From 8b67d07294745d5aae37b96a0ca1fa53563d33a1 Mon Sep 17 00:00:00 2001
From: manuelpett <manuel.petit@inria.fr>
Date: Wed, 23 Oct 2024 15:19:14 +0200
Subject: [PATCH] Make the use of VariableDirichlet more flexible. Add tests
for ConstantDirichlet and VariableDirichlet.
Extended the test suite to include tests for newly added `ConstantDirichlet` and `VariableDirichlet` classes in `test_dirichlet.py`. Also refactored the `VariableDirichlet` class to utilize a new utility function for expression creation and pre-formatting.
---
src/bvpy/boundary_conditions/dirichlet.py | 31 ++++++----
test/test_dirichlet.py | 75 ++++++++++++++++++++---
2 files changed, 85 insertions(+), 21 deletions(-)
diff --git a/src/bvpy/boundary_conditions/dirichlet.py b/src/bvpy/boundary_conditions/dirichlet.py
index 7255301..b1d018d 100644
--- a/src/bvpy/boundary_conditions/dirichlet.py
+++ b/src/bvpy/boundary_conditions/dirichlet.py
@@ -23,16 +23,10 @@ import fenics as fe
from bvpy import logger
import numpy as np
-from sympy import Symbol
-from sympy.parsing.sympy_parser import parse_expr
from .boundary import Boundary
from bvpy.domains.geometry import boundary_normal
-
-_XYZ = {'x': Symbol('x[0]'),
- 'y': Symbol('x[1]'),
- 'z': Symbol('x[2]')}
-
+from bvpy.utils.pre_processing import create_expression, _stringify_expression_from_string
class ConstantDirichlet(object):
"""Defines a constant Dirichlet condition on a domain.
@@ -121,10 +115,21 @@ class ConstantDirichlet(object):
class VariableDirichlet(object):
"""Defines a variable Dirichlet condition on a domain.
+ The `val` argument allows to pass a string expression that can be :
+
+ val = "sin(x) + cos(y)" # scalar
+ val = "(x, y * pow(x,2))" # vector
+
+ Tensor expressions of rank 2 (matrices) may also be created:
+
+ val = "((exp(x), sin(y)),
+ (sin(x), tan(y))"
+
+ See <cmath> for the available functions. https://cplusplus.com/reference/cmath/
"""
def __init__(self, val, boundary="all",
- method='topological', subspace=None, degree=None):
+ method='topological', subspace=None, degree=None, **kwargs):
"""Generator of the VariableDirichlet class.
Parameters
@@ -161,6 +166,7 @@ class VariableDirichlet(object):
self._method = method
self._subspace = subspace
self._degree = degree
+ self._extra_kwargs = kwargs
def apply(self, functionSpace):
"""Applies the specified condition on the actual function space.
@@ -177,12 +183,13 @@ class VariableDirichlet(object):
The boundary condition in a fenics-readable format.
"""
- parse = parse_expr(self._val, local_dict=_XYZ, evaluate=False)
+ # Pre-format the input value (if vector or tensor)
+ val = _stringify_expression_from_string(self._val)
+
if self._degree is None:
- expr = fe.Expression(str(parse),
- element=functionSpace.ufl_element())
+ expr = create_expression(val, functionspace=functionSpace, **self._extra_kwargs)
else:
- expr = fe.Expression(str(parse), degree=self._degree)
+ expr = create_expression(val, degree=self._degree, **self._extra_kwargs)
if self._subspace is None:
dir = fe.DirichletBC(functionSpace, expr,
diff --git a/test/test_dirichlet.py b/test/test_dirichlet.py
index d5e2ae9..8877412 100644
--- a/test/test_dirichlet.py
+++ b/test/test_dirichlet.py
@@ -1,6 +1,6 @@
import unittest
-from bvpy.boundary_conditions.dirichlet import NormalDirichlet, ZeroDirichlet
-from bvpy.boundary_conditions import Boundary
+from bvpy.boundary_conditions.dirichlet import NormalDirichlet, ZeroDirichlet, ConstantDirichlet, VariableDirichlet
+from bvpy.boundary_conditions import Boundary, dirichlet
import fenics as fe
from numpy.testing import assert_array_equal
@@ -10,23 +10,80 @@ class TestDirichlet(unittest.TestCase):
def setUp(self):
"""Initiates the test.
"""
+ self.mesh = fe.UnitSquareMesh(2, 2)
+ self.V = fe.VectorFunctionSpace(self.mesh, 'P', 1)
+ self.scalar_V = fe.FunctionSpace(self.mesh, 'P', 1)
def tearDown(self):
"""Concludes and closes the test.
"""
def test_normal(self):
- mesh = fe.UnitSquareMesh(2, 2)
- V = fe.VectorFunctionSpace(mesh, 'P', 1)
- diri = NormalDirichlet(boundary='all')
diri = NormalDirichlet(boundary=Boundary('all'))
- self.assertEqual("<NormalDirichlet object, location: all, value: 1>",
- diri.__repr__())
-
- d = diri.apply(V)
+ self.assertEqual("<NormalDirichlet object, location: all, value: 1>", diri.__repr__())
+ d = diri.apply(self.V)
self.assertEqual(d.get_boundary_values()[5], 1)
def test_zero(self):
b = Boundary("all")
diri = ZeroDirichlet(b, shape=3)
assert_array_equal(diri._val, [0, 0, 0])
+
+ def test_constant(self):
+ # - vector
+ val = (1, 2)
+ boundary = Boundary('all')
+ diri = ConstantDirichlet(val, boundary=boundary, method='topological')
+ self.assertEqual(diri._val, val)
+ self.assertEqual(diri._boundary, boundary)
+ self.assertEqual(diri._method, 'topological')
+ d = diri.apply(self.V)
+ for bc_val in d.get_boundary_values().values():
+ self.assertIn(bc_val, val)
+
+ # - scalar
+ val = 2
+ boundary = Boundary('all')
+ diri = ConstantDirichlet(val, boundary=boundary)
+ self.assertEqual(diri._val, val)
+ self.assertEqual(diri._boundary, boundary)
+ d = diri.apply(self.scalar_V)
+ bc_vals = d.get_boundary_values().values()
+ assert_array_equal(list(bc_vals), [val] * len(bc_vals))
+
+ # - subspace
+ diri = ConstantDirichlet(val, boundary=boundary, subspace=0)
+ self.assertEqual(diri._val, val)
+ self.assertEqual(diri._boundary, boundary)
+ d = diri.apply(self.V)
+ bc_vals = d.get_boundary_values().values()
+ assert_array_equal(list(bc_vals), [val] * len(bc_vals))
+
+ def test_variable(self):
+ # - vector
+ val = '(x, y)'
+ boundary = Boundary('all')
+ diri = VariableDirichlet(val, boundary=boundary, degree=1)
+ self.assertEqual(diri._val, val)
+ self.assertEqual(diri._boundary, boundary)
+ d = diri.apply(self.V)
+ bc_vals = d.get_boundary_values().values()
+ self.assertTrue(all(val >= 0 and val <= 2 for val in bc_vals))
+
+ # - scalar
+ val = "x"
+ boundary = Boundary('all')
+ diri = VariableDirichlet(val, boundary=boundary, degree=1)
+ self.assertEqual(diri._val, val)
+ self.assertEqual(diri._boundary, boundary)
+ d = diri.apply(self.scalar_V)
+ bc_vals = d.get_boundary_values().values()
+ self.assertTrue(all(val >= 0 and val <= 1 for val in bc_vals))
+
+ # - subspace
+ diri = dirichlet(val, boundary=boundary, subspace=0, degree=1)
+ self.assertEqual(diri._val, val)
+ self.assertEqual(diri._boundary, boundary)
+ d = diri.apply(self.V)
+ bc_vals = d.get_boundary_values().values()
+ self.assertTrue(all(val >= 0 and val <= 1 for val in bc_vals))
--
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