def test_data_managment():
"""test how data is set"""
grid = UnitGrid([2, 2])
for cls in (ScalarField, VectorField, Tensor2Field):
s1 = cls(grid, data=1)
np.testing.assert_allclose(s1.data, 1)
s2 = cls(grid)
np.testing.assert_allclose(s2.data, 0)
c = FieldCollection([s1, s2])
s1.data = 0
np.testing.assert_allclose(c.data, 0)
c.data = 2
np.testing.assert_allclose(s1.data, 2)
np.testing.assert_allclose(s2.data, 2)
c.data += 1
np.testing.assert_allclose(s1.data, 3)
np.testing.assert_allclose(s2.data, 3)
c[0].data += 2 # reference to s1
c[1].data *= 2 # reference to s2
np.testing.assert_allclose(s1.data, 5)
np.testing.assert_allclose(s2.data, 6)
c[0] = s2
np.testing.assert_allclose(c.data, 6)
# nested collections
with pytest.raises(RuntimeError):
FieldCollection([c])
def test_kymograph_collection(tmp_path):
"""test making kymographs for field collections"""
# create some storage
field = FieldCollection([
ScalarField(UnitGrid(8), label="a"),
ScalarField(UnitGrid(8), label="b")
])
with get_memory_storage(field) as storage:
for i in range(8):
field.data = i
storage.append(field, i)
# create single kymograph
path = tmp_path / "test1.png"
plotting.plot_kymograph(storage,
field_index=1,
colorbar=True,
transpose=True,
filename=path)
assert path.stat().st_size > 0
# create multiple kymographs
path = tmp_path / "test2.png"
plotting.plot_kymographs(storage, filename=path)
assert path.stat().st_size > 0
def test_shapes_nfields(num, example_grid):
"""test single component field"""
fields = [ScalarField.random_uniform(example_grid) for _ in range(num)]
field = FieldCollection(fields)
data_shape = (num, ) + example_grid.shape
np.testing.assert_equal(field.data.shape, data_shape)
for pf_single in field:
np.testing.assert_equal(pf_single.data.shape, example_grid.shape)
field_c = field.copy()
np.testing.assert_allclose(field.data, field_c.data)
assert field.grid == field_c.grid
def test_pde_critical_input():
"""test some wrong input and edge cases"""
# test whether reserved symbols can be used as variables
grid = grids.UnitGrid([4])
eq = PDE({"E": 1})
res = eq.solve(ScalarField(grid), t_range=2)
np.testing.assert_allclose(res.data, 2)
with pytest.raises(ValueError):
PDE({"t": 1})
eq = PDE({"u": 1})
assert eq.expressions == {"u": "1.0"}
with pytest.raises(ValueError):
eq.evolution_rate(FieldCollection.scalar_random_uniform(2, grid))
eq = PDE({"u": 1, "v": 2})
assert eq.expressions == {"u": "1.0", "v": "2.0"}
with pytest.raises(ValueError):
eq.evolution_rate(ScalarField.random_uniform(grid))
eq = PDE({"u": "a"})
with pytest.raises(RuntimeError):
eq.evolution_rate(ScalarField.random_uniform(grid))
eq = PDE({"x": "x"})
with pytest.raises(ValueError):
eq.evolution_rate(ScalarField(grid))
def test_scalar_arithmetics():
"""test simple arithmetics involving scalar fields"""
grid = UnitGrid([3, 4])
s = ScalarField(grid, data=2)
v = VectorField.random_uniform(grid)
for f in [v, FieldCollection([v])]:
f.data = s
assert f.data.shape == (2, 3, 4)
np.testing.assert_allclose(f.data, 2)
f += s
np.testing.assert_allclose(f.data, 4)
np.testing.assert_allclose((f + s).data, 6)
np.testing.assert_allclose((s + f).data, 6)
f -= s
np.testing.assert_allclose((f - s).data, 0)
np.testing.assert_allclose((s - f).data, 0)
f *= s
np.testing.assert_allclose(f.data, 4)
np.testing.assert_allclose((f * s).data, 8)
np.testing.assert_allclose((s * f).data, 8)
f /= s
np.testing.assert_allclose((f / s).data, 1)
with pytest.raises(TypeError):
s / f
with pytest.raises(TypeError):
s /= f
with pytest.raises(TypeError):
s *= f
def test_pde_wrong_input():
"""test some wrong input"""
with pytest.raises(ValueError):
PDE({"t": 1})
with pytest.raises(ValueError):
PDE({"E": 1})
with pytest.raises(ValueError):
PDE({"E": 1, "t": 0})
grid = grids.UnitGrid([4])
eq = PDE({"u": 1})
assert eq.expressions == {"u": "1.0"}
with pytest.raises(ValueError):
eq.evolution_rate(FieldCollection.scalar_random_uniform(2, grid))
eq = PDE({"u": 1, "v": 2})
assert eq.expressions == {"u": "1.0", "v": "2.0"}
with pytest.raises(ValueError):
eq.evolution_rate(ScalarField.random_uniform(grid))
eq = PDE({"u": "a"})
with pytest.raises(RuntimeError):
eq.evolution_rate(ScalarField.random_uniform(grid))
eq = PDE({"x": "x"})
with pytest.raises(ValueError):
eq.evolution_rate(ScalarField(grid))
def test_field_type_guessing():
""" test the ability to guess the field type """
for cls in [ScalarField, VectorField, Tensor2Field]:
grid = UnitGrid([3])
field = cls.random_normal(grid)
s = MemoryStorage()
s.start_writing(field)
s.append(field, 0)
s.append(field, 1)
# delete information
s._field = None
s.info = {}
assert not s.has_collection
assert len(s) == 2
assert s[0] == field
field = FieldCollection([ScalarField(grid), VectorField(grid)])
s = MemoryStorage()
s.start_writing(field)
s.append(field, 0)
assert s.has_collection
# delete information
s._field = None
s.info = {}
with pytest.raises(RuntimeError):
s[0]
def test_storing_collection(tmp_path):
""" test methods specific to FieldCollections in memory storage """
grid = UnitGrid([2, 2])
f1 = ScalarField.random_uniform(grid, 0.1, 0.4, label="a")
f2 = VectorField.random_uniform(grid, 0.1, 0.4, label="b")
f3 = Tensor2Field.random_uniform(grid, 0.1, 0.4, label="c")
fc = FieldCollection([f1, f2, f3])
storage_classes = {"MemoryStorage": MemoryStorage}
if module_available("h5py"):
file_path = tmp_path / "test_storage_write.hdf5"
storage_classes["FileStorage"] = functools.partial(
FileStorage, file_path)
for storage_cls in storage_classes.values():
# store some data
storage = storage_cls()
storage.start_writing(fc)
storage.append(fc, 0)
storage.append(fc, 1)
storage.end_writing()
assert storage.has_collection
assert storage.extract_field(0)[0] == f1
assert storage.extract_field(1)[0] == f2
assert storage.extract_field(2)[0] == f3
assert storage.extract_field(0)[0].label == "a"
assert storage.extract_field(0,
label="new label")[0].label == "new label"
assert storage.extract_field(0)[0].label == "a" # do not alter label
assert storage.extract_field("a")[0] == f1
assert storage.extract_field("b")[0] == f2
assert storage.extract_field("c")[0] == f3
with pytest.raises(ValueError):
storage.extract_field("nonsense")
def test_interpolation_to_grid_fields():
""" test whether data is interpolated correctly for different fields """
grid = CartesianGrid([[0, 2 * np.pi]] * 2, 6)
grid2 = CartesianGrid([[0, 2 * np.pi]] * 2, 8)
vf = VectorField.from_expression(grid, ["sin(y)", "cos(x)"])
sf = vf[0] # test extraction of fields
fc = FieldCollection([sf, vf])
for f in [sf, vf, fc]:
f2 = f.interpolate_to_grid(grid2, method="numba")
f3 = f2.interpolate_to_grid(grid, method="numba")
np.testing.assert_allclose(f.data, f3.data, atol=0.2, rtol=0.2)
def test_collection_plot(tmp_path):
"""test Simple simulation"""
# create some data
field = FieldCollection([
ScalarField(UnitGrid([8, 8]), label="first"),
ScalarField(UnitGrid([8, 8]))
])
with get_memory_storage(field) as storage:
storage.append(field)
path = tmp_path / "test_collection_plot.png"
plotting.plot_magnitudes(storage, filename=path)
assert path.stat().st_size > 0
def test_pde_2scalar():
"""test PDE with two scalar fields"""
eq = PDE({"u": "laplace(u) - u", "v": "- u * v"})
assert not eq.explicit_time_dependence
assert not eq.complex_valued
grid = grids.UnitGrid([8])
field = FieldCollection.scalar_random_uniform(2, grid)
res_a = eq.solve(field, t_range=1, dt=0.01, backend="numpy", tracker=None)
res_b = eq.solve(field, t_range=1, dt=0.01, backend="numba", tracker=None)
res_a.assert_field_compatible(res_b)
np.testing.assert_allclose(res_a.data, res_b.data)
def test_simple_plotting(example_grid):
"""test simple plotting of various fields on various grids"""
vf = VectorField.random_uniform(example_grid)
tf = Tensor2Field.random_uniform(example_grid)
sf = tf[0, 0] # test extraction of fields
fc = FieldCollection([sf, vf])
for f in [sf, vf, tf, fc]:
f.plot(action="close")
f.plot(kind="line", action="close")
if example_grid.dim >= 2:
f.plot(kind="image", action="close")
if isinstance(f, VectorField) and example_grid.dim == 2:
f.plot(kind="quiver", action="close")
f.plot(kind="streamplot", action="close")
def test_pde_vector_scalar():
"""test PDE with a vector and a scalar field"""
eq = PDE({"u": "vector_laplace(u) - u + gradient(v)", "v": "- divergence(u)"})
assert not eq.explicit_time_dependence
assert not eq.complex_valued
grid = grids.UnitGrid([8, 8])
field = FieldCollection(
[VectorField.random_uniform(grid), ScalarField.random_uniform(grid)]
)
res_a = eq.solve(field, t_range=1, dt=0.01, backend="numpy", tracker=None)
res_b = eq.solve(field, t_range=1, dt=0.01, backend="numba", tracker=None)
res_a.assert_field_compatible(res_b)
np.testing.assert_allclose(res_a.data, res_b.data)
def test_hdf_input_output(tmp_path):
"""test writing and reading files"""
grid = UnitGrid([4, 4])
s = ScalarField.random_uniform(grid, label="scalar")
v = VectorField.random_uniform(grid, label="vector")
t = Tensor2Field.random_uniform(grid, label="tensor")
col = FieldCollection([s, v, t], label="collection")
path = tmp_path / "test_hdf_input_output.hdf5"
for f in [s, v, t, col]:
f.to_file(path)
f2 = FieldBase.from_file(path)
assert f == f2
assert f.label == f2.label
assert isinstance(str(f), str)
assert isinstance(repr(f), str)
def test_pde_noise(backend):
"""test noise operator on PDE class"""
grid = grids.UnitGrid([64, 64])
state = FieldCollection([ScalarField(grid), ScalarField(grid)])
eq = PDE({"a": 0, "b": 0}, noise=0.5)
res = eq.solve(state, t_range=1, backend=backend, dt=1, tracker=None)
assert res.data.std() == pytest.approx(0.5, rel=0.1)
eq = PDE({"a": 0, "b": 0}, noise=[0.01, 2.0])
res = eq.solve(state, t_range=1, backend=backend, dt=1)
assert res.data[0].std() == pytest.approx(0.01, rel=0.1)
assert res.data[1].std() == pytest.approx(2.0, rel=0.1)
with pytest.raises(ValueError):
eq = PDE({"a": 0}, noise=[0.01, 2.0])
eq.solve(ScalarField(grid), t_range=1, backend=backend, dt=1, tracker=None)
def test_interpolation_to_cartesian(grid):
"""test whether data is interpolated correctly to Cartesian grid"""
dim = grid.dim
vf = VectorField(grid, 2)
sf = vf[0] # test extraction of fields
fc = FieldCollection([sf, vf])
# subset
grid_cart = UnitGrid([4] * dim)
for f in [sf, fc]:
res = f.interpolate_to_grid(grid_cart)
np.testing.assert_allclose(res.data, 2)
# superset
grid_cart = UnitGrid([8] * dim)
for f in [sf, fc]:
res = f.interpolate_to_grid(grid_cart, fill=0)
assert res.data.min() == 0
assert res.data.max() == pytest.approx(2)
def test_interpolation_to_grid_fields(ndim):
"""test whether data is interpolated correctly for different fields"""
grid = CartesianGrid([[0, 2 * np.pi]] * ndim, 6)
grid2 = CartesianGrid([[0, 2 * np.pi]] * ndim, 8)
if ndim == 1:
vf = VectorField.from_expression(grid, ["cos(x)"])
elif ndim == 2:
vf = VectorField.from_expression(grid, ["sin(y)", "cos(x)"])
sf = vf[0] # test extraction of fields
fc = FieldCollection([sf, vf])
for f in [sf, vf, fc]:
# test self-interpolation
f0 = f.interpolate_to_grid(grid, backend="numba")
np.testing.assert_allclose(f.data, f0.data, atol=1e-15)
# test interpolation to finer grid and back
f2 = f.interpolate_to_grid(grid2, backend="numba")
f3 = f2.interpolate_to_grid(grid, backend="numba")
np.testing.assert_allclose(f.data, f3.data, atol=0.2, rtol=0.2)
