def test_permutation_2sided_explicit_4by4_loop_negative():
r"""Test 2sided-perm with explicit method by 4by4 negative arrays with all permutations."""
# define a random matrix
array_a = np.array([[4, 5, -3, 3], [5, 7, 3, -5], [-3, 3, 2, 2],
[3, -5, 2, 5]])
# check with all possible permutation matrices
for comb in itertools.permutations(np.arange(4)):
perm = np.zeros((4, 4))
perm[np.arange(4), comb] = 1
# get array_b by permutation
array_b = np.dot(perm.T, np.dot(array_a, perm))
# check
result = permutation_2sided_explicit(array_a, array_b)
assert_almost_equal(result[2], perm, decimal=6)
assert_almost_equal(result[3], 0, decimal=6)
def test_permutation_2sided_explicit_4by4_translate_scale():
r"""Test 2-sided permutation with explicit method by 4by4 method."""
# define a random matrix
array_a = np.array([[5., 2., 1.], [4., 6., 1.], [1., 6., 3.]])
array_a = np.dot(array_a, array_a.T)
# define array_b by scale-translate array_a and permuting
shift = np.array([[3.14, 3.14, 3.14], [3.14, 3.14, 3.14],
[3.14, 3.14, 3.14]])
perm = np.array([[1., 0., 0.], [0., 0., 1.], [0., 1., 0.]])
array_b = np.dot(perm.T, np.dot((14.7 * array_a + shift), perm))
# check
result = permutation_2sided_explicit(array_a,
array_b,
translate=True,
scale=True)
assert_almost_equal(result[2], perm, decimal=6)
assert_almost_equal(result[3], 0, decimal=6)
def test_permutation_2sided_explicit_4by4_translate_scale_zero_padding():
r"""Test explicit permutation by 4by4 arrays with translation, scaling and zero padding."""
# define a random matrix
array_a = np.array([[4, 5, -3, 3], [5, 7, 3, -5], [-3, 3, 2, 2],
[3, -5, 2, 5]])
# check with all possible permutation matrices
perm = np.array([[0, 0, 1, 0], [1, 0, 0, 0], [0, 1, 0, 0], [0, 0, 0, 1]])
# Compute the translated, scaled matrix padded with zeros
array_b = np.dot(perm.T, np.dot(20 * array_a + 9, perm))
# pad the matrices with zeros
array_b = np.concatenate((array_b, np.zeros((4, 2))), axis=1)
array_b = np.concatenate((array_b, np.zeros((6, 6))), axis=0)
# check
result = permutation_2sided_explicit(array_a,
array_b,
translate=True,
scale=True)
assert_almost_equal(result[2], perm, decimal=6)
assert_almost_equal(result[3], 0, decimal=6)