DofMap.h

Note

The documentation on this page was automatically extracted from the DOLFIN C++ code and may need to be edited or expanded.

class DofMap

Parent class(es)

• GenericDofMap

This class handles the mapping of degrees of freedom. It builds a dof map based on a ufc::dofmap on a specific mesh. It will reorder the dofs when running in parallel. Sub-dofmaps, both views and copies, are supported.

DofMap(std::shared_ptr<const ufc::dofmap> ufc_dofmap, const Mesh& mesh)

Create dof map on mesh (mesh is not stored)

Arguments

ufc_dofmap (ufc::dofmap)

The ufc::dofmap.

mesh (Mesh)

The mesh.

DofMap(std::shared_ptr<const ufc::dofmap> ufc_dofmap, const Mesh& mesh, std::shared_ptr<const SubDomain> constrained_domain)

Create a periodic dof map on mesh (mesh is not stored)

Arguments

ufc_dofmap (ufc::dofmap)

The ufc::dofmap.

mesh (Mesh)

The mesh.

constrained_boundary (SubDomain)

The subdomain marking the constrained (tied) boundaries.

bool is_view() const

True iff dof map is a view into another map

Returns

bool

True if the dof map is a sub-dof map (a view into another map).

std::size_t global_dimension() const

Return the dimension of the global finite element function space

Returns

std::size_t

The dimension of the global finite element function space.

std::size_t local_dimension(std::string type) const

Return number of owned, unowned, or all dofs in the dofmap on this process

Arguments

type (std::string)

Either “owned”, “unowned”, or “all”

Returns

std::size_t

Number of local dofs.

std::size_t num_element_dofs(std::size_t cell_index) const

Return the dimension of the local finite element function space on a cell

Arguments

cell_index (std::size_t)

Index of cell

Returns

std::size_t

Dimension of the local finite element function space.

std::size_t max_element_dofs() const

Return the maximum dimension of the local finite element function space

Returns

std::size_t

Maximum dimension of the local finite element function space.

std::size_t num_entity_dofs(std::size_t dim) const

Return the number of dofs for a given entity dimension

Arguments

dim (std::size_t)

Entity dimension

Returns

std::size_t

Number of dofs associated with given entity dimension

std::size_t num_facet_dofs() const

Return number of facet dofs

Returns

std::size_t

The number of facet dofs.

std::pair<std::size_t, std::size_t> ownership_range() const

Return the ownership range (dofs in this range are owned by this process)

Returns

std::pair<std::size_t, std::size_t>

The ownership range.

const std::vector<int>& off_process_owner() const

Return map from nonlocal dofs that appear in local dof map to owning process

Returns

std::vector<unsigned int>

The map from non-local dofs.

const std::unordered_map<int, std::vector<int>>& shared_nodes() const

Return map from all shared nodes to the sharing processes (not including the current process) that share it.

Returns

std::unordered_map<std::size_t, std::vector<unsigned int> >

The map from dofs to list of processes

const std::set<int>& neighbours() const

Return set of processes that share dofs with this process

Returns

std::set<int>

The set of processes

void clear_sub_map_data()

Clear any data required to build sub-dofmaps (this is to reduce memory use)

ArrayView<const dolfin::la_index> cell_dofs(std::size_t cell_index) const

Local-to-global mapping of dofs on a cell

Arguments

cell_index (std::size_t)

The cell index.

Returns

ArrayView<const dolfin::la_index>

Local-to-global mapping of dofs.

void tabulate_facet_dofs(std::vector<std::size_t>& dofs, std::size_t local_facet) const

Tabulate local-local facet dofs

Arguments

dofs (std::size_t)

Degrees of freedom.

local_facet (std::size_t)

The local facet.

void tabulate_entity_dofs(std::vector<std::size_t>& dofs, std::size_t dim, std::size_t local_entity) const

Tabulate local-local mapping of dofs on entity (dim, local_entity)

Arguments

dofs (std::size_t)

Degrees of freedom.

dim (std::size_t)

The entity dimension

local_entity (std::size_t)

The local entity index

void tabulate_coordinates(boost::multi_array<double, 2>& coordinates, const std::vector<double>& vertex_coordinates, const Cell& cell) const

Tabulate the coordinates of all dofs on a cell (UFC cell version)

Arguments

coordinates (boost::multi_array<double, 2>)

The coordinates of all dofs on a cell.

vertex_coordinates (std::vector<double>)

The cell vertex coordinates

cell (Cell)

The cell.

std::vector<double> tabulate_all_coordinates(const Mesh& mesh) const

Tabulate the coordinates of all dofs on this process. This function is typically used by preconditioners that require the spatial coordinates of dofs, for example for re-partitioning or nullspace computations.

Arguments

mesh (Mesh)

The mesh.

Returns

std::vector<double>

The dof coordinates (x0, y0, x1, y1, . . .)

std::shared_ptr<GenericDofMap> copy() const

Create a copy of the dof map

Returns

DofMap

The Dofmap copy.

std::shared_ptr<GenericDofMap> create(const Mesh& new_mesh) const

Create a copy of the dof map on a new mesh

Arguments

new_mesh (Mesh)

The new mesh to create the dof map on.

Returns

DofMap

The new Dofmap copy.

std::shared_ptr<GenericDofMap> extract_sub_dofmap(const std::vector<std::size_t>& component, const Mesh& mesh) const

Extract subdofmap component

Arguments

component (std::vector<std::size_t>)

The component.

mesh (Mesh)

The mesh.

Returns

DofMap

The subdofmap component.

std::shared_ptr<GenericDofMap> collapse(std::unordered_map<std::size_t, std::size_t>& collapsed_map, const Mesh& mesh) const

Create a “collapsed” dofmap (collapses a sub-dofmap)

Arguments

collapsed_map (std::unordered_map<std::size_t, std::size_t>)

The “collapsed” map.

mesh (Mesh)

The mesh.

Returns

DofMap

The collapsed dofmap.

std::vector<dolfin::la_index> dofs(const Mesh& mesh, std::size_t dim) const

Return list of dof indices on this process that belong to mesh entities of dimension dim

void set(GenericVector& x, double value) const

Set dof entries in vector to a specified value. Parallel layout of vector must be consistent with dof map range. This function is typically used to construct the null space of a matrix operator.

Arguments

vector (GenericVector)

The vector to set.

value (double)

The value to set.

void set_x(GenericVector& x, double value, std::size_t component, const Mesh& mesh) const

Set dof entries in vector to the x[i] coordinate of the dof spatial coordinate. Parallel layout of vector must be consistent with dof map range This function is typically used to construct the null space of a matrix operator, e.g. rigid body rotations.

Arguments

vector (GenericVector)

The vector to set.

value (double)

The value to multiply to coordinate by.

component (std::size_t)

The coordinate index.

mesh (Mesh)

The mesh.

const std::vector<std::size_t>& local_to_global_unowned() const

Return the map from unowned local dofmap nodes to global dofmap nodes. Dofmap node is dof index modulo block size.

Returns

_std::vector<std::size_t>_

The unonwed local-to-global node map.

void tabulate_local_to_global_dofs(std::vector<std::size_t>& local_to_global_map) const

Compute the map from local (this process) dof indices to global dof indices.

Arguments

local_to_global_map (_std::vector<std::size_t>_)

The local-to-global map to fill.

std::size_t local_to_global_index(int local_index) const

Return global dof index for a given local (process) dof index

Arguments

local_index (int)

The local local index.

Returns

std::size_t

The global dof index.

std::string str(bool verbose) const

Return informal string representation (pretty-print)

Arguments

verbose (bool)

Flag to turn on additional output.

Returns

std::string

An informal representation of the function space.