def construct_modified_terminal(mt, terminal):
"""Construct a modified terminal given terminal modifiers from an
analysed modified terminal and a terminal."""
expr = terminal
if mt.reference_value:
expr = ReferenceValue(expr)
dim = expr.ufl_domain().topological_dimension()
for n in range(mt.local_derivatives):
# Return zero if expression is trivially constant. This has to
# happen here because ReferenceGrad has no access to the
# topological dimension of a literal zero.
if is_cellwise_constant(expr):
expr = Zero(expr.ufl_shape + (dim, ), expr.ufl_free_indices,
expr.ufl_index_dimensions)
else:
expr = ReferenceGrad(expr)
# No need to apply restrictions to ConstantValue terminals
if not isinstance(expr, ConstantValue):
if mt.restriction == '+':
expr = PositiveRestricted(expr)
elif mt.restriction == '-':
expr = NegativeRestricted(expr)
return expr
def physical_points(self, point_set, entity=None):
"""Converts point_set from reference to physical space"""
expr = SpatialCoordinate(self.mt.terminal.ufl_domain())
point_shape, = point_set.expression.shape
if entity is not None:
e, _ = entity
assert point_shape == e
else:
assert point_shape == expr.ufl_domain().topological_dimension()
if self.mt.restriction == '+':
expr = PositiveRestricted(expr)
elif self.mt.restriction == '-':
expr = NegativeRestricted(expr)
config = {"point_set": point_set}
config.update(self.config)
if entity is not None:
config.update({
name: getattr(self.interface, name)
for name in ["integration_dim", "entity_ids"]
})
context = PointSetContext(**config)
expr = self.preprocess(expr, context)
mapped = map_expr_dag(context.translator, expr)
indices = tuple(gem.Index() for _ in mapped.shape)
return gem.ComponentTensor(gem.Indexed(mapped, indices),
point_set.indices + indices)
def detJ_at(self, point):
expr = JacobianDeterminant(self.mt.terminal.ufl_domain())
if self.mt.restriction == '+':
expr = PositiveRestricted(expr)
elif self.mt.restriction == '-':
expr = NegativeRestricted(expr)
config = {"point_set": PointSingleton(point)}
config.update(self.config)
context = PointSetContext(**config)
expr = self.preprocess(expr, context)
return map_expr_dag(context.translator, expr)
def physical_edge_lengths(self):
expr = ufl.classes.CellEdgeVectors(self.mt.terminal.ufl_domain())
if self.mt.restriction == '+':
expr = PositiveRestricted(expr)
elif self.mt.restriction == '-':
expr = NegativeRestricted(expr)
expr = ufl.as_vector([ufl.sqrt(ufl.dot(expr[i, :], expr[i, :])) for i in range(3)])
expr = preprocess_expression(expr)
config = {"point_set": PointSingleton([1/3, 1/3])}
config.update(self.config)
context = PointSetContext(**config)
return map_expr_dag(context.translator, expr)
def jacobian_at(self, point):
ps = PointSingleton(point)
expr = Jacobian(self.mt.terminal.ufl_domain())
assert ps.expression.shape == (
expr.ufl_domain().topological_dimension(), )
if self.mt.restriction == '+':
expr = PositiveRestricted(expr)
elif self.mt.restriction == '-':
expr = NegativeRestricted(expr)
config = {"point_set": PointSingleton(point)}
config.update(self.config)
context = PointSetContext(**config)
expr = self.preprocess(expr, context)
return map_expr_dag(context.translator, expr)
def construct_modified_terminal(mt, terminal):
"""Construct a modified terminal given terminal modifiers from an
analysed modified terminal and a terminal."""
expr = terminal
if mt.reference_value:
expr = ReferenceValue(expr)
for n in range(mt.local_derivatives):
expr = ReferenceGrad(expr)
if mt.averaged == "cell":
expr = CellAvg(expr)
elif mt.averaged == "facet":
expr = FacetAvg(expr)
# No need to apply restrictions to ConstantValue terminals
if not isinstance(expr, ConstantValue):
if mt.restriction == '+':
expr = PositiveRestricted(expr)
elif mt.restriction == '-':
expr = NegativeRestricted(expr)
return expr