xref: /petsc/include/petscdmtypes.h (revision 0b4b7b1c20c2ed4ade67e3d50a7710fe0ffbfca5)

#pragma once

/* SUBMANSEC = DM */

/*S
   DM - Abstract PETSc object that manages an abstract grid-like object and its interactions with the algebraic solvers

   Level: intermediate

   Note:
   `DM` is an orphan initialism or orphan acronym, the letters have no meaning and never did.

.seealso: [](ch_dmbase), `DMType`, `DMGetType()`, `DMCompositeCreate()`, `DMDACreate()`, `DMSetType()`, `DMType`, `DMDA`, `DMPLEX`
S*/
typedef struct _p_DM *DM;

/*E
  DMBoundaryType - Describes the choice for the filling of ghost cells on physical domain boundaries.

  Values:
+ `DM_BOUNDARY_NONE`     - no ghost nodes
. `DM_BOUNDARY_GHOSTED`  - ghost vertices/cells exist but aren't filled; you can put values into them and then apply a stencil that uses those ghost locations
. `DM_BOUNDARY_MIRROR`   - the ghost value is the same as the value 1 grid point in; that is, the 0th grid point in the real mesh acts like a mirror to define
                           the ghost point value; not yet implemented for 3d
. `DM_BOUNDARY_PERIODIC` - ghost vertices/cells filled by the opposite edge of the domain
- `DM_BOUNDARY_TWIST`    - like periodic, only glued backwards like a Mobius strip

  Level: beginner

  Notes:
  This is information for the boundary of the __PHYSICAL__ domain. It has nothing to do with boundaries between
  processes. That width is always determined by the stencil width; see `DMDASetStencilWidth()`.

  If the physical grid points have values 0 1 2 3 with `DM_BOUNDARY_MIRROR` then the local vector with ghost points has the values 1 0 1 2 3 2.

  See <https://scicomp.stackexchange.com/questions/5355/writing-the-poisson-equation-finite-difference-matrix-with-neumann-boundary-cond>

  Developer Note:
  Should `DM_BOUNDARY_MIRROR` have the same meaning with `DMDA_Q0`, that is a staggered grid? In that case should the ghost point have the same value
  as the 0th grid point where the physical boundary serves as the mirror?

.seealso: [](ch_dmbase), `DM`, `DMDA`, `DMDASetBoundaryType()`, `DMDACreate1d()`, `DMDACreate2d()`, `DMDACreate3d()`, `DMDACreate()`
E*/
typedef enum {
  DM_BOUNDARY_NONE,
  DM_BOUNDARY_GHOSTED,
  DM_BOUNDARY_MIRROR,
  DM_BOUNDARY_PERIODIC,
  DM_BOUNDARY_TWIST
} DMBoundaryType;

/*E
  DMBoundaryConditionType - indicates what type of boundary condition is to be imposed

  Values:
+ `DM_BC_ESSENTIAL`          - A Dirichlet condition using a function of the coordinates
. `DM_BC_ESSENTIAL_FIELD`    - A Dirichlet condition using a function of the coordinates and auxiliary field data
. `DM_BC_ESSENTIAL_BD_FIELD` - A Dirichlet condition using a function of the coordinates, facet normal, and auxiliary field data
. `DM_BC_NATURAL`            - A Neumann condition using a function of the coordinates
. `DM_BC_NATURAL_FIELD`      - A Neumann condition using a function of the coordinates and auxiliary field data
- `DM_BC_NATURAL_RIEMANN`    - A flux condition which determines the state in ghost cells

  Level: beginner

  Note:
  The user can check whether a boundary condition is essential using (type & `DM_BC_ESSENTIAL`), and similarly for
  natural conditions (type & `DM_BC_NATURAL`)

.seealso: [](ch_dmbase), `DM`, `DMAddBoundary()`, `DSAddBoundary()`, `DSGetBoundary()`
E*/
typedef enum {
  DM_BC_ESSENTIAL          = 1,
  DM_BC_ESSENTIAL_FIELD    = 5,
  DM_BC_NATURAL            = 2,
  DM_BC_NATURAL_FIELD      = 6,
  DM_BC_ESSENTIAL_BD_FIELD = 9,
  DM_BC_NATURAL_RIEMANN    = 10
} DMBoundaryConditionType;

/*E
  DMPointLocationType - Describes the method to handle point location failure

  Values:
+  `DM_POINTLOCATION_NONE`    - return a negative cell number
.  `DM_POINTLOCATION_NEAREST` - the (approximate) nearest point in the mesh is used
-  `DM_POINTLOCATION_REMOVE`  - returns values only for points which were located

  Level: intermediate

.seealso: [](ch_dmbase), `DM`, `DMLocatePoints()`
E*/
typedef enum {
  DM_POINTLOCATION_NONE,
  DM_POINTLOCATION_NEAREST,
  DM_POINTLOCATION_REMOVE
} DMPointLocationType;

/*E
  DMBlockingType - Describes how to choose variable block sizes

  Values:
+  `DM_BLOCKING_TOPOLOGICAL_POINT` - select all fields at a topological point (cell center, at a face, etc)
-  `DM_BLOCKING_FIELD_NODE`        - using a separate block for each field at a topological point

  Level: intermediate

  Note:
  When using `PCVPBJACOBI`, one can choose to block by topological point (all fields at a cell center, at a face, etc.)
  or by field nodes (using number of components per field to identify "nodes"). Field nodes lead to smaller blocks, but
  may converge more slowly. For example, a cubic Lagrange hexahedron will have one node at vertices, two at edges, four
  at faces, and eight at cell centers. If using point blocking, the `PCVPBJACOBI` preconditioner will work with block
  sizes up to 8 Lagrange nodes. For 5-component CFD, this produces matrices up to 40x40, which increases memory
  footprint and may harm performance. With field node blocking, the maximum block size will correspond to one Lagrange node,
  or 5x5 blocks for the CFD example.

.seealso: [](ch_dmbase), `PCVPBJACOBI`, `MatSetVariableBlockSizes()`, `DMSetBlockingType()`
E*/
typedef enum {
  DM_BLOCKING_TOPOLOGICAL_POINT,
  DM_BLOCKING_FIELD_NODE
} DMBlockingType;

/*E
  DMAdaptationStrategy - Describes the strategy used for adaptive solves

  Values:
+  `DM_ADAPTATION_INITIAL`    - refine a mesh based on an initial guess
.  `DM_ADAPTATION_SEQUENTIAL` - refine the mesh based on a sequence of solves, much like grid sequencing
-  `DM_ADAPTATION_MULTILEVEL` - use the sequence of constructed meshes in a multilevel solve, much like the Systematic Upscaling of Brandt

  Level: beginner

.seealso: [](ch_dmbase), `DM`, `DMAdaptor`, `DMAdaptationCriterion`, `DMAdaptorSolve()`
E*/
typedef enum {
  DM_ADAPTATION_INITIAL,
  DM_ADAPTATION_SEQUENTIAL,
  DM_ADAPTATION_MULTILEVEL
} DMAdaptationStrategy;

/*E
  DMAdaptationCriterion - Describes the test used to decide whether to coarsen or refine parts of the mesh

  Values:
+ `DM_ADAPTATION_REFINE` - uniformly refine a mesh, much like grid sequencing
. `DM_ADAPTATION_LABEL`  - adapt the mesh based upon a label of the cells filled with `DMAdaptFlag` markers.
. `DM_ADAPTATION_METRIC` - try to mesh the manifold described by the input metric tensor uniformly. PETSc can also construct such a metric based
                           upon an input primal or a gradient field.
- `DM_ADAPTATION_NONE`   - do no adaptation

  Level: beginner

.seealso: [](ch_dmbase), `DM`, `DMAdaptor`, `DMAdaptationStrategy`, `DMAdaptorSolve()`
E*/
typedef enum {
  DM_ADAPTATION_NONE,
  DM_ADAPTATION_REFINE,
  DM_ADAPTATION_LABEL,
  DM_ADAPTATION_METRIC
} DMAdaptationCriterion;
PETSC_EXTERN const char *const DMAdaptationCriteria[];

/*E
  DMAdaptFlag - Marker in the label prescribing what adaptation to perform

  Values:
+  `DM_ADAPT_DETERMINE`    - undocumented
.  `DM_ADAPT_KEEP`         - undocumented
.  `DM_ADAPT_REFINE`       - undocumented
.  `DM_ADAPT_COARSEN`      - undocumented
-  `DM_ADAPT_COARSEN_LAST` - undocumented

  Level: beginner

.seealso: [](ch_dmbase), `DM`, `DMAdaptor`, `DMAdaptationStrategy`, `DMAdaptationCriterion`, `DMAdaptorSolve()`, `DMAdaptLabel()`
E*/
typedef enum {
  DM_ADAPT_DETERMINE = PETSC_DETERMINE,
  DM_ADAPT_KEEP      = 0,
  DM_ADAPT_REFINE,
  DM_ADAPT_COARSEN,
  DM_ADAPT_COARSEN_LAST,
  DM_ADAPT_RESERVED_COUNT
} DMAdaptFlag;

/*E
  DMDirection - Indicates a coordinate direction

   Values:
+  `DM_X` - the x coordinate direction
.  `DM_Y` - the y coordinate direction
-  `DM_Z` - the z coordinate direction

  Level: beginner

.seealso: [](ch_dmbase), `DM`, `DMDA`, `DMDAGetRay()`, `DMDAGetProcessorSubset()`, `DMPlexShearGeometry()`
E*/
typedef enum {
  DM_X,
  DM_Y,
  DM_Z
} DMDirection;

/*E
  DMEnclosureType - The type of enclosure relation between one `DM` and another

   Values:
+  `DM_ENC_SUBMESH`   - the `DM` is the boundary of another `DM`
.  `DM_ENC_SUPERMESH` - the `DM` has the boundary of another `DM` (the reverse situation to `DM_ENC_SUBMESH`)
.  `DM_ENC_EQUALITY`  - it is unknown what this means
.  `DM_ENC_NONE`      - no relationship can be determined
-  `DM_ENC_UNKNOWN`   - the relationship is unknown

  Level: beginner

.seealso: [](ch_dmbase), `DM`, `DMGetEnclosureRelation()`
E*/
typedef enum {
  DM_ENC_EQUALITY,
  DM_ENC_SUPERMESH,
  DM_ENC_SUBMESH,
  DM_ENC_NONE,
  DM_ENC_UNKNOWN
} DMEnclosureType;

/*E
  DMPolytopeType - This describes the polytope represented by each cell.

  Level: beginner

  While most operations only need the topology information in the `DMPLEX`, we must sometimes have the
  user specify a polytope. For instance, when interpolating from a cell-vertex mesh, the type of
  polytope can be ambiguous. Also, `DMPLEX` allows different symmetries of a prism cell with the same
  constituent points. Normally these types are automatically inferred and the user does not specify
  them.

.seealso: [](ch_dmbase), `DM`, `DMPlexComputeCellTypes()`
E*/
typedef enum {
  DM_POLYTOPE_POINT,
  DM_POLYTOPE_SEGMENT,
  DM_POLYTOPE_POINT_PRISM_TENSOR,
  DM_POLYTOPE_TRIANGLE,
  DM_POLYTOPE_QUADRILATERAL,
  DM_POLYTOPE_SEG_PRISM_TENSOR,
  DM_POLYTOPE_TETRAHEDRON,
  DM_POLYTOPE_HEXAHEDRON,
  DM_POLYTOPE_TRI_PRISM,
  DM_POLYTOPE_TRI_PRISM_TENSOR,
  DM_POLYTOPE_QUAD_PRISM_TENSOR,
  DM_POLYTOPE_PYRAMID,
  DM_POLYTOPE_FV_GHOST,
  DM_POLYTOPE_INTERIOR_GHOST,
  DM_POLYTOPE_UNKNOWN,
  DM_POLYTOPE_UNKNOWN_CELL,
  DM_POLYTOPE_UNKNOWN_FACE,
  DM_NUM_POLYTOPES
} DMPolytopeType;
PETSC_EXTERN const char *const DMPolytopeTypes[];

/*E
  PetscUnit - The seven fundamental SI units

  Level: beginner

.seealso: `DMPlexGetScale()`, `DMPlexSetScale()`
E*/
typedef enum {
  PETSC_UNIT_LENGTH,
  PETSC_UNIT_MASS,
  PETSC_UNIT_TIME,
  PETSC_UNIT_CURRENT,
  PETSC_UNIT_TEMPERATURE,
  PETSC_UNIT_AMOUNT,
  PETSC_UNIT_LUMINOSITY,
  NUM_PETSC_UNITS
} PetscUnit;

/*E
   DMReorderDefaultFlag - Flag indicating whether the `DM` should be reordered by default

   Values:
+  `DM_REORDER_DEFAULT_NOTSET` - Flag not set.
.  `DM_REORDER_DEFAULT_FALSE`  - Do not reorder by default.
-  `DM_REORDER_DEFAULT_TRUE`   - Reorder by default.

   Level: intermediate

   Developer Note:
   Could be replaced with `PETSC_BOOL3`

.seealso: `DMPlexReorderSetDefault()`, `DMPlexReorderGetDefault()`, `DMPlexGetOrdering()`, `DMPlexPermute()`
E*/
typedef enum {
  DM_REORDER_DEFAULT_NOTSET = -1,
  DM_REORDER_DEFAULT_FALSE  = 0,
  DM_REORDER_DEFAULT_TRUE
} DMReorderDefaultFlag;

/*S
    DMField - PETSc object for defining a field on a mesh topology

    Level: intermediate

.seealso: [](ch_dmbase), `DM`, `DMUniversalLabel`, `DMLabelCreate()`
S*/
typedef struct _p_DMField *DMField;

/*S
    DMUniversalLabel - A label that encodes a set of `DMLabel`s, bijectively

    Level: developer

.seealso: [](ch_dmbase), `DM`, `DMLabel`, `DMUniversalLabelCreate()`
S*/
typedef struct _p_UniversalLabel *DMUniversalLabel;

typedef struct _PETSc_DMCEED *DMCeed;

typedef struct _n_DMGeneratorFunctionList *DMGeneratorFunctionList;