def compile_form(form, name):
"""Compile a form using FFC and return an OP2 kernel"""
# Check that we get a Form
if not isinstance(form, Form):
form = as_form(form)
return FFCKernel(form, name).kernels
def compile_form(form, name):
"""Compile a form using FFC and return a :class:`pyop2.op2.Kernel`."""
# Check that we get a Form
if not isinstance(form, Form):
form = as_form(form)
return FFCKernel(form, name).kernels
def action(form, coefficient=None):
"""UFL form operator:
Given a bilinear form, return a linear form
with an additional coefficient, representing the
action of the form on the coefficient. This can be
used for matrix-free methods."""
form = as_form(form)
form = expand_derivatives(form)
return compute_form_action(form, coefficient)
def rhs(form):
"""UFL form operator:
Given a combined bilinear and linear form,
extract the right hand side (negated linear form part).
Example:
a = u*v*dx + f*v*dx
L = rhs(a) -> -f*v*dx
"""
form = as_form(form)
form = expand_derivatives(form)
return compute_form_rhs(form)
def lhs(form):
"""UFL form operator:
Given a combined bilinear and linear form,
extract the left hand side (bilinear form part).
Example:
a = u*v*dx + f*v*dx
a = lhs(a) -> u*v*dx
"""
form = as_form(form)
form = expand_derivatives(form)
return compute_form_lhs(form)
def adjoint(form, reordered_arguments=None):
"""UFL form operator:
Given a combined bilinear form, compute the adjoint form by
changing the ordering (count) of the test and trial functions.
By default, new Argument objects will be created with
opposite ordering. However, if the adjoint form is to
be added to other forms later, their arguments must match.
In that case, the user must provide a tuple reordered_arguments=(u2,v2).
"""
form = as_form(form)
form = expand_derivatives(form)
return compute_form_adjoint(form, reordered_arguments)
def functional(form): # TODO: Does this make sense for anything other than testing?
"UFL form operator: Extract the functional part of form."
form = as_form(form)
form = expand_derivatives(form)
return compute_form_functional(form)