def assemble(f, tensor=None, bcs=None):
"""Evaluate f.
:arg f: a :class:`ufl.Form` or :class:`ufl.expr.Expr`.
:arg tensor: an existing tensor object to place the result in
(optional).
:arg bcs: a list of boundary conditions to apply (optional).
If f is a :class:`ufl.Form` then this evaluates the corresponding
integral(s) and returns a :class:`float` for 0-forms, a
:class:`.Function` for 1-forms and a :class:`.Matrix` for 2-forms.
If f is an expression other than a form, it will be evaluated
pointwise on the :class:`.Function`\s in the expression. This will
only succeed if all the Functions are on the same
:class:`.FunctionSpace`
If ``tensor`` is supplied, the assembled result will be placed
there, otherwise a new object of the appropriate type will be
returned.
"""
if isinstance(f, ufl.form.Form):
return _assemble(f, tensor=tensor, bcs=_extract_bcs(bcs))
elif isinstance(f, ufl.expr.Expr):
return assemble_expressions.assemble_expression(f)
else:
raise TypeError("Unable to assemble: %r" % f)
def assemble(f, tensor=None, bcs=None, form_compiler_parameters=None,
inverse=False, nest=None):
"""Evaluate f.
:arg f: a :class:`ufl.Form` or :class:`ufl.core.expr.Expr`.
:arg tensor: an existing tensor object to place the result in
(optional).
:arg bcs: a list of boundary conditions to apply (optional).
:arg form_compiler_parameters: (optional) dict of parameters to pass to
the form compiler. Ignored if not assembling a
:class:`ufl.Form`. Any parameters provided here will be
overridden by parameters set on the :class;`ufl.Measure` in the
form. For example, if a :data:`quadrature_degree` of 4 is
specified in this argument, but a degree of 3 is requested in
the measure, the latter will be used.
:arg inverse: (optional) if f is a 2-form, then assemble the inverse
of the local matrices.
:arg nest: (optional) flag indicating if a 2-form (matrix) on a
mixed space should be assembled as a block matrix (if
:data:`nest` is :data:`True`) or not. The default value is
taken from the parameters dict :data:`parameters["matnest"]`.
If f is a :class:`ufl.Form` then this evaluates the corresponding
integral(s) and returns a :class:`float` for 0-forms, a
:class:`.Function` for 1-forms and a :class:`.Matrix` for 2-forms.
If f is an expression other than a form, it will be evaluated
pointwise on the :class:`.Function`\s in the expression. This will
only succeed if all the Functions are on the same
:class:`.FunctionSpace`
If ``tensor`` is supplied, the assembled result will be placed
there, otherwise a new object of the appropriate type will be
returned.
If ``bcs`` is supplied and ``f`` is a 2-form, the rows and columns
of the resulting :class:`.Matrix` corresponding to boundary nodes
will be set to 0 and the diagonal entries to 1. If ``f`` is a
1-form, the vector entries at boundary nodes are set to the
boundary condition values.
"""
if isinstance(f, ufl.form.Form):
return _assemble(f, tensor=tensor, bcs=solving._extract_bcs(bcs),
form_compiler_parameters=form_compiler_parameters,
inverse=inverse, nest=nest)
elif isinstance(f, ufl.core.expr.Expr):
return assemble_expressions.assemble_expression(f)
else:
raise TypeError("Unable to assemble: %r" % f)