PETSC_STATIC_INLINE PetscErrorCode DMPlexGetGlobalFieldOffset_Private(DM dm,PetscInt point,PetscInt field,PetscInt *offset)
{
PetscFunctionBegin;
#if defined(PETSC_USE_DEBUG)
{
PetscErrorCode ierr;
PetscInt loff,lfoff,dof,cdof;
ierr = PetscSectionGetOffset(dm->defaultGlobalSection,point,offset);CHKERRQ(ierr);
ierr = PetscSectionGetOffset(dm->defaultSection,point,&loff);CHKERRQ(ierr);
ierr = PetscSectionGetFieldOffset(dm->defaultSection,point,field,&lfoff);CHKERRQ(ierr);
ierr = PetscSectionGetFieldDof(dm->defaultSection,point,field,&dof);CHKERRQ(ierr);
ierr = PetscSectionGetFieldConstraintDof(dm->defaultSection,point,field,&cdof);CHKERRQ(ierr);
*offset += lfoff - loff;
if (dof-cdof <= 0) *offset = -1; /* Indicates no data */
}
#else
{
PetscSection s = dm->defaultSection;
PetscSection fs = dm->defaultSection->field[field];
PetscSection gs = dm->defaultGlobalSection;
PetscInt dof,cdof,loff,lfoff;
loff = s->atlasOff[point - s->pStart];
lfoff = fs->atlasOff[point - s->pStart];
dof = s->atlasDof[point - s->pStart];
cdof = s->bc ? s->bc->atlasDof[point - s->bc->pStart] : 0;
*offset = gs->atlasOff[point - s->pStart] + lfoff - loff;
if (dof-cdof <= 0) *offset = -1;
}
#endif
PetscFunctionReturn(0);
}
/* 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);
}
/* 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);
}