def test_trivial(self):
"""Check the trivial case of matching a point set with itself."""
n = 100
src = self._rng.random_sample((n, 2))
correspondences = [(j, ) * 2 for j in range(n)]
out = bijective_matching(src, src)
self.assertCountEqual(correspondences, out)
def test_maximum_size(self):
"""Check that the matching has maximum size."""
for n, m in itertools.product((100, 105), repeat=2):
with self.subTest(n=n, m=m):
src = self._rng.random_sample((n, 2))
dst = self._rng.random_sample((m, 2))
correspondences = bijective_matching(src, dst)
self.assertEqual(min(n, m), len(list(correspondences)))
def test_permutation(self):
"""Check that a random permutation of a point set can be recovered."""
for n, m in itertools.product((100, 105), repeat=2):
with self.subTest(n=n, m=m):
k = max(n, m)
idx = self._rng.permutation(k)
correspondences = [(j, i) for j, i in zip(idx, range(m))
if j < n]
points = self._rng.random_sample((k, 2))
src = points[:n]
dst = points[idx[:m]]
out = bijective_matching(src, dst)
self.assertCountEqual(correspondences, out)
def test_uniqueness(self):
"""
Check that each `src` or `dst` vertex of the matching is part of
exactly one matching edge.
"""
for n, m in itertools.product((100, 105), repeat=2):
with self.subTest(n=n, m=m):
src = self._rng.random_sample((n, 2))
dst = self._rng.random_sample((m, 2))
correspondences = bijective_matching(src, dst)
for i in (0, 1):
vertices = list(
map(operator.itemgetter(i), correspondences))
self.assertEqual(len(vertices), len(set(vertices)))
def test_sorted(self):
"""
The returned list of correspondences should be sorted by distance in
ascending order.
"""
for n, m in itertools.product((100, 105), repeat=2):
with self.subTest(n=n, m=m):
src = self._rng.random_sample((n, 2))
dst = self._rng.random_sample((m, 2))
correspondences = bijective_matching(src, dst)
distance = [
scipy.spatial.distance.euclidean(src[j], dst[i])
for j, i in correspondences
]
self.assertTrue(
all(itertools.starmap(operator.le, pairwise(distance))))