PetscErrorCode DMSetUp_AKKT(DM dm) {
DM_AKKT *kkt = (DM_AKKT*)(dm->data);
PetscErrorCode ierr;
PetscFunctionBegin;
if(dm->setupcalled) PetscFunctionReturn(0);
if(!kkt->Aff){
if(kkt->dm) {
ierr = DMCreateMatrix(kkt->dm, MATAIJ, &kkt->Aff); CHKERRQ(ierr);
}
else SETERRQ(((PetscObject)dm)->comm, PETSC_ERR_ARG_WRONGSTATE, "Neither matrix nor DM set");
}
if(!kkt->isf[0] && !kkt->isf[0]) {
if(kkt->detect_saddle_point) {
ierr = MatFindZeroDiagonals(kkt->Aff,&kkt->isf[1]);CHKERRQ(ierr);
}
else if(kkt->dm && kkt->dname) {
DM ddm;
PetscInt n;
char **names;
IS *iss;
DM *dms;
PetscInt i;
ierr = DMCreateFieldDecompositionDM(kkt->dm, kkt->dname, &ddm); CHKERRQ(ierr);
ierr = DMCreateFieldDecomposition(ddm, &n, &names, &iss, &dms); CHKERRQ(ierr);
if(n < 1 || n > 2)
SETERRQ2(((PetscObject)dm)->comm, PETSC_ERR_ARG_WRONG, "Number of parts in decomposition %s must be between 1 and 2. Got %D instead",kkt->dname, n);
for(i = 0; i < n; ++i) {
if(!iss[i] && dms[i]) {
const char* label;
if(i == 0)
label = "primal";
else
label = "dual";
SETERRQ1(((PetscObject)dm)->comm, PETSC_ERR_ARG_WRONG, "Decomposition defines %s subDM, but no embedding IS is given", label);
}
}
ierr = DMAKKTSetFieldDecomposition(dm, n, (const char**)names, iss, dms); CHKERRQ(ierr);
for(i = 0; i < n; ++i) {
ierr = PetscFree(names[i]); CHKERRQ(ierr);
ierr = ISDestroy(&(iss[i])); CHKERRQ(ierr);
ierr = DMDestroy(&(dms[i])); CHKERRQ(ierr);
}
}
}
if(!kkt->isf[0] && !kkt->isf[1]) SETERRQ(((PetscObject)dm)->comm, PETSC_ERR_ARG_WRONGSTATE, "Decomposition ISs not set and could not be derived. ");
if(!kkt->isf[0] || !kkt->isf[1]) {
PetscInt lstart, lend;
ierr = MatGetOwnershipRange(kkt->Aff, &lstart, &lend); CHKERRQ(ierr);
if(!kkt->isf[0]) {
ierr = ISComplement(kkt->isf[0], lstart, lend, kkt->isf+1); CHKERRQ(ierr);
}
else {
ierr = ISComplement(kkt->isf[1], lstart, lend, kkt->isf+0); CHKERRQ(ierr);
}
}
/* FIX: Should we allow a combination of empty kkt->dmf[0] and non-empty kkt->dmf[1]? */
if(!kkt->dmf[0]) {
/* Construct a GAMG proxy to coarsen the primal block. */
Mat A0f0f;
IS is00;
PetscInt lstart, lend;
const char* primal = {"all"};
ierr = DMCreate(((PetscObject)dm)->comm, kkt->dmf+0); CHKERRQ(ierr);
ierr = DMSetType(kkt->dmf[0],DMAKKT); CHKERRQ(ierr);
ierr = MatGetSubMatrix(kkt->Aff, kkt->isf[0], kkt->isf[0], MAT_INITIAL_MATRIX, &A0f0f); CHKERRQ(ierr);
ierr = DMAKKTSetMatrix(kkt->dmf[0], A0f0f); CHKERRQ(ierr);
ierr = MatGetOwnershipRange(A0f0f, &lstart, &lend); CHKERRQ(ierr);
ierr = ISCreateStride(((PetscObject)A0f0f)->comm, lend-lstart, lstart, 1, &is00); CHKERRQ(ierr);
ierr = DMAKKTSetFieldDecomposition(kkt->dmf[0], 1, &primal, &is00, PETSC_NULL); CHKERRQ(ierr);
}
dm->setupcalled = PETSC_TRUE;
PetscFunctionReturn(0);
}
static PetscErrorCode SNESMultiblockSetDefaults(SNES snes)
{
SNES_Multiblock *mb = (SNES_Multiblock *) snes->data;
BlockDesc blocks = mb->blocks;
PetscInt i;
PetscErrorCode ierr;
PetscFunctionBegin;
if (!blocks) {
if (snes->dm) {
PetscBool dmcomposite;
ierr = PetscObjectTypeCompare((PetscObject) snes->dm, DMCOMPOSITE, &dmcomposite);CHKERRQ(ierr);
if (dmcomposite) {
PetscInt nDM;
IS *fields;
ierr = PetscInfo(snes,"Setting up physics based multiblock solver using the embedded DM\n");CHKERRQ(ierr);
ierr = DMCompositeGetNumberDM(snes->dm, &nDM);CHKERRQ(ierr);
ierr = DMCompositeGetGlobalISs(snes->dm, &fields);CHKERRQ(ierr);
for (i = 0; i < nDM; ++i) {
char name[8];
ierr = PetscSNPrintf(name, sizeof(name), "%D", i);CHKERRQ(ierr);
ierr = SNESMultiblockSetIS(snes, name, fields[i]);CHKERRQ(ierr);
ierr = ISDestroy(&fields[i]);CHKERRQ(ierr);
}
ierr = PetscFree(fields);CHKERRQ(ierr);
}
} else {
PetscBool flg = PETSC_FALSE;
PetscBool stokes = PETSC_FALSE;
if (mb->bs <= 0) {
if (snes->jacobian_pre) {
ierr = MatGetBlockSize(snes->jacobian_pre, &mb->bs);CHKERRQ(ierr);
} else {
mb->bs = 1;
}
}
ierr = PetscOptionsGetBool(((PetscObject) snes)->prefix, "-snes_multiblock_default", &flg, PETSC_NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetBool(((PetscObject) snes)->prefix, "-snes_multiblock_detect_saddle_point", &stokes, PETSC_NULL);CHKERRQ(ierr);
if (stokes) {
IS zerodiags, rest;
PetscInt nmin, nmax;
ierr = MatGetOwnershipRange(snes->jacobian_pre, &nmin, &nmax);CHKERRQ(ierr);
ierr = MatFindZeroDiagonals(snes->jacobian_pre, &zerodiags);CHKERRQ(ierr);
ierr = ISComplement(zerodiags, nmin, nmax, &rest);CHKERRQ(ierr);
ierr = SNESMultiblockSetIS(snes, "0", rest);CHKERRQ(ierr);
ierr = SNESMultiblockSetIS(snes, "1", zerodiags);CHKERRQ(ierr);
ierr = ISDestroy(&zerodiags);CHKERRQ(ierr);
ierr = ISDestroy(&rest);CHKERRQ(ierr);
} else {
if (!flg) {
/* Allow user to set fields from command line, if bs was known at the time of SNESSetFromOptions_Multiblock()
then it is set there. This is not ideal because we should only have options set in XXSetFromOptions(). */
ierr = SNESMultiblockSetFieldsRuntime_Private(snes);CHKERRQ(ierr);
if (mb->defined) {ierr = PetscInfo(snes, "Blocks defined using the options database\n");CHKERRQ(ierr);}
}
if (flg || !mb->defined) {
ierr = PetscInfo(snes, "Using default splitting of fields\n");CHKERRQ(ierr);
for (i = 0; i < mb->bs; ++i) {
char name[8];
ierr = PetscSNPrintf(name, sizeof(name), "%D", i);CHKERRQ(ierr);
ierr = SNESMultiblockSetFields(snes, name, 1, &i);CHKERRQ(ierr);
}
mb->defaultblocks = PETSC_TRUE;
}
}
}
} else if (mb->numBlocks == 1) {
if (blocks->is) {
IS is2;
PetscInt nmin, nmax;
ierr = MatGetOwnershipRange(snes->jacobian_pre, &nmin, &nmax);CHKERRQ(ierr);
ierr = ISComplement(blocks->is, nmin, nmax, &is2);CHKERRQ(ierr);
ierr = SNESMultiblockSetIS(snes, "1", is2);CHKERRQ(ierr);
ierr = ISDestroy(&is2);CHKERRQ(ierr);
} else {
SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Must provide at least two sets of fields to SNES multiblock");
}
}
if (mb->numBlocks < 2) SETERRQ(PETSC_COMM_SELF, PETSC_ERR_PLIB, "Unhandled case, must have at least two blocks");
PetscFunctionReturn(0);
}
