof(section, p, 1, &fDim);CHKERRQ(ierr); ierr = PetscSectionGetFieldOffset(section, p, 1, &off);CHKERRQ(ierr); for (d = 0; d < fDim; ++d) a[off+d] = 1.0; } ierr = VecRestoreArray(localVec, &a);CHKERRQ(ierr); } ierr = DMLocalToGlobalBegin(dm, localVec, INSERT_VALUES, vec);CHKERRQ(ierr); ierr = DMLocalToGlobalEnd(dm, localVec, INSERT_VALUES, vec);CHKERRQ(ierr); ierr = DMRestoreLocalVector(dm, &localVec);CHKERRQ(ierr); ierr = VecNormalize(vec, NULL);CHKERRQ(ierr); if (user->debug) { ierr = PetscPrintf(PetscObjectComm((PetscObject)dm), "Pressure Null Space\n");CHKERRQ(ierr); ierr = VecView(vec, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); } ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject)dm), PETSC_FALSE, 1, &vec, nullSpace);CHKERRQ(ierr); ierr = DMRestoreGlobalVector(dm, &vec);CHKERRQ(ierr); /* New style for field null spaces */ { PetscObject pressure; MatNullSpace nullSpacePres; ierr = DMGetField(dm, 1, &pressure);CHKERRQ(ierr); ierr = MatNullSpaceCreate(PetscObjectComm(pressure), PETSC_TRUE, 0, NULL, &nullSpacePres);CHKERRQ(ierr); ierr = PetscObjectCompose(pressure, "nullspace", (PetscObject) nullSpacePres);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullSpacePres);CHKERRQ(ierr); } PetscFunctionReturn(0); }
int main(int argc, char **argv) { PetscErrorCode ierr; Mat A; KSP ksp; PC pc; IS zero, one; MatNullSpace nullsp; Vec x, b; MPI_Comm comm; PetscInitialize(&argc, &argv, NULL, NULL); comm = PETSC_COMM_WORLD; ierr = MatCreate(comm, &A);CHKERRQ(ierr); ierr = MatSetSizes(A, 4, 4, PETSC_DECIDE, PETSC_DECIDE);CHKERRQ(ierr); ierr = MatSetUp(A);CHKERRQ(ierr); ierr = MatSetFromOptions(A);CHKERRQ(ierr); ierr = MatCreateVecs(A, &x, &b);CHKERRQ(ierr); ierr = VecSet(x, 2.0);CHKERRQ(ierr); ierr = VecSet(b, 12.0);CHKERRQ(ierr); ierr = MatDiagonalSet(A, x, INSERT_VALUES);CHKERRQ(ierr); ierr = MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); ierr = MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); ierr = ISCreateStride(comm, 2, 0, 1, &zero);CHKERRQ(ierr); ierr = ISCreateStride(comm, 2, 2, 1, &one);CHKERRQ(ierr); ierr = MatNullSpaceCreate(comm, PETSC_TRUE, 0, NULL, &nullsp);CHKERRQ(ierr); ierr = PetscObjectCompose((PetscObject)zero, "nullspace",(PetscObject)nullsp);CHKERRQ(ierr); ierr = KSPCreate(comm, &ksp);CHKERRQ(ierr); ierr = KSPSetOperators(ksp, A, A);CHKERRQ(ierr); ierr = KSPSetUp(ksp);CHKERRQ(ierr); ierr = KSPGetPC(ksp, &pc);CHKERRQ(ierr); ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr); ierr = PCFieldSplitSetIS(pc, "0", zero); ierr = PCFieldSplitSetIS(pc, "1", one); ierr = KSPSolve(ksp, b, x);CHKERRQ(ierr); ierr = KSPDestroy(&ksp);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullsp);CHKERRQ(ierr); ierr = ISDestroy(&zero);CHKERRQ(ierr); ierr = ISDestroy(&one);CHKERRQ(ierr); ierr = MatDestroy(&A);CHKERRQ(ierr); ierr = VecDestroy(&x);CHKERRQ(ierr); ierr = VecDestroy(&b);CHKERRQ(ierr); PetscFinalize(); return 0; }
PetscErrorCode ComputeRHS(KSP ksp,Vec b,void *ctx) { UserContext *user = (UserContext*)ctx; PetscErrorCode ierr; PetscInt i,j,mx,my,xm,ym,xs,ys; PetscScalar Hx,Hy; PetscScalar **array; DM da; PetscFunctionBeginUser; ierr = KSPGetDM(ksp,&da); CHKERRQ(ierr); ierr = DMDAGetInfo(da, 0, &mx, &my, 0,0,0,0,0,0,0,0,0,0); CHKERRQ(ierr); Hx = 1.0 / (PetscReal)(mx-1); Hy = 1.0 / (PetscReal)(my-1); ierr = DMDAGetCorners(da,&xs,&ys,0,&xm,&ym,0); CHKERRQ(ierr); ierr = DMDAVecGetArray(da, b, &array); CHKERRQ(ierr); for (j=ys; j<ys+ym; j++) { for (i=xs; i<xs+xm; i++) { array[j][i] = PetscExpScalar(-((PetscReal)i*Hx)*((PetscReal)i*Hx)/user->nu)*PetscExpScalar(-((PetscReal)j*Hy)*((PetscReal)j*Hy)/user->nu)*Hx*Hy; } } ierr = DMDAVecRestoreArray(da, b, &array); CHKERRQ(ierr); ierr = VecAssemblyBegin(b); CHKERRQ(ierr); ierr = VecAssemblyEnd(b); CHKERRQ(ierr); /* force right hand side to be consistent for singular matrix */ /* note this is really a hack, normally the model would provide you with a consistent right handside */ if (user->bcType == NEUMANN) { MatNullSpace nullspace; ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace); CHKERRQ(ierr); ierr = MatNullSpaceRemove(nullspace,b,PETSC_NULL); CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullspace); CHKERRQ(ierr); } PetscFunctionReturn(0); }
PetscErrorCode ComputeRHS(KSP ksp,Vec b,void *ctx) { UserContext *user = (UserContext*)ctx; PetscErrorCode ierr; PetscInt i, j, M, N, xm ,ym ,xs, ys; PetscScalar Hx, Hy, pi, uu, tt; PetscScalar **array; DM da; PetscFunctionBeginUser; ierr = KSPGetDM(ksp,&da);CHKERRQ(ierr); ierr = DMDAGetInfo(da, 0, &M, &N, 0,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr); uu = user->uu; tt = user->tt; pi = 4*atan(1.0); Hx = 1.0/(PetscReal)(M); Hy = 1.0/(PetscReal)(N); ierr = DMDAGetCorners(da,&xs,&ys,0,&xm,&ym,0);CHKERRQ(ierr); // Fine grid //printf(" M N: %d %d; xm ym: %d %d; xs ys: %d %d\n",M,N,xm,ym,xs,ys); ierr = DMDAVecGetArray(da, b, &array);CHKERRQ(ierr); for (j=ys; j<ys+ym; j++){ for (i=xs; i<xs+xm; i++){ array[j][i] = -PetscCosScalar(uu*pi*((PetscReal)i+0.5)*Hx)*cos(tt*pi*((PetscReal)j+0.5)*Hy)*Hx*Hy; } } ierr = DMDAVecRestoreArray(da, b, &array);CHKERRQ(ierr); ierr = VecAssemblyBegin(b);CHKERRQ(ierr); ierr = VecAssemblyEnd(b);CHKERRQ(ierr); /* force right hand side to be consistent for singular matrix */ /* note this is really a hack, normally the model would provide you with a consistent right handside */ if (user->bcType == NEUMANN) { MatNullSpace nullspace; ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);CHKERRQ(ierr); ierr = MatNullSpaceRemove(nullspace,b,PETSC_NULL);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullspace);CHKERRQ(ierr); } PetscFunctionReturn(0); }
PetscErrorCode ComputeRHS(KSP ksp,Vec b,void *ctx) { PetscErrorCode ierr; PetscInt i,j,k,mx,my,mz,xm,ym,zm,xs,ys,zs; PetscScalar Hx,Hy,Hz; PetscScalar ***array; DM da; MatNullSpace nullspace; PetscFunctionBeginUser; ierr = KSPGetDM(ksp,&da);CHKERRQ(ierr); ierr = DMDAGetInfo(da, 0, &mx, &my, &mz, 0,0,0,0,0,0,0,0,0);CHKERRQ(ierr); Hx = 1.0 / (PetscReal)(mx); Hy = 1.0 / (PetscReal)(my); Hz = 1.0 / (PetscReal)(mz); ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr); ierr = DMDAVecGetArray(da, b, &array);CHKERRQ(ierr); for (k=zs; k<zs+zm; k++) { for (j=ys; j<ys+ym; j++) { for (i=xs; i<xs+xm; i++) { array[k][j][i] = 12 * PETSC_PI * PETSC_PI * PetscCosScalar(2*PETSC_PI*(((PetscReal)i+0.5)*Hx)) * PetscCosScalar(2*PETSC_PI*(((PetscReal)j+0.5)*Hy)) * PetscCosScalar(2*PETSC_PI*(((PetscReal)k+0.5)*Hz)) * Hx * Hy * Hz; } } } ierr = DMDAVecRestoreArray(da, b, &array);CHKERRQ(ierr); ierr = VecAssemblyBegin(b);CHKERRQ(ierr); ierr = VecAssemblyEnd(b);CHKERRQ(ierr); /* force right hand side to be consistent for singular matrix */ /* note this is really a hack, normally the model would provide you with a consistent right handside */ ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);CHKERRQ(ierr); ierr = MatNullSpaceRemove(nullspace,b);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullspace);CHKERRQ(ierr); PetscFunctionReturn(0); }
PetscErrorCode ComputeRHS(DM da, Vec b, PetscScalar nu) { PetscErrorCode ierr; PetscInt i, j, mx, my, xm, ym, xs, ys; PetscScalar Hx, Hy; PetscScalar** array; PetscFunctionBeginUser; ierr = DMDAGetInfo(da, 0, &mx, &my, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0); CHKERRQ(ierr); Hx = 1.0 / (PetscReal)(mx); Hy = 1.0 / (PetscReal)(my); ierr = DMDAGetCorners(da, &xs, &ys, 0, &xm, &ym, 0); CHKERRQ(ierr); ierr = DMDAVecGetArray(da, b, &array); CHKERRQ(ierr); for (j = ys; j < ys + ym; j++) { for (i = xs; i < xs + xm; i++) { array[j][i] = PetscExpScalar(-(((PetscReal)i + 0.5) * Hx) * (((PetscReal)i + 0.5) * Hx) / nu) * PetscExpScalar(-(((PetscReal)j + 0.5) * Hy) * (((PetscReal)j + 0.5) * Hy) / nu) * Hx * Hy * nu; } } ierr = DMDAVecRestoreArray(da, b, &array); CHKERRQ(ierr); ierr = VecAssemblyBegin(b); CHKERRQ(ierr); ierr = VecAssemblyEnd(b); CHKERRQ(ierr); MatNullSpace nullspace; ierr = MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, 0, &nullspace); CHKERRQ(ierr); ierr = MatNullSpaceRemove(nullspace, b); CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullspace); CHKERRQ(ierr); PetscFunctionReturn(0); }
/*@ KSPSetFromOptions - Sets KSP options from the options database. This routine must be called before KSPSetUp() if the user is to be allowed to set the Krylov type. Collective on KSP Input Parameters: . ksp - the Krylov space context Options Database Keys: + -ksp_max_it - maximum number of linear iterations . -ksp_rtol rtol - relative tolerance used in default determination of convergence, i.e. if residual norm decreases by this factor than convergence is declared . -ksp_atol abstol - absolute tolerance used in default convergence test, i.e. if residual norm is less than this then convergence is declared . -ksp_divtol tol - if residual norm increases by this factor than divergence is declared . -ksp_converged_use_initial_residual_norm - see KSPConvergedDefaultSetUIRNorm() . -ksp_converged_use_min_initial_residual_norm - see KSPConvergedDefaultSetUMIRNorm() . -ksp_norm_type - none - skip norms used in convergence tests (useful only when not using convergence test (say you always want to run with 5 iterations) to save on communication overhead preconditioned - default for left preconditioning unpreconditioned - see KSPSetNormType() natural - see KSPSetNormType() . -ksp_check_norm_iteration it - do not compute residual norm until iteration number it (does compute at 0th iteration) works only for PCBCGS, PCIBCGS and and PCCG . -ksp_lag_norm - compute the norm of the residual for the ith iteration on the i+1 iteration; this means that one can use the norm of the residual for convergence test WITHOUT an extra MPI_Allreduce() limiting global synchronizations. This will require 1 more iteration of the solver than usual. . -ksp_fischer_guess <model,size> - uses the Fischer initial guess generator for repeated linear solves . -ksp_constant_null_space - assume the operator (matrix) has the constant vector in its null space . -ksp_test_null_space - tests the null space set with KSPSetNullSpace() to see if it truly is a null space . -ksp_knoll - compute initial guess by applying the preconditioner to the right hand side . -ksp_monitor_cancel - cancel all previous convergene monitor routines set . -ksp_monitor <optional filename> - print residual norm at each iteration . -ksp_monitor_lg_residualnorm - plot residual norm at each iteration . -ksp_monitor_solution - plot solution at each iteration - -ksp_monitor_singular_value - monitor extremem singular values at each iteration Notes: To see all options, run your program with the -help option or consult Users-Manual: ch_ksp Level: beginner .keywords: KSP, set, from, options, database .seealso: KSPSetUseFischerGuess() @*/ PetscErrorCode KSPSetFromOptions(KSP ksp) { PetscErrorCode ierr; PetscInt indx; const char *convtests[] = {"default","skip"}; char type[256], monfilename[PETSC_MAX_PATH_LEN]; PetscViewer monviewer; PetscBool flg,flag,reuse; PetscInt model[2]={0,0},nmax; KSPNormType normtype; PCSide pcside; void *ctx; PetscFunctionBegin; PetscValidHeaderSpecific(ksp,KSP_CLASSID,1); if (!ksp->pc) {ierr = KSPGetPC(ksp,&ksp->pc);CHKERRQ(ierr);} ierr = PCSetFromOptions(ksp->pc);CHKERRQ(ierr); if (!KSPRegisterAllCalled) {ierr = KSPRegisterAll();CHKERRQ(ierr);} ierr = PetscObjectOptionsBegin((PetscObject)ksp);CHKERRQ(ierr); ierr = PetscOptionsFList("-ksp_type","Krylov method","KSPSetType",KSPList,(char*)(((PetscObject)ksp)->type_name ? ((PetscObject)ksp)->type_name : KSPGMRES),type,256,&flg);CHKERRQ(ierr); if (flg) { ierr = KSPSetType(ksp,type);CHKERRQ(ierr); } /* Set the type if it was never set. */ if (!((PetscObject)ksp)->type_name) { ierr = KSPSetType(ksp,KSPGMRES);CHKERRQ(ierr); } ierr = PetscOptionsInt("-ksp_max_it","Maximum number of iterations","KSPSetTolerances",ksp->max_it,&ksp->max_it,NULL);CHKERRQ(ierr); ierr = PetscOptionsReal("-ksp_rtol","Relative decrease in residual norm","KSPSetTolerances",ksp->rtol,&ksp->rtol,NULL);CHKERRQ(ierr); ierr = PetscOptionsReal("-ksp_atol","Absolute value of residual norm","KSPSetTolerances",ksp->abstol,&ksp->abstol,NULL);CHKERRQ(ierr); ierr = PetscOptionsReal("-ksp_divtol","Residual norm increase cause divergence","KSPSetTolerances",ksp->divtol,&ksp->divtol,NULL);CHKERRQ(ierr); flag = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_converged_use_initial_residual_norm","Use initial residual residual norm for computing relative convergence","KSPConvergedDefaultSetUIRNorm",flag,&flag,NULL);CHKERRQ(ierr); if (flag) {ierr = KSPConvergedDefaultSetUIRNorm(ksp);CHKERRQ(ierr);} flag = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_converged_use_min_initial_residual_norm","Use minimum of initial residual norm and b for computing relative convergence","KSPConvergedDefaultSetUMIRNorm",flag,&flag,NULL);CHKERRQ(ierr); if (flag) {ierr = KSPConvergedDefaultSetUMIRNorm(ksp);CHKERRQ(ierr);} ierr = KSPGetInitialGuessNonzero(ksp,&flag);CHKERRQ(ierr); ierr = PetscOptionsBool("-ksp_initial_guess_nonzero","Use the contents of the solution vector for initial guess","KSPSetInitialNonzero",flag,&flag,&flg);CHKERRQ(ierr); if (flg) { ierr = KSPSetInitialGuessNonzero(ksp,flag);CHKERRQ(ierr); } ierr = PCGetReusePreconditioner(ksp->pc,&reuse);CHKERRQ(ierr); ierr = PetscOptionsBool("-ksp_reuse_preconditioner","Use initial preconditioner and don't ever compute a new one ","KSPReusePreconditioner",reuse,&reuse,NULL);CHKERRQ(ierr); ierr = KSPSetReusePreconditioner(ksp,reuse);CHKERRQ(ierr); ierr = PetscOptionsBool("-ksp_knoll","Use preconditioner applied to b for initial guess","KSPSetInitialGuessKnoll",ksp->guess_knoll,&ksp->guess_knoll,NULL);CHKERRQ(ierr); ierr = PetscOptionsBool("-ksp_error_if_not_converged","Generate error if solver does not converge","KSPSetErrorIfNotConverged",ksp->errorifnotconverged,&ksp->errorifnotconverged,NULL);CHKERRQ(ierr); nmax = 2; ierr = PetscOptionsIntArray("-ksp_fischer_guess","Use Paul Fischer's algorithm for initial guess","KSPSetUseFischerGuess",model,&nmax,&flag);CHKERRQ(ierr); if (flag) { if (nmax != 2) SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_ARG_OUTOFRANGE,"Must pass in model,size as arguments"); ierr = KSPSetUseFischerGuess(ksp,model[0],model[1]);CHKERRQ(ierr); } ierr = PetscOptionsEList("-ksp_convergence_test","Convergence test","KSPSetConvergenceTest",convtests,2,"default",&indx,&flg);CHKERRQ(ierr); if (flg) { switch (indx) { case 0: ierr = KSPConvergedDefaultCreate(&ctx);CHKERRQ(ierr); ierr = KSPSetConvergenceTest(ksp,KSPConvergedDefault,ctx,KSPConvergedDefaultDestroy);CHKERRQ(ierr); break; case 1: ierr = KSPSetConvergenceTest(ksp,KSPConvergedSkip,NULL,NULL);CHKERRQ(ierr); break; } } ierr = KSPSetUpNorms_Private(ksp,&normtype,&pcside);CHKERRQ(ierr); ierr = PetscOptionsEnum("-ksp_norm_type","KSP Norm type","KSPSetNormType",KSPNormTypes,(PetscEnum)normtype,(PetscEnum*)&normtype,&flg);CHKERRQ(ierr); if (flg) { ierr = KSPSetNormType(ksp,normtype);CHKERRQ(ierr); } ierr = PetscOptionsInt("-ksp_check_norm_iteration","First iteration to compute residual norm","KSPSetCheckNormIteration",ksp->chknorm,&ksp->chknorm,NULL);CHKERRQ(ierr); flag = ksp->lagnorm; ierr = PetscOptionsBool("-ksp_lag_norm","Lag the calculation of the residual norm","KSPSetLagNorm",flag,&flag,&flg);CHKERRQ(ierr); if (flg) { ierr = KSPSetLagNorm(ksp,flag);CHKERRQ(ierr); } ierr = KSPGetDiagonalScale(ksp,&flag);CHKERRQ(ierr); ierr = PetscOptionsBool("-ksp_diagonal_scale","Diagonal scale matrix before building preconditioner","KSPSetDiagonalScale",flag,&flag,&flg);CHKERRQ(ierr); if (flg) { ierr = KSPSetDiagonalScale(ksp,flag);CHKERRQ(ierr); } ierr = KSPGetDiagonalScaleFix(ksp,&flag);CHKERRQ(ierr); ierr = PetscOptionsBool("-ksp_diagonal_scale_fix","Fix diagonally scaled matrix after solve","KSPSetDiagonalScaleFix",flag,&flag,&flg);CHKERRQ(ierr); if (flg) { ierr = KSPSetDiagonalScaleFix(ksp,flag);CHKERRQ(ierr); } flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_constant_null_space","Add constant null space to Krylov solver","KSPSetNullSpace",flg,&flg,NULL);CHKERRQ(ierr); if (flg) { MatNullSpace nsp; ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject)ksp),PETSC_TRUE,0,0,&nsp);CHKERRQ(ierr); ierr = KSPSetNullSpace(ksp,nsp);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr); } /* option is actually checked in KSPSetUp(), just here so goes into help message */ if (ksp->nullsp) { ierr = PetscOptionsName("-ksp_test_null_space","Is provided null space correct","None",&flg);CHKERRQ(ierr); } /* Prints reason for convergence or divergence of each linear solve */ flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_converged_reason","Print reason for converged or diverged","KSPSolve",flg,&flg,NULL);CHKERRQ(ierr); if (flg) ksp->printreason = PETSC_TRUE; flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_monitor_cancel","Remove any hardwired monitor routines","KSPMonitorCancel",flg,&flg,NULL);CHKERRQ(ierr); /* -----------------------------------------------------------------------*/ /* Cancels all monitors hardwired into code before call to KSPSetFromOptions() */ if (flg) { ierr = KSPMonitorCancel(ksp);CHKERRQ(ierr); } /* Prints preconditioned residual norm at each iteration */ ierr = PetscOptionsString("-ksp_monitor","Monitor preconditioned residual norm","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr); if (flg) { ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorDefault,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr); } /* Prints preconditioned residual norm at each iteration */ ierr = PetscOptionsString("-ksp_monitor_range","Monitor percent of residual entries more than 10 percent of max","KSPMonitorRange","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr); if (flg) { ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorRange,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr); } ierr = PetscObjectTypeCompare((PetscObject)ksp->pc,PCKSP,&flg);CHKERRQ(ierr); ierr = PetscObjectTypeCompare((PetscObject)ksp->pc,PCBJACOBI,&flag);CHKERRQ(ierr); if (flg || flag) { /* A hack for using dynamic tolerance in preconditioner */ ierr = PetscOptionsString("-sub_ksp_dynamic_tolerance","Use dynamic tolerance for PC if PC is a KSP","KSPMonitorDynamicTolerance","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr); if (flg) { KSPDynTolCtx *scale = NULL; PetscReal defaultv = 1.0; ierr = PetscMalloc1(1,&scale);CHKERRQ(ierr); scale->bnrm = -1.0; scale->coef = defaultv; ierr = PetscOptionsReal("-sub_ksp_dynamic_tolerance_param","Parameter of dynamic tolerance for inner PCKSP","KSPMonitorDynamicToleranceParam",defaultv,&(scale->coef),&flg);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorDynamicTolerance,scale,KSPMonitorDynamicToleranceDestroy);CHKERRQ(ierr); } } /* Plots the vector solution */ flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_monitor_solution","Monitor solution graphically","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr); if (flg) { ierr = KSPMonitorSet(ksp,KSPMonitorSolution,NULL,NULL);CHKERRQ(ierr); } /* Prints preconditioned and true residual norm at each iteration */ ierr = PetscOptionsString("-ksp_monitor_true_residual","Monitor true residual norm","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr); if (flg) { ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorTrueResidualNorm,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr); } /* Prints with max norm at each iteration */ ierr = PetscOptionsString("-ksp_monitor_max","Monitor true residual max norm","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr); if (flg) { ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorTrueResidualMaxNorm,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr); } /* Prints extreme eigenvalue estimates at each iteration */ ierr = PetscOptionsString("-ksp_monitor_singular_value","Monitor singular values","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr); if (flg) { ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr); ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorSingularValue,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr); } /* Prints preconditioned residual norm with fewer digits */ ierr = PetscOptionsString("-ksp_monitor_short","Monitor preconditioned residual norm with fewer digits","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr); if (flg) { ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorDefaultShort,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr); } /* Calls Python function */ ierr = PetscOptionsString("-ksp_monitor_python","Use Python function","KSPMonitorSet",0,monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr); if (flg) {ierr = PetscPythonMonitorSet((PetscObject)ksp,monfilename);CHKERRQ(ierr);} /* Graphically plots preconditioned residual norm */ flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_monitor_lg_residualnorm","Monitor graphically preconditioned residual norm","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr); if (flg) { PetscDrawLG ctx; ierr = KSPMonitorLGResidualNormCreate(0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,&ctx);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorLGResidualNorm,ctx,(PetscErrorCode (*)(void**))KSPMonitorLGResidualNormDestroy);CHKERRQ(ierr); } /* Graphically plots preconditioned and true residual norm */ flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_monitor_lg_true_residualnorm","Monitor graphically true residual norm","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr); if (flg) { PetscDrawLG ctx; ierr = KSPMonitorLGTrueResidualNormCreate(PetscObjectComm((PetscObject)ksp),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,&ctx);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorLGTrueResidualNorm,ctx,(PetscErrorCode (*)(void**))KSPMonitorLGTrueResidualNormDestroy);CHKERRQ(ierr); } /* Graphically plots preconditioned residual norm and range of residual element values */ flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_monitor_lg_range","Monitor graphically range of preconditioned residual norm","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr); if (flg) { PetscViewer ctx; ierr = PetscViewerDrawOpen(PetscObjectComm((PetscObject)ksp),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,&ctx);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorLGRange,ctx,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr); } #if defined(PETSC_HAVE_SAWS) /* Publish convergence information using AMS */ flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_monitor_saws","Publish KSP progress using SAWs","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr); if (flg) { void *ctx; ierr = KSPMonitorSAWsCreate(ksp,&ctx);CHKERRQ(ierr); ierr = KSPMonitorSet(ksp,KSPMonitorSAWs,ctx,KSPMonitorSAWsDestroy);CHKERRQ(ierr); ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr); } #endif /* -----------------------------------------------------------------------*/ ierr = KSPSetUpNorms_Private(ksp,&normtype,&pcside);CHKERRQ(ierr); ierr = PetscOptionsEnum("-ksp_pc_side","KSP preconditioner side","KSPSetPCSide",PCSides,(PetscEnum)pcside,(PetscEnum*)&pcside,&flg);CHKERRQ(ierr); if (flg) {ierr = KSPSetPCSide(ksp,pcside);CHKERRQ(ierr);} flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_compute_singularvalues","Compute singular values of preconditioned operator","KSPSetComputeSingularValues",flg,&flg,NULL);CHKERRQ(ierr); if (flg) { ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr); } flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_compute_eigenvalues","Compute eigenvalues of preconditioned operator","KSPSetComputeSingularValues",flg,&flg,NULL);CHKERRQ(ierr); if (flg) { ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr); } flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_plot_eigenvalues","Scatter plot extreme eigenvalues","KSPSetComputeSingularValues",flg,&flg,NULL);CHKERRQ(ierr); if (flg) { ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr); } #if defined(PETSC_HAVE_SAWS) { PetscBool set; flg = PETSC_FALSE; ierr = PetscOptionsBool("-ksp_saws_block","Block for SAWs at end of KSPSolve","PetscObjectSAWsBlock",((PetscObject)ksp)->amspublishblock,&flg,&set);CHKERRQ(ierr); if (set) { ierr = PetscObjectSAWsSetBlock((PetscObject)ksp,flg);CHKERRQ(ierr); } } #endif if (ksp->ops->setfromoptions) { ierr = (*ksp->ops->setfromoptions)(ksp);CHKERRQ(ierr); } /* process any options handlers added with PetscObjectAddOptionsHandler() */ ierr = PetscObjectProcessOptionsHandlers((PetscObject)ksp);CHKERRQ(ierr); ierr = PetscOptionsEnd();CHKERRQ(ierr); PetscFunctionReturn(0); }
PetscErrorCode PCISSetUp(PC pc) { PC_IS *pcis = (PC_IS*)(pc->data); Mat_IS *matis; PetscErrorCode ierr; PetscBool flg,issbaij; Vec counter; PetscFunctionBegin; ierr = PetscObjectTypeCompare((PetscObject)pc->pmat,MATIS,&flg);CHKERRQ(ierr); if (!flg) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_ARG_WRONG,"Preconditioner type of Neumann Neumman requires matrix of type MATIS"); matis = (Mat_IS*)pc->pmat->data; pcis->pure_neumann = matis->pure_neumann; /* get info on mapping */ ierr = PetscObjectReference((PetscObject)matis->mapping);CHKERRQ(ierr); ierr = ISLocalToGlobalMappingDestroy(&pcis->mapping);CHKERRQ(ierr); pcis->mapping = matis->mapping; ierr = ISLocalToGlobalMappingGetSize(pcis->mapping,&pcis->n);CHKERRQ(ierr); ierr = ISLocalToGlobalMappingGetInfo(pcis->mapping,&(pcis->n_neigh),&(pcis->neigh),&(pcis->n_shared),&(pcis->shared));CHKERRQ(ierr); /* Creating local and global index sets for interior and inteface nodes. */ { PetscInt n_I; PetscInt *idx_I_local,*idx_B_local,*idx_I_global,*idx_B_global; PetscInt *array; PetscInt i,j; /* Identifying interior and interface nodes, in local numbering */ ierr = PetscMalloc1(pcis->n,&array);CHKERRQ(ierr); ierr = PetscMemzero(array,pcis->n*sizeof(PetscInt));CHKERRQ(ierr); for (i=0;i<pcis->n_neigh;i++) for (j=0;j<pcis->n_shared[i];j++) array[pcis->shared[i][j]] += 1; ierr = PetscMalloc1(pcis->n,&idx_I_local);CHKERRQ(ierr); ierr = PetscMalloc1(pcis->n,&idx_B_local);CHKERRQ(ierr); for (i=0, pcis->n_B=0, n_I=0; i<pcis->n; i++) { if (!array[i]) { idx_I_local[n_I] = i; n_I++; } else { idx_B_local[pcis->n_B] = i; pcis->n_B++; } } /* Getting the global numbering */ idx_B_global = idx_I_local + n_I; /* Just avoiding allocating extra memory, since we have vacant space */ idx_I_global = idx_B_local + pcis->n_B; ierr = ISLocalToGlobalMappingApply(pcis->mapping,pcis->n_B,idx_B_local,idx_B_global);CHKERRQ(ierr); ierr = ISLocalToGlobalMappingApply(pcis->mapping,n_I, idx_I_local,idx_I_global);CHKERRQ(ierr); /* Creating the index sets. */ ierr = ISCreateGeneral(PETSC_COMM_SELF,pcis->n_B,idx_B_local,PETSC_COPY_VALUES, &pcis->is_B_local);CHKERRQ(ierr); ierr = ISCreateGeneral(PETSC_COMM_SELF,pcis->n_B,idx_B_global,PETSC_COPY_VALUES,&pcis->is_B_global);CHKERRQ(ierr); ierr = ISCreateGeneral(PETSC_COMM_SELF,n_I,idx_I_local,PETSC_COPY_VALUES, &pcis->is_I_local);CHKERRQ(ierr); ierr = ISCreateGeneral(PETSC_COMM_SELF,n_I,idx_I_global,PETSC_COPY_VALUES,&pcis->is_I_global);CHKERRQ(ierr); /* Freeing memory and restoring arrays */ ierr = PetscFree(idx_B_local);CHKERRQ(ierr); ierr = PetscFree(idx_I_local);CHKERRQ(ierr); ierr = PetscFree(array);CHKERRQ(ierr); } /* Extracting the blocks A_II, A_BI, A_IB and A_BB from A. If the numbering is such that interior nodes come first than the interface ones, we have [ | ] [ A_II | A_IB ] A = [ | ] [-----------+------] [ A_BI | A_BB ] */ ierr = MatGetSubMatrix(matis->A,pcis->is_I_local,pcis->is_I_local,MAT_INITIAL_MATRIX,&pcis->A_II);CHKERRQ(ierr); ierr = MatGetSubMatrix(matis->A,pcis->is_B_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&pcis->A_BB);CHKERRQ(ierr); ierr = PetscObjectTypeCompare((PetscObject)matis->A,MATSEQSBAIJ,&issbaij);CHKERRQ(ierr); if (!issbaij) { ierr = MatGetSubMatrix(matis->A,pcis->is_I_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&pcis->A_IB);CHKERRQ(ierr); ierr = MatGetSubMatrix(matis->A,pcis->is_B_local,pcis->is_I_local,MAT_INITIAL_MATRIX,&pcis->A_BI);CHKERRQ(ierr); } else { Mat newmat; ierr = MatConvert(matis->A,MATSEQBAIJ,MAT_INITIAL_MATRIX,&newmat);CHKERRQ(ierr); ierr = MatGetSubMatrix(newmat,pcis->is_I_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&pcis->A_IB);CHKERRQ(ierr); ierr = MatGetSubMatrix(newmat,pcis->is_B_local,pcis->is_I_local,MAT_INITIAL_MATRIX,&pcis->A_BI);CHKERRQ(ierr); ierr = MatDestroy(&newmat);CHKERRQ(ierr); } /* Creating work vectors and arrays */ ierr = VecDuplicate(matis->x,&pcis->vec1_N);CHKERRQ(ierr); ierr = VecDuplicate(pcis->vec1_N,&pcis->vec2_N);CHKERRQ(ierr); ierr = VecCreateSeq(PETSC_COMM_SELF,pcis->n-pcis->n_B,&pcis->vec1_D);CHKERRQ(ierr); ierr = VecDuplicate(pcis->vec1_D,&pcis->vec2_D);CHKERRQ(ierr); ierr = VecDuplicate(pcis->vec1_D,&pcis->vec3_D);CHKERRQ(ierr); ierr = VecDuplicate(pcis->vec1_D,&pcis->vec4_D);CHKERRQ(ierr); ierr = VecCreateSeq(PETSC_COMM_SELF,pcis->n_B,&pcis->vec1_B);CHKERRQ(ierr); ierr = VecDuplicate(pcis->vec1_B,&pcis->vec2_B);CHKERRQ(ierr); ierr = VecDuplicate(pcis->vec1_B,&pcis->vec3_B);CHKERRQ(ierr); ierr = MatCreateVecs(pc->pmat,&pcis->vec1_global,0);CHKERRQ(ierr); ierr = PetscMalloc1(pcis->n,&pcis->work_N);CHKERRQ(ierr); /* Creating the scatter contexts */ ierr = VecScatterCreate(pcis->vec1_global,pcis->is_I_global,pcis->vec1_D,(IS)0,&pcis->global_to_D);CHKERRQ(ierr); ierr = VecScatterCreate(pcis->vec1_N,pcis->is_B_local,pcis->vec1_B,(IS)0,&pcis->N_to_B);CHKERRQ(ierr); ierr = VecScatterCreate(pcis->vec1_global,pcis->is_B_global,pcis->vec1_B,(IS)0,&pcis->global_to_B);CHKERRQ(ierr); /* Creating scaling "matrix" D */ ierr = PetscOptionsGetBool(((PetscObject)pc)->prefix,"-pc_is_use_stiffness_scaling",&pcis->use_stiffness_scaling,NULL);CHKERRQ(ierr); if (!pcis->D) { ierr = VecDuplicate(pcis->vec1_B,&pcis->D);CHKERRQ(ierr); if (!pcis->use_stiffness_scaling) { ierr = VecSet(pcis->D,pcis->scaling_factor);CHKERRQ(ierr); } else { ierr = MatGetDiagonal(matis->A,pcis->vec1_N);CHKERRQ(ierr); ierr = VecScatterBegin(pcis->N_to_B,pcis->vec1_N,pcis->D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); ierr = VecScatterEnd (pcis->N_to_B,pcis->vec1_N,pcis->D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); } } ierr = VecCopy(pcis->D,pcis->vec1_B);CHKERRQ(ierr); ierr = MatCreateVecs(pc->pmat,&counter,0);CHKERRQ(ierr); /* temporary auxiliar vector */ ierr = VecSet(counter,0.0);CHKERRQ(ierr); ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,counter,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); ierr = VecScatterEnd (pcis->global_to_B,pcis->vec1_B,counter,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); ierr = VecScatterBegin(pcis->global_to_B,counter,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); ierr = VecScatterEnd (pcis->global_to_B,counter,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); ierr = VecPointwiseDivide(pcis->D,pcis->D,pcis->vec1_B);CHKERRQ(ierr); ierr = VecDestroy(&counter);CHKERRQ(ierr); /* See historical note 01, at the bottom of this file. */ /* Creating the KSP contexts for the local Dirichlet and Neumann problems. */ if (pcis->computesolvers) { PC pc_ctx; /* Dirichlet */ ierr = KSPCreate(PETSC_COMM_SELF,&pcis->ksp_D);CHKERRQ(ierr); ierr = PetscObjectIncrementTabLevel((PetscObject)pcis->ksp_D,(PetscObject)pc,1);CHKERRQ(ierr); ierr = KSPSetOperators(pcis->ksp_D,pcis->A_II,pcis->A_II);CHKERRQ(ierr); ierr = KSPSetOptionsPrefix(pcis->ksp_D,"is_localD_");CHKERRQ(ierr); ierr = KSPGetPC(pcis->ksp_D,&pc_ctx);CHKERRQ(ierr); ierr = PCSetType(pc_ctx,PCLU);CHKERRQ(ierr); ierr = KSPSetType(pcis->ksp_D,KSPPREONLY);CHKERRQ(ierr); ierr = KSPSetFromOptions(pcis->ksp_D);CHKERRQ(ierr); /* the vectors in the following line are dummy arguments, just telling the KSP the vector size. Values are not used */ ierr = KSPSetUp(pcis->ksp_D);CHKERRQ(ierr); /* Neumann */ ierr = KSPCreate(PETSC_COMM_SELF,&pcis->ksp_N);CHKERRQ(ierr); ierr = PetscObjectIncrementTabLevel((PetscObject)pcis->ksp_N,(PetscObject)pc,1);CHKERRQ(ierr); ierr = KSPSetOperators(pcis->ksp_N,matis->A,matis->A);CHKERRQ(ierr); ierr = KSPSetOptionsPrefix(pcis->ksp_N,"is_localN_");CHKERRQ(ierr); ierr = KSPGetPC(pcis->ksp_N,&pc_ctx);CHKERRQ(ierr); ierr = PCSetType(pc_ctx,PCLU);CHKERRQ(ierr); ierr = KSPSetType(pcis->ksp_N,KSPPREONLY);CHKERRQ(ierr); ierr = KSPSetFromOptions(pcis->ksp_N);CHKERRQ(ierr); { PetscBool damp_fixed = PETSC_FALSE, remove_nullspace_fixed = PETSC_FALSE, set_damping_factor_floating = PETSC_FALSE, not_damp_floating = PETSC_FALSE, not_remove_nullspace_floating = PETSC_FALSE; PetscReal fixed_factor, floating_factor; ierr = PetscOptionsGetReal(((PetscObject)pc_ctx)->prefix,"-pc_is_damp_fixed",&fixed_factor,&damp_fixed);CHKERRQ(ierr); if (!damp_fixed) fixed_factor = 0.0; ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_damp_fixed",&damp_fixed,NULL);CHKERRQ(ierr); ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_remove_nullspace_fixed",&remove_nullspace_fixed,NULL);CHKERRQ(ierr); ierr = PetscOptionsGetReal(((PetscObject)pc_ctx)->prefix,"-pc_is_set_damping_factor_floating", &floating_factor,&set_damping_factor_floating);CHKERRQ(ierr); if (!set_damping_factor_floating) floating_factor = 0.0; ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_set_damping_factor_floating",&set_damping_factor_floating,NULL);CHKERRQ(ierr); if (!set_damping_factor_floating) floating_factor = 1.e-12; ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_not_damp_floating",¬_damp_floating,NULL);CHKERRQ(ierr); ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_not_remove_nullspace_floating",¬_remove_nullspace_floating,NULL);CHKERRQ(ierr); if (pcis->pure_neumann) { /* floating subdomain */ if (!(not_damp_floating)) { ierr = PCFactorSetShiftType(pc_ctx,MAT_SHIFT_NONZERO);CHKERRQ(ierr); ierr = PCFactorSetShiftAmount(pc_ctx,floating_factor);CHKERRQ(ierr); } if (!(not_remove_nullspace_floating)) { MatNullSpace nullsp; ierr = MatNullSpaceCreate(PETSC_COMM_SELF,PETSC_TRUE,0,NULL,&nullsp);CHKERRQ(ierr); ierr = KSPSetNullSpace(pcis->ksp_N,nullsp);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullsp);CHKERRQ(ierr); } } else { /* fixed subdomain */ if (damp_fixed) { ierr = PCFactorSetShiftType(pc_ctx,MAT_SHIFT_NONZERO);CHKERRQ(ierr); ierr = PCFactorSetShiftAmount(pc_ctx,floating_factor);CHKERRQ(ierr); } if (remove_nullspace_fixed) { MatNullSpace nullsp; ierr = MatNullSpaceCreate(PETSC_COMM_SELF,PETSC_TRUE,0,NULL,&nullsp);CHKERRQ(ierr); ierr = KSPSetNullSpace(pcis->ksp_N,nullsp);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullsp);CHKERRQ(ierr); } } } /* the vectors in the following line are dummy arguments, just telling the KSP the vector size. Values are not used */ ierr = KSPSetUp(pcis->ksp_N);CHKERRQ(ierr); } PetscFunctionReturn(0); }
int main(int argc,char **args) { Mat Amat; PetscErrorCode ierr; SNES snes; KSP ksp; MPI_Comm comm; PetscMPIInt npe,rank; PetscLogStage stage[7]; PetscBool test_nonzero_cols=PETSC_FALSE,use_nearnullspace=PETSC_TRUE; Vec xx,bb; PetscInt iter,i,N,dim=3,cells[3]={1,1,1},max_conv_its,local_sizes[7],run_type=1; DM dm,distdm,basedm; PetscBool flg; char convType[256]; PetscReal Lx,mdisp[10],err[10]; const char * const options[10] = {"-ex56_dm_refine 0", "-ex56_dm_refine 1", "-ex56_dm_refine 2", "-ex56_dm_refine 3", "-ex56_dm_refine 4", "-ex56_dm_refine 5", "-ex56_dm_refine 6", "-ex56_dm_refine 7", "-ex56_dm_refine 8", "-ex56_dm_refine 9"}; PetscFunctionBeginUser; ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; comm = PETSC_COMM_WORLD; ierr = MPI_Comm_rank(comm, &rank);CHKERRQ(ierr); ierr = MPI_Comm_size(comm, &npe);CHKERRQ(ierr); /* options */ ierr = PetscOptionsBegin(comm,NULL,"3D bilinear Q1 elasticity options","");CHKERRQ(ierr); { i = 3; ierr = PetscOptionsIntArray("-cells", "Number of (flux tube) processor in each dimension", "ex56.c", cells, &i, NULL);CHKERRQ(ierr); Lx = 1.; /* or ne for rod */ max_conv_its = 3; ierr = PetscOptionsInt("-max_conv_its","Number of iterations in convergence study","",max_conv_its,&max_conv_its,NULL);CHKERRQ(ierr); if (max_conv_its<=0 || max_conv_its>7) SETERRQ1(PETSC_COMM_WORLD, PETSC_ERR_USER, "Bad number of iterations for convergence test (%D)",max_conv_its); ierr = PetscOptionsReal("-lx","Length of domain","",Lx,&Lx,NULL);CHKERRQ(ierr); ierr = PetscOptionsReal("-alpha","material coefficient inside circle","",s_soft_alpha,&s_soft_alpha,NULL);CHKERRQ(ierr); ierr = PetscOptionsBool("-test_nonzero_cols","nonzero test","",test_nonzero_cols,&test_nonzero_cols,NULL);CHKERRQ(ierr); ierr = PetscOptionsBool("-use_mat_nearnullspace","MatNearNullSpace API test","",use_nearnullspace,&use_nearnullspace,NULL);CHKERRQ(ierr); ierr = PetscOptionsInt("-run_type","0: twisting load on cantalever, 1: 3rd order accurate convergence test","",run_type,&run_type,NULL);CHKERRQ(ierr); i = 3; ierr = PetscOptionsInt("-mat_block_size","","",i,&i,&flg);CHKERRQ(ierr); if (!flg || i!=3) SETERRQ2(PETSC_COMM_WORLD, PETSC_ERR_USER, "'-mat_block_size 3' must be set (%D) and = 3 (%D)",flg,flg? i : 3); } ierr = PetscOptionsEnd();CHKERRQ(ierr); ierr = PetscLogStageRegister("Mesh Setup", &stage[6]);CHKERRQ(ierr); ierr = PetscLogStageRegister("1st Setup", &stage[0]);CHKERRQ(ierr); ierr = PetscLogStageRegister("1st Solve", &stage[1]);CHKERRQ(ierr); /* create DM, Plex calls DMSetup */ ierr = PetscLogStagePush(stage[6]);CHKERRQ(ierr); ierr = DMPlexCreateHexBoxMesh(comm, dim, cells, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, &dm);CHKERRQ(ierr); { DMLabel label; IS is; ierr = DMCreateLabel(dm, "boundary");CHKERRQ(ierr); ierr = DMGetLabel(dm, "boundary", &label);CHKERRQ(ierr); ierr = DMPlexMarkBoundaryFaces(dm, label);CHKERRQ(ierr); if (run_type==0) { ierr = DMGetStratumIS(dm, "boundary", 1, &is);CHKERRQ(ierr); ierr = DMCreateLabel(dm,"Faces");CHKERRQ(ierr); if (is) { PetscInt d, f, Nf; const PetscInt *faces; PetscInt csize; PetscSection cs; Vec coordinates ; DM cdm; ierr = ISGetLocalSize(is, &Nf);CHKERRQ(ierr); ierr = ISGetIndices(is, &faces);CHKERRQ(ierr); ierr = DMGetCoordinatesLocal(dm, &coordinates);CHKERRQ(ierr); ierr = DMGetCoordinateDM(dm, &cdm);CHKERRQ(ierr); ierr = DMGetDefaultSection(cdm, &cs);CHKERRQ(ierr); /* Check for each boundary face if any component of its centroid is either 0.0 or 1.0 */ for (f = 0; f < Nf; ++f) { PetscReal faceCoord; PetscInt b,v; PetscScalar *coords = NULL; PetscInt Nv; ierr = DMPlexVecGetClosure(cdm, cs, coordinates, faces[f], &csize, &coords);CHKERRQ(ierr); Nv = csize/dim; /* Calculate mean coordinate vector */ for (d = 0; d < dim; ++d) { faceCoord = 0.0; for (v = 0; v < Nv; ++v) faceCoord += PetscRealPart(coords[v*dim+d]); faceCoord /= Nv; for (b = 0; b < 2; ++b) { if (PetscAbs(faceCoord - b) < PETSC_SMALL) { /* domain have not been set yet, still [0,1]^3 */ ierr = DMSetLabelValue(dm, "Faces", faces[f], d*2+b+1);CHKERRQ(ierr); } } } ierr = DMPlexVecRestoreClosure(cdm, cs, coordinates, faces[f], &csize, &coords);CHKERRQ(ierr); } ierr = ISRestoreIndices(is, &faces);CHKERRQ(ierr); } ierr = ISDestroy(&is);CHKERRQ(ierr); ierr = DMGetLabel(dm, "Faces", &label);CHKERRQ(ierr); ierr = DMPlexLabelComplete(dm, label);CHKERRQ(ierr); } } { PetscInt dimEmbed, i; PetscInt nCoords; PetscScalar *coords,bounds[] = {0,Lx,-.5,.5,-.5,.5,}; /* x_min,x_max,y_min,y_max */ Vec coordinates; if (run_type==1) { for (i = 0; i < 2*dim; i++) bounds[i] = (i%2) ? 1 : 0; } ierr = DMGetCoordinatesLocal(dm,&coordinates);CHKERRQ(ierr); ierr = DMGetCoordinateDim(dm,&dimEmbed);CHKERRQ(ierr); if (dimEmbed != dim) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"dimEmbed != dim %D",dimEmbed);CHKERRQ(ierr); ierr = VecGetLocalSize(coordinates,&nCoords);CHKERRQ(ierr); if (nCoords % dimEmbed) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Coordinate vector the wrong size");CHKERRQ(ierr); ierr = VecGetArray(coordinates,&coords);CHKERRQ(ierr); for (i = 0; i < nCoords; i += dimEmbed) { PetscInt j; PetscScalar *coord = &coords[i]; for (j = 0; j < dimEmbed; j++) { coord[j] = bounds[2 * j] + coord[j] * (bounds[2 * j + 1] - bounds[2 * j]); } } ierr = VecRestoreArray(coordinates,&coords);CHKERRQ(ierr); ierr = DMSetCoordinatesLocal(dm,coordinates);CHKERRQ(ierr); } /* convert to p4est, and distribute */ ierr = PetscOptionsBegin(comm, "", "Mesh conversion options", "DMPLEX");CHKERRQ(ierr); ierr = PetscOptionsFList("-dm_type","Convert DMPlex to another format (should not be Plex!)","ex56.c",DMList,DMPLEX,convType,256,&flg);CHKERRQ(ierr); ierr = PetscOptionsEnd(); if (flg) { DM newdm; ierr = DMConvert(dm,convType,&newdm);CHKERRQ(ierr); if (newdm) { const char *prefix; PetscBool isForest; ierr = PetscObjectGetOptionsPrefix((PetscObject)dm,&prefix);CHKERRQ(ierr); ierr = PetscObjectSetOptionsPrefix((PetscObject)newdm,prefix);CHKERRQ(ierr); ierr = DMIsForest(newdm,&isForest);CHKERRQ(ierr); if (isForest) { } else SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_USER, "Converted to non Forest?"); ierr = DMDestroy(&dm);CHKERRQ(ierr); dm = newdm; } else SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_USER, "Convert failed?"); } else { /* Plex Distribute mesh over processes */ ierr = DMPlexDistribute(dm, 0, NULL, &distdm);CHKERRQ(ierr); if (distdm) { const char *prefix; ierr = PetscObjectGetOptionsPrefix((PetscObject)dm,&prefix);CHKERRQ(ierr); ierr = PetscObjectSetOptionsPrefix((PetscObject)distdm,prefix);CHKERRQ(ierr); ierr = DMDestroy(&dm);CHKERRQ(ierr); dm = distdm; } } ierr = PetscLogStagePop();CHKERRQ(ierr); basedm = dm; dm = NULL; for (iter=0 ; iter<max_conv_its ; iter++) { ierr = PetscLogStagePush(stage[6]);CHKERRQ(ierr); /* make new DM */ ierr = DMClone(basedm, &dm);CHKERRQ(ierr); ierr = PetscObjectSetOptionsPrefix((PetscObject) dm, "ex56_");CHKERRQ(ierr); ierr = PetscObjectSetName( (PetscObject)dm,"Mesh");CHKERRQ(ierr); ierr = PetscOptionsClearValue(NULL,"-ex56_dm_refine");CHKERRQ(ierr); ierr = PetscOptionsInsertString(NULL,options[iter]);CHKERRQ(ierr); ierr = DMSetFromOptions(dm);CHKERRQ(ierr); /* refinement done here in Plex, p4est */ /* snes */ ierr = SNESCreate(comm, &snes);CHKERRQ(ierr); ierr = SNESSetDM(snes, dm);CHKERRQ(ierr); /* fem */ { const PetscInt Ncomp = dim; const PetscInt components[] = {0,1,2}; const PetscInt Nfid = 1, Npid = 1; const PetscInt fid[] = {1}; /* The fixed faces (x=0) */ const PetscInt pid[] = {2}; /* The faces with loading (x=L_x) */ PetscFE fe; PetscDS prob; DM cdm = dm; ierr = PetscFECreateDefault(dm, dim, dim, PETSC_FALSE, NULL, PETSC_DECIDE, &fe);CHKERRQ(ierr); /* elasticity */ ierr = PetscObjectSetName((PetscObject) fe, "deformation");CHKERRQ(ierr); /* FEM prob */ ierr = DMGetDS(dm, &prob);CHKERRQ(ierr); ierr = PetscDSSetDiscretization(prob, 0, (PetscObject) fe);CHKERRQ(ierr); /* setup problem */ if (run_type==1) { ierr = PetscDSSetJacobian(prob, 0, 0, NULL, NULL, NULL, g3_uu_3d);CHKERRQ(ierr); ierr = PetscDSSetResidual(prob, 0, f0_u_x4, f1_u_3d);CHKERRQ(ierr); } else { ierr = PetscDSSetJacobian(prob, 0, 0, NULL, NULL, NULL, g3_uu_3d_alpha);CHKERRQ(ierr); ierr = PetscDSSetResidual(prob, 0, f0_u, f1_u_3d_alpha);CHKERRQ(ierr); ierr = PetscDSSetBdResidual(prob, 0, f0_bd_u_3d, f1_bd_u);CHKERRQ(ierr); } /* bcs */ if (run_type==1) { PetscInt id = 1; ierr = DMAddBoundary(dm, DM_BC_ESSENTIAL, "wall", "boundary", 0, 0, NULL, (void (*)()) zero, 1, &id, NULL);CHKERRQ(ierr); } else { ierr = PetscDSAddBoundary(prob, DM_BC_ESSENTIAL, "fixed", "Faces", 0, Ncomp, components, (void (*)()) zero, Nfid, fid, NULL);CHKERRQ(ierr); ierr = PetscDSAddBoundary(prob, DM_BC_NATURAL, "traction", "Faces", 0, Ncomp, components, NULL, Npid, pid, NULL);CHKERRQ(ierr); } while (cdm) { ierr = DMSetDS(cdm,prob);CHKERRQ(ierr); ierr = DMGetCoarseDM(cdm, &cdm);CHKERRQ(ierr); } ierr = PetscFEDestroy(&fe);CHKERRQ(ierr); } /* vecs & mat */ ierr = DMCreateGlobalVector(dm,&xx);CHKERRQ(ierr); ierr = VecDuplicate(xx, &bb);CHKERRQ(ierr); ierr = PetscObjectSetName((PetscObject) bb, "b");CHKERRQ(ierr); ierr = PetscObjectSetName((PetscObject) xx, "u");CHKERRQ(ierr); ierr = DMCreateMatrix(dm, &Amat);CHKERRQ(ierr); ierr = VecGetSize(bb,&N);CHKERRQ(ierr); local_sizes[iter] = N; ierr = PetscPrintf(PETSC_COMM_WORLD,"[%d]%s %d global equations, %d vertices\n",rank,PETSC_FUNCTION_NAME,N,N/dim);CHKERRQ(ierr); if (use_nearnullspace && N/dim > 1) { /* Set up the near null space (a.k.a. rigid body modes) that will be used by the multigrid preconditioner */ DM subdm; MatNullSpace nearNullSpace; PetscInt fields = 0; PetscObject deformation; ierr = DMCreateSubDM(dm, 1, &fields, NULL, &subdm);CHKERRQ(ierr); ierr = DMPlexCreateRigidBody(subdm, &nearNullSpace);CHKERRQ(ierr); ierr = DMGetField(dm, 0, &deformation);CHKERRQ(ierr); ierr = PetscObjectCompose(deformation, "nearnullspace", (PetscObject) nearNullSpace);CHKERRQ(ierr); ierr = DMDestroy(&subdm);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nearNullSpace);CHKERRQ(ierr); /* created by DM and destroyed by Mat */ } ierr = DMPlexSetSNESLocalFEM(dm,NULL,NULL,NULL);CHKERRQ(ierr); ierr = SNESSetJacobian(snes, Amat, Amat, NULL, NULL);CHKERRQ(ierr); ierr = SNESSetFromOptions(snes);CHKERRQ(ierr); ierr = DMSetUp(dm);CHKERRQ(ierr); ierr = PetscLogStagePop();CHKERRQ(ierr); ierr = PetscLogStagePush(stage[0]);CHKERRQ(ierr); /* ksp */ ierr = SNESGetKSP(snes, &ksp);CHKERRQ(ierr); ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr); /* test BCs */ ierr = VecZeroEntries(xx);CHKERRQ(ierr); if (test_nonzero_cols) { if (rank==0) ierr = VecSetValue(xx,0,1.0,INSERT_VALUES);CHKERRQ(ierr); ierr = VecAssemblyBegin(xx);CHKERRQ(ierr); ierr = VecAssemblyEnd(xx);CHKERRQ(ierr); } ierr = VecZeroEntries(bb);CHKERRQ(ierr); ierr = VecGetSize(bb,&i);CHKERRQ(ierr); local_sizes[iter] = i; ierr = PetscPrintf(PETSC_COMM_WORLD,"[%d]%s %d equations in vector, %d vertices\n",rank,PETSC_FUNCTION_NAME,i,i/dim);CHKERRQ(ierr); /* setup solver, dummy solve to really setup */ if (0) { ierr = KSPSetTolerances(ksp,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,1);CHKERRQ(ierr); ierr = SNESSolve(snes, bb, xx);CHKERRQ(ierr); ierr = KSPSetTolerances(ksp,PETSC_DEFAULT,PETSC_DEFAULT,PETSC_DEFAULT,50);CHKERRQ(ierr); ierr = VecZeroEntries(xx);CHKERRQ(ierr); } ierr = PetscLogStagePop();CHKERRQ(ierr); /* solve */ ierr = PetscLogStagePush(stage[1]);CHKERRQ(ierr); ierr = SNESSolve(snes, bb, xx);CHKERRQ(ierr); ierr = PetscLogStagePop();CHKERRQ(ierr); ierr = VecNorm(xx,NORM_INFINITY,&mdisp[iter]);CHKERRQ(ierr); ierr = DMViewFromOptions(dm, NULL, "-dm_view");CHKERRQ(ierr); { PetscViewer viewer = NULL; PetscViewerFormat fmt; ierr = PetscOptionsGetViewer(comm,"ex56_","-vec_view",&viewer,&fmt,&flg);CHKERRQ(ierr); if (flg) { ierr = PetscViewerPushFormat(viewer,fmt);CHKERRQ(ierr); ierr = VecView(xx,viewer);CHKERRQ(ierr); ierr = VecView(bb,viewer);CHKERRQ(ierr); ierr = PetscViewerPopFormat(viewer);CHKERRQ(ierr); } ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr); } /* Free work space */ ierr = DMDestroy(&dm);CHKERRQ(ierr); ierr = SNESDestroy(&snes);CHKERRQ(ierr); ierr = VecDestroy(&xx);CHKERRQ(ierr); ierr = VecDestroy(&bb);CHKERRQ(ierr); ierr = MatDestroy(&Amat);CHKERRQ(ierr); } ierr = DMDestroy(&basedm);CHKERRQ(ierr); if (run_type==1) { err[0] = 59.975208 - mdisp[0]; /* error with what I think is the exact solution */ } else { err[0] = 171.038 - mdisp[0]; } for (iter=1 ; iter<max_conv_its ; iter++) { if (run_type==1) { err[iter] = 59.975208 - mdisp[iter]; } else { err[iter] = 171.038 - mdisp[iter]; } PetscPrintf(PETSC_COMM_WORLD,"[%d]%s %D) N=%12D, max displ=%9.7e, disp diff=%9.2e, error=%4.3e, rate=%3.2g\n", rank,PETSC_FUNCTION_NAME,iter,local_sizes[iter],mdisp[iter], mdisp[iter]-mdisp[iter-1],err[iter],log(err[iter-1]/err[iter])/log(2.)); } ierr = PetscFinalize(); return ierr; }
int main(int argc, char **argv) { SNES snes; /* nonlinear solver */ DM dm; /* problem definition */ Vec u,r; /* solution, residual vectors */ Mat A,J; /* Jacobian matrix */ MatNullSpace nullSpace; /* May be necessary for pressure */ AppCtx user; /* user-defined work context */ JacActionCtx userJ; /* context for Jacobian MF action */ PetscInt its; /* iterations for convergence */ PetscReal error = 0.0; /* L_2 error in the solution */ PetscInt numComponents = 0, f; PetscErrorCode ierr; ierr = PetscInitialize(&argc, &argv, NULL, help);CHKERRQ(ierr); ierr = ProcessOptions(PETSC_COMM_WORLD, &user);CHKERRQ(ierr); ierr = SNESCreate(PETSC_COMM_WORLD, &snes);CHKERRQ(ierr); ierr = CreateMesh(PETSC_COMM_WORLD, &user, &dm);CHKERRQ(ierr); ierr = SNESSetDM(snes, dm);CHKERRQ(ierr); ierr = SetupElement(dm, &user);CHKERRQ(ierr); for (f = 0; f < NUM_FIELDS; ++f) { PetscInt numComp; ierr = PetscFEGetNumComponents(user.fe[f], &numComp);CHKERRQ(ierr); numComponents += numComp; } ierr = PetscMalloc(NUM_FIELDS * sizeof(void (*)(const PetscReal[], PetscScalar *)), &user.exactFuncs);CHKERRQ(ierr); user.fem.bcFuncs = (void (**)(const PetscReal[], PetscScalar *)) user.exactFuncs; ierr = SetupExactSolution(dm, &user);CHKERRQ(ierr); ierr = SetupSection(dm, &user);CHKERRQ(ierr); ierr = DMPlexCreateClosureIndex(dm, NULL);CHKERRQ(ierr); ierr = DMCreateGlobalVector(dm, &u);CHKERRQ(ierr); ierr = VecDuplicate(u, &r);CHKERRQ(ierr); ierr = DMSetMatType(dm,MATAIJ);CHKERRQ(ierr); ierr = DMCreateMatrix(dm, &J);CHKERRQ(ierr); if (user.jacobianMF) { PetscInt M, m, N, n; ierr = MatGetSize(J, &M, &N);CHKERRQ(ierr); ierr = MatGetLocalSize(J, &m, &n);CHKERRQ(ierr); ierr = MatCreate(PETSC_COMM_WORLD, &A);CHKERRQ(ierr); ierr = MatSetSizes(A, m, n, M, N);CHKERRQ(ierr); ierr = MatSetType(A, MATSHELL);CHKERRQ(ierr); ierr = MatSetUp(A);CHKERRQ(ierr); ierr = MatShellSetOperation(A, MATOP_MULT, (void (*)(void))FormJacobianAction);CHKERRQ(ierr); userJ.dm = dm; userJ.J = J; userJ.user = &user; ierr = DMCreateLocalVector(dm, &userJ.u);CHKERRQ(ierr); ierr = DMPlexProjectFunctionLocal(dm, user.fe, user.exactFuncs, INSERT_BC_VALUES, userJ.u);CHKERRQ(ierr); ierr = MatShellSetContext(A, &userJ);CHKERRQ(ierr); } else { A = J; } ierr = CreatePressureNullSpace(dm, &user, &nullSpace);CHKERRQ(ierr); ierr = MatSetNullSpace(J, nullSpace);CHKERRQ(ierr); if (A != J) { ierr = MatSetNullSpace(A, nullSpace);CHKERRQ(ierr); } ierr = DMSNESSetFunctionLocal(dm, (PetscErrorCode (*)(DM,Vec,Vec,void*))DMPlexComputeResidualFEM,&user);CHKERRQ(ierr); ierr = DMSNESSetJacobianLocal(dm, (PetscErrorCode (*)(DM,Vec,Mat,Mat,MatStructure*,void*))DMPlexComputeJacobianFEM,&user);CHKERRQ(ierr); ierr = SNESSetJacobian(snes, A, J, NULL, NULL);CHKERRQ(ierr); ierr = SNESSetFromOptions(snes);CHKERRQ(ierr); ierr = DMPlexProjectFunction(dm, user.fe, user.exactFuncs, INSERT_ALL_VALUES, u);CHKERRQ(ierr); if (user.showInitial) {ierr = DMVecViewLocal(dm, u, PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);} if (user.runType == RUN_FULL) { ierr = DMPlexProjectFunction(dm, user.fe, user.initialGuess, INSERT_VALUES, u);CHKERRQ(ierr); if (user.showInitial) {ierr = DMVecViewLocal(dm, u, PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);} if (user.debug) { ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr); ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); } ierr = SNESSolve(snes, NULL, u);CHKERRQ(ierr); ierr = SNESGetIterationNumber(snes, &its);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "Number of SNES iterations = %D\n", its);CHKERRQ(ierr); ierr = DMPlexComputeL2Diff(dm, user.fe, user.exactFuncs, u, &error);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %.3g\n", error);CHKERRQ(ierr); if (user.showSolution) { ierr = PetscPrintf(PETSC_COMM_WORLD, "Solution\n");CHKERRQ(ierr); ierr = VecChop(u, 3.0e-9);CHKERRQ(ierr); ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); } } else { PetscReal res = 0.0; /* Check discretization error */ ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr); ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); ierr = DMPlexComputeL2Diff(dm, user.fe, user.exactFuncs, u, &error);CHKERRQ(ierr); if (error >= 1.0e-11) { ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %g\n", error);CHKERRQ(ierr); } else { ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: < 1.0e-11\n", error);CHKERRQ(ierr); } /* Check residual */ ierr = SNESComputeFunction(snes, u, r);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial Residual\n");CHKERRQ(ierr); ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr); ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Residual: %g\n", res);CHKERRQ(ierr); /* Check Jacobian */ { Vec b; MatStructure flag; PetscBool isNull; ierr = SNESComputeJacobian(snes, u, &A, &A, &flag);CHKERRQ(ierr); ierr = MatNullSpaceTest(nullSpace, J, &isNull);CHKERRQ(ierr); if (!isNull) SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_PLIB, "The null space calculated for the system operator is invalid."); ierr = VecDuplicate(u, &b);CHKERRQ(ierr); ierr = VecSet(r, 0.0);CHKERRQ(ierr); ierr = SNESComputeFunction(snes, r, b);CHKERRQ(ierr); ierr = MatMult(A, u, r);CHKERRQ(ierr); ierr = VecAXPY(r, 1.0, b);CHKERRQ(ierr); ierr = VecDestroy(&b);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "Au - b = Au + F(0)\n");CHKERRQ(ierr); ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr); ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "Linear L_2 Residual: %g\n", res);CHKERRQ(ierr); } } if (user.runType == RUN_FULL) { PetscViewer viewer; Vec uLocal; const char *name; ierr = PetscViewerCreate(PETSC_COMM_WORLD, &viewer);CHKERRQ(ierr); ierr = PetscViewerSetType(viewer, PETSCVIEWERVTK);CHKERRQ(ierr); ierr = PetscViewerSetFormat(viewer, PETSC_VIEWER_ASCII_VTK);CHKERRQ(ierr); ierr = PetscViewerFileSetName(viewer, "ex62_sol.vtk");CHKERRQ(ierr); ierr = DMGetLocalVector(dm, &uLocal);CHKERRQ(ierr); ierr = PetscObjectGetName((PetscObject) u, &name);CHKERRQ(ierr); ierr = PetscObjectSetName((PetscObject) uLocal, name);CHKERRQ(ierr); ierr = DMGlobalToLocalBegin(dm, u, INSERT_VALUES, uLocal);CHKERRQ(ierr); ierr = DMGlobalToLocalEnd(dm, u, INSERT_VALUES, uLocal);CHKERRQ(ierr); ierr = VecView(uLocal, viewer);CHKERRQ(ierr); ierr = DMRestoreLocalVector(dm, &uLocal);CHKERRQ(ierr); ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr); } ierr = PetscFree(user.exactFuncs);CHKERRQ(ierr); ierr = DestroyElement(&user);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullSpace);CHKERRQ(ierr); if (user.jacobianMF) { ierr = VecDestroy(&userJ.u);CHKERRQ(ierr); } if (A != J) { ierr = MatDestroy(&A);CHKERRQ(ierr); } ierr = MatDestroy(&J);CHKERRQ(ierr); ierr = VecDestroy(&u);CHKERRQ(ierr); ierr = VecDestroy(&r);CHKERRQ(ierr); ierr = SNESDestroy(&snes);CHKERRQ(ierr); ierr = DMDestroy(&dm);CHKERRQ(ierr); ierr = PetscFinalize(); return 0; }
PetscErrorCode computeMatrix2D(KSP ksp, Mat A, Mat pc, MatStructure * matStructure, void* ctx){ PetscUserCtx* context = (PetscUserCtx*) ctx; Parameters & parameters = context -> getParameters(); IntScalarField & flags = context->getFlowField().getFlags(); int *limitsX, *limitsY, *limitsZ; context->getLimits(&limitsX, &limitsY, &limitsZ); PetscScalar dx = parameters.geometry.dx, dy = parameters.geometry.dy; PetscScalar stencilValues[5]; MatStencil row, column[5]; PetscInt i, j, Nx, Ny; Nx = parameters.geometry.sizeX + 2; Ny = parameters.geometry.sizeY + 2; // Loop for inner nodes for (j = limitsY[0]; j < limitsY[1]; j++){ for (i = limitsX[0]; i < limitsX[1]; i++){ row.i = i; row.j = j; const int obstacle = flags.getValue(i-limitsX[0]+2, j-limitsY[0]+2); if ((obstacle & OBSTACLE_SELF) == 0) { // If we have a fluid cell // Definition of values stencilValues[0] = 1/(dx*dx); stencilValues[1] = 1/(dx*dx); stencilValues[2] = -(2.0/(dx*dx) + 2.0/(dy*dy)); stencilValues[3] = 1/(dy*dy); stencilValues[4] = 1/(dy*dy); // Definition of positions. Order must correspond to values column[0].i = i+1; column[0].j = j; column[1].i = i-1; column[1].j = j; column[2].i = i; column[2].j = j; column[3].i = i; column[3].j = j+1; column[4].i = i; column[4].j = j-1; MatSetValuesStencil(A, 1, &row, 5, column, stencilValues, INSERT_VALUES); } else if (obstacle != OBSTACLE_SELF + OBSTACLE_LEFT + OBSTACLE_RIGHT + OBSTACLE_TOP + OBSTACLE_BOTTOM) { // Not fluid, but fluid somewhere around int counter = 0; // This will contain how many neighbours are fluid if ((obstacle & OBSTACLE_LEFT) == 0){ // If there is fluid to the left stencilValues[counter] = 1.0; column[counter].i = i-1; column[counter].j = j; counter++; // We have just identified a fuid cell and prepared to average } if ((obstacle & OBSTACLE_RIGHT) == 0){ stencilValues[counter] = 1.0; column[counter].i = i+1; column[counter].j = j; counter++; } if ((obstacle & OBSTACLE_BOTTOM) == 0){ stencilValues[counter] = 1.0; column[counter].i = i; column[counter].j = j-1; counter++; } if ((obstacle & OBSTACLE_TOP) == 0){ stencilValues[counter] = 1.0; column[counter].i = i; column[counter].j = j+1; counter++; } // A column for the cell itself stencilValues[counter] = (double)(-counter); column[counter].i = i; column[counter].j = j; // Once we identified how many fluid cells are around and set columns for each, we // enter the row into the matrix. MatSetValuesStencil(A, 1, &row, counter+1, column, stencilValues, INSERT_VALUES); } else { // The remaining possibility is that the cell is obstacle surrounded // by more obstacle cells // Here, we just add an equation to set the value according to the right hand side stencilValues[0] = 1.0; column[0].i = i; column[0].j = j; MatSetValuesStencil(A, 1, &row, 1, column, stencilValues, INSERT_VALUES); } } } // Left wall if (context->setAsBoundary & LEFT_WALL_BIT){ for (j = limitsY[0]; j < limitsY[1]; j++){ column[0].i = 0; column[0].j = j; column[1].i = context->displacement[0]; column[1].j = j; row.i = 0; row.j = j; if (parameters.walls.typeLeft == DIRICHLET){ // If Dirichlet velocity boundary conditions // therefore, Neumann in the pressure stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeLeft == NEUMANN){ // Neumann velocity boundary conditions, stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } // Right wall if (context->setAsBoundary & RIGHT_WALL_BIT){ for (j = limitsY[0]; j < limitsY[1]; j++){ column[0].i = Nx-1; column[0].j = j; column[1].i = context->displacement[1]; column[1].j = j; row.i = Nx-1; row.j = j; if (parameters.walls.typeRight == DIRICHLET){ stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeRight == NEUMANN){ stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } // Bottom wall if (context->setAsBoundary & BOTTOM_WALL_BIT){ for (i = limitsX[0]; i < limitsX[1]; i++){ column[0].i = i; column[0].j = 0; column[1].i = i; column[1].j = context->displacement[2]; row.i = i; row.j = 0; if (parameters.walls.typeBottom == DIRICHLET){ stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeBottom == NEUMANN) { stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } // Top wall if (context->setAsBoundary & TOP_WALL_BIT){ for (i = limitsX[0]; i < limitsX[1]; i++){ column[0].i = i; column[0].j = Ny-1; column[1].i = i; column[1].j = context->displacement[3]; row.i = i; row.j = Ny-1; if (parameters.walls.typeTop == DIRICHLET){ stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeTop == NEUMANN) { stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY); MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY); MatNullSpace nullspace; MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace); MatSetNullSpace(A,nullspace); MatNullSpaceDestroy(&nullspace); return 0; }
PetscErrorCode PCBDDCNullSpaceAdaptGlobal(PC pc) { PC_IS* pcis = (PC_IS*)(pc->data); PC_BDDC* pcbddc = (PC_BDDC*)(pc->data); KSP inv_change; const Vec *nsp_vecs; Vec *new_nsp_vecs; PetscInt i,nsp_size,new_nsp_size,start_new; PetscBool nsp_has_cnst; MatNullSpace new_nsp; PetscErrorCode ierr; PetscFunctionBegin; /* create KSP for change of basis */ ierr = MatGetSize(pcbddc->ChangeOfBasisMatrix,&i,NULL);CHKERRQ(ierr); ierr = KSPCreate(PetscObjectComm((PetscObject)pc),&inv_change);CHKERRQ(ierr); ierr = KSPSetErrorIfNotConverged(inv_change,pc->erroriffailure);CHKERRQ(ierr); ierr = KSPSetOperators(inv_change,pcbddc->ChangeOfBasisMatrix,pcbddc->ChangeOfBasisMatrix);CHKERRQ(ierr); ierr = KSPSetTolerances(inv_change,1.e-8,1.e-8,PETSC_DEFAULT,2*i);CHKERRQ(ierr); if (pcbddc->dbg_flag) { ierr = KSPMonitorSet(inv_change,KSPMonitorDefault,pcbddc->dbg_viewer,NULL);CHKERRQ(ierr); } ierr = KSPSetUp(inv_change);CHKERRQ(ierr); /* get nullspace and transform it */ ierr = MatNullSpaceGetVecs(pcbddc->NullSpace,&nsp_has_cnst,&nsp_size,&nsp_vecs);CHKERRQ(ierr); new_nsp_size = nsp_size; if (nsp_has_cnst) { new_nsp_size++; } ierr = VecDuplicateVecs(pcis->vec1_global,new_nsp_size,&new_nsp_vecs);CHKERRQ(ierr); start_new = 0; if (nsp_has_cnst) { start_new = 1; ierr = VecSet(new_nsp_vecs[0],1.0);CHKERRQ(ierr); if (pcbddc->dbg_flag) { ierr = PetscViewerFlush(pcbddc->dbg_viewer);CHKERRQ(ierr); ierr = PetscViewerASCIIPrintf(pcbddc->dbg_viewer,"Mapping constant in nullspace\n");CHKERRQ(ierr); } ierr = KSPSolve(inv_change,new_nsp_vecs[0],new_nsp_vecs[0]);CHKERRQ(ierr); } for (i=0;i<nsp_size;i++) { ierr = PetscViewerFlush(pcbddc->dbg_viewer);CHKERRQ(ierr); ierr = PetscViewerASCIIPrintf(pcbddc->dbg_viewer,"Mapping %dth vector in nullspace\n",i);CHKERRQ(ierr); ierr = KSPSolve(inv_change,nsp_vecs[i],new_nsp_vecs[i+start_new]);CHKERRQ(ierr); } ierr = PCBDDCOrthonormalizeVecs(new_nsp_size,new_nsp_vecs);CHKERRQ(ierr); ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject)pc),PETSC_FALSE,new_nsp_size,new_nsp_vecs,&new_nsp);CHKERRQ(ierr); ierr = PCBDDCSetNullSpace(pc,new_nsp);CHKERRQ(ierr); /* free */ ierr = KSPDestroy(&inv_change);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&new_nsp);CHKERRQ(ierr); ierr = VecDestroyVecs(new_nsp_size,&new_nsp_vecs);CHKERRQ(ierr); /* check */ if (pcbddc->dbg_flag) { PetscBool nsp_t=PETSC_FALSE; Mat temp_mat; Mat_IS* matis = (Mat_IS*)pc->pmat->data; temp_mat = matis->A; matis->A = pcbddc->local_mat; pcbddc->local_mat = temp_mat; ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr); ierr = PetscPrintf(PetscObjectComm((PetscObject)(pc->pmat)),"Check nullspace with change of basis: %d\n",nsp_t);CHKERRQ(ierr); temp_mat = matis->A; matis->A = pcbddc->local_mat; pcbddc->local_mat = temp_mat; } PetscFunctionReturn(0); }
int main(int argc,char **argv) { SNES snes; /* SNES context */ Mat J; /* Jacobian matrix */ DM da; Vec x,r; /* vectors */ PetscErrorCode ierr; PetscInt N = 5; MatNullSpace constants; ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr; ierr = PetscOptionsGetInt(NULL,NULL,"-n",&N,NULL);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create nonlinear solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = SNESCreate(PETSC_COMM_WORLD,&snes);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create vector data structures; set function evaluation routine - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /* Create distributed array (DMDA) to manage parallel grid and vectors */ ierr = DMDACreate1d(PETSC_COMM_WORLD,DM_BOUNDARY_PERIODIC,N,1,1,NULL,&da);CHKERRQ(ierr); ierr = DMSetFromOptions(da);CHKERRQ(ierr); ierr = DMSetUp(da);CHKERRQ(ierr); /* Extract global and local vectors from DMDA; then duplicate for remaining vectors that are the same types */ ierr = DMCreateGlobalVector(da,&x);CHKERRQ(ierr); ierr = VecDuplicate(x,&r);CHKERRQ(ierr); /* Set function evaluation routine and vector. Whenever the nonlinear solver needs to compute the nonlinear function, it will call this routine. - Note that the final routine argument is the user-defined context that provides application-specific data for the function evaluation routine. */ ierr = SNESSetFunction(snes,r,FormFunction,da);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create matrix data structure; set Jacobian evaluation routine - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateMatrix(da,&J);CHKERRQ(ierr); ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&constants);CHKERRQ(ierr); ierr = MatSetNullSpace(J,constants);CHKERRQ(ierr); ierr = SNESSetJacobian(snes,J,J,FormJacobian,da);CHKERRQ(ierr); ierr = SNESSetFromOptions(snes);CHKERRQ(ierr); ierr = SNESSolve(snes,NULL,x);CHKERRQ(ierr); ierr = VecDestroy(&x);CHKERRQ(ierr); ierr = VecDestroy(&r);CHKERRQ(ierr); ierr = MatDestroy(&J);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&constants);CHKERRQ(ierr); ierr = SNESDestroy(&snes);CHKERRQ(ierr); ierr = DMDestroy(&da);CHKERRQ(ierr); ierr = PetscFinalize(); return ierr; }
PetscErrorCode computeMatrix3D(KSP ksp, Mat A, Mat pc, MatStructure * matStructure, void* ctx){ PetscUserCtx* context = (PetscUserCtx*) ctx; Parameters & parameters = context -> getParameters(); IntScalarField & flags = context->getFlowField().getFlags(); int *limitsX, *limitsY, *limitsZ; context->getLimits(&limitsX, &limitsY, &limitsZ); PetscScalar dx = parameters.geometry.dx, dy = parameters.geometry.dy, dz = parameters.geometry.dz; PetscScalar stencilValues[7]; MatStencil row, column[7]; PetscInt i, j, k, Nx, Ny, Nz; Nx = parameters.geometry.sizeX + 2; Ny = parameters.geometry.sizeY + 2; Nz = parameters.geometry.sizeZ + 2; // Loop for inner nodes for (k = limitsZ[0]; k < limitsZ[1]; k++){ for (j = limitsY[0]; j < limitsY[1]; j++){ for (i = limitsX[0]; i < limitsX[1]; i++){ row.i = i; row.j = j, row.k = k; const int obstacle = flags.getValue(i-limitsX[0]+2, j-limitsY[0]+2, k-limitsZ[0]+2); if ((obstacle & OBSTACLE_SELF) == 0) { // If the cell is fluid // Definition of values stencilValues[0] = 1/(dx*dx); stencilValues[1] = 1/(dx*dx); stencilValues[2] = 1/(dy*dy); stencilValues[3] = 1/(dy*dy); stencilValues[4] = 1/(dz*dz); stencilValues[5] = 1/(dz*dz); stencilValues[6] = -(2.0/(dx*dx) + 2.0/(dy*dy) + 2.0/(dz*dz)); // Definition of positions. Order must correspond to values column[0].i = i+1; column[0].j = j; column[0].k = k; column[1].i = i-1; column[1].j = j; column[1].k = k; column[2].i = i; column[2].j = j+1; column[2].k = k; column[3].i = i; column[3].j = j-1; column[3].k = k; column[4].i = i; column[4].j = j; column[4].k = k+1; column[5].i = i; column[5].j = j; column[5].k = k-1; column[6].i = i; column[6].j = j; column[6].k = k; MatSetValuesStencil(A, 1, &row, 7, column, stencilValues, INSERT_VALUES); } else if (obstacle != 127) { // If non-fluid and still not completely surounded int counter = 0; if ((obstacle & OBSTACLE_LEFT) == 0){ // If there's fluid to the left stencilValues[counter] = 1; column[counter].i = i-1; column[counter].j = j, column[counter].k = k; counter++; } if ((obstacle & OBSTACLE_RIGHT) == 0){ stencilValues[counter] = 1; column[counter].i = i+1; column[counter].j = j, column[counter].k = k; counter++; } if ((obstacle & OBSTACLE_BOTTOM) == 0){ stencilValues[counter] = 1; column[counter].i = i; column[counter].j = j-1, column[counter].k = k; counter++; } if ((obstacle & OBSTACLE_TOP) == 0){ stencilValues[counter] = 1; column[counter].i = i; column[counter].j = j+1, column[counter].k = k; counter++; } if ((obstacle & OBSTACLE_FRONT) == 0){ stencilValues[counter] = 1; column[counter].i = i; column[counter].j = j, column[counter].k = k-1; counter++; } if ((obstacle & OBSTACLE_BACK) == 0){ stencilValues[counter] = 1; column[counter].i = i; column[counter].j = j, column[counter].k = k+1; counter++; } // Now set a line for the element itself stencilValues[counter] = (double)(-counter); column[counter].i = i; column[counter].j = j, column[counter].k = k; MatSetValuesStencil(A, 1, &row, counter+1, column, stencilValues, INSERT_VALUES); } else { // If the cell is an inner obstacle cell stencilValues[0] = 1.0; column[0].i = i; column[0].j = j; column[0].k = k; MatSetValuesStencil(A, 1, &row, 1, column, stencilValues, INSERT_VALUES); } } } } // Left wall if (context->setAsBoundary & LEFT_WALL_BIT){ for (j = limitsY[0]; j < limitsY[1]; j++){ for (k = limitsZ[0]; k < limitsZ[1]; k++){ column[0].i = 0; column[0].j = j; column[0].k = k; column[1].i = context->displacement[0]; column[1].j = j; column[1].k = k; row.i = 0; row.j = j; row.k = k; if (parameters.walls.typeLeft == DIRICHLET){ stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeLeft == NEUMANN){ stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } } // Right wall if (context->setAsBoundary & RIGHT_WALL_BIT){ for (j = limitsY[0]; j < limitsY[1]; j++){ for (k = limitsZ[0]; k < limitsZ[1]; k++){ column[0].i = Nx-1; column[0].j = j; column[0].k = k; column[1].i = context->displacement[1]; column[1].j = j; column[1].k = k; row.i = Nx-1; row.j = j; row.k = k; if (parameters.walls.typeRight == DIRICHLET){ stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeRight == NEUMANN){ stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } } // Bottom wall if (context->setAsBoundary & BOTTOM_WALL_BIT){ for (i = limitsX[0]; i < limitsX[1]; i++){ for (k = limitsZ[0]; k < limitsZ[1]; k++){ column[0].i = i; column[0].j = 0; column[0].k = k; column[1].i = i; column[1].j = context->displacement[2]; column[1].k = k; row.i = i; row.j = 0; row.k = k; if (parameters.walls.typeBottom == DIRICHLET){ stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeBottom == NEUMANN){ stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } } // Top wall if (context->setAsBoundary & TOP_WALL_BIT){ for (i = limitsX[0]; i < limitsX[1]; i++){ for (k = limitsZ[0]; k < limitsZ[1]; k++){ column[0].i = i; column[0].j = Ny-1; column[0].k = k; column[1].i = i; column[1].j = context->displacement[3]; column[1].k = k; row.i = i; row.j = Ny-1; row.k = k; if (parameters.walls.typeTop == DIRICHLET){ stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeTop == NEUMANN){ stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } } // Front wall if (context->setAsBoundary & FRONT_WALL_BIT){ for (i = limitsX[0]; i < limitsX[1]; i++){ for (j = limitsY[0]; j < limitsY[1]; j++){ column[0].i = i; column[0].j = j; column[0].k = 0; column[1].i = i; column[1].j = j; column[1].k = context->displacement[4]; row.i = i; row.j = j; row.k = 0; if (parameters.walls.typeFront == DIRICHLET){ stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeFront == NEUMANN){ stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } } // Back wall if (context->setAsBoundary & BACK_WALL_BIT){ for (i = limitsX[0]; i < limitsX[1]; i++){ for (j = limitsY[0]; j < limitsY[1]; j++){ column[0].i = i; column[0].j = j; column[0].k = Nz-1; column[1].i = i; column[1].j = j; column[1].k = context->displacement[5]; row.i = i; row.j = j; row.k = Nz-1; if (parameters.walls.typeBack == DIRICHLET){ stencilValues[0] = 1; stencilValues[1] = -1; } else if (parameters.walls.typeBack == NEUMANN){ stencilValues[0] = 0.5; stencilValues[1] = 0.5; } MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES); } } } MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY); MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY); MatNullSpace nullspace; MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace); MatSetNullSpace(A,nullspace); MatNullSpaceDestroy(&nullspace); return 0; }
int main(int argc, char **argv) { SNES snes; /* nonlinear solver */ Vec u,r; /* solution, residual vectors */ Mat A,J; /* Jacobian matrix */ MatNullSpace nullSpace; /* May be necessary for pressure */ AppCtx user; /* user-defined work context */ JacActionCtx userJ; /* context for Jacobian MF action */ PetscInt its; /* iterations for convergence */ PetscReal error = 0.0; /* L_2 error in the solution */ const PetscInt numComponents = NUM_BASIS_COMPONENTS_TOTAL; PetscErrorCode ierr; ierr = PetscInitialize(&argc, &argv, NULL, help);CHKERRQ(ierr); ierr = ProcessOptions(PETSC_COMM_WORLD, &user);CHKERRQ(ierr); ierr = SNESCreate(PETSC_COMM_WORLD, &snes);CHKERRQ(ierr); ierr = CreateMesh(PETSC_COMM_WORLD, &user, &user.dm);CHKERRQ(ierr); ierr = SNESSetDM(snes, user.dm);CHKERRQ(ierr); ierr = SetupExactSolution(user.dm, &user);CHKERRQ(ierr); ierr = SetupQuadrature(&user);CHKERRQ(ierr); ierr = SetupSection(user.dm, &user);CHKERRQ(ierr); ierr = DMCreateGlobalVector(user.dm, &u);CHKERRQ(ierr); ierr = VecDuplicate(u, &r);CHKERRQ(ierr); ierr = DMCreateMatrix(user.dm, MATAIJ, &J);CHKERRQ(ierr); if (user.jacobianMF) { PetscInt M, m, N, n; ierr = MatGetSize(J, &M, &N);CHKERRQ(ierr); ierr = MatGetLocalSize(J, &m, &n);CHKERRQ(ierr); ierr = MatCreate(PETSC_COMM_WORLD, &A);CHKERRQ(ierr); ierr = MatSetSizes(A, m, n, M, N);CHKERRQ(ierr); ierr = MatSetType(A, MATSHELL);CHKERRQ(ierr); ierr = MatSetUp(A);CHKERRQ(ierr); ierr = MatShellSetOperation(A, MATOP_MULT, (void (*)(void))FormJacobianAction);CHKERRQ(ierr); userJ.dm = user.dm; userJ.J = J; userJ.user = &user; ierr = DMCreateLocalVector(user.dm, &userJ.u);CHKERRQ(ierr); ierr = DMPlexProjectFunctionLocal(user.dm, numComponents, user.exactFuncs, INSERT_BC_VALUES, userJ.u);CHKERRQ(ierr); ierr = MatShellSetContext(A, &userJ);CHKERRQ(ierr); } else { A = J; } ierr = CreatePressureNullSpace(user.dm, &user, &nullSpace);CHKERRQ(ierr); ierr = MatSetNullSpace(J, nullSpace);CHKERRQ(ierr); if (A != J) { ierr = MatSetNullSpace(A, nullSpace);CHKERRQ(ierr); } ierr = DMSNESSetFunctionLocal(user.dm, (PetscErrorCode (*)(DM,Vec,Vec,void*))DMPlexComputeResidualFEM,&user);CHKERRQ(ierr); ierr = DMSNESSetJacobianLocal(user.dm, (PetscErrorCode (*)(DM,Vec,Mat,Mat,MatStructure*,void*))DMPlexComputeJacobianFEM,&user);CHKERRQ(ierr); ierr = SNESSetJacobian(snes, A, J, NULL, NULL);CHKERRQ(ierr); ierr = SNESSetFromOptions(snes);CHKERRQ(ierr); ierr = DMPlexProjectFunction(user.dm, numComponents, user.exactFuncs, INSERT_ALL_VALUES, u);CHKERRQ(ierr); if (user.showInitial) {ierr = DMVecViewLocal(user.dm, u, PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);} if (user.runType == RUN_FULL) { PetscScalar (*initialGuess[numComponents])(const PetscReal x[]); PetscInt c; for (c = 0; c < numComponents; ++c) initialGuess[c] = zero; ierr = DMPlexProjectFunction(user.dm, numComponents, initialGuess, INSERT_VALUES, u);CHKERRQ(ierr); if (user.showInitial) {ierr = DMVecViewLocal(user.dm, u, PETSC_VIEWER_STDOUT_SELF);CHKERRQ(ierr);} if (user.debug) { ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr); ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); } ierr = SNESSolve(snes, NULL, u);CHKERRQ(ierr); ierr = SNESGetIterationNumber(snes, &its);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "Number of SNES iterations = %D\n", its);CHKERRQ(ierr); ierr = DMPlexComputeL2Diff(user.dm, user.fem.quad, user.exactFuncs, u, &error);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %.3g\n", error);CHKERRQ(ierr); if (user.showSolution) { ierr = PetscPrintf(PETSC_COMM_WORLD, "Solution\n");CHKERRQ(ierr); ierr = VecChop(u, 3.0e-9);CHKERRQ(ierr); ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); } } else { PetscReal res = 0.0; /* Check discretization error */ ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial guess\n");CHKERRQ(ierr); ierr = VecView(u, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); ierr = DMPlexComputeL2Diff(user.dm, user.fem.quad, user.exactFuncs, u, &error);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Error: %g\n", error);CHKERRQ(ierr); /* Check residual */ ierr = SNESComputeFunction(snes, u, r);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "Initial Residual\n");CHKERRQ(ierr); ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr); ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "L_2 Residual: %g\n", res);CHKERRQ(ierr); /* Check Jacobian */ { Vec b; MatStructure flag; PetscBool isNull; ierr = SNESComputeJacobian(snes, u, &A, &A, &flag);CHKERRQ(ierr); ierr = MatNullSpaceTest(nullSpace, J, &isNull);CHKERRQ(ierr); if (!isNull) SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_PLIB, "The null space calculated for the system operator is invalid."); ierr = VecDuplicate(u, &b);CHKERRQ(ierr); ierr = VecSet(r, 0.0);CHKERRQ(ierr); ierr = SNESComputeFunction(snes, r, b);CHKERRQ(ierr); ierr = MatMult(A, u, r);CHKERRQ(ierr); ierr = VecAXPY(r, 1.0, b);CHKERRQ(ierr); ierr = VecDestroy(&b);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "Au - b = Au + F(0)\n");CHKERRQ(ierr); ierr = VecChop(r, 1.0e-10);CHKERRQ(ierr); ierr = VecView(r, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); ierr = VecNorm(r, NORM_2, &res);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD, "Linear L_2 Residual: %g\n", res);CHKERRQ(ierr); } } if (user.runType == RUN_FULL) { PetscViewer viewer; Vec uLocal; ierr = PetscViewerCreate(PETSC_COMM_WORLD, &viewer);CHKERRQ(ierr); ierr = PetscViewerSetType(viewer, PETSCVIEWERVTK);CHKERRQ(ierr); ierr = PetscViewerSetFormat(viewer, PETSC_VIEWER_ASCII_VTK);CHKERRQ(ierr); ierr = PetscViewerFileSetName(viewer, "ex62_sol.vtk");CHKERRQ(ierr); ierr = DMGetLocalVector(user.dm, &uLocal);CHKERRQ(ierr); ierr = DMGlobalToLocalBegin(user.dm, u, INSERT_VALUES, uLocal);CHKERRQ(ierr); ierr = DMGlobalToLocalEnd(user.dm, u, INSERT_VALUES, uLocal);CHKERRQ(ierr); ierr = PetscObjectReference((PetscObject) user.dm);CHKERRQ(ierr); /* Needed because viewer destroys the DM */ ierr = PetscObjectReference((PetscObject) uLocal);CHKERRQ(ierr); /* Needed because viewer destroys the Vec */ ierr = PetscViewerVTKAddField(viewer, (PetscObject) user.dm, DMPlexVTKWriteAll, PETSC_VTK_POINT_FIELD, (PetscObject) uLocal);CHKERRQ(ierr); ierr = DMRestoreLocalVector(user.dm, &uLocal);CHKERRQ(ierr); ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr); } ierr = DestroyQuadrature(&user);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullSpace);CHKERRQ(ierr); if (user.jacobianMF) { ierr = VecDestroy(&userJ.u);CHKERRQ(ierr); } if (A != J) { ierr = MatDestroy(&A);CHKERRQ(ierr); } ierr = MatDestroy(&J);CHKERRQ(ierr); ierr = VecDestroy(&u);CHKERRQ(ierr); ierr = VecDestroy(&r);CHKERRQ(ierr); ierr = SNESDestroy(&snes);CHKERRQ(ierr); ierr = DMDestroy(&user.dm);CHKERRQ(ierr); ierr = PetscFinalize(); return 0; }
PetscErrorCode PCBDDCNullSpaceAdaptGlobal(PC pc) { PC_IS* pcis = (PC_IS*) (pc->data); PC_BDDC* pcbddc = (PC_BDDC*)(pc->data); KSP inv_change; PC pc_change; const Vec *nsp_vecs; Vec *new_nsp_vecs; PetscInt i,nsp_size,new_nsp_size,start_new; PetscBool nsp_has_cnst; MatNullSpace new_nsp; PetscErrorCode ierr; MPI_Comm comm; PetscFunctionBegin; /* create KSP for change of basis */ ierr = KSPCreate(PETSC_COMM_SELF,&inv_change);CHKERRQ(ierr); ierr = KSPSetOperators(inv_change,pcbddc->ChangeOfBasisMatrix,pcbddc->ChangeOfBasisMatrix,SAME_PRECONDITIONER);CHKERRQ(ierr); ierr = KSPSetType(inv_change,KSPPREONLY);CHKERRQ(ierr); ierr = KSPGetPC(inv_change,&pc_change);CHKERRQ(ierr); ierr = PCSetType(pc_change,PCLU);CHKERRQ(ierr); ierr = KSPSetUp(inv_change);CHKERRQ(ierr); /* get nullspace and transform it */ ierr = MatNullSpaceGetVecs(pcbddc->NullSpace,&nsp_has_cnst,&nsp_size,&nsp_vecs);CHKERRQ(ierr); new_nsp_size = nsp_size; if (nsp_has_cnst) { new_nsp_size++; } ierr = PetscMalloc(new_nsp_size*sizeof(Vec),&new_nsp_vecs);CHKERRQ(ierr); for (i=0;i<new_nsp_size;i++) { ierr = VecDuplicate(pcis->vec1_global,&new_nsp_vecs[i]);CHKERRQ(ierr); } start_new = 0; if (nsp_has_cnst) { start_new = 1; ierr = VecSet(new_nsp_vecs[0],1.0);CHKERRQ(ierr); ierr = VecSet(pcis->vec1_B,1.0);CHKERRQ(ierr); ierr = KSPSolve(inv_change,pcis->vec1_B,pcis->vec1_B); ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,new_nsp_vecs[0],INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); ierr = VecScatterEnd (pcis->global_to_B,pcis->vec1_B,new_nsp_vecs[0],INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); } for (i=0;i<nsp_size;i++) { ierr = VecCopy(nsp_vecs[i],new_nsp_vecs[i+start_new]);CHKERRQ(ierr); ierr = VecScatterBegin(pcis->global_to_B,nsp_vecs[i],pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); ierr = VecScatterEnd (pcis->global_to_B,nsp_vecs[i],pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr); ierr = KSPSolve(inv_change,pcis->vec1_B,pcis->vec1_B); ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,new_nsp_vecs[i+start_new],INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); ierr = VecScatterEnd (pcis->global_to_B,pcis->vec1_B,new_nsp_vecs[i+start_new],INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr); } ierr = PCBDDCOrthonormalizeVecs(new_nsp_size,new_nsp_vecs);CHKERRQ(ierr); #if 0 PetscBool nsp_t=PETSC_FALSE; ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr); printf("Original Null Space test: %d\n",nsp_t); Mat temp_mat; Mat_IS* matis = (Mat_IS*)pc->pmat->data; temp_mat = matis->A; matis->A = pcbddc->local_mat; pcbddc->local_mat = temp_mat; ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr); printf("Original Null Space, mat changed test: %d\n",nsp_t); { PetscReal test_norm; for (i=0;i<new_nsp_size;i++) { ierr = MatMult(pc->pmat,new_nsp_vecs[i],pcis->vec1_global);CHKERRQ(ierr); ierr = VecNorm(pcis->vec1_global,NORM_2,&test_norm);CHKERRQ(ierr); if (test_norm > 1.e-12) { printf("------------ERROR VEC %d------------------\n",i); ierr = VecView(pcis->vec1_global,PETSC_VIEWER_STDOUT_WORLD); printf("------------------------------------------\n"); } } } #endif ierr = KSPDestroy(&inv_change);CHKERRQ(ierr); ierr = PetscObjectGetComm((PetscObject)pc,&comm);CHKERRQ(ierr); ierr = MatNullSpaceCreate(comm,PETSC_FALSE,new_nsp_size,new_nsp_vecs,&new_nsp);CHKERRQ(ierr); ierr = PCBDDCSetNullSpace(pc,new_nsp);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&new_nsp);CHKERRQ(ierr); #if 0 ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr); printf("New Null Space, mat changed: %d\n",nsp_t); temp_mat = matis->A; matis->A = pcbddc->local_mat; pcbddc->local_mat = temp_mat; ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr); printf("New Null Space, mat original: %d\n",nsp_t); #endif for (i=0;i<new_nsp_size;i++) { ierr = VecDestroy(&new_nsp_vecs[i]);CHKERRQ(ierr); } ierr = PetscFree(new_nsp_vecs);CHKERRQ(ierr); PetscFunctionReturn(0); }
std::pair<unsigned int, Real> PetscNonlinearSolver<T>::solve (SparseMatrix<T>& jac_in, // System Jacobian Matrix NumericVector<T>& x_in, // Solution vector NumericVector<T>& r_in, // Residual vector const double, // Stopping tolerance const unsigned int) { START_LOG("solve()", "PetscNonlinearSolver"); this->init (); // Make sure the data passed in are really of Petsc types PetscMatrix<T>* jac = libmesh_cast_ptr<PetscMatrix<T>*>(&jac_in); PetscVector<T>* x = libmesh_cast_ptr<PetscVector<T>*>(&x_in); PetscVector<T>* r = libmesh_cast_ptr<PetscVector<T>*>(&r_in); PetscErrorCode ierr=0; PetscInt n_iterations =0; // Should actually be a PetscReal, but I don't know which version of PETSc first introduced PetscReal Real final_residual_norm=0.; ierr = SNESSetFunction (_snes, r->vec(), __libmesh_petsc_snes_residual, this); LIBMESH_CHKERRABORT(ierr); // Only set the jacobian function if we've been provided with something to call. // This allows a user to set their own jacobian function if they want to if (this->jacobian || this->jacobian_object || this->residual_and_jacobian_object) { ierr = SNESSetJacobian (_snes, jac->mat(), jac->mat(), __libmesh_petsc_snes_jacobian, this); LIBMESH_CHKERRABORT(ierr); } #if !PETSC_VERSION_LESS_THAN(3,3,0) // Only set the nullspace if we have a way of computing it and the result is non-empty. if (this->nullspace || this->nullspace_object) { MatNullSpace msp; this->build_mat_null_space(this->nullspace_object, this->nullspace, &msp); if (msp) { ierr = MatSetNullSpace(jac->mat(), msp); LIBMESH_CHKERRABORT(ierr); ierr = MatNullSpaceDestroy(&msp); LIBMESH_CHKERRABORT(ierr); } } // Only set the nearnullspace if we have a way of computing it and the result is non-empty. if (this->nearnullspace || this->nearnullspace_object) { MatNullSpace msp = PETSC_NULL; this->build_mat_null_space(this->nearnullspace_object, this->nearnullspace, &msp); if(msp) { ierr = MatSetNearNullSpace(jac->mat(), msp); LIBMESH_CHKERRABORT(ierr); ierr = MatNullSpaceDestroy(&msp); LIBMESH_CHKERRABORT(ierr); } } #endif // Have the Krylov subspace method use our good initial guess rather than 0 KSP ksp; ierr = SNESGetKSP (_snes, &ksp); LIBMESH_CHKERRABORT(ierr); // Set the tolerances for the iterative solver. Use the user-supplied // tolerance for the relative residual & leave the others at default values ierr = KSPSetTolerances (ksp, this->initial_linear_tolerance, PETSC_DEFAULT, PETSC_DEFAULT, this->max_linear_iterations); LIBMESH_CHKERRABORT(ierr); // Set the tolerances for the non-linear solver. ierr = SNESSetTolerances(_snes, this->absolute_residual_tolerance, this->relative_residual_tolerance, this->relative_step_tolerance, this->max_nonlinear_iterations, this->max_function_evaluations); LIBMESH_CHKERRABORT(ierr); //Pull in command-line options KSPSetFromOptions(ksp); SNESSetFromOptions(_snes); if (this->user_presolve) this->user_presolve(this->system()); //Set the preconditioning matrix if(this->_preconditioner) { this->_preconditioner->set_matrix(jac_in); this->_preconditioner->init(); } // ierr = KSPSetInitialGuessNonzero (ksp, PETSC_TRUE); // LIBMESH_CHKERRABORT(ierr); // Older versions (at least up to 2.1.5) of SNESSolve took 3 arguments, // the last one being a pointer to an int to hold the number of iterations required. # if PETSC_VERSION_LESS_THAN(2,2,0) ierr = SNESSolve (_snes, x->vec(), &n_iterations); LIBMESH_CHKERRABORT(ierr); // 2.2.x style #elif PETSC_VERSION_LESS_THAN(2,3,0) ierr = SNESSolve (_snes, x->vec()); LIBMESH_CHKERRABORT(ierr); // 2.3.x & newer style #else ierr = SNESSolve (_snes, PETSC_NULL, x->vec()); LIBMESH_CHKERRABORT(ierr); ierr = SNESGetIterationNumber(_snes,&n_iterations); LIBMESH_CHKERRABORT(ierr); ierr = SNESGetLinearSolveIterations(_snes, &_n_linear_iterations); LIBMESH_CHKERRABORT(ierr); ierr = SNESGetFunctionNorm(_snes,&final_residual_norm); LIBMESH_CHKERRABORT(ierr); #endif // Get and store the reason for convergence SNESGetConvergedReason(_snes, &_reason); //Based on Petsc 2.3.3 documentation all diverged reasons are negative this->converged = (_reason >= 0); this->clear(); STOP_LOG("solve()", "PetscNonlinearSolver"); // return the # of its. and the final residual norm. return std::make_pair(n_iterations, final_residual_norm); }
/* This assumes that the DM has been cloned prior to the call */ PetscErrorCode DMCreateSubDM_Section_Private(DM dm, PetscInt numFields, PetscInt fields[], IS *is, DM *subdm) { PetscSection section, sectionGlobal; PetscInt *subIndices; PetscInt subSize = 0, subOff = 0, nF, f, pStart, pEnd, p; PetscErrorCode ierr; PetscFunctionBegin; if (!numFields) PetscFunctionReturn(0); ierr = DMGetDefaultSection(dm, §ion);CHKERRQ(ierr); ierr = DMGetDefaultGlobalSection(dm, §ionGlobal);CHKERRQ(ierr); if (!section) SETERRQ(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "Must set default section for DM before splitting fields"); if (!sectionGlobal) SETERRQ(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "Must set default global section for DM before splitting fields"); ierr = PetscSectionGetNumFields(section, &nF);CHKERRQ(ierr); if (numFields > nF) SETERRQ2(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "Number of requested fields %d greater than number of DM fields %d", numFields, nF); if (is) { ierr = PetscSectionGetChart(sectionGlobal, &pStart, &pEnd);CHKERRQ(ierr); for (p = pStart; p < pEnd; ++p) { PetscInt gdof; ierr = PetscSectionGetDof(sectionGlobal, p, &gdof);CHKERRQ(ierr); if (gdof > 0) { for (f = 0; f < numFields; ++f) { PetscInt fdof, fcdof; ierr = PetscSectionGetFieldDof(section, p, fields[f], &fdof);CHKERRQ(ierr); ierr = PetscSectionGetFieldConstraintDof(section, p, fields[f], &fcdof);CHKERRQ(ierr); subSize += fdof-fcdof; } } } ierr = PetscMalloc1(subSize, &subIndices);CHKERRQ(ierr); for (p = pStart; p < pEnd; ++p) { PetscInt gdof, goff; ierr = PetscSectionGetDof(sectionGlobal, p, &gdof);CHKERRQ(ierr); if (gdof > 0) { ierr = PetscSectionGetOffset(sectionGlobal, p, &goff);CHKERRQ(ierr); for (f = 0; f < numFields; ++f) { PetscInt fdof, fcdof, fc, f2, poff = 0; /* Can get rid of this loop by storing field information in the global section */ for (f2 = 0; f2 < fields[f]; ++f2) { ierr = PetscSectionGetFieldDof(section, p, f2, &fdof);CHKERRQ(ierr); ierr = PetscSectionGetFieldConstraintDof(section, p, f2, &fcdof);CHKERRQ(ierr); poff += fdof-fcdof; } ierr = PetscSectionGetFieldDof(section, p, fields[f], &fdof);CHKERRQ(ierr); ierr = PetscSectionGetFieldConstraintDof(section, p, fields[f], &fcdof);CHKERRQ(ierr); for (fc = 0; fc < fdof-fcdof; ++fc, ++subOff) { subIndices[subOff] = goff+poff+fc; } } } } ierr = ISCreateGeneral(PetscObjectComm((PetscObject)dm), subSize, subIndices, PETSC_OWN_POINTER, is);CHKERRQ(ierr); } if (subdm) { PetscSection subsection; PetscBool haveNull = PETSC_FALSE; PetscInt f, nf = 0; ierr = PetscSectionCreateSubsection(section, numFields, fields, &subsection);CHKERRQ(ierr); ierr = DMSetDefaultSection(*subdm, subsection);CHKERRQ(ierr); ierr = PetscSectionDestroy(&subsection);CHKERRQ(ierr); for (f = 0; f < numFields; ++f) { (*subdm)->nullspaceConstructors[f] = dm->nullspaceConstructors[fields[f]]; if ((*subdm)->nullspaceConstructors[f]) { haveNull = PETSC_TRUE; nf = f; } } if (haveNull) { MatNullSpace nullSpace; ierr = (*(*subdm)->nullspaceConstructors[nf])(*subdm, nf, &nullSpace);CHKERRQ(ierr); ierr = PetscObjectCompose((PetscObject) *is, "nullspace", (PetscObject) nullSpace);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullSpace);CHKERRQ(ierr); } if (dm->fields) { if (nF != dm->numFields) SETERRQ2(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "The number of DM fields %d does not match the number of Section fields %d", dm->numFields, nF); ierr = DMSetNumFields(*subdm, numFields);CHKERRQ(ierr); for (f = 0; f < numFields; ++f) { ierr = PetscObjectListDuplicate(dm->fields[fields[f]]->olist, &(*subdm)->fields[f]->olist);CHKERRQ(ierr); } if (numFields == 1) { MatNullSpace space; Mat pmat; ierr = PetscObjectQuery((*subdm)->fields[0], "nullspace", (PetscObject*) &space);CHKERRQ(ierr); if (space) {ierr = PetscObjectCompose((PetscObject) *is, "nullspace", (PetscObject) space);CHKERRQ(ierr);} ierr = PetscObjectQuery((*subdm)->fields[0], "nearnullspace", (PetscObject*) &space);CHKERRQ(ierr); if (space) {ierr = PetscObjectCompose((PetscObject) *is, "nearnullspace", (PetscObject) space);CHKERRQ(ierr);} ierr = PetscObjectQuery((*subdm)->fields[0], "pmat", (PetscObject*) &pmat);CHKERRQ(ierr); if (pmat) {ierr = PetscObjectCompose((PetscObject) *is, "pmat", (PetscObject) pmat);CHKERRQ(ierr);} } } } PetscFunctionReturn(0); }
PetscErrorCode ComputeMatrix(KSP ksp, Mat J,Mat jac, void *ctx) { PetscErrorCode ierr; PetscInt i,j,k,mx,my,mz,xm,ym,zm,xs,ys,zs,num, numi, numj, numk; PetscScalar v[7],Hx,Hy,Hz,HyHzdHx,HxHzdHy,HxHydHz; MatStencil row, col[7]; DM da; MatNullSpace nullspace; PetscFunctionBeginUser; ierr = KSPGetDM(ksp,&da);CHKERRQ(ierr); ierr = DMDAGetInfo(da,0,&mx,&my,&mz,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr); Hx = 1.0 / (PetscReal)(mx); Hy = 1.0 / (PetscReal)(my); Hz = 1.0 / (PetscReal)(mz); HyHzdHx = Hy*Hz/Hx; HxHzdHy = Hx*Hz/Hy; HxHydHz = Hx*Hy/Hz; ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr); for (k=zs; k<zs+zm; k++) { for (j=ys; j<ys+ym; j++) { for (i=xs; i<xs+xm; i++) { row.i = i; row.j = j; row.k = k; if (i==0 || j==0 || k==0 || i==mx-1 || j==my-1 || k==mz-1) { num = 0; numi=0; numj=0; numk=0; if (k!=0) { v[num] = -HxHydHz; col[num].i = i; col[num].j = j; col[num].k = k-1; num++; numk++; } if (j!=0) { v[num] = -HxHzdHy; col[num].i = i; col[num].j = j-1; col[num].k = k; num++; numj++; } if (i!=0) { v[num] = -HyHzdHx; col[num].i = i-1; col[num].j = j; col[num].k = k; num++; numi++; } if (i!=mx-1) { v[num] = -HyHzdHx; col[num].i = i+1; col[num].j = j; col[num].k = k; num++; numi++; } if (j!=my-1) { v[num] = -HxHzdHy; col[num].i = i; col[num].j = j+1; col[num].k = k; num++; numj++; } if (k!=mz-1) { v[num] = -HxHydHz; col[num].i = i; col[num].j = j; col[num].k = k+1; num++; numk++; } v[num] = (PetscReal)(numk)*HxHydHz + (PetscReal)(numj)*HxHzdHy + (PetscReal)(numi)*HyHzdHx; col[num].i = i; col[num].j = j; col[num].k = k; num++; ierr = MatSetValuesStencil(jac,1,&row,num,col,v,INSERT_VALUES);CHKERRQ(ierr); } else { v[0] = -HxHydHz; col[0].i = i; col[0].j = j; col[0].k = k-1; v[1] = -HxHzdHy; col[1].i = i; col[1].j = j-1; col[1].k = k; v[2] = -HyHzdHx; col[2].i = i-1; col[2].j = j; col[2].k = k; v[3] = 2.0*(HyHzdHx + HxHzdHy + HxHydHz); col[3].i = i; col[3].j = j; col[3].k = k; v[4] = -HyHzdHx; col[4].i = i+1; col[4].j = j; col[4].k = k; v[5] = -HxHzdHy; col[5].i = i; col[5].j = j+1; col[5].k = k; v[6] = -HxHydHz; col[6].i = i; col[6].j = j; col[6].k = k+1; ierr = MatSetValuesStencil(jac,1,&row,7,col,v,INSERT_VALUES);CHKERRQ(ierr); } } } } ierr = MatAssemblyBegin(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); ierr = MatAssemblyEnd(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);CHKERRQ(ierr); ierr = MatSetNullSpace(jac,nullspace);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullspace);CHKERRQ(ierr); PetscFunctionReturn(0); }
int main(int argc,char **args) { PetscErrorCode ierr; Mat C; PetscMPIInt rank,size; PetscInt i,m = 5,N,start,end,M; PetscInt idx[4]; PetscScalar Ke[16]; PetscReal h; Vec u,b; KSP ksp; MatNullSpace nullsp; ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; ierr = PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL);CHKERRQ(ierr); N = (m+1)*(m+1); /* dimension of matrix */ M = m*m; /* number of elements */ h = 1.0/m; /* mesh width */ ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr); ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr); /* Create stiffness matrix */ ierr = MatCreate(PETSC_COMM_WORLD,&C);CHKERRQ(ierr); ierr = MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,N,N);CHKERRQ(ierr); ierr = MatSetFromOptions(C);CHKERRQ(ierr); ierr = MatSetUp(C);CHKERRQ(ierr); start = rank*(M/size) + ((M%size) < rank ? (M%size) : rank); end = start + M/size + ((M%size) > rank); /* Assemble matrix */ ierr = FormElementStiffness(h*h,Ke);CHKERRQ(ierr); /* element stiffness for Laplacian */ for (i=start; i<end; i++) { /* location of lower left corner of element */ /* node numbers for the four corners of element */ idx[0] = (m+1)*(i/m) + (i % m); idx[1] = idx[0]+1; idx[2] = idx[1] + m + 1; idx[3] = idx[2] - 1; ierr = MatSetValues(C,4,idx,4,idx,Ke,ADD_VALUES);CHKERRQ(ierr); } ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr); /* Create right-hand-side and solution vectors */ ierr = VecCreate(PETSC_COMM_WORLD,&u);CHKERRQ(ierr); ierr = VecSetSizes(u,PETSC_DECIDE,N);CHKERRQ(ierr); ierr = VecSetFromOptions(u);CHKERRQ(ierr); ierr = PetscObjectSetName((PetscObject)u,"Approx. Solution");CHKERRQ(ierr); ierr = VecDuplicate(u,&b);CHKERRQ(ierr); ierr = PetscObjectSetName((PetscObject)b,"Right hand side");CHKERRQ(ierr); ierr = VecSet(b,1.0);CHKERRQ(ierr); ierr = VecSetValue(b,0,1.2,ADD_VALUES);CHKERRQ(ierr); ierr = VecSet(u,0.0);CHKERRQ(ierr); /* Solve linear system */ ierr = KSPCreate(PETSC_COMM_WORLD,&ksp);CHKERRQ(ierr); ierr = KSPSetOperators(ksp,C,C);CHKERRQ(ierr); ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr); ierr = KSPSetInitialGuessNonzero(ksp,PETSC_TRUE);CHKERRQ(ierr); ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&nullsp);CHKERRQ(ierr); /* The KSP solver will remove this nullspace from the solution at each iteration */ ierr = MatSetNullSpace(C,nullsp);CHKERRQ(ierr); /* The KSP solver will remove from the right hand side any portion in this nullspace, thus making the linear system consistent. */ ierr = MatSetTransposeNullSpace(C,nullsp);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullsp);CHKERRQ(ierr); ierr = KSPSolve(ksp,b,u);CHKERRQ(ierr); /* Free work space */ ierr = KSPDestroy(&ksp);CHKERRQ(ierr); ierr = VecDestroy(&u);CHKERRQ(ierr); ierr = VecDestroy(&b);CHKERRQ(ierr); ierr = MatDestroy(&C);CHKERRQ(ierr); ierr = PetscFinalize(); return ierr; }
int main(int argc,char **argv) { AppCtx appctx; /* user-defined application context */ PetscErrorCode ierr; PetscInt i, xs, xm, ind, j, lenglob; PetscReal x, *wrk_ptr1, *wrk_ptr2; MatNullSpace nsp; PetscMPIInt size; /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Initialize program and set problem parameters - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ PetscFunctionBegin; ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr; /*initialize parameters */ appctx.param.N = 10; /* order of the spectral element */ appctx.param.E = 10; /* number of elements */ appctx.param.L = 4.0; /* length of the domain */ appctx.param.mu = 0.01; /* diffusion coefficient */ appctx.initial_dt = 5e-3; appctx.param.steps = PETSC_MAX_INT; appctx.param.Tend = 4; ierr = PetscOptionsGetInt(NULL,NULL,"-N",&appctx.param.N,NULL);CHKERRQ(ierr); ierr = PetscOptionsGetInt(NULL,NULL,"-E",&appctx.param.E,NULL);CHKERRQ(ierr); ierr = PetscOptionsGetReal(NULL,NULL,"-Tend",&appctx.param.Tend,NULL);CHKERRQ(ierr); ierr = PetscOptionsGetReal(NULL,NULL,"-mu",&appctx.param.mu,NULL);CHKERRQ(ierr); appctx.param.Le = appctx.param.L/appctx.param.E; ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr); if (appctx.param.E % size) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_ARG_WRONG,"Number of elements must be divisible by number of processes"); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create GLL data structures - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = PetscGLLCreate(appctx.param.N,PETSCGLL_VIA_LINEARALGEBRA,&appctx.SEMop.gll);CHKERRQ(ierr); lenglob = appctx.param.E*(appctx.param.N-1); /* Create distributed array (DMDA) to manage parallel grid and vectors and to set up the ghost point communication pattern. There are E*(Nl-1)+1 total grid values spread equally among all the processors, except first and last */ ierr = DMDACreate1d(PETSC_COMM_WORLD,DM_BOUNDARY_PERIODIC,lenglob,1,1,NULL,&appctx.da);CHKERRQ(ierr); ierr = DMSetFromOptions(appctx.da);CHKERRQ(ierr); ierr = DMSetUp(appctx.da);CHKERRQ(ierr); /* Extract global and local vectors from DMDA; we use these to store the approximate solution. Then duplicate these for remaining vectors that have the same types. */ ierr = DMCreateGlobalVector(appctx.da,&appctx.dat.curr_sol);CHKERRQ(ierr); ierr = VecDuplicate(appctx.dat.curr_sol,&appctx.SEMop.grid);CHKERRQ(ierr); ierr = VecDuplicate(appctx.dat.curr_sol,&appctx.SEMop.mass);CHKERRQ(ierr); ierr = DMDAGetCorners(appctx.da,&xs,NULL,NULL,&xm,NULL,NULL);CHKERRQ(ierr); ierr = DMDAVecGetArray(appctx.da,appctx.SEMop.grid,&wrk_ptr1);CHKERRQ(ierr); ierr = DMDAVecGetArray(appctx.da,appctx.SEMop.mass,&wrk_ptr2);CHKERRQ(ierr); /* Compute function over the locally owned part of the grid */ xs=xs/(appctx.param.N-1); xm=xm/(appctx.param.N-1); /* Build total grid and mass over entire mesh (multi-elemental) */ for (i=xs; i<xs+xm; i++) { for (j=0; j<appctx.param.N-1; j++) { x = (appctx.param.Le/2.0)*(appctx.SEMop.gll.nodes[j]+1.0)+appctx.param.Le*i; ind=i*(appctx.param.N-1)+j; wrk_ptr1[ind]=x; wrk_ptr2[ind]=.5*appctx.param.Le*appctx.SEMop.gll.weights[j]; if (j==0) wrk_ptr2[ind]+=.5*appctx.param.Le*appctx.SEMop.gll.weights[j]; } } ierr = DMDAVecRestoreArray(appctx.da,appctx.SEMop.grid,&wrk_ptr1);CHKERRQ(ierr); ierr = DMDAVecRestoreArray(appctx.da,appctx.SEMop.mass,&wrk_ptr2);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create matrix data structure; set matrix evaluation routine. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMSetMatrixPreallocateOnly(appctx.da, PETSC_TRUE);CHKERRQ(ierr); ierr = DMCreateMatrix(appctx.da,&appctx.SEMop.stiff);CHKERRQ(ierr); ierr = DMCreateMatrix(appctx.da,&appctx.SEMop.grad);CHKERRQ(ierr); /* For linear problems with a time-dependent f(u,t) in the equation u_t = f(u,t), the user provides the discretized right-hand-side as a time-dependent matrix. */ ierr = RHSMatrixLaplaciangllDM(appctx.ts,0.0,appctx.dat.curr_sol,appctx.SEMop.stiff,appctx.SEMop.stiff,&appctx);CHKERRQ(ierr); ierr = RHSMatrixAdvectiongllDM(appctx.ts,0.0,appctx.dat.curr_sol,appctx.SEMop.grad,appctx.SEMop.grad,&appctx);CHKERRQ(ierr); /* For linear problems with a time-dependent f(u,t) in the equation u_t = f(u,t), the user provides the discretized right-hand-side as a time-dependent matrix. */ ierr = MatDuplicate(appctx.SEMop.stiff,MAT_COPY_VALUES,&appctx.SEMop.keptstiff);CHKERRQ(ierr); /* attach the null space to the matrix, this probably is not needed but does no harm */ ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&nsp);CHKERRQ(ierr); ierr = MatSetNullSpace(appctx.SEMop.stiff,nsp);CHKERRQ(ierr); ierr = MatSetNullSpace(appctx.SEMop.keptstiff,nsp);CHKERRQ(ierr); ierr = MatNullSpaceTest(nsp,appctx.SEMop.stiff,NULL);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr); /* attach the null space to the matrix, this probably is not needed but does no harm */ ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&nsp);CHKERRQ(ierr); ierr = MatSetNullSpace(appctx.SEMop.grad,nsp);CHKERRQ(ierr); ierr = MatNullSpaceTest(nsp,appctx.SEMop.grad,NULL);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr); /* Create the TS solver that solves the ODE and its adjoint; set its options */ ierr = TSCreate(PETSC_COMM_WORLD,&appctx.ts);CHKERRQ(ierr); ierr = TSSetProblemType(appctx.ts,TS_NONLINEAR);CHKERRQ(ierr); ierr = TSSetType(appctx.ts,TSRK);CHKERRQ(ierr); ierr = TSSetDM(appctx.ts,appctx.da);CHKERRQ(ierr); ierr = TSSetTime(appctx.ts,0.0);CHKERRQ(ierr); ierr = TSSetTimeStep(appctx.ts,appctx.initial_dt);CHKERRQ(ierr); ierr = TSSetMaxSteps(appctx.ts,appctx.param.steps);CHKERRQ(ierr); ierr = TSSetMaxTime(appctx.ts,appctx.param.Tend);CHKERRQ(ierr); ierr = TSSetExactFinalTime(appctx.ts,TS_EXACTFINALTIME_MATCHSTEP);CHKERRQ(ierr); ierr = TSSetTolerances(appctx.ts,1e-7,NULL,1e-7,NULL);CHKERRQ(ierr); ierr = TSSetSaveTrajectory(appctx.ts);CHKERRQ(ierr); ierr = TSSetFromOptions(appctx.ts);CHKERRQ(ierr); ierr = TSSetRHSFunction(appctx.ts,NULL,RHSFunction,&appctx);CHKERRQ(ierr); ierr = TSSetRHSJacobian(appctx.ts,appctx.SEMop.stiff,appctx.SEMop.stiff,RHSJacobian,&appctx);CHKERRQ(ierr); /* Set Initial conditions for the problem */ ierr = TrueSolution(appctx.ts,0,appctx.dat.curr_sol,&appctx);CHKERRQ(ierr); ierr = TSSetSolutionFunction(appctx.ts,(PetscErrorCode (*)(TS,PetscReal,Vec,void *))TrueSolution,&appctx);CHKERRQ(ierr); ierr = TSSetTime(appctx.ts,0.0);CHKERRQ(ierr); ierr = TSSetStepNumber(appctx.ts,0);CHKERRQ(ierr); ierr = TSSolve(appctx.ts,appctx.dat.curr_sol);CHKERRQ(ierr); ierr = MatDestroy(&appctx.SEMop.stiff);CHKERRQ(ierr); ierr = MatDestroy(&appctx.SEMop.keptstiff);CHKERRQ(ierr); ierr = MatDestroy(&appctx.SEMop.grad);CHKERRQ(ierr); ierr = VecDestroy(&appctx.SEMop.grid);CHKERRQ(ierr); ierr = VecDestroy(&appctx.SEMop.mass);CHKERRQ(ierr); ierr = VecDestroy(&appctx.dat.curr_sol);CHKERRQ(ierr); ierr = PetscGLLDestroy(&appctx.SEMop.gll);CHKERRQ(ierr); ierr = DMDestroy(&appctx.da);CHKERRQ(ierr); ierr = TSDestroy(&appctx.ts);CHKERRQ(ierr); /* Always call PetscFinalize() before exiting a program. This routine - finalizes the PETSc libraries as well as MPI - provides summary and diagnostic information if certain runtime options are chosen (e.g., -log_summary). */ ierr = PetscFinalize(); return ierr; }
/* This assumes that the DM has been cloned prior to the call */ PetscErrorCode DMCreateSubDM_Section_Private(DM dm, PetscInt numFields, PetscInt fields[], IS *is, DM *subdm) { PetscSection section, sectionGlobal; PetscInt *subIndices; PetscInt subSize = 0, subOff = 0, nF, f, pStart, pEnd, p; PetscErrorCode ierr; PetscFunctionBegin; if (!numFields) PetscFunctionReturn(0); ierr = DMGetDefaultSection(dm, §ion);CHKERRQ(ierr); ierr = DMGetDefaultGlobalSection(dm, §ionGlobal);CHKERRQ(ierr); if (!section) SETERRQ(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "Must set default section for DM before splitting fields"); if (!sectionGlobal) SETERRQ(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "Must set default global section for DM before splitting fields"); ierr = PetscSectionGetNumFields(section, &nF);CHKERRQ(ierr); if (numFields > nF) SETERRQ2(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "Number of requested fields %d greater than number of DM fields %d", numFields, nF); if (is) { ierr = PetscSectionGetChart(sectionGlobal, &pStart, &pEnd);CHKERRQ(ierr); for (p = pStart; p < pEnd; ++p) { PetscInt gdof; ierr = PetscSectionGetDof(sectionGlobal, p, &gdof);CHKERRQ(ierr); if (gdof > 0) { for (f = 0; f < numFields; ++f) { PetscInt fdof, fcdof; ierr = PetscSectionGetFieldDof(section, p, fields[f], &fdof);CHKERRQ(ierr); ierr = PetscSectionGetFieldConstraintDof(section, p, fields[f], &fcdof);CHKERRQ(ierr); subSize += fdof-fcdof; } } } ierr = PetscMalloc1(subSize, &subIndices);CHKERRQ(ierr); for (p = pStart; p < pEnd; ++p) { PetscInt gdof, goff; ierr = PetscSectionGetDof(sectionGlobal, p, &gdof);CHKERRQ(ierr); if (gdof > 0) { ierr = PetscSectionGetOffset(sectionGlobal, p, &goff);CHKERRQ(ierr); for (f = 0; f < numFields; ++f) { PetscInt fdof, fcdof, fc, f2, poff = 0; /* Can get rid of this loop by storing field information in the global section */ for (f2 = 0; f2 < fields[f]; ++f2) { ierr = PetscSectionGetFieldDof(section, p, f2, &fdof);CHKERRQ(ierr); ierr = PetscSectionGetFieldConstraintDof(section, p, f2, &fcdof);CHKERRQ(ierr); poff += fdof-fcdof; } ierr = PetscSectionGetFieldDof(section, p, fields[f], &fdof);CHKERRQ(ierr); ierr = PetscSectionGetFieldConstraintDof(section, p, fields[f], &fcdof);CHKERRQ(ierr); for (fc = 0; fc < fdof-fcdof; ++fc, ++subOff) { subIndices[subOff] = goff+poff+fc; } } } } ierr = ISCreateGeneral(PetscObjectComm((PetscObject)dm), subSize, subIndices, PETSC_OWN_POINTER, is);CHKERRQ(ierr); } if (subdm) { PetscSection subsection; PetscBool haveNull = PETSC_FALSE; PetscInt f, nf = 0; ierr = PetscSectionCreateSubsection(section, numFields, fields, &subsection);CHKERRQ(ierr); ierr = DMSetDefaultSection(*subdm, subsection);CHKERRQ(ierr); ierr = PetscSectionDestroy(&subsection);CHKERRQ(ierr); for (f = 0; f < numFields; ++f) { (*subdm)->nullspaceConstructors[f] = dm->nullspaceConstructors[fields[f]]; if ((*subdm)->nullspaceConstructors[f]) { haveNull = PETSC_TRUE; nf = f; } } if (haveNull && is) { MatNullSpace nullSpace; ierr = (*(*subdm)->nullspaceConstructors[nf])(*subdm, nf, &nullSpace);CHKERRQ(ierr); ierr = PetscObjectCompose((PetscObject) *is, "nullspace", (PetscObject) nullSpace);CHKERRQ(ierr); ierr = MatNullSpaceDestroy(&nullSpace);CHKERRQ(ierr); } if (dm->prob) { PetscInt Nf; ierr = PetscDSGetNumFields(dm->prob, &Nf);CHKERRQ(ierr); if (nF != Nf) SETERRQ2(PetscObjectComm((PetscObject)dm), PETSC_ERR_ARG_WRONG, "The number of DM fields %d does not match the number of Section fields %d", Nf, nF); ierr = DMSetNumFields(*subdm, numFields);CHKERRQ(ierr); for (f = 0; f < numFields; ++f) { PetscObject disc; ierr = DMGetField(dm, fields[f], &disc);CHKERRQ(ierr); ierr = DMSetField(*subdm, f, disc);CHKERRQ(ierr); } if (numFields == 1 && is) { PetscObject disc, space, pmat; ierr = DMGetField(*subdm, 0, &disc);CHKERRQ(ierr); ierr = PetscObjectQuery(disc, "nullspace", &space);CHKERRQ(ierr); if (space) {ierr = PetscObjectCompose((PetscObject) *is, "nullspace", space);CHKERRQ(ierr);} ierr = PetscObjectQuery(disc, "nearnullspace", &space);CHKERRQ(ierr); if (space) {ierr = PetscObjectCompose((PetscObject) *is, "nearnullspace", space);CHKERRQ(ierr);} ierr = PetscObjectQuery(disc, "pmat", &pmat);CHKERRQ(ierr); if (pmat) {ierr = PetscObjectCompose((PetscObject) *is, "pmat", pmat);CHKERRQ(ierr);} } } } #if 0 /* We need a way to filter the original SF for given fields: - Keeping the original section around it too much I think - We could keep the distributed section, and subset it */ if (dm->sfNatural) { PetscSF sfNatural; ierr = PetscSectionCreateSubsection(dm->originalSection, numFields, fields, &(*subdm)->originalSection);CHKERRQ(ierr); ierr = DMPlexCreateGlobalToNaturalPetscSF(*subdm, &sfNatural);CHKERRQ(ierr); ierr = DMPlexSetGlobalToNaturalPetscSF(*subdm, sfNatural);CHKERRQ(ierr); } #endif PetscFunctionReturn(0); }