Form

class dolfin.cpp.fem.Form(*args)

Bases: dolfin.cpp.fem.HierarchicalForm

Base class for UFC code generated by FFC for DOLFIN with option -l.

embed:rst:leading-slashes
/// A note on the order of trial and test spaces: FEniCS numbers
/// argument spaces starting with the leading dimension of the
/// corresponding tensor (matrix). In other words, the test space is
/// numbered 0 and the trial space is numbered 1. However, in order
/// to have a notation that agrees with most existing finite element
/// literature, in particular
///
///     a = a(u, v)
///
/// the spaces are numbered from right to
///
///     a: V_1 x V_0 -> R
///
/// .. note::
///
///     Figure out how to write this in math mode without it getting
///     messed up in the Python version.
///
/// This is reflected in the ordering of the spaces that should be
/// supplied to generated subclasses. In particular, when a bilinear
/// form is initialized, it should be initialized as
///
/// .. code-block:: c++
///
///     a(V_1, V_0) = ...
///
/// where ``V_1`` is the trial space and ``V_0`` is the test space.
/// However, when a form is initialized by a list of argument spaces
/// (the variable ``function_spaces`` in the constructors below, the
/// list of spaces should start with space number 0 (the test space)
/// and then space number 1 (the trial space).
///

Create form (shared data)

Parameters:
  • const ufc::form > ufc_form (std::shared_ptr<) – (ufc::form) The UFC form. [direction=in]
  • std::shared_ptr< const FunctionSpace >> function_spaces (std::vector<) – (std::vector<FunctionSpace >) Vector of function spaces. [direction=in]
cell_domains()

Return cell domains (zero pointer if no domains have been specified)

Return type:std::shared_ptr< const MeshFunction< std::size_t > >
Returns:MeshFunction <std::size_t> The cell domains.
check()

Check function spaces and coefficients.

Return type:void
coefficient()

Return coefficient with given number

Parameters:i (std::size_t) – (std::size_t) Index [direction=in]
Return type:std::shared_ptr< const GenericFunction >
Returns:GenericFunction The coefficient.
coefficient_name()

Return the name of the coefficient with this number

Parameters:i (std::size_t) – (std::size_t) The number [direction=in]
Return type:std::string
Returns:std::string The name of the coefficient with the given number.
coefficient_number()

Return the number of the coefficient with this name

Parameters:std::string & name (const) – (std::string) The name. [direction=in]
Return type:std::size_t
Returns:std::size_t The number of the coefficient with the given name.
coefficients()

Return all coefficients

Return type:std::vector< std::shared_ptr< const GenericFunction > >
Returns:std::vector<GenericFunction > All coefficients.
coloring()

Return coloring type for colored assembly of form over a mesh entity of a given dimension

Parameters:entity_dim (std::size_t) – (std::size_t) Dimension. [direction=in]
Return type:std::vector< std::size_t >
Returns:std::vector<std::size_t> Coloring type.
exterior_facet_domains()

Return exterior facet domains (zero pointer if no domains have been specified)

Return type:std::shared_ptr< const MeshFunction< std::size_t > >
Returns:std::shared_ptr<MeshFunction <std::size_t>> The exterior facet domains.
function_space(i)

Return function space for given argument

Arguments
i (std::size_t)
Index
Returns
_FunctionSpace_
Function space shared pointer.
function_spaces()

Return function spaces for arguments

Return type:std::vector< std::shared_ptr< const FunctionSpace > >
Returns:std::vector<FunctionSpace > Vector of function space shared pointers.
interior_facet_domains()

Return interior facet domains (zero pointer if no domains have been specified)

Return type:std::shared_ptr< const MeshFunction< std::size_t > >
Returns:MeshFunction <std::size_t> The interior facet domains.
mesh()

Extract common mesh from form

Return type:std::shared_ptr< const Mesh >
Returns:Mesh Shared pointer to the mesh.
num_coefficients()

Return number of coefficients

Return type:std::size_t
Returns:std::size_t The number of coefficients.
original_coefficient_position()

Return original coefficient position for each coefficient (0 <= i < n)

Parameters:i (std::size_t) –
Return type:std::size_t
Returns:std::size_t The position of coefficient i in original ufl form coefficients.
rank()

Return rank of form (bilinear form = 2, linear form = 1, functional = 0, etc)

Return type:std::size_t
Returns:std::size_t The rank of the form.
set_cell_domains()

Set cell domains

Parameters:const MeshFunction< std::size_t >> cell_domains (std::shared_ptr<) – (MeshFunction <std::size_t>) The cell domains. [direction=in]
Return type:void
set_coefficient()

Set coefficient with given number (shared pointer version)

Parameters:
  • i (std::size_t) – (std::size_t) The given number. [direction=in]
  • const GenericFunction > coefficient (std::shared_ptr<) – (GenericFunction ) The coefficient. [direction=in]
Return type:

void

set_coefficients()

Set all coefficients in given map. All coefficients in the given map, which may contain only a subset of the coefficients of the form, will be set.

Parameters:std::string, std::shared_ptr< const GenericFunction >> coefficients (std::map<) – (std::map<std::string, GenericFunction >) The map of coefficients. [direction=in]
Return type:void
set_exterior_facet_domains()

Set exterior facet domains

Parameters:const MeshFunction< std::size_t >> exterior_facet_domains (std::shared_ptr<) – (MeshFunction <std::size_t>) The exterior facet domains. [direction=in]
Return type:void
set_interior_facet_domains()

Set interior facet domains

Parameters:const MeshFunction< std::size_t >> interior_facet_domains (std::shared_ptr<) – (MeshFunction <std::size_t>) The interior facet domains. [direction=in]
Return type:void
set_mesh()

Set mesh, necessary for functionals when there are no function spaces

Parameters:const Mesh > mesh (std::shared_ptr<) – (Mesh ) The mesh. [direction=in]
Return type:void
set_some_coefficients()

Set some coefficients in given map. Each coefficient in the given map will be set, if the name of the coefficient matches the name of a coefficient in the form. This is useful when reusing the same coefficient map for several forms, or when some part of the form has been outcommented (for testing) in the UFL file, which means that the coefficient and attaching it to the form does not need to be outcommented in a C++ program using code from the generated UFL file.

Parameters:std::string, std::shared_ptr< const GenericFunction >> coefficients (std::map<) – (std::map<std::string, GenericFunction >) The map of coefficients. [direction=in]
Return type:void
set_vertex_domains()

Set vertex domains

Parameters:const MeshFunction< std::size_t >> vertex_domains (std::shared_ptr<) – (MeshFunction <std::size_t>) The vertex domains. [direction=in]
Return type:void
thisown

The membership flag

ufc_form()

Return UFC form shared pointer

Return type:std::shared_ptr< const ufc::form >
Returns:ufc::form The UFC form.
vertex_domains()

Return vertex domains (zero pointer if no domains have been specified)

Return type:std::shared_ptr< const MeshFunction< std::size_t > >
Returns:MeshFunction <std::size_t> The vertex domains.