def testPadWithOneReflectionIsCorrect(self):
"""Tests that pad_reflecting(p) matches np.pad(p) when p is small."""
for _ in range(4):
n = int(np.ceil(np.random.uniform() * 8)) + 1
x = np.random.uniform(size=(n, n, n))
padding_below = int(np.round(np.random.uniform() * (n - 1)))
padding_above = int(np.round(np.random.uniform() * (n - 1)))
axis = int(np.floor(np.random.uniform() * 3.))
if axis == 0:
reference = np.pad(
x, [[padding_below, padding_above], [0, 0], [0, 0]],
'reflect')
elif axis == 1:
reference = np.pad(
x, [[0, 0], [padding_below, padding_above], [0, 0]],
'reflect')
elif axis == 2:
reference = np.pad(
x, [[0, 0], [0, 0], [padding_below, padding_above]],
'reflect')
result = wavelet.pad_reflecting(x, padding_below, padding_above,
axis)
np.testing.assert_equal(result.shape, reference.shape)
np.testing.assert_equal(result, reference)
def testPadWithManyReflectionsIsCorrect(self):
"""Tests that pad_reflecting(k * p) matches np.pad(p) applied k times."""
for _ in range(4):
n = int(np.random.uniform() * 8.) + 1
p = n - 1
x = np.random.uniform(size=(n))
reference1 = np.pad(x, [[p, p]], 'reflect')
reference2 = np.pad(reference1, [[p, p]], 'reflect')
reference3 = np.pad(reference2, [[p, p]], 'reflect')
result1 = wavelet.pad_reflecting(x, p, p, 0)
result2 = wavelet.pad_reflecting(x, 2 * p, 2 * p, 0)
result3 = wavelet.pad_reflecting(x, 3 * p, 3 * p, 0)
np.testing.assert_equal(result1.shape, reference1.shape)
np.testing.assert_equal(result1, reference1)
np.testing.assert_equal(result2.shape, reference2.shape)
np.testing.assert_equal(result2, reference2)
np.testing.assert_equal(result3.shape, reference3.shape)
np.testing.assert_equal(result3, reference3)
def testPadWithManyReflectionsGolden2IsCorrect(self):
"""Tests pad_reflecting() against a golden example."""
n = 11
p0 = 15
p1 = 7
x = np.arange(n)
reference = np.concatenate((np.arange(5, n), np.arange(n - 2, 0, -1),
np.arange(n), np.arange(n - 2, 2, -1)))
result = wavelet.pad_reflecting(x, p0, p1, 0)
np.testing.assert_equal(result.shape, reference.shape)
np.testing.assert_equal(result, reference)
