static PetscErrorCode PCSetUp_LSC(PC pc)
{
PC_LSC *lsc = (PC_LSC*)pc->data;
Mat L,Lp,B,C;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = PCLSCAllocate_Private(pc);CHKERRQ(ierr);
ierr = PetscObjectQuery((PetscObject)pc->mat,"LSC_L",(PetscObject*)&L);CHKERRQ(ierr);
if (!L) {ierr = PetscObjectQuery((PetscObject)pc->pmat,"LSC_L",(PetscObject*)&L);CHKERRQ(ierr);}
ierr = PetscObjectQuery((PetscObject)pc->pmat,"LSC_Lp",(PetscObject*)&Lp);CHKERRQ(ierr);
if (!Lp) {ierr = PetscObjectQuery((PetscObject)pc->mat,"LSC_Lp",(PetscObject*)&Lp);CHKERRQ(ierr);}
if (!L) {
ierr = MatSchurComplementGetSubMatrices(pc->mat,NULL,NULL,&B,&C,NULL);CHKERRQ(ierr);
if (!lsc->L) {
ierr = MatMatMult(C,B,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&lsc->L);CHKERRQ(ierr);
} else {
ierr = MatMatMult(C,B,MAT_REUSE_MATRIX,PETSC_DEFAULT,&lsc->L);CHKERRQ(ierr);
}
Lp = L = lsc->L;
}
if (lsc->scale) {
Mat Ap;
ierr = MatSchurComplementGetSubMatrices(pc->mat,NULL,&Ap,NULL,NULL,NULL);CHKERRQ(ierr);
ierr = MatGetDiagonal(Ap,lsc->scale);CHKERRQ(ierr); /* Should be the mass matrix, but we don't have plumbing for that yet */
ierr = VecReciprocal(lsc->scale);CHKERRQ(ierr);
}
ierr = KSPSetOperators(lsc->kspL,L,Lp);CHKERRQ(ierr);
ierr = KSPSetFromOptions(lsc->kspL);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
/*@
MatSchurComplementComputeExplicitOperator - Compute the Schur complement matrix explicitly
Collective on Mat
Input Parameter:
. M - the matrix obtained with MatCreateSchurComplement()
Output Parameter:
. S - the Schur complement matrix
Note: This can be expensive, so it is mainly for testing
Level: advanced
.seealso: MatCreateSchurComplement(), MatSchurComplementUpdate()
@*/
PetscErrorCode MatSchurComplementComputeExplicitOperator(Mat M, Mat *S)
{
Mat B, C, D;
KSP ksp;
PC pc;
PetscBool isLU, isILU;
PetscReal fill = 2.0;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = MatSchurComplementGetSubMatrices(M, NULL, NULL, &B, &C, &D);CHKERRQ(ierr);
ierr = MatSchurComplementGetKSP(M, &ksp);CHKERRQ(ierr);
ierr = KSPGetPC(ksp, &pc);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject) pc, PCLU, &isLU);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject) pc, PCILU, &isILU);CHKERRQ(ierr);
if (isLU || isILU) {
Mat fact, Bd, AinvB, AinvBd;
PetscReal eps = 1.0e-10;
/* This can be sped up for banded LU */
ierr = KSPSetUp(ksp);CHKERRQ(ierr);
ierr = PCFactorGetMatrix(pc, &fact);CHKERRQ(ierr);
ierr = MatConvert(B, MATDENSE, MAT_INITIAL_MATRIX, &Bd);CHKERRQ(ierr);
ierr = MatDuplicate(Bd, MAT_DO_NOT_COPY_VALUES, &AinvBd);CHKERRQ(ierr);
ierr = MatMatSolve(fact, Bd, AinvBd);CHKERRQ(ierr);
ierr = MatDestroy(&Bd);CHKERRQ(ierr);
ierr = MatChop(AinvBd, eps);CHKERRQ(ierr);
ierr = MatConvert(AinvBd, MATAIJ, MAT_INITIAL_MATRIX, &AinvB);CHKERRQ(ierr);
ierr = MatDestroy(&AinvBd);CHKERRQ(ierr);
ierr = MatMatMult(C, AinvB, MAT_INITIAL_MATRIX, fill, S);CHKERRQ(ierr);
ierr = MatDestroy(&AinvB);CHKERRQ(ierr);
} else {
Mat Ainvd, Ainv;
ierr = PCComputeExplicitOperator(pc, &Ainvd);CHKERRQ(ierr);
ierr = MatConvert(Ainvd, MATAIJ, MAT_INITIAL_MATRIX, &Ainv);CHKERRQ(ierr);
ierr = MatDestroy(&Ainvd);CHKERRQ(ierr);
#if 0
/* Symmetric version */
ierr = MatPtAP(Ainv, B, MAT_INITIAL_MATRIX, fill, S);CHKERRQ(ierr);
#else
/* Nonsymmetric version */
ierr = MatMatMatMult(C, Ainv, B, MAT_INITIAL_MATRIX, fill, S);CHKERRQ(ierr);
#endif
ierr = MatDestroy(&Ainv);CHKERRQ(ierr);
}
ierr = PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_INFO);CHKERRQ(ierr);
ierr = MatView(*S, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
ierr = PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
if (D) {
MatInfo info;
ierr = MatGetInfo(D, MAT_GLOBAL_SUM, &info);CHKERRQ(ierr);
if (info.nz_used) SETERRQ(PetscObjectComm((PetscObject) M), PETSC_ERR_SUP, "Not yet implemented");
}
PetscFunctionReturn(0);
}
/*@
MatSchurComplementComputeExplicitOperator - Compute the Schur complement matrix explicitly
Collective on Mat
Input Parameter:
. M - the matrix obtained with MatCreateSchurComplement()
Output Parameter:
. S - the Schur complement matrix
Note: This can be expensive, so it is mainly for testing
Level: advanced
.seealso: MatCreateSchurComplement(), MatSchurComplementUpdate()
@*/
PetscErrorCode MatSchurComplementComputeExplicitOperator(Mat M, Mat *S)
{
Mat B, C, D;
KSP ksp;
PC pc;
PetscBool isLU, isILU;
PetscReal fill = 2.0;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = MatSchurComplementGetSubMatrices(M, NULL, NULL, &B, &C, &D);CHKERRQ(ierr);
ierr = MatSchurComplementGetKSP(M, &ksp);CHKERRQ(ierr);
ierr = KSPGetPC(ksp, &pc);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject) pc, PCLU, &isLU);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject) pc, PCILU, &isILU);CHKERRQ(ierr);
if (isLU || isILU) {
Mat fact, Bd, AinvB, AinvBd;
PetscReal eps = 1.0e-10;
/* This can be sped up for banded LU */
ierr = KSPSetUp(ksp);CHKERRQ(ierr);
ierr = PCFactorGetMatrix(pc, &fact);CHKERRQ(ierr);
ierr = MatConvert(B, MATDENSE, MAT_INITIAL_MATRIX, &Bd);CHKERRQ(ierr);
ierr = MatDuplicate(Bd, MAT_DO_NOT_COPY_VALUES, &AinvBd);CHKERRQ(ierr);
ierr = MatMatSolve(fact, Bd, AinvBd);CHKERRQ(ierr);
ierr = MatDestroy(&Bd);CHKERRQ(ierr);
ierr = MatChop(AinvBd, eps);CHKERRQ(ierr);
ierr = MatConvert(AinvBd, MATAIJ, MAT_INITIAL_MATRIX, &AinvB);CHKERRQ(ierr);
ierr = MatDestroy(&AinvBd);CHKERRQ(ierr);
ierr = MatMatMult(C, AinvB, MAT_INITIAL_MATRIX, fill, S);CHKERRQ(ierr);
ierr = MatDestroy(&AinvB);CHKERRQ(ierr);
} else {
Mat Ainvd, Ainv;
ierr = PCComputeExplicitOperator(pc, &Ainvd);CHKERRQ(ierr);
ierr = MatConvert(Ainvd, MATAIJ, MAT_INITIAL_MATRIX, &Ainv);CHKERRQ(ierr);
ierr = MatDestroy(&Ainvd);CHKERRQ(ierr);
#if 0
/* Symmetric version */
ierr = MatPtAP(Ainv, B, MAT_INITIAL_MATRIX, fill, S);CHKERRQ(ierr);
#else
/* Nonsymmetric version */
ierr = MatMatMatMult(C, Ainv, B, MAT_INITIAL_MATRIX, fill, S);CHKERRQ(ierr);
#endif
ierr = MatDestroy(&Ainv);CHKERRQ(ierr);
}
if (D) {
ierr = MatAXPY(*S, -1.0, D, DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
}
ierr = MatScale(*S,-1.0);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PetscErrorCode MatSchurComplementGetPmat_Basic(Mat S,MatReuse preuse,Mat *Spmat)
{
Mat A,B,C,D;
Mat_SchurComplement *schur = (Mat_SchurComplement *)S->data;
PetscErrorCode ierr;
PetscFunctionBegin;
if (preuse == MAT_IGNORE_MATRIX) PetscFunctionReturn(0);
ierr = MatSchurComplementGetSubMatrices(S,&A,NULL,&B,&C,&D);CHKERRQ(ierr);
if (!A) SETERRQ(PetscObjectComm((PetscObject)S),PETSC_ERR_ARG_WRONGSTATE,"Schur complement component matrices unset");
ierr = MatCreateSchurComplementPmat(A,B,C,D,schur->ainvtype,preuse,Spmat);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
/* Developer Notes: This should be implemented with a MatCreate_SchurComplement() as that is the standard design for new Mat classes. */
PetscErrorCode MatGetSchurComplement_Basic(Mat mat,IS isrow0,IS iscol0,IS isrow1,IS iscol1,MatReuse mreuse,Mat *newmat,MatSchurComplementAinvType ainvtype, MatReuse preuse,Mat *newpmat)
{
PetscErrorCode ierr;
Mat A=0,Ap=0,B=0,C=0,D=0;
PetscFunctionBegin;
PetscValidHeaderSpecific(mat,MAT_CLASSID,1);
PetscValidType(mat,1);
PetscValidHeaderSpecific(isrow0,IS_CLASSID,2);
PetscValidHeaderSpecific(iscol0,IS_CLASSID,3);
PetscValidHeaderSpecific(isrow1,IS_CLASSID,4);
PetscValidHeaderSpecific(iscol1,IS_CLASSID,5);
if (mreuse == MAT_IGNORE_MATRIX && preuse == MAT_IGNORE_MATRIX) PetscFunctionReturn(0);
if (mreuse == MAT_REUSE_MATRIX) PetscValidHeaderSpecific(*newmat,MAT_CLASSID,7);
if (preuse == MAT_REUSE_MATRIX) PetscValidHeaderSpecific(*newpmat,MAT_CLASSID,9);
if (mat->factortype) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
if (mreuse != MAT_IGNORE_MATRIX) {
/* Use MatSchurComplement */
if (mreuse == MAT_REUSE_MATRIX) {
ierr = MatSchurComplementGetSubMatrices(*newmat,&A,&Ap,&B,&C,&D);CHKERRQ(ierr);
if (!A || !Ap || !B || !C) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Attempting to reuse matrix but Schur complement matrices unset");
if (A != Ap) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Preconditioning matrix does not match operator");
ierr = MatDestroy(&Ap);CHKERRQ(ierr); /* get rid of extra reference */
}
}
ierr = MatGetSubMatrix(mat,isrow0,iscol0,mreuse,&A);CHKERRQ(ierr);
ierr = MatGetSubMatrix(mat,isrow0,iscol1,mreuse,&B);CHKERRQ(ierr);
ierr = MatGetSubMatrix(mat,isrow1,iscol0,mreuse,&C);CHKERRQ(ierr);
ierr = MatGetSubMatrix(mat,isrow1,iscol1,mreuse,&D);CHKERRQ(ierr);
switch (mreuse) {
case MAT_INITIAL_MATRIX:
ierr = MatCreateSchurComplement(A,A,B,C,D,newmat);CHKERRQ(ierr);
break;
case MAT_REUSE_MATRIX:
ierr = MatSchurComplementUpdateSubMatrices(*newmat,A,A,B,C,D);CHKERRQ(ierr);
break;
default:
if (mreuse != MAT_IGNORE_MATRIX) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"Unrecognized value of mreuse");
}
if (preuse != MAT_IGNORE_MATRIX) {
ierr = MatCreateSchurComplementPmat(A,B,C,D,ainvtype,preuse,newpmat);CHKERRQ(ierr);
}
ierr = MatDestroy(&A);CHKERRQ(ierr);
ierr = MatDestroy(&B);CHKERRQ(ierr);
ierr = MatDestroy(&C);CHKERRQ(ierr);
ierr = MatDestroy(&D);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
static PetscErrorCode PCApply_LSC(PC pc,Vec x,Vec y)
{
PC_LSC *lsc = (PC_LSC*)pc->data;
Mat A,B,C;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = MatSchurComplementGetSubMatrices(pc->mat,&A,NULL,&B,&C,NULL);CHKERRQ(ierr);
ierr = KSPSolve(lsc->kspL,x,lsc->x1);CHKERRQ(ierr);
ierr = MatMult(B,lsc->x1,lsc->x0);CHKERRQ(ierr);
if (lsc->scale) {
ierr = VecPointwiseMult(lsc->x0,lsc->x0,lsc->scale);CHKERRQ(ierr);
}
ierr = MatMult(A,lsc->x0,lsc->y0);CHKERRQ(ierr);
if (lsc->scale) {
ierr = VecPointwiseMult(lsc->y0,lsc->y0,lsc->scale);CHKERRQ(ierr);
}
ierr = MatMult(C,lsc->y0,lsc->x1);CHKERRQ(ierr);
ierr = KSPSolve(lsc->kspL,lsc->x1,y);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
static PetscErrorCode PCLSCAllocate_Private(PC pc)
{
PC_LSC *lsc = (PC_LSC*)pc->data;
Mat A;
PetscErrorCode ierr;
PetscFunctionBegin;
if (lsc->allocated) PetscFunctionReturn(0);
ierr = KSPCreate(PetscObjectComm((PetscObject)pc),&lsc->kspL);CHKERRQ(ierr);
ierr = KSPSetErrorIfNotConverged(lsc->kspL,pc->erroriffailure);CHKERRQ(ierr);
ierr = PetscObjectIncrementTabLevel((PetscObject)lsc->kspL,(PetscObject)pc,1);CHKERRQ(ierr);
ierr = KSPSetType(lsc->kspL,KSPPREONLY);CHKERRQ(ierr);
ierr = KSPSetOptionsPrefix(lsc->kspL,((PetscObject)pc)->prefix);CHKERRQ(ierr);
ierr = KSPAppendOptionsPrefix(lsc->kspL,"lsc_");CHKERRQ(ierr);
ierr = MatSchurComplementGetSubMatrices(pc->mat,&A,NULL,NULL,NULL,NULL);CHKERRQ(ierr);
ierr = MatCreateVecs(A,&lsc->x0,&lsc->y0);CHKERRQ(ierr);
ierr = MatCreateVecs(pc->pmat,&lsc->x1,NULL);CHKERRQ(ierr);
if (lsc->scalediag) {
ierr = VecDuplicate(lsc->x0,&lsc->scale);CHKERRQ(ierr);
}
lsc->allocated = PETSC_TRUE;
PetscFunctionReturn(0);
}
static PetscErrorCode PCSetUp_PCD_Feelpp(PC pc)
{
PetscErrorCode ierr;
PC_PCD_Feelpp *pcpcd = (PC_PCD_Feelpp*)pc->data;
if ( !pcpcd->allocated )
{
ierr = KSPCreate(PetscObjectComm((PetscObject)pc),&pcpcd->kspAp);CHKERRQ(ierr);
ierr = PetscObjectIncrementTabLevel((PetscObject)pcpcd->kspAp,(PetscObject)pc,1);CHKERRQ(ierr);
ierr = KSPSetType(pcpcd->kspAp,KSPPREONLY);CHKERRQ(ierr);
ierr = KSPSetOptionsPrefix(pcpcd->kspAp,((PetscObject)pc)->prefix);CHKERRQ(ierr);
ierr = KSPAppendOptionsPrefix(pcpcd->kspAp,"pcd_Ap");CHKERRQ(ierr);
ierr = KSPSetFromOptions(pcpcd->kspAp);CHKERRQ(ierr);
ierr = KSPCreate(PetscObjectComm((PetscObject)pc),&pcpcd->kspMp);CHKERRQ(ierr);
ierr = PetscObjectIncrementTabLevel((PetscObject)pcpcd->kspMp,(PetscObject)pc,1);CHKERRQ(ierr);
ierr = KSPSetType(pcpcd->kspMp,KSPPREONLY);CHKERRQ(ierr);
ierr = KSPSetOptionsPrefix(pcpcd->kspMp,((PetscObject)pc)->prefix);CHKERRQ(ierr);
ierr = KSPAppendOptionsPrefix(pcpcd->kspMp,"pcd_Mp");CHKERRQ(ierr);
ierr = KSPSetFromOptions(pcpcd->kspMp);CHKERRQ(ierr);
#if PETSC_VERSION_LESS_THAN(3,6,0)
ierr = MatGetVecs(pcpcd->matFp,&pcpcd->x2,&pcpcd->x1);CHKERRQ(ierr);
#else
ierr = MatCreateVecs(pcpcd->matFp,&pcpcd->x2,&pcpcd->x1);CHKERRQ(ierr);
#endif
pcpcd->allocated = PETSC_TRUE;
}
PetscBool isBTBt;
PetscStrcmp(pcpcd->pcdApType,"BTBt",&isBTBt);
if ( isBTBt )
{
if (!pcpcd->MvDiag )
{
#if PETSC_VERSION_LESS_THAN(3,6,0)
ierr = MatGetVecs(pcpcd->matMv,&pcpcd->MvDiag,NULL);CHKERRQ(ierr);
#else
ierr = MatCreateVecs(pcpcd->matMv,&pcpcd->MvDiag,NULL);CHKERRQ(ierr);
#endif
}
Mat B, C;
#if PETSC_VERSION_GREATER_OR_EQUAL_THAN( 3,5,0 )
ierr = MatSchurComplementGetSubMatrices(pc->mat,NULL,NULL,&B,&C,NULL);CHKERRQ(ierr);
#else
ierr = MatSchurComplementGetSubmatrices(pc->mat,NULL,NULL,&B,&C,NULL);CHKERRQ(ierr);
#endif
ierr = MatGetDiagonal(pcpcd->matMv,pcpcd->MvDiag);CHKERRQ(ierr);
ierr = VecReciprocal(pcpcd->MvDiag);CHKERRQ(ierr);
// diag(F)^-1 * B
ierr = MatDiagonalScale( B, pcpcd->MvDiag ,NULL);CHKERRQ(ierr);
// C* diag(F)^-1 * B
if ( !pcpcd->matApBTBt )
ierr = MatMatMult(C,B,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&pcpcd->matApBTBt);
else
ierr = MatMatMult(C,B,MAT_REUSE_MATRIX,PETSC_DEFAULT,&pcpcd->matApBTBt);
CHKERRQ(ierr);
ierr = VecReciprocal(pcpcd->MvDiag);CHKERRQ(ierr);
ierr = MatDiagonalScale( B, pcpcd->MvDiag ,NULL);CHKERRQ(ierr);
pcpcd->matAp = pcpcd->matApBTBt;
}
else
pcpcd->matAp = pcpcd->matApLaplacian;
#if PETSC_VERSION_GREATER_OR_EQUAL_THAN( 3,5,0 )
ierr = KSPSetOperators(pcpcd->kspAp,pcpcd->matAp,pcpcd->matAp);CHKERRQ(ierr);
ierr = KSPSetOperators(pcpcd->kspMp,pcpcd->matMp,pcpcd->matMp);CHKERRQ(ierr);
#else
ierr = KSPSetOperators(pcpcd->kspAp,pcpcd->matAp,pcpcd->matAp,SAME_PRECONDITIONER);CHKERRQ(ierr);
ierr = KSPSetOperators(pcpcd->kspMp,pcpcd->matMp,pcpcd->matMp,SAME_PRECONDITIONER);CHKERRQ(ierr);
#endif
PetscFunctionReturn(0);
}
PetscErrorCode PCBDDCSubSchursSetUp(PCBDDCSubSchurs sub_schurs, Mat S, IS is_A_I, IS is_A_B, PetscInt ncc, IS is_cc[], PetscInt xadj[], PetscInt adjncy[], PetscInt nlayers)
{
Mat A_II,A_IB,A_BI,A_BB;
ISLocalToGlobalMapping BtoNmap,ItoNmap;
PetscBT touched;
PetscInt i,n_I,n_B,n_local,*local_numbering;
PetscBool is_sorted;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = ISSorted(is_A_I,&is_sorted);CHKERRQ(ierr);
if (!is_sorted) {
SETERRQ(PetscObjectComm((PetscObject)is_A_I),PETSC_ERR_PLIB,"IS for I dofs should be shorted");
}
ierr = ISSorted(is_A_B,&is_sorted);CHKERRQ(ierr);
if (!is_sorted) {
SETERRQ(PetscObjectComm((PetscObject)is_A_B),PETSC_ERR_PLIB,"IS for B dofs should be shorted");
}
/* get sizes */
ierr = ISGetLocalSize(is_A_I,&n_I);CHKERRQ(ierr);
ierr = ISGetLocalSize(is_A_B,&n_B);CHKERRQ(ierr);
n_local = n_I+n_B;
/* maps */
ierr = ISLocalToGlobalMappingCreateIS(is_A_B,&BtoNmap);CHKERRQ(ierr);
if (nlayers >= 0 && xadj != NULL && adjncy != NULL) { /* I problems have a different size of the original ones */
ierr = ISLocalToGlobalMappingCreateIS(is_A_I,&ItoNmap);CHKERRQ(ierr);
/* allocate some auxiliary space */
ierr = PetscMalloc1(n_local,&local_numbering);CHKERRQ(ierr);
ierr = PetscBTCreate(n_local,&touched);CHKERRQ(ierr);
} else {
ItoNmap = 0;
local_numbering = 0;
touched = 0;
}
/* get Schur complement matrices */
ierr = MatSchurComplementGetSubMatrices(S,&A_II,NULL,&A_IB,&A_BI,&A_BB);CHKERRQ(ierr);
/* allocate space for schur complements */
ierr = PetscMalloc5(ncc,&sub_schurs->is_AEj_I,ncc,&sub_schurs->is_AEj_B,ncc,&sub_schurs->S_Ej,ncc,&sub_schurs->work1,ncc,&sub_schurs->work2);CHKERRQ(ierr);
sub_schurs->n_subs = ncc;
/* cycle on subsets and extract schur complements */
for (i=0;i<sub_schurs->n_subs;i++) {
Mat AE_II,AE_IE,AE_EI,AE_EE;
IS is_I,is_subset_B;
/* get IS for subsets in B numbering */
ierr = ISDuplicate(is_cc[i],&sub_schurs->is_AEj_B[i]);CHKERRQ(ierr);
ierr = ISSort(sub_schurs->is_AEj_B[i]);CHKERRQ(ierr);
ierr = ISGlobalToLocalMappingApplyIS(BtoNmap,IS_GTOLM_DROP,sub_schurs->is_AEj_B[i],&is_subset_B);CHKERRQ(ierr);
/* BB block on subset */
ierr = MatGetSubMatrix(A_BB,is_subset_B,is_subset_B,MAT_INITIAL_MATRIX,&AE_EE);CHKERRQ(ierr);
if (ItoNmap) { /* is ItoNmap has been computed, extracts only a part of I dofs */
const PetscInt* idx_B;
PetscInt n_local_dofs,n_prev_added,j,layer,subset_size;
/* all boundary dofs must be skipped when adding layers */
ierr = PetscBTMemzero(n_local,touched);CHKERRQ(ierr);
ierr = ISGetIndices(is_A_B,&idx_B);CHKERRQ(ierr);
for (j=0;j<n_B;j++) {
ierr = PetscBTSet(touched,idx_B[j]);CHKERRQ(ierr);
}
ierr = ISRestoreIndices(is_A_B,&idx_B);CHKERRQ(ierr);
/* add next layers of dofs */
ierr = ISGetLocalSize(is_cc[i],&subset_size);CHKERRQ(ierr);
ierr = ISGetIndices(is_cc[i],&idx_B);CHKERRQ(ierr);
ierr = PetscMemcpy(local_numbering,idx_B,subset_size*sizeof(PetscInt));CHKERRQ(ierr);
ierr = ISRestoreIndices(is_cc[i],&idx_B);CHKERRQ(ierr);
n_local_dofs = subset_size;
n_prev_added = subset_size;
for (layer=0;layer<nlayers;layer++) {
PetscInt n_added;
if (n_local_dofs == n_I+subset_size) break;
if (n_local_dofs > n_I+subset_size) {
SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Error querying layer %d. Out of bound access (%d > %d)",layer,n_local_dofs,n_I+subset_size);
}
ierr = PCBDDCAdjGetNextLayer_Private(local_numbering+n_local_dofs,n_prev_added,touched,xadj,adjncy,&n_added);CHKERRQ(ierr);
n_prev_added = n_added;
n_local_dofs += n_added;
if (!n_added) break;
}
/* IS for I dofs in original numbering and in I numbering */
ierr = ISCreateGeneral(PetscObjectComm((PetscObject)ItoNmap),n_local_dofs-subset_size,local_numbering+subset_size,PETSC_COPY_VALUES,&sub_schurs->is_AEj_I[i]);CHKERRQ(ierr);
ierr = ISSort(sub_schurs->is_AEj_I[i]);CHKERRQ(ierr);
ierr = ISGlobalToLocalMappingApplyIS(ItoNmap,IS_GTOLM_DROP,sub_schurs->is_AEj_I[i],&is_I);CHKERRQ(ierr);
/* II block */
ierr = MatGetSubMatrix(A_II,is_I,is_I,MAT_INITIAL_MATRIX,&AE_II);CHKERRQ(ierr);
} else { /* in this case we can take references of already existing IS and matrices for I dofs */
/* IS for I dofs in original numbering */
ierr = PetscObjectReference((PetscObject)is_A_I);CHKERRQ(ierr);
sub_schurs->is_AEj_I[i] = is_A_I;
/* IS for I dofs in I numbering TODO: "first" argument of ISCreateStride is not general */
ierr = ISCreateStride(PetscObjectComm((PetscObject)is_A_I),n_I,0,1,&is_I);CHKERRQ(ierr);
/* II block is the same */
ierr = PetscObjectReference((PetscObject)A_II);CHKERRQ(ierr);
AE_II = A_II;
}
/* IE block */
ierr = MatGetSubMatrix(A_IB,is_I,is_subset_B,MAT_INITIAL_MATRIX,&AE_IE);CHKERRQ(ierr);
/* EI block */
ierr = MatGetSubMatrix(A_BI,is_subset_B,is_I,MAT_INITIAL_MATRIX,&AE_EI);CHKERRQ(ierr);
/* setup Schur complements on subset */
ierr = MatCreateSchurComplement(AE_II,AE_II,AE_IE,AE_EI,AE_EE,&sub_schurs->S_Ej[i]);CHKERRQ(ierr);
ierr = MatGetVecs(sub_schurs->S_Ej[i],&sub_schurs->work1[i],&sub_schurs->work2[i]);CHKERRQ(ierr);
if (AE_II == A_II) { /* we can reuse the same ksp */
KSP ksp;
ierr = MatSchurComplementGetKSP(S,&ksp);CHKERRQ(ierr);
ierr = MatSchurComplementSetKSP(sub_schurs->S_Ej[i],ksp);CHKERRQ(ierr);
} else { /* build new ksp object which inherits ksp and pc types from the original one */
KSP origksp,schurksp;
PC origpc,schurpc;
KSPType ksp_type;
PCType pc_type;
PetscInt n_internal;
ierr = MatSchurComplementGetKSP(S,&origksp);CHKERRQ(ierr);
ierr = MatSchurComplementGetKSP(sub_schurs->S_Ej[i],&schurksp);CHKERRQ(ierr);
ierr = KSPGetType(origksp,&ksp_type);CHKERRQ(ierr);
ierr = KSPSetType(schurksp,ksp_type);CHKERRQ(ierr);
ierr = KSPGetPC(schurksp,&schurpc);CHKERRQ(ierr);
ierr = KSPGetPC(origksp,&origpc);CHKERRQ(ierr);
ierr = PCGetType(origpc,&pc_type);CHKERRQ(ierr);
ierr = PCSetType(schurpc,pc_type);CHKERRQ(ierr);
ierr = ISGetSize(is_I,&n_internal);CHKERRQ(ierr);
if (n_internal) { /* UMFPACK gives error with 0 sized problems */
MatSolverPackage solver=NULL;
ierr = PCFactorGetMatSolverPackage(origpc,(const MatSolverPackage*)&solver);CHKERRQ(ierr);
if (solver) {
ierr = PCFactorSetMatSolverPackage(schurpc,solver);CHKERRQ(ierr);
}
}
ierr = KSPSetUp(schurksp);CHKERRQ(ierr);
}
/* free */
ierr = MatDestroy(&AE_II);CHKERRQ(ierr);
ierr = MatDestroy(&AE_EE);CHKERRQ(ierr);
ierr = MatDestroy(&AE_IE);CHKERRQ(ierr);
ierr = MatDestroy(&AE_EI);CHKERRQ(ierr);
ierr = ISDestroy(&is_I);CHKERRQ(ierr);
ierr = ISDestroy(&is_subset_B);CHKERRQ(ierr);
}
/* free */
ierr = ISLocalToGlobalMappingDestroy(&ItoNmap);CHKERRQ(ierr);
ierr = ISLocalToGlobalMappingDestroy(&BtoNmap);CHKERRQ(ierr);
ierr = PetscFree(local_numbering);CHKERRQ(ierr);
ierr = PetscBTDestroy(&touched);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
