Exemple #1
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    def _entity_support_dofs(self):
        esd = {}
        for entity_dim in self.cell.sub_entities.keys():
            beta = self.get_indices()
            zeta = self.get_value_indices()

            entity_cell = self.cell.construct_subelement(entity_dim)
            quad = make_quadrature(entity_cell, (2*numpy.array(self.degree)).tolist())

            eps = 1.e-8  # Is this a safe value?

            result = {}
            for f in self.entity_dofs()[entity_dim].keys():
                # Tabulate basis functions on the facet
                vals, = self.basis_evaluation(0, quad.point_set, entity=(entity_dim, f)).values()
                # Integrate the square of the basis functions on the facet.
                ints = gem.IndexSum(
                    gem.Product(gem.IndexSum(gem.Product(gem.Indexed(vals, beta + zeta),
                                                         gem.Indexed(vals, beta + zeta)), zeta),
                                quad.weight_expression),
                    quad.point_set.indices
                )
                evaluation, = evaluate([gem.ComponentTensor(ints, beta)])
                ints = evaluation.arr.flatten()
                assert evaluation.fids == ()
                result[f] = [dof for dof, i in enumerate(ints) if i > eps]

            esd[entity_dim] = result
        return esd
Exemple #2
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    def _entity_support_dofs(self):
        esd = {}
        for entity_dim in self.cell.sub_entities.keys():
            beta = self.get_indices()
            zeta = self.get_value_indices()

            entity_cell = self.cell.construct_subelement(entity_dim)
            quad = make_quadrature(entity_cell,
                                   (2 * numpy.array(self.degree)).tolist())

            eps = 1.e-8  # Is this a safe value?

            result = {}
            for f in self.entity_dofs()[entity_dim].keys():
                # Tabulate basis functions on the facet
                vals, = self.basis_evaluation(0,
                                              quad.point_set,
                                              entity=(entity_dim, f)).values()
                # Integrate the square of the basis functions on the facet.
                ints = gem.IndexSum(
                    gem.Product(
                        gem.IndexSum(
                            gem.Product(gem.Indexed(vals, beta + zeta),
                                        gem.Indexed(vals, beta + zeta)), zeta),
                        quad.weight_expression), quad.point_set.indices)
                evaluation, = evaluate([gem.ComponentTensor(ints, beta)])
                ints = evaluation.arr.flatten()
                assert evaluation.fids == ()
                result[f] = [dof for dof, i in enumerate(ints) if i > eps]

            esd[entity_dim] = result
        return esd
Exemple #3
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def make_quadrature_element(fiat_ref_cell, degree, scheme="default"):
    """Construct a :class:`QuadratureElement` from a given a reference
    element, degree and scheme.

    :param fiat_ref_cell: The FIAT reference cell to build the
        :class:`QuadratureElement` on.
    :param degree: The degree of polynomial that the rule should
        integrate exactly.
    :param scheme: The quadrature scheme to use - e.g. "default",
        "canonical" or "KMV".
    :returns: The appropriate :class:`QuadratureElement`
    """
    rule = make_quadrature(fiat_ref_cell, degree, scheme)
    return QuadratureElement(fiat_ref_cell, rule)
Exemple #4
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def entity_support_dofs(elem, entity_dim):
    """Return the map of entity id to the degrees of freedom for which
    the corresponding basis functions take non-zero values.

    :arg elem: FInAT finite element
    :arg entity_dim: Dimension of the cell subentity.
    """
    if not hasattr(elem, "_entity_support_dofs"):
        elem._entity_support_dofs = {}
    cache = elem._entity_support_dofs
    try:
        return cache[entity_dim]
    except KeyError:
        pass

    beta = elem.get_indices()
    zeta = elem.get_value_indices()

    entity_cell = elem.cell.construct_subelement(entity_dim)
    quad = make_quadrature(entity_cell,
                           (2 * numpy.array(elem.degree)).tolist())

    eps = 1.e-8  # Is this a safe value?

    result = {}
    for f in elem.entity_dofs()[entity_dim].keys():
        # Tabulate basis functions on the facet
        vals, = itervalues(
            elem.basis_evaluation(0, quad.point_set, entity=(entity_dim, f)))
        # Integrate the square of the basis functions on the facet.
        ints = gem.IndexSum(
            gem.Product(
                gem.IndexSum(
                    gem.Product(gem.Indexed(vals, beta + zeta),
                                gem.Indexed(vals, beta + zeta)), zeta),
                quad.weight_expression), quad.point_set.indices)
        ints = aggressive_unroll(gem.ComponentTensor(ints,
                                                     beta)).array.flatten()
        result[f] = [dof for dof, i in enumerate(ints) if i > eps]

    cache[entity_dim] = result
    return result
Exemple #5
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def dg_injection_kernel(Vf, Vc, ncell):
    from firedrake import Tensor, AssembledVector, TestFunction, TrialFunction
    from firedrake.slate.slac import compile_expression
    macro_builder = MacroKernelBuilder(ScalarType_c, ncell)
    f = ufl.Coefficient(Vf)
    macro_builder.set_coefficients([f])
    macro_builder.set_coordinates(Vf.mesh())

    Vfe = create_element(Vf.ufl_element())
    macro_quadrature_rule = make_quadrature(
        Vfe.cell, estimate_total_polynomial_degree(ufl.inner(f, f)))
    index_cache = {}
    parameters = default_parameters()
    integration_dim, entity_ids = lower_integral_type(Vfe.cell, "cell")
    macro_cfg = dict(interface=macro_builder,
                     ufl_cell=Vf.ufl_cell(),
                     precision=parameters["precision"],
                     integration_dim=integration_dim,
                     entity_ids=entity_ids,
                     index_cache=index_cache,
                     quadrature_rule=macro_quadrature_rule)

    fexpr, = fem.compile_ufl(f, **macro_cfg)
    X = ufl.SpatialCoordinate(Vf.mesh())
    C_a, = fem.compile_ufl(X, **macro_cfg)
    detJ = ufl_utils.preprocess_expression(
        abs(ufl.JacobianDeterminant(f.ufl_domain())))
    macro_detJ, = fem.compile_ufl(detJ, **macro_cfg)

    Vce = create_element(Vc.ufl_element())

    coarse_builder = firedrake_interface.KernelBuilder("cell", "otherwise", 0,
                                                       ScalarType_c)
    coarse_builder.set_coordinates(Vc.mesh())
    argument_multiindices = (Vce.get_indices(), )
    argument_multiindex, = argument_multiindices
    return_variable, = coarse_builder.set_arguments((ufl.TestFunction(Vc), ),
                                                    argument_multiindices)

    integration_dim, entity_ids = lower_integral_type(Vce.cell, "cell")
    # Midpoint quadrature for jacobian on coarse cell.
    quadrature_rule = make_quadrature(Vce.cell, 0)

    coarse_cfg = dict(interface=coarse_builder,
                      ufl_cell=Vc.ufl_cell(),
                      precision=parameters["precision"],
                      integration_dim=integration_dim,
                      entity_ids=entity_ids,
                      index_cache=index_cache,
                      quadrature_rule=quadrature_rule)

    X = ufl.SpatialCoordinate(Vc.mesh())
    K = ufl_utils.preprocess_expression(ufl.JacobianInverse(Vc.mesh()))
    C_0, = fem.compile_ufl(X, **coarse_cfg)
    K, = fem.compile_ufl(K, **coarse_cfg)

    i = gem.Index()
    j = gem.Index()

    C_0 = gem.Indexed(C_0, (j, ))
    C_0 = gem.index_sum(C_0, quadrature_rule.point_set.indices)
    C_a = gem.Indexed(C_a, (j, ))
    X_a = gem.Sum(C_0, gem.Product(gem.Literal(-1), C_a))

    K_ij = gem.Indexed(K, (i, j))
    K_ij = gem.index_sum(K_ij, quadrature_rule.point_set.indices)
    X_a = gem.index_sum(gem.Product(K_ij, X_a), (j, ))
    C_0, = quadrature_rule.point_set.points
    C_0 = gem.Indexed(gem.Literal(C_0), (i, ))
    # fine quad points in coarse reference space.
    X_a = gem.Sum(C_0, gem.Product(gem.Literal(-1), X_a))
    X_a = gem.ComponentTensor(X_a, (i, ))

    # Coarse basis function evaluated at fine quadrature points
    phi_c = fem.fiat_to_ufl(
        Vce.point_evaluation(0, X_a, (Vce.cell.get_dimension(), 0)), 0)

    tensor_indices = tuple(gem.Index(extent=d) for d in f.ufl_shape)

    phi_c = gem.Indexed(phi_c, argument_multiindex + tensor_indices)
    fexpr = gem.Indexed(fexpr, tensor_indices)
    quadrature_weight = macro_quadrature_rule.weight_expression
    expr = gem.Product(gem.IndexSum(gem.Product(phi_c, fexpr), tensor_indices),
                       gem.Product(macro_detJ, quadrature_weight))

    quadrature_indices = macro_builder.indices + macro_quadrature_rule.point_set.indices

    reps = spectral.Integrals([expr], quadrature_indices,
                              argument_multiindices, parameters)
    assignments = spectral.flatten([(return_variable, reps)], index_cache)
    return_variables, expressions = zip(*assignments)
    expressions = impero_utils.preprocess_gem(expressions,
                                              **spectral.finalise_options)
    assignments = list(zip(return_variables, expressions))
    impero_c = impero_utils.compile_gem(assignments,
                                        quadrature_indices +
                                        argument_multiindex,
                                        remove_zeros=True)

    index_names = []

    def name_index(index, name):
        index_names.append((index, name))
        if index in index_cache:
            for multiindex, suffix in zip(index_cache[index],
                                          string.ascii_lowercase):
                name_multiindex(multiindex, name + suffix)

    def name_multiindex(multiindex, name):
        if len(multiindex) == 1:
            name_index(multiindex[0], name)
        else:
            for i, index in enumerate(multiindex):
                name_index(index, name + str(i))

    name_multiindex(quadrature_indices, 'ip')
    for multiindex, name in zip(argument_multiindices, ['j', 'k']):
        name_multiindex(multiindex, name)

    index_names.extend(zip(macro_builder.indices, ["entity"]))
    body = generate_coffee(impero_c, index_names, parameters["precision"],
                           ScalarType_c)

    retarg = ast.Decl(ScalarType_c,
                      ast.Symbol("R", rank=(Vce.space_dimension(), )))
    local_tensor = coarse_builder.local_tensor
    local_tensor.init = ast.ArrayInit(
        numpy.zeros(Vce.space_dimension(), dtype=ScalarType_c))
    body.children.insert(0, local_tensor)
    args = [retarg] + macro_builder.kernel_args + [
        macro_builder.coordinates_arg, coarse_builder.coordinates_arg
    ]

    # Now we have the kernel that computes <f, phi_c>dx_c
    # So now we need to hit it with the inverse mass matrix on dx_c

    u = TrialFunction(Vc)
    v = TestFunction(Vc)
    expr = Tensor(ufl.inner(u, v) * ufl.dx).inv * AssembledVector(
        ufl.Coefficient(Vc))
    Ainv, = compile_expression(expr)
    Ainv = Ainv.kinfo.kernel
    A = ast.Symbol(local_tensor.sym.symbol)
    R = ast.Symbol("R")
    body.children.append(
        ast.FunCall(Ainv.name, R, coarse_builder.coordinates_arg.sym, A))
    from coffee.base import Node
    assert isinstance(Ainv._code, Node)
    return op2.Kernel(ast.Node([
        Ainv._code,
        ast.FunDecl("void",
                    "pyop2_kernel_injection_dg",
                    args,
                    body,
                    pred=["static", "inline"])
    ]),
                      name="pyop2_kernel_injection_dg",
                      cpp=True,
                      include_dirs=Ainv._include_dirs,
                      headers=Ainv._headers)
Exemple #6
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 def quadrature_rule(self):
     integration_cell = self.fiat_cell.construct_subelement(
         self.integration_dim)
     return make_quadrature(integration_cell, self.quadrature_degree)
Exemple #7
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def compile_integral(integral_data, form_data, prefix, parameters,
                     interface=firedrake_interface):
    """Compiles a UFL integral into an assembly kernel.

    :arg integral_data: UFL integral data
    :arg form_data: UFL form data
    :arg prefix: kernel name will start with this string
    :arg parameters: parameters object
    :arg interface: backend module for the kernel interface
    :returns: a kernel constructed by the kernel interface
    """
    if parameters is None:
        parameters = default_parameters()
    else:
        _ = default_parameters()
        _.update(parameters)
        parameters = _

    # Remove these here, they're handled below.
    if parameters.get("quadrature_degree") in ["auto", "default", None, -1, "-1"]:
        del parameters["quadrature_degree"]
    if parameters.get("quadrature_rule") in ["auto", "default", None]:
        del parameters["quadrature_rule"]

    integral_type = integral_data.integral_type
    interior_facet = integral_type.startswith("interior_facet")
    mesh = integral_data.domain
    cell = integral_data.domain.ufl_cell()
    arguments = form_data.preprocessed_form.arguments()
    kernel_name = "%s_%s_integral_%s" % (prefix, integral_type, integral_data.subdomain_id)
    # Handle negative subdomain_id
    kernel_name = kernel_name.replace("-", "_")

    fiat_cell = as_fiat_cell(cell)
    integration_dim, entity_ids = lower_integral_type(fiat_cell, integral_type)

    quadrature_indices = []

    # Dict mapping domains to index in original_form.ufl_domains()
    domain_numbering = form_data.original_form.domain_numbering()
    builder = interface.KernelBuilder(integral_type, integral_data.subdomain_id,
                                      domain_numbering[integral_data.domain])
    argument_multiindices = tuple(builder.create_element(arg.ufl_element()).get_indices()
                                  for arg in arguments)
    return_variables = builder.set_arguments(arguments, argument_multiindices)

    builder.set_coordinates(mesh)

    builder.set_coefficients(integral_data, form_data)

    # Map from UFL FiniteElement objects to multiindices.  This is
    # so we reuse Index instances when evaluating the same coefficient
    # multiple times with the same table.
    #
    # We also use the same dict for the unconcatenate index cache,
    # which maps index objects to tuples of multiindices.  These two
    # caches shall never conflict as their keys have different types
    # (UFL finite elements vs. GEM index objects).
    index_cache = {}

    kernel_cfg = dict(interface=builder,
                      ufl_cell=cell,
                      integral_type=integral_type,
                      precision=parameters["precision"],
                      integration_dim=integration_dim,
                      entity_ids=entity_ids,
                      argument_multiindices=argument_multiindices,
                      index_cache=index_cache)

    mode_irs = collections.OrderedDict()
    for integral in integral_data.integrals:
        params = parameters.copy()
        params.update(integral.metadata())  # integral metadata overrides
        if params.get("quadrature_rule") == "default":
            del params["quadrature_rule"]

        mode = pick_mode(params["mode"])
        mode_irs.setdefault(mode, collections.OrderedDict())

        integrand = ufl.replace(integral.integrand(), form_data.function_replace_map)
        integrand = ufl_utils.split_coefficients(integrand, builder.coefficient_split)

        # Check if the integral has a quad degree attached, otherwise use
        # the estimated polynomial degree attached by compute_form_data
        quadrature_degree = params.get("quadrature_degree",
                                       params["estimated_polynomial_degree"])
        try:
            quadrature_degree = params["quadrature_degree"]
        except KeyError:
            quadrature_degree = params["estimated_polynomial_degree"]
            functions = list(arguments) + [builder.coordinate(mesh)] + list(integral_data.integral_coefficients)
            function_degrees = [f.ufl_function_space().ufl_element().degree() for f in functions]
            if all((asarray(quadrature_degree) > 10 * asarray(degree)).all()
                   for degree in function_degrees):
                logger.warning("Estimated quadrature degree %s more "
                               "than tenfold greater than any "
                               "argument/coefficient degree (max %s)",
                               quadrature_degree, max_degree(function_degrees))

        try:
            quad_rule = params["quadrature_rule"]
        except KeyError:
            integration_cell = fiat_cell.construct_subelement(integration_dim)
            quad_rule = make_quadrature(integration_cell, quadrature_degree)

        if not isinstance(quad_rule, AbstractQuadratureRule):
            raise ValueError("Expected to find a QuadratureRule object, not a %s" %
                             type(quad_rule))

        quadrature_multiindex = quad_rule.point_set.indices
        quadrature_indices.extend(quadrature_multiindex)

        config = kernel_cfg.copy()
        config.update(quadrature_rule=quad_rule)
        expressions = fem.compile_ufl(integrand,
                                      interior_facet=interior_facet,
                                      **config)
        reps = mode.Integrals(expressions, quadrature_multiindex,
                              argument_multiindices, params)
        for var, rep in zip(return_variables, reps):
            mode_irs[mode].setdefault(var, []).append(rep)

    # Finalise mode representations into a set of assignments
    assignments = []
    for mode, var_reps in mode_irs.items():
        assignments.extend(mode.flatten(var_reps.items(), index_cache))

    if assignments:
        return_variables, expressions = zip(*assignments)
    else:
        return_variables = []
        expressions = []

    # Need optimised roots for COFFEE
    options = dict(reduce(operator.and_,
                          [mode.finalise_options.items()
                           for mode in mode_irs.keys()]))
    expressions = impero_utils.preprocess_gem(expressions, **options)
    assignments = list(zip(return_variables, expressions))

    # Look for cell orientations in the IR
    if builder.needs_cell_orientations(expressions):
        builder.require_cell_orientations()

    # Construct ImperoC
    split_argument_indices = tuple(chain(*[var.index_ordering()
                                           for var in return_variables]))
    index_ordering = tuple(quadrature_indices) + split_argument_indices
    try:
        impero_c = impero_utils.compile_gem(assignments, index_ordering, remove_zeros=True)
    except impero_utils.NoopError:
        # No operations, construct empty kernel
        return builder.construct_empty_kernel(kernel_name)

    # Generate COFFEE
    index_names = []

    def name_index(index, name):
        index_names.append((index, name))
        if index in index_cache:
            for multiindex, suffix in zip(index_cache[index],
                                          string.ascii_lowercase):
                name_multiindex(multiindex, name + suffix)

    def name_multiindex(multiindex, name):
        if len(multiindex) == 1:
            name_index(multiindex[0], name)
        else:
            for i, index in enumerate(multiindex):
                name_index(index, name + str(i))

    name_multiindex(quadrature_indices, 'ip')
    for multiindex, name in zip(argument_multiindices, ['j', 'k']):
        name_multiindex(multiindex, name)

    # Construct kernel
    body = generate_coffee(impero_c, index_names, parameters["precision"], expressions, split_argument_indices)

    return builder.construct_kernel(kernel_name, body)
Exemple #8
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def compile_integral(integral_data, form_data, prefix, parameters,
                     interface=firedrake_interface):
    """Compiles a UFL integral into an assembly kernel.

    :arg integral_data: UFL integral data
    :arg form_data: UFL form data
    :arg prefix: kernel name will start with this string
    :arg parameters: parameters object
    :arg interface: backend module for the kernel interface
    :returns: a kernel constructed by the kernel interface
    """
    if parameters is None:
        parameters = default_parameters()
    else:
        _ = default_parameters()
        _.update(parameters)
        parameters = _

    # Remove these here, they're handled below.
    if parameters.get("quadrature_degree") in ["auto", "default", None, -1, "-1"]:
        del parameters["quadrature_degree"]
    if parameters.get("quadrature_rule") in ["auto", "default", None]:
        del parameters["quadrature_rule"]

    integral_type = integral_data.integral_type
    interior_facet = integral_type.startswith("interior_facet")
    mesh = integral_data.domain
    cell = integral_data.domain.ufl_cell()
    arguments = form_data.preprocessed_form.arguments()

    fiat_cell = as_fiat_cell(cell)
    integration_dim, entity_ids = lower_integral_type(fiat_cell, integral_type)

    argument_indices = tuple(tuple(gem.Index(extent=e)
                                   for e in create_element(arg.ufl_element()).index_shape)
                             for arg in arguments)
    flat_argument_indices = tuple(chain(*argument_indices))
    quadrature_indices = []

    # Dict mapping domains to index in original_form.ufl_domains()
    domain_numbering = form_data.original_form.domain_numbering()
    builder = interface.KernelBuilder(integral_type, integral_data.subdomain_id,
                                      domain_numbering[integral_data.domain])
    return_variables = builder.set_arguments(arguments, argument_indices)

    coordinates = ufl_utils.coordinate_coefficient(mesh)
    builder.set_coordinates(coordinates)

    builder.set_coefficients(integral_data, form_data)

    # Map from UFL FiniteElement objects to Index instances.  This is
    # so we reuse Index instances when evaluating the same coefficient
    # multiple times with the same table.  Occurs, for example, if we
    # have multiple integrals here (and the affine coordinate
    # evaluation can be hoisted).
    index_cache = collections.defaultdict(gem.Index)

    kernel_cfg = dict(interface=builder,
                      ufl_cell=cell,
                      precision=parameters["precision"],
                      integration_dim=integration_dim,
                      entity_ids=entity_ids,
                      argument_indices=argument_indices,
                      index_cache=index_cache)

    kernel_cfg["facetarea"] = facetarea_generator(mesh, coordinates, kernel_cfg, integral_type)
    kernel_cfg["cellvolume"] = cellvolume_generator(mesh, coordinates, kernel_cfg)

    irs = []
    for integral in integral_data.integrals:
        params = {}
        # Record per-integral parameters
        params.update(integral.metadata())
        if params.get("quadrature_rule") == "default":
            del params["quadrature_rule"]
        # parameters override per-integral metadata
        params.update(parameters)

        integrand = ufl_utils.replace_coordinates(integral.integrand(), coordinates)
        integrand = ufl_utils.split_coefficients(integrand, builder.coefficient_split)

        # Check if the integral has a quad degree attached, otherwise use
        # the estimated polynomial degree attached by compute_form_data
        quadrature_degree = params.get("quadrature_degree",
                                       params["estimated_polynomial_degree"])
        try:
            quad_rule = params["quadrature_rule"]
        except KeyError:
            integration_cell = fiat_cell.construct_subelement(integration_dim)
            quad_rule = make_quadrature(integration_cell, quadrature_degree)

        if not isinstance(quad_rule, AbstractQuadratureRule):
            raise ValueError("Expected to find a QuadratureRule object, not a %s" %
                             type(quad_rule))

        quadrature_multiindex = quad_rule.point_set.indices
        quadrature_indices += quadrature_multiindex

        config = kernel_cfg.copy()
        config.update(quadrature_rule=quad_rule)
        ir = fem.compile_ufl(integrand, interior_facet=interior_facet, **config)
        if parameters["unroll_indexsum"]:
            def predicate(index):
                return index.extent <= parameters["unroll_indexsum"]
            ir = opt.unroll_indexsum(ir, predicate=predicate)
        ir = [gem.index_sum(expr, quadrature_multiindex) for expr in ir]
        irs.append(ir)

    # Sum the expressions that are part of the same restriction
    ir = list(reduce(gem.Sum, e, gem.Zero()) for e in zip(*irs))

    # Need optimised roots for COFFEE
    ir = impero_utils.preprocess_gem(ir)

    # Look for cell orientations in the IR
    if builder.needs_cell_orientations(ir):
        builder.require_cell_orientations()

    impero_c = impero_utils.compile_gem(return_variables, ir,
                                        tuple(quadrature_indices) + flat_argument_indices,
                                        remove_zeros=True)

    # Generate COFFEE
    index_names = [(si, name + str(n))
                   for index, name in zip(argument_indices, ['j', 'k'])
                   for n, si in enumerate(index)]
    if len(quadrature_indices) == 1:
        index_names.append((quadrature_indices[0], 'ip'))
    else:
        for i, quadrature_index in enumerate(quadrature_indices):
            index_names.append((quadrature_index, 'ip_%d' % i))

    body = generate_coffee(impero_c, index_names, parameters["precision"], ir, flat_argument_indices)

    kernel_name = "%s_%s_integral_%s" % (prefix, integral_type, integral_data.subdomain_id)
    return builder.construct_kernel(kernel_name, body)
Exemple #9
0
 def quadrature_rule(self):
     integration_cell = self.fiat_cell.construct_subelement(self.integration_dim)
     return make_quadrature(integration_cell, self.quadrature_degree)
Exemple #10
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def compile_integral(integral_data,
                     form_data,
                     prefix,
                     parameters,
                     interface=firedrake_interface):
    """Compiles a UFL integral into an assembly kernel.

    :arg integral_data: UFL integral data
    :arg form_data: UFL form data
    :arg prefix: kernel name will start with this string
    :arg parameters: parameters object
    :arg interface: backend module for the kernel interface
    :returns: a kernel constructed by the kernel interface
    """
    if parameters is None:
        parameters = default_parameters()
    else:
        _ = default_parameters()
        _.update(parameters)
        parameters = _

    # Remove these here, they're handled below.
    if parameters.get("quadrature_degree") in [
            "auto", "default", None, -1, "-1"
    ]:
        del parameters["quadrature_degree"]
    if parameters.get("quadrature_rule") in ["auto", "default", None]:
        del parameters["quadrature_rule"]

    integral_type = integral_data.integral_type
    interior_facet = integral_type.startswith("interior_facet")
    mesh = integral_data.domain
    cell = integral_data.domain.ufl_cell()
    arguments = form_data.preprocessed_form.arguments()
    kernel_name = "%s_%s_integral_%s" % (prefix, integral_type,
                                         integral_data.subdomain_id)

    fiat_cell = as_fiat_cell(cell)
    integration_dim, entity_ids = lower_integral_type(fiat_cell, integral_type)

    argument_multiindices = tuple(
        create_element(arg.ufl_element()).get_indices() for arg in arguments)
    argument_indices = tuple(chain(*argument_multiindices))
    quadrature_indices = []

    # Dict mapping domains to index in original_form.ufl_domains()
    domain_numbering = form_data.original_form.domain_numbering()
    builder = interface.KernelBuilder(integral_type,
                                      integral_data.subdomain_id,
                                      domain_numbering[integral_data.domain])
    return_variables = builder.set_arguments(arguments, argument_multiindices)

    coordinates = ufl_utils.coordinate_coefficient(mesh)
    builder.set_coordinates(coordinates)

    builder.set_coefficients(integral_data, form_data)

    # Map from UFL FiniteElement objects to multiindices.  This is
    # so we reuse Index instances when evaluating the same coefficient
    # multiple times with the same table.
    index_cache = {}

    kernel_cfg = dict(interface=builder,
                      ufl_cell=cell,
                      precision=parameters["precision"],
                      integration_dim=integration_dim,
                      entity_ids=entity_ids,
                      argument_multiindices=argument_multiindices,
                      index_cache=index_cache)

    kernel_cfg["facetarea"] = facetarea_generator(mesh, coordinates,
                                                  kernel_cfg, integral_type)
    kernel_cfg["cellvolume"] = cellvolume_generator(mesh, coordinates,
                                                    kernel_cfg)

    mode_irs = collections.OrderedDict()
    for integral in integral_data.integrals:
        params = parameters.copy()
        params.update(integral.metadata())  # integral metadata overrides
        if params.get("quadrature_rule") == "default":
            del params["quadrature_rule"]

        mode = pick_mode(params["mode"])
        mode_irs.setdefault(mode, collections.OrderedDict())

        integrand = ufl_utils.replace_coordinates(integral.integrand(),
                                                  coordinates)
        integrand = ufl.replace(integrand, form_data.function_replace_map)
        integrand = ufl_utils.split_coefficients(integrand,
                                                 builder.coefficient_split)

        # Check if the integral has a quad degree attached, otherwise use
        # the estimated polynomial degree attached by compute_form_data
        quadrature_degree = params.get("quadrature_degree",
                                       params["estimated_polynomial_degree"])
        try:
            quad_rule = params["quadrature_rule"]
        except KeyError:
            integration_cell = fiat_cell.construct_subelement(integration_dim)
            quad_rule = make_quadrature(integration_cell, quadrature_degree)

        if not isinstance(quad_rule, AbstractQuadratureRule):
            raise ValueError(
                "Expected to find a QuadratureRule object, not a %s" %
                type(quad_rule))

        quadrature_multiindex = quad_rule.point_set.indices
        quadrature_indices.extend(quadrature_multiindex)

        config = kernel_cfg.copy()
        config.update(quadrature_rule=quad_rule)
        expressions = fem.compile_ufl(integrand,
                                      interior_facet=interior_facet,
                                      **config)
        reps = mode.Integrals(expressions, quadrature_multiindex,
                              argument_multiindices, params)
        for var, rep in zip(return_variables, reps):
            mode_irs[mode].setdefault(var, []).append(rep)

    # Finalise mode representations into a set of assignments
    assignments = []
    for mode, var_reps in iteritems(mode_irs):
        assignments.extend(mode.flatten(viewitems(var_reps)))

    if assignments:
        return_variables, expressions = zip(*assignments)
    else:
        return_variables = []
        expressions = []

    # Need optimised roots for COFFEE
    options = dict(
        reduce(
            operator.and_,
            [viewitems(mode.finalise_options) for mode in iterkeys(mode_irs)]))
    expressions = impero_utils.preprocess_gem(expressions, **options)
    assignments = list(zip(return_variables, expressions))

    # Look for cell orientations in the IR
    if builder.needs_cell_orientations(expressions):
        builder.require_cell_orientations()

    # Construct ImperoC
    index_ordering = tuple(quadrature_indices) + argument_indices
    try:
        impero_c = impero_utils.compile_gem(assignments,
                                            index_ordering,
                                            remove_zeros=True)
    except impero_utils.NoopError:
        # No operations, construct empty kernel
        return builder.construct_empty_kernel(kernel_name)

    # Generate COFFEE
    index_names = [(si, name + str(n))
                   for index, name in zip(argument_multiindices, ['j', 'k'])
                   for n, si in enumerate(index)]
    if len(quadrature_indices) == 1:
        index_names.append((quadrature_indices[0], 'ip'))
    else:
        for i, quadrature_index in enumerate(quadrature_indices):
            index_names.append((quadrature_index, 'ip_%d' % i))

    # Construct kernel
    body = generate_coffee(impero_c, index_names, parameters["precision"],
                           expressions, argument_indices)

    return builder.construct_kernel(kernel_name, body)
Exemple #11
0
def dg_injection_kernel(Vf, Vc, ncell):
    from firedrake import Tensor, AssembledVector, TestFunction, TrialFunction
    from firedrake.slate.slac import compile_expression
    macro_builder = MacroKernelBuilder(ncell)
    f = ufl.Coefficient(Vf)
    macro_builder.set_coefficients([f])
    macro_builder.set_coordinates(Vf.mesh())

    Vfe = create_element(Vf.ufl_element())
    macro_quadrature_rule = make_quadrature(Vfe.cell, estimate_total_polynomial_degree(ufl.inner(f, f)))
    index_cache = {}
    parameters = default_parameters()
    integration_dim, entity_ids = lower_integral_type(Vfe.cell, "cell")
    macro_cfg = dict(interface=macro_builder,
                     ufl_cell=Vf.ufl_cell(),
                     precision=parameters["precision"],
                     integration_dim=integration_dim,
                     entity_ids=entity_ids,
                     index_cache=index_cache,
                     quadrature_rule=macro_quadrature_rule)

    fexpr, = fem.compile_ufl(f, **macro_cfg)
    X = ufl.SpatialCoordinate(Vf.mesh())
    C_a, = fem.compile_ufl(X, **macro_cfg)
    detJ = ufl_utils.preprocess_expression(abs(ufl.JacobianDeterminant(f.ufl_domain())))
    macro_detJ, = fem.compile_ufl(detJ, **macro_cfg)

    Vce = create_element(Vc.ufl_element())

    coarse_builder = firedrake_interface.KernelBuilder("cell", "otherwise", 0)
    coarse_builder.set_coordinates(Vc.mesh())
    argument_multiindices = (Vce.get_indices(), )
    argument_multiindex, = argument_multiindices
    return_variable, = coarse_builder.set_arguments((ufl.TestFunction(Vc), ), argument_multiindices)

    integration_dim, entity_ids = lower_integral_type(Vce.cell, "cell")
    # Midpoint quadrature for jacobian on coarse cell.
    quadrature_rule = make_quadrature(Vce.cell, 0)

    coarse_cfg = dict(interface=coarse_builder,
                      ufl_cell=Vc.ufl_cell(),
                      precision=parameters["precision"],
                      integration_dim=integration_dim,
                      entity_ids=entity_ids,
                      index_cache=index_cache,
                      quadrature_rule=quadrature_rule)

    X = ufl.SpatialCoordinate(Vc.mesh())
    K = ufl_utils.preprocess_expression(ufl.JacobianInverse(Vc.mesh()))
    C_0, = fem.compile_ufl(X, **coarse_cfg)
    K, = fem.compile_ufl(K, **coarse_cfg)

    i = gem.Index()
    j = gem.Index()

    C_0 = gem.Indexed(C_0, (j, ))
    C_0 = gem.index_sum(C_0, quadrature_rule.point_set.indices)
    C_a = gem.Indexed(C_a, (j, ))
    X_a = gem.Sum(C_0, gem.Product(gem.Literal(-1), C_a))

    K_ij = gem.Indexed(K, (i, j))
    K_ij = gem.index_sum(K_ij, quadrature_rule.point_set.indices)
    X_a = gem.index_sum(gem.Product(K_ij, X_a), (j, ))
    C_0, = quadrature_rule.point_set.points
    C_0 = gem.Indexed(gem.Literal(C_0), (i, ))
    # fine quad points in coarse reference space.
    X_a = gem.Sum(C_0, gem.Product(gem.Literal(-1), X_a))
    X_a = gem.ComponentTensor(X_a, (i, ))

    # Coarse basis function evaluated at fine quadrature points
    phi_c = fem.fiat_to_ufl(Vce.point_evaluation(0, X_a, (Vce.cell.get_dimension(), 0)), 0)

    tensor_indices = tuple(gem.Index(extent=d) for d in f.ufl_shape)

    phi_c = gem.Indexed(phi_c, argument_multiindex + tensor_indices)
    fexpr = gem.Indexed(fexpr, tensor_indices)
    quadrature_weight = macro_quadrature_rule.weight_expression
    expr = gem.Product(gem.IndexSum(gem.Product(phi_c, fexpr), tensor_indices),
                       gem.Product(macro_detJ, quadrature_weight))

    quadrature_indices = macro_builder.indices + macro_quadrature_rule.point_set.indices

    reps = spectral.Integrals([expr], quadrature_indices, argument_multiindices, parameters)
    assignments = spectral.flatten([(return_variable, reps)], index_cache)
    return_variables, expressions = zip(*assignments)
    expressions = impero_utils.preprocess_gem(expressions, **spectral.finalise_options)
    assignments = list(zip(return_variables, expressions))
    impero_c = impero_utils.compile_gem(assignments, quadrature_indices + argument_multiindex,
                                        remove_zeros=True)

    index_names = []

    def name_index(index, name):
        index_names.append((index, name))
        if index in index_cache:
            for multiindex, suffix in zip(index_cache[index],
                                          string.ascii_lowercase):
                name_multiindex(multiindex, name + suffix)

    def name_multiindex(multiindex, name):
        if len(multiindex) == 1:
            name_index(multiindex[0], name)
        else:
            for i, index in enumerate(multiindex):
                name_index(index, name + str(i))

    name_multiindex(quadrature_indices, 'ip')
    for multiindex, name in zip(argument_multiindices, ['j', 'k']):
        name_multiindex(multiindex, name)

    index_names.extend(zip(macro_builder.indices, ["entity"]))
    body = generate_coffee(impero_c, index_names, parameters["precision"])

    retarg = ast.Decl(SCALAR_TYPE, ast.Symbol("R", rank=(Vce.space_dimension(), )))
    local_tensor = coarse_builder.local_tensor
    local_tensor.init = ast.ArrayInit(numpy.zeros(Vce.space_dimension(), dtype=SCALAR_TYPE))
    body.children.insert(0, local_tensor)
    args = [retarg] + macro_builder.kernel_args + [macro_builder.coordinates_arg,
                                                   coarse_builder.coordinates_arg]

    # Now we have the kernel that computes <f, phi_c>dx_c
    # So now we need to hit it with the inverse mass matrix on dx_c

    u = TrialFunction(Vc)
    v = TestFunction(Vc)
    expr = Tensor(ufl.inner(u, v)*ufl.dx).inv * AssembledVector(ufl.Coefficient(Vc))
    Ainv, = compile_expression(expr)
    Ainv = Ainv.kinfo.kernel
    A = ast.Symbol(local_tensor.sym.symbol)
    R = ast.Symbol("R")
    body.children.append(ast.FunCall(Ainv.name, R, coarse_builder.coordinates_arg.sym, A))
    from coffee.base import Node
    assert isinstance(Ainv._code, Node)
    return op2.Kernel(ast.Node([Ainv._code,
                                ast.FunDecl("void", "pyop2_kernel_injection_dg", args, body,
                                            pred=["static", "inline"])]),
                      name="pyop2_kernel_injection_dg",
                      cpp=True,
                      include_dirs=Ainv._include_dirs,
                      headers=Ainv._headers)
Exemple #12
0
 def __init__(self, cell, degree, scheme="default"):
     self.cell = cell
     self._rule = make_quadrature(cell, degree, scheme)