def test_fft3d_direction_error(fake_data_deterministic):
"""Test _fft3d error in direction kwarg."""
data, is_random = fake_data_deterministic
# test giving a bogus direction
with pytest.raises(ValueError) as cm:
zreion._fft3d(data, data.shape, direction="blah")
assert str(
cm.value).startswith('"direction" must be "f" or "b", got "blah"')
return
def test_fft3d_rank_errors(fake_data_deterministic):
"""Test _fft3d errors with data rank."""
data, is_random = fake_data_deterministic
with pytest.raises(ValueError) as cm:
zreion._fft3d(data, (0, ), direction="f")
assert str(cm.value).startswith("data_shape must have 3 dimensions")
data_1d = data[0, 0, :]
with pytest.raises(ValueError) as cm:
zreion._fft3d(data_1d, data.shape, direction="f")
assert str(
cm.value).startswith("input array must be a 3-dimensional array")
return
def test_fft3d_backward_double(fake_data):
"""Test backward _fft3d function with double-precision."""
data, is_random = fake_data
data = np.asarray(data, dtype=np.float64)
fake_data_ft = np.asarray(np.fft.rfftn(data), dtype=np.complex128)
# run zreion fft
input_shape = data.shape
zreion_fft = zreion._fft3d(fake_data_ft, input_shape, direction="b")
assert np.allclose(zreion_fft, data)
assert zreion_fft.dtype.type is np.float64
return
def test_fft3d_backward(fake_data):
"""Test backward _fft3d function."""
data, is_random = fake_data
# use numpy as reference FFT
fake_data_ft = np.asarray(np.fft.rfftn(data), dtype=np.complex64)
# run zreion fft
input_shape = data.shape
zreion_fft = zreion._fft3d(fake_data_ft, input_shape, direction="b")
assert np.allclose(zreion_fft, data, atol=1e-6)
assert zreion_fft.dtype.type is np.float32
return
def test_fft3d_forward_double_precision(fake_data):
"""Test _fft3d function with double-precision."""
data, is_random = fake_data
data = np.asarray(data, dtype=np.float64)
# use numpy as reference FFT
numpy_fft = np.fft.rfftn(data)
# run zreion fft
input_shape = data.shape
zreion_fft = zreion._fft3d(data, input_shape, direction="f")
assert np.allclose(numpy_fft, zreion_fft)
assert zreion_fft.dtype.type is np.complex128
return
def test_fft3d_forward(fake_data):
"""Test _fft3d function."""
data, is_random = fake_data
# use numpy as reference FFT
numpy_fft = np.fft.rfftn(data)
# run zreion fft
input_shape = data.shape
zreion_fft = zreion._fft3d(data, input_shape, direction="f")
# need relatively high tolerance because numpy fft is internally done at
# double precision, seemingly without a way to change it
assert np.allclose(numpy_fft, zreion_fft, atol=1e-4)
assert zreion_fft.dtype.type is np.complex64
return
def test_fft3d_datatype_errors(fake_data_deterministic):
"""Test _fft3d errors with bad datatypes."""
data, is_random = fake_data_deterministic
# test using incorrect direction for real data
with pytest.raises(ValueError) as cm:
zreion._fft3d(data, data.shape, direction="b")
assert str(cm.value).startswith("a backward transform requires")
# test using incorrect direction for complex data
complex_data = np.asarray(data, dtype=np.complex64)
with pytest.raises(ValueError) as cm:
zreion._fft3d(complex_data, data.shape, direction="f")
assert str(cm.value).startswith("a forward transform requires")
# test using integer datatype
int_data = np.asarray(data, dtype=np.int32)
with pytest.raises(ValueError) as cm:
zreion._fft3d(int_data, data.shape, direction="f")
assert str(cm.value).startswith("a forward transform requires")
return