Source code for ffc.representation

# -*- coding: utf-8 -*-
"""
Compiler stage 2: Code representation
-------------------------------------

This module computes intermediate representations of forms,
elements and dofmaps. For each UFC function, we extract the
data needed for code generation at a later stage.

The representation should conform strictly to the naming and
order of functions in UFC. Thus, for code generation of the
function "foo", one should only need to use the data stored
in the intermediate representation under the key "foo".
"""

# Copyright (C) 2009-2016 Anders Logg, Martin Sandve Alnæs, Marie E. Rognes,
# Kristian B. Oelgaard, and others
#
# This file is part of FFC.
#
# FFC is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# FFC is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with FFC. If not, see <http://www.gnu.org/licenses/>.

# Python modules
from itertools import chain
import numpy

# Import UFL
import ufl

# FFC modules
from ffc.utils import compute_permutations, product
from ffc.log import info, error, begin, end, debug_ir, warning
from ffc.fiatinterface import create_element, reference_cell
from ffc.mixedelement import MixedElement
from ffc.enrichedelement import EnrichedElement, SpaceOfReals
from ffc.fiatinterface import HDivTrace
from ffc.quadratureelement import QuadratureElement
from ffc.cpp import set_float_formatting
from ffc.cpp import make_classname, make_integral_classname


# List of supported integral types
ufc_integral_types = ("cell",
                      "exterior_facet",
                      "interior_facet",
                      "vertex",
                      "custom",
                      "cutcell",
                      "interface",
                      "overlap")


[docs]def pick_representation(representation): "Return one of the specialized code generation modules from a representation string." if representation == "quadrature": from ffc import quadrature as r elif representation == "tensor": from ffc import tensor as r elif representation == "uflacs": from ffc import uflacs as r elif representation == "tsfc": from ffc import tsfc as r else: error("Unknown representation: %s" % str(representation)) return r
[docs]def make_finite_element_jit_classname(ufl_element, parameters): from ffc.jitcompiler import compute_jit_prefix # FIXME circular file dependency kind, prefix = compute_jit_prefix(ufl_element, parameters) return make_classname(prefix, "finite_element", "main")
[docs]def make_dofmap_jit_classname(ufl_element, parameters): from ffc.jitcompiler import compute_jit_prefix # FIXME circular file dependency kind, prefix = compute_jit_prefix(ufl_element, parameters) return make_classname(prefix, "dofmap", "main")
[docs]def make_coordinate_mapping_jit_classname(ufl_mesh, parameters): from ffc.jitcompiler import compute_jit_prefix # FIXME circular file dependency kind, prefix = compute_jit_prefix(ufl_mesh, parameters, kind="coordinate_mapping") return make_classname(prefix, "coordinate_mapping", "main")
[docs]def make_all_element_classnames(prefix, elements, coordinate_elements, element_numbers, parameters, jit): if jit: # Make unique classnames to match separately jit-compiled # module classnames = { "finite_element": { e: make_finite_element_jit_classname(e, parameters) for e in elements }, "dofmap": { e: make_dofmap_jit_classname(e, parameters) for e in elements }, "coordinate_mapping": { e: make_coordinate_mapping_jit_classname(e, parameters) for e in coordinate_elements }, } else: # Make unique classnames only within this module (using a # shared prefix and element numbers that are only unique # within this module) classnames = { "finite_element": { e: make_classname(prefix, "finite_element", element_numbers[e]) for e in elements }, "dofmap": { e: make_classname(prefix, "dofmap", element_numbers[e]) for e in elements }, "coordinate_mapping": { e: make_classname(prefix, "coordinate_mapping", element_numbers[e]) for e in coordinate_elements }, } return classnames
[docs]def compute_ir(analysis, prefix, parameters, jit=False): "Compute intermediate representation." begin("Compiler stage 2: Computing intermediate representation") # Set code generation parameters (this is not actually a 'formatting' # parameter, used for table value clamping as well) # FIXME: Global state?! set_float_formatting(parameters["precision"]) # Extract data from analysis form_datas, elements, element_numbers, coordinate_elements = analysis # Construct classnames for all element objects and coordinate mappings classnames = make_all_element_classnames(prefix, elements, coordinate_elements, element_numbers, parameters, jit) # Skip processing elements if jitting forms # NB! it's important that this happens _after_ the element numbers and classnames # above have been created. if jit and form_datas: # While we may get multiple forms during command line action, # not so during jit assert len(form_datas) == 1, "Expecting only one form data instance during jit." # Drop some processing elements = [] coordinate_elements = [] elif jit and coordinate_elements: # While we may get multiple coordinate elements during command # line action, or during form jit, not so during coordinate # mapping jit assert len(coordinate_elements) == 1, "Expecting only one form data instance during jit." # Drop some processing elements = [] elif jit and elements: # Assuming a topological sorting of the elements, # only process the last (main) element from here on elements = [elements[-1]] # Compute representation of elements info("Computing representation of %d elements" % len(elements)) ir_elements = [_compute_element_ir(e, element_numbers, classnames, jit) for e in elements] # Compute representation of dofmaps info("Computing representation of %d dofmaps" % len(elements)) ir_dofmaps = [_compute_dofmap_ir(e, element_numbers, classnames, jit) for e in elements] # Compute representation of coordinate mappings info("Computing representation of %d coordinate mappings" % len(coordinate_elements)) ir_coordinate_mappings = [_compute_coordinate_mapping_ir(e, element_numbers, classnames, jit) for e in coordinate_elements] # Compute and flatten representation of integrals info("Computing representation of integrals") irs = [_compute_integral_ir(fd, form_id, prefix, element_numbers, classnames, parameters, jit) for (form_id, fd) in enumerate(form_datas)] ir_integrals = list(chain(*irs)) # Compute representation of forms info("Computing representation of forms") ir_forms = [_compute_form_ir(fd, form_id, prefix, element_numbers, classnames, parameters, jit) for (form_id, fd) in enumerate(form_datas)] end() return ir_elements, ir_dofmaps, ir_coordinate_mappings, ir_integrals, ir_forms
def _compute_element_ir(ufl_element, element_numbers, classnames, jit): "Compute intermediate representation of element." # Create FIAT element fiat_element = create_element(ufl_element) cell = ufl_element.cell() cellname = cell.cellname() # Store id ir = {"id": element_numbers[ufl_element]} ir["classname"] = classnames["finite_element"][ufl_element] # Remember jit status ir["jit"] = jit # Compute data for each function ir["signature"] = repr(ufl_element) ir["cell_shape"] = cellname ir["topological_dimension"] = cell.topological_dimension() ir["geometric_dimension"] = cell.geometric_dimension() ir["space_dimension"] = fiat_element.space_dimension() ir["value_shape"] = ufl_element.value_shape() ir["reference_value_shape"] = ufl_element.reference_value_shape() ir["degree"] = ufl_element.degree() ir["family"] = ufl_element.family() ir["evaluate_basis"] = _evaluate_basis(ufl_element, fiat_element) ir["evaluate_dof"] = _evaluate_dof(ufl_element, fiat_element) ir["interpolate_vertex_values"] = _interpolate_vertex_values(ufl_element, fiat_element) ir["tabulate_dof_coordinates"] = _tabulate_dof_coordinates(ufl_element, fiat_element) ir["num_sub_elements"] = ufl_element.num_sub_elements() ir["create_sub_element"] = [classnames["finite_element"][e] for e in ufl_element.sub_elements()] # debug_ir(ir, "finite_element") return ir def _compute_dofmap_ir(ufl_element, element_numbers, classnames, jit=False): "Compute intermediate representation of dofmap." # Create FIAT element fiat_element = create_element(ufl_element) cell = ufl_element.cell() cellname = cell.cellname() # Precompute repeatedly used items num_dofs_per_entity = _num_dofs_per_entity(fiat_element) entity_dofs = fiat_element.entity_dofs() facet_dofs = _tabulate_facet_dofs(fiat_element, cell) entity_closure_dofs, num_dofs_per_entity_closure = \ _tabulate_entity_closure_dofs(fiat_element, cell) # Store id ir = {"id": element_numbers[ufl_element]} ir["classname"] = classnames["dofmap"][ufl_element] # Remember jit status ir["jit"] = jit # Compute data for each function ir["signature"] = "FFC dofmap for " + repr(ufl_element) ir["needs_mesh_entities"] = _needs_mesh_entities(fiat_element) ir["topological_dimension"] = cell.topological_dimension() ir["geometric_dimension"] = cell.geometric_dimension() ir["global_dimension"] = _global_dimension(fiat_element) ir["num_element_dofs"] = fiat_element.space_dimension() ir["num_facet_dofs"] = len(facet_dofs[0]) ir["num_entity_dofs"] = num_dofs_per_entity ir["num_entity_closure_dofs"] = num_dofs_per_entity_closure ir["tabulate_dofs"] = _tabulate_dofs(fiat_element, cell) ir["tabulate_facet_dofs"] = facet_dofs ir["tabulate_entity_dofs"] = (entity_dofs, num_dofs_per_entity) ir["tabulate_entity_closure_dofs"] = (entity_closure_dofs, entity_dofs, num_dofs_per_entity) ir["num_sub_dofmaps"] = ufl_element.num_sub_elements() ir["create_sub_dofmap"] = [classnames["dofmap"][e] for e in ufl_element.sub_elements()] return ir _midpoints = { "interval": (0.5,), "triangle": (1.0 / 3.0, 1.0 / 3.0), "tetrahedron": (0.25, 0.25, 0.25), "quadrilateral": (0.5, 0.5), "hexahedron": (0.5, 0.5, 0.5), }
[docs]def cell_midpoint(cell): # TODO: Is this defined somewhere more central where we can get it from? return _midpoints[cell.cellname()]
def _tabulate_coordinate_mapping_basis(ufl_element): # TODO: Move this function to a table generation module? # Get scalar element, assuming coordinates are represented # with a VectorElement of scalar subelements selement = ufl_element.sub_elements()[0] fiat_element = create_element(selement) cell = selement.cell() tdim = cell.topological_dimension() tables = {} # Get points origo = (0.0,) * tdim midpoint = cell_midpoint(cell) # Tabulate basis t0 = fiat_element.tabulate(1, [origo]) tm = fiat_element.tabulate(1, [midpoint]) # Get basis values at cell origo tables["x0"] = t0[(0,) * tdim][:, 0] # Get basis values at cell midpoint tables["xm"] = tm[(0,) * tdim][:, 0] # Single direction derivatives, e.g. [(1,0), (0,1)] in 2d derivatives = [(0,) * i + (1,) + (0,) * (tdim - 1 - i) for i in range(tdim)] # Get basis derivative values at cell origo tables["J0"] = numpy.asarray([t0[d][:, 0] for d in derivatives]) # Get basis derivative values at cell midpoint tables["Jm"] = numpy.asarray([tm[d][:, 0] for d in derivatives]) return tables def _compute_coordinate_mapping_ir(ufl_coordinate_element, element_numbers, classnames, jit=False): "Compute intermediate representation of coordinate mapping." cell = ufl_coordinate_element.cell() cellname = cell.cellname() assert ufl_coordinate_element.value_shape() == (cell.geometric_dimension(),) # Compute element values via fiat element tables = _tabulate_coordinate_mapping_basis(ufl_coordinate_element) # Store id ir = {"id": element_numbers[ufl_coordinate_element]} ir["classname"] = classnames["coordinate_mapping"][ufl_coordinate_element] # Remember jit status ir["jit"] = jit # Compute data for each function ir["signature"] = "FFC coordinate_mapping from " + repr(ufl_coordinate_element) ir["cell_shape"] = cellname ir["topological_dimension"] = cell.topological_dimension() ir["geometric_dimension"] = ufl_coordinate_element.value_size() ir["create_coordinate_finite_element"] = \ classnames["finite_element"][ufl_coordinate_element] ir["create_coordinate_dofmap"] = \ classnames["dofmap"][ufl_coordinate_element] ir["compute_physical_coordinates"] = None # currently unused, corresponds to function name ir["compute_reference_coordinates"] = None # currently unused, corresponds to function name ir["compute_jacobians"] = None # currently unused, corresponds to function name ir["compute_jacobian_determinants"] = None # currently unused, corresponds to function name ir["compute_jacobian_inverses"] = None # currently unused, corresponds to function name ir["compute_geometry"] = None # currently unused, corresponds to function name # NB! The entries below breaks the pattern of using ir keywords == code keywords, # which I personally don't find very useful anyway (martinal). # Store tables and other coordinate element data ir["tables"] = tables ir["coordinate_element_degree"] = ufl_coordinate_element.degree() ir["num_scalar_coordinate_element_dofs"] = tables["x0"].shape[0] # Get classnames for coordinate element and its scalar subelement: ir["coordinate_finite_element_classname"] = \ classnames["finite_element"][ufl_coordinate_element] ir["scalar_coordinate_finite_element_classname"] = \ classnames["finite_element"][ufl_coordinate_element.sub_elements()[0]] return ir def _global_dimension(fiat_element): "Compute intermediate representation for global_dimension." if not isinstance(fiat_element, MixedElement): if isinstance(fiat_element, SpaceOfReals): return ([], 1) return (_num_dofs_per_entity(fiat_element), 0) elements = [] reals = [] num_reals = 0 for (i, e) in enumerate(fiat_element.elements()): if not isinstance(e, SpaceOfReals): elements += [e] else: num_reals += 1 fiat_element = MixedElement(elements) return (_num_dofs_per_entity(fiat_element), num_reals) def _needs_mesh_entities(fiat_element): "Compute intermediate representation for needs_mesh_entities." # Note: The dof map for Real elements does not depend on the mesh num_dofs_per_entity = _num_dofs_per_entity(fiat_element) if isinstance(fiat_element, SpaceOfReals): return [False for d in num_dofs_per_entity] else: return [d > 0 for d in num_dofs_per_entity] def _compute_integral_ir(form_data, form_id, prefix, element_numbers, classnames, parameters, jit): "Compute intermediate represention for form integrals." # For consistency, all jit objects now have classnames with postfix "main" if jit: assert form_id == 0 form_id = "main" irs = [] # Iterate over integrals for itg_data in form_data.integral_data: # Select representation # TODO: Is it possible to detach this metadata from # IntegralData? It's a bit strange from the ufl side. r = pick_representation(itg_data.metadata["representation"]) # Compute representation ir = r.compute_integral_ir(itg_data, form_data, form_id, # FIXME: Can we remove this? element_numbers, classnames, parameters) # Build classname ir["classname"] = make_integral_classname(prefix, itg_data.integral_type, form_id, itg_data.subdomain_id) ir["classnames"] = classnames # FIXME XXX: Use this everywhere needed? # Storing prefix here for reconstruction of classnames on code # generation side ir["prefix"] = prefix # FIXME: Drop this? # Store metadata for later reference (eg. printing as comment) # NOTE: We make a commitment not to modify it! ir["integrals_metadata"] = itg_data.metadata ir["integral_metadata"] = [integral.metadata() for integral in itg_data.integrals] # Append representation irs.append(ir) return irs def _compute_form_ir(form_data, form_id, prefix, element_numbers, classnames, parameters, jit=False): "Compute intermediate representation of form." # For consistency, all jit objects now have classnames with postfix "main" if jit: assert form_id == 0 form_id = "main" # Store id ir = {"id": form_id} # Storing prefix here for reconstruction of classnames on code # generation side ir["prefix"] = prefix # Remember jit status ir["jit"] = jit # Compute common data ir["classname"] = make_classname(prefix, "form", form_id) # ir["members"] = None # unused # ir["constructor"] = None # unused # ir["destructor"] = None # unused ir["signature"] = form_data.original_form.signature() ir["rank"] = len(form_data.original_form.arguments()) ir["num_coefficients"] = len(form_data.reduced_coefficients) ir["original_coefficient_position"] = form_data.original_coefficient_positions # TODO: Remove create_coordinate_{finite_element,dofmap} and # access through coordinate_mapping instead in dolfin, when that's # in place ir["create_coordinate_finite_element"] = [ classnames["finite_element"][e] for e in form_data.coordinate_elements ] ir["create_coordinate_dofmap"] = [ classnames["dofmap"][e] for e in form_data.coordinate_elements ] ir["create_coordinate_mapping"] = [ classnames["coordinate_mapping"][e] for e in form_data.coordinate_elements ] ir["create_finite_element"] = [ classnames["finite_element"][e] for e in form_data.argument_elements + form_data.coefficient_elements ] ir["create_dofmap"] = [ classnames["dofmap"][e] for e in form_data.argument_elements + form_data.coefficient_elements ] # Create integral ids and names using form prefix # (integrals are always generated as part of form so don't get # their own prefix) for integral_type in ufc_integral_types: ir["max_%s_subdomain_id" % integral_type] = \ form_data.max_subdomain_ids.get(integral_type, 0) ir["has_%s_integrals" % integral_type] = \ _has_foo_integrals(prefix, form_id, integral_type, form_data) ir["create_%s_integral" % integral_type] = \ _create_foo_integral(prefix, form_id, integral_type, form_data) ir["create_default_%s_integral" % integral_type] = \ _create_default_foo_integral(prefix, form_id, integral_type, form_data) return ir # --- Computation of intermediate representation for non-trivial functions --- def _generate_reference_offsets(fiat_element, offset=0): """Generate offsets: i.e value offset for each basis function relative to a reference element representation.""" if isinstance(fiat_element, MixedElement): offsets = [] for e in fiat_element.elements(): offsets += _generate_reference_offsets(e, offset) # NB! This is the fiat element and therefore value_shape # means reference_value_shape offset += product(e.value_shape()) return offsets elif isinstance(fiat_element, EnrichedElement): offsets = [] for e in fiat_element.elements(): offsets += _generate_reference_offsets(e, offset) return offsets else: return [offset] * fiat_element.space_dimension() def _generate_physical_offsets(ufl_element, offset=0): """Generate offsets: i.e value offset for each basis function relative to a physical element representation.""" cell = ufl_element.cell() gdim = cell.geometric_dimension() tdim = cell.topological_dimension() # Refer to reference if gdim == tdim. This is a hack to support # more stuff (in particular restricted elements) if gdim == tdim: return _generate_reference_offsets(create_element(ufl_element)) if isinstance(ufl_element, ufl.MixedElement): offsets = [] for e in ufl_element.sub_elements(): offsets += _generate_physical_offsets(e, offset) # e is a ufl element, so value_size means the physical value size offset += e.value_size() return offsets elif isinstance(ufl_element, ufl.EnrichedElement): offsets = [] for e in ufl_element._elements: # TODO: Avoid private member access offsets += _generate_physical_offsets(e, offset) return offsets elif isinstance(ufl_element, ufl.FiniteElement): fiat_element = create_element(ufl_element) return [offset] * fiat_element.space_dimension() else: raise NotImplementedError("This element combination is not implemented") def _generate_offsets(ufl_element, reference_offset=0, physical_offset=0): """Generate offsets: i.e value offset for each basis function relative to a physical element representation.""" cell = ufl_element.cell() gdim = cell.geometric_dimension() tdim = cell.topological_dimension() if isinstance(ufl_element, ufl.MixedElement): offsets = [] for e in ufl_element.sub_elements(): offsets += _generate_offsets(e, reference_offset, physical_offset) # e is a ufl element, so value_size means the physical value size reference_offset += e.reference_value_size() physical_offset += e.value_size() return offsets elif isinstance(ufl_element, ufl.EnrichedElement): offsets = [] for e in ufl_element._elements: # TODO: Avoid private member access offsets += _generate_offsets(e, reference_offset, physical_offset) return offsets elif isinstance(ufl_element, ufl.FiniteElement): fiat_element = create_element(ufl_element) return [(reference_offset, physical_offset)] * fiat_element.space_dimension() else: # TODO: Support RestrictedElement, QuadratureElement, # TensorProductElement, etc.! and replace # _generate_{physical|reference}_offsets with this # function. raise NotImplementedError("This element combination is not implemented") def _evaluate_dof(ufl_element, fiat_element): "Compute intermediate representation of evaluate_dof." cell = ufl_element.cell() return {"mappings": fiat_element.mapping(), "reference_value_size": ufl_element.reference_value_size(), "physical_value_size": ufl_element.value_size(), "geometric_dimension": cell.geometric_dimension(), "topological_dimension": cell.topological_dimension(), "dofs": [L.pt_dict if L else None for L in fiat_element.dual_basis()], "physical_offsets": _generate_physical_offsets(ufl_element)} def _extract_elements(fiat_element): new_elements = [] if isinstance(fiat_element, (MixedElement, EnrichedElement)): for e in fiat_element.elements(): new_elements += _extract_elements(e) else: new_elements.append(fiat_element) return new_elements def _evaluate_basis(ufl_element, fiat_element): "Compute intermediate representation for evaluate_basis." cell = ufl_element.cell() cellname = cell.cellname() # Handle Mixed and EnrichedElements by extracting 'sub' elements. elements = _extract_elements(fiat_element) physical_offsets = _generate_physical_offsets(ufl_element) reference_offsets = _generate_reference_offsets(fiat_element) mappings = fiat_element.mapping() # This function is evidently not implemented for TensorElements for e in elements: if (len(e.value_shape()) > 1) and (e.num_sub_elements() != 1): return "Function not supported/implemented for TensorElements." # Handle QuadratureElement, not supported because the basis is # only defined at the dof coordinates where the value is 1, so not # very interesting. for e in elements: if isinstance(e, QuadratureElement): return "Function not supported/implemented for QuadratureElement." if isinstance(e, HDivTrace): return "Function not supported for Trace elements" # Initialise data with 'global' values. data = {"reference_value_size": ufl_element.reference_value_size(), "physical_value_size": ufl_element.value_size(), "cellname": cellname, "topological_dimension": cell.topological_dimension(), "geometric_dimension": cell.geometric_dimension(), "space_dimension": fiat_element.space_dimension(), "needs_oriented": needs_oriented_jacobian(fiat_element), "max_degree": max([e.degree() for e in elements]) } # Loop element and space dimensions to generate dof data. dof = 0 dofs_data = [] for e in elements: num_components = product(e.value_shape()) coeffs = e.get_coeffs() num_expansion_members = e.get_num_members(e.degree()) dmats = e.dmats() # Extracted parts of dd below that are common for the element # here. These dict entries are added to each dof_data dict # for each dof, because that's what the code generation # implementation expects. If the code generation needs this # structure to be optimized in the future, we can store this # data for each subelement instead of for each dof. subelement_data = { "embedded_degree": e.degree(), "num_components": num_components, "dmats": dmats, "num_expansion_members": num_expansion_members, } value_rank = len(e.value_shape()) for i in range(e.space_dimension()): if num_components == 1: coefficients = [coeffs[i]] elif value_rank == 1: # Handle coefficients for vector valued basis elements # [Raviart-Thomas, Brezzi-Douglas-Marini (BDM)]. coefficients = [coeffs[i][c] for c in range(num_components)] elif value_rank == 2: # Handle coefficients for tensor valued basis elements. # [Regge] coefficients = [coeffs[i][p][q] for p in range(e.value_shape()[0]) for q in range(e.value_shape()[1])] else: error("Unknown situation with num_components > 1") dof_data = { "coeffs": coefficients, "mapping": mappings[dof], "physical_offset": physical_offsets[dof], "reference_offset": reference_offsets[dof], } # Still storing element data in dd to avoid rewriting dependent code dof_data.update(subelement_data) # This list will hold one dd dict for each dof dofs_data.append(dof_data) dof += 1 data["dofs_data"] = dofs_data return data def _tabulate_dof_coordinates(ufl_element, element): "Compute intermediate representation of tabulate_dof_coordinates." if uses_integral_moments(element): return {} # Bail out if any dual basis member is missing (element is not nodal), # this is strictly not necessary but simpler if any(L is None for L in element.dual_basis()): return {} cell = ufl_element.cell() data = {} data["tdim"] = cell.topological_dimension() data["gdim"] = cell.geometric_dimension() data["points"] = [sorted(L.pt_dict.keys())[0] for L in element.dual_basis()] return data def _tabulate_dofs(element, cell): "Compute intermediate representation of tabulate_dofs." if isinstance(element, SpaceOfReals): return None # Extract number of dofs per entity for each element elements = all_elements(element) num_dofs_per_element = [_num_dofs_per_entity(e) for e in elements] # Extract local dof numbers per entity for each element all_entity_dofs = [e.entity_dofs() for e in elements] dofs_per_element = [[[list(dofs[dim][entity]) for entity in sorted(dofs[dim].keys())] for dim in sorted(dofs.keys())] for dofs in all_entity_dofs] # Check whether we need offset multiple_entities = any([sum(n > 0 for n in num_dofs) - 1 for num_dofs in num_dofs_per_element]) need_offset = len(elements) > 1 or multiple_entities num_dofs_per_element = [e.space_dimension() for e in elements] # Handle global "elements" fakes = [isinstance(e, SpaceOfReals) for e in elements] return (dofs_per_element, num_dofs_per_element, need_offset, fakes) def _tabulate_facet_dofs(element, cell): "Compute intermediate representation of tabulate_facet_dofs." # Compute incidences incidence = __compute_incidence(cell.topological_dimension()) # Get topological dimension D = max([pair[0][0] for pair in incidence]) # Get the number of facets num_facets = cell.num_facets() # Find out which entities are incident to each facet incident = num_facets * [None] for facet in range(num_facets): incident[facet] = [pair[1] for pair in incidence if incidence[pair] is True and pair[0] == (D - 1, facet)] # Make list of dofs facet_dofs = [] entity_dofs = element.entity_dofs() for facet in range(num_facets): facet_dofs += [[]] for dim in entity_dofs: for entity in entity_dofs[dim]: if (dim, entity) in incident[facet]: facet_dofs[facet] += entity_dofs[dim][entity] facet_dofs[facet].sort() return facet_dofs def _tabulate_entity_closure_dofs(element, cell): "Compute intermediate representation of tabulate_entity_closure_dofs." # Compute incidences incidence = __compute_incidence(cell.topological_dimension()) # Get topological dimension D = max([pair[0][0] for pair in incidence]) entity_dofs = element.entity_dofs() entity_closure_dofs = {} for d0 in range(D + 1): # Find out which entities are incident to each entity of dim d0 incident = {} for e0 in entity_dofs[d0]: incident[(d0, e0)] = [pair[1] for pair in incidence if incidence[pair] is True and pair[0] == (d0, e0)] # Make list of dofs for e0 in entity_dofs[d0]: dofs = [] for d1 in entity_dofs: for e1 in entity_dofs[d1]: if (d1, e1) in incident[(d0, e0)]: dofs += entity_dofs[d1][e1] entity_closure_dofs[(d0, e0)] = sorted(dofs) num_entity_closure_dofs = [max(len(dofs) for (d, e), dofs in entity_closure_dofs.items() if d == dim) for dim in range(D + 1)] return entity_closure_dofs, num_entity_closure_dofs def _interpolate_vertex_values(ufl_element, fiat_element): "Compute intermediate representation of interpolate_vertex_values." # Check for QuadratureElement for e in all_elements(fiat_element): if isinstance(e, QuadratureElement): return "Function is not supported/implemented for QuadratureElement." if isinstance(e, HDivTrace): return "Function is not implemented for HDivTrace." cell = ufl_element.cell() cellname = cell.cellname() tdim = cell.topological_dimension() gdim = cell.geometric_dimension() ir = {} ir["geometric_dimension"] = gdim ir["topological_dimension"] = tdim # Check whether computing the Jacobian is necessary mappings = fiat_element.mapping() ir["needs_jacobian"] = any("piola" in m for m in mappings) ir["needs_oriented"] = needs_oriented_jacobian(fiat_element) # See note in _evaluate_dofs ir["reference_value_size"] = ufl_element.reference_value_size() ir["physical_value_size"] = ufl_element.value_size() # Get vertices of reference cell fiat_cell = reference_cell(cellname) vertices = fiat_cell.get_vertices() # Compute data for each constituent element all_fiat_elm = all_elements(fiat_element) ir["element_data"] = [ { # NB! value_shape of fiat element e means reference_value_shape "reference_value_size": product(e.value_shape()), # FIXME: THIS IS A BUG: "physical_value_size": product(e.value_shape()), # FIXME: Get from corresponding ufl element? "basis_values": e.tabulate(0, vertices)[(0,) * tdim].transpose(), "mapping": e.mapping()[0], "space_dim": e.space_dimension(), } for e in all_fiat_elm] # FIXME: Temporary hack! if len(ir["element_data"]) == 1: ir["element_data"][0]["physical_value_size"] = ir["physical_value_size"] # Consistency check, related to note in _evaluate_dofs # This will fail for e.g. (RT1 x DG0) on a manifold because of the above bug if sum(data["physical_value_size"] for data in ir["element_data"]) != ir["physical_value_size"]: ir = "Failed to set physical value size correctly for subelements." elif sum(data["reference_value_size"] for data in ir["element_data"]) != ir["reference_value_size"]: ir = "Failed to set reference value size correctly for subelements." return ir def _has_foo_integrals(prefix, form_id, integral_type, form_data): "Compute intermediate representation of has_foo_integrals." v = (form_data.max_subdomain_ids.get(integral_type, 0) > 0 or _create_default_foo_integral(prefix, form_id, integral_type, form_data) is not None) return bool(v) def _create_foo_integral(prefix, form_id, integral_type, form_data): "Compute intermediate representation of create_foo_integral." subdomain_ids = [itg_data.subdomain_id for itg_data in form_data.integral_data if (itg_data.integral_type == integral_type and isinstance(itg_data.subdomain_id, int))] classnames = [make_integral_classname(prefix, integral_type, form_id, subdomain_id) for subdomain_id in subdomain_ids] return subdomain_ids, classnames def _create_default_foo_integral(prefix, form_id, integral_type, form_data): "Compute intermediate representation of create_default_foo_integral." itg_data = [itg_data for itg_data in form_data.integral_data if (itg_data.integral_type == integral_type and itg_data.subdomain_id == "otherwise")] if len(itg_data) > 1: error("Expecting at most one default integral of each type.") if itg_data: classname = make_integral_classname(prefix, integral_type, form_id, "otherwise") return classname else: return None #--- Utility functions ---
[docs]def all_elements(fiat_element): if isinstance(fiat_element, MixedElement): return fiat_element.elements() return [fiat_element]
def _num_dofs_per_entity(fiat_element): """ Compute list of integers representing the number of dofs associated with a single mesh entity. Example: Lagrange of degree 3 on triangle: [1, 2, 1] """ entity_dofs = fiat_element.entity_dofs() return [len(entity_dofs[e][0]) for e in range(len(entity_dofs.keys()))] # These two are copied from old ffc def __compute_incidence(D): "Compute which entities are incident with which" # Compute the incident vertices for each entity sub_simplices = [] for dim in range(D + 1): sub_simplices += [__compute_sub_simplices(D, dim)] # Check which entities are incident, d0 --> d1 for d0 >= d1 incidence = {} for d0 in range(0, D + 1): for i0 in range(len(sub_simplices[d0])): for d1 in range(d0 + 1): for i1 in range(len(sub_simplices[d1])): incidence[((d0, i0), (d1, i1))] = all(v in sub_simplices[d0][i0] for v in sub_simplices[d1][i1]) return incidence def __compute_sub_simplices(D, d): """Compute vertices for all sub simplices of dimension d (code taken from Exterior).""" # Number of vertices num_vertices = D + 1 # Special cases: d = 0 and d = D if d == 0: return [[i] for i in range(num_vertices)] elif d == D: return [list(range(num_vertices))] # Compute all permutations of num_vertices - (d + 1) permutations = compute_permutations(num_vertices - d - 1, num_vertices) # Iterate over sub simplices sub_simplices = [] for i in range(len(permutations)): # Pick tuple i among permutations (non-incident vertices) remove = permutations[i] # Remove vertices, keeping d + 1 vertices vertices = [v for v in range(num_vertices) if v not in remove] sub_simplices += [vertices] return sub_simplices
[docs]def uses_integral_moments(fiat_element): "True if element uses integral moments for its degrees of freedom." integrals = set(["IntegralMoment", "FrobeniusIntegralMoment"]) tags = set([L.get_type_tag() for L in fiat_element.dual_basis() if L]) return len(integrals & tags) > 0
[docs]def needs_oriented_jacobian(fiat_element): # Check whether this element needs an oriented jacobian # (only contravariant piolas seem to need it) return "contravariant piola" in fiat_element.mapping()