Source code for ufl.constant
# -*- coding: utf-8 -*-
"""This module defines classes representing non-literal values
which are constant with respect to a domain."""
# Copyright (C) 2019 Michal Habera
#
# This file is part of UFL (https://www.fenicsproject.org)
#
# SPDX-License-Identifier: LGPL-3.0-or-later
from ufl.core.ufl_type import ufl_type
from ufl.core.terminal import Terminal
from ufl.domain import as_domain
from ufl.utils.counted import counted_init
[docs]@ufl_type()
class Constant(Terminal):
_ufl_noslots_ = True
_globalcount = 0
def __init__(self, domain, shape=(), count=None):
Terminal.__init__(self)
counted_init(self, count=count, countedclass=Constant)
self._ufl_domain = as_domain(domain)
self._ufl_shape = shape
# Repr string is build in such way, that reconstruction
# with eval() is possible
self._repr = "Constant({}, {}, {})".format(
repr(self._ufl_domain), repr(self._ufl_shape), repr(self._count))
[docs] def count(self):
return self._count
@property
def ufl_shape(self):
return self._ufl_shape
[docs] def ufl_domain(self):
return self._ufl_domain
[docs] def ufl_domains(self):
return (self.ufl_domain(), )
[docs] def is_cellwise_constant(self):
return True
def __str__(self):
count = str(self._count)
if len(count) == 1:
return "c_%s" % count
else:
return "c_{%s}" % count
def __repr__(self):
return self._repr
def __eq__(self, other):
if not isinstance(other, Constant):
return False
if self is other:
return True
return (self._count == other._count and
self._ufl_domain == other._ufl_domain and
self._ufl_shape == self._ufl_shape)
def _ufl_signature_data_(self, renumbering):
"Signature data for constant depends on renumbering"
return "Constant({}, {}, {})".format(
self._ufl_domain._ufl_signature_data_(renumbering), repr(self._ufl_shape),
repr(renumbering[self]))
[docs]def VectorConstant(domain, count=None):
domain = as_domain(domain)
return Constant(domain, shape=(domain.geometric_dimension(), ), count=count)
[docs]def TensorConstant(domain, count=None):
domain = as_domain(domain)
return Constant(domain, shape=(domain.geometric_dimension(), domain.geometric_dimension()), count=count)