Function create_form

python/dolfinx/fem/forms.py:607–686

Create a Form object from a data-independent compiled form. Args: form: Compiled ufl form, V: List of function spaces associated with the form. Should match the number of arguments in the form. msh: Mesh to associate form with. subdomains: A map from

(
    form: CompiledForm,
    V: list[FunctionSpace],
    msh: Mesh,
    subdomains: dict[IntegralType, list[tuple[int, np.ndarray]]],
    coefficient_map: dict[ufl.Coefficient, Function],
    constant_map: dict[ufl.Constant, Constant],
    entity_maps: Sequence[_EntityMap] | None = None,
)

def create_form(
    form: CompiledForm,
    V: list[FunctionSpace],
    msh: Mesh,
    subdomains: dict[IntegralType, list[tuple[int, np.ndarray]]],
    coefficient_map: dict[ufl.Coefficient, Function],
    constant_map: dict[ufl.Constant, Constant],
    entity_maps: Sequence[_EntityMap] | None = None,
) -> Form:
    """Create a Form object from a data-independent compiled form.

    Args:
        form: Compiled ufl form,
        V: List of function spaces associated with the form. Should
            match the number of arguments in the form.
        msh: Mesh to associate form with.
        subdomains: A map from integral type to a list of pairs, where
            each pair corresponds to a subdomain id and the set of of
            integration entities to integrate over. Can be computed with
            {py:func}`dolfinx.fem.compute_integration_domains`.
        coefficient_map: Map from UFL coefficient to function with data.
        constant_map: Map from UFL constant to constant with data.
            to the integration domain ``msh``. The value of the map is
            an array of integers, where the i-th entry is the entity in
            the key mesh.
        entity_maps: Entity maps to support cases where forms involve
            sub-meshes.

    Return:
        A Form object.
    """
    if entity_maps is None:
        _entity_maps = []
    else:
        _entity_maps = [entity_map._cpp_object for entity_map in entity_maps]

    _subdomain_data = subdomains.copy()
    for _, idomain in _subdomain_data.items():
        idomain.sort(key=lambda x: x[0])

    # Extract all coefficients of the compiled form in correct order
    coefficients = {}
    original_coefficients = ufl.algorithms.extract_coefficients(form.ufl_form)
    num_coefficients = form.ufcx_form.num_coefficients
    for c in range(num_coefficients):
        original_index = form.ufcx_form.original_coefficient_positions[c]
        original_coeff = original_coefficients[original_index]
        try:
            coefficients[f"w{c}"] = coefficient_map[original_coeff]._cpp_object
        except KeyError:
            raise RuntimeError(f"Missing coefficient {original_coeff}")

    # Extract all constants of the compiled form in correct order
    # NOTE: Constants are not eliminated
    original_constants = ufl.algorithms.analysis.extract_constants(form.ufl_form)
    num_constants = form.ufcx_form.num_constants
    if num_constants != len(original_constants):
        raise RuntimeError(