def test_assert_feasible__contiguity():
with pytest.raises(ValueError) as exc_info:
# nodes 0 and 1 are not connected ...
adj = csr_matrix(np.array([[0, 0], [0, 0]]))
# ... but assigned to the same region --> not feasible
labels = np.array([0, 0])
util.assert_feasible(labels, adj)
assert "not spatially contiguous" in str(exc_info)
def test_assert_feasible__number_of_regions():
with pytest.raises(ValueError) as exc_info:
adj = csr_matrix(np.array([[0, 1],
[1, 0]])) # nodes 0 and 1 are connected ...
labels = np.array([0, 0]) # ... and assigned to the same region
# but this is not feasible under the condition n_regions = 2
n_regions = 2
util.assert_feasible(labels, adj, n_regions=n_regions)
assert "The number of regions is" in str(exc_info)
def test_assert_feasible__contiguity():
with pytest.raises(ValueError) as exc_info:
# nodes 0 and 1 are not connected ...
adj = csr_matrix(np.array([[0, 0],
[0, 0]]))
# ... but assigned to the same region --> not feasible
labels = np.array([0, 0])
util.assert_feasible(labels, adj)
assert "not spatially contiguous" in str(exc_info)
def test_assert_feasible__pass_disconnected():
adj = csr_matrix(np.array([[0, 0],
[0, 0]])) # nodes 0 and 1 are not connected ...
labels = np.array([0, 1]) # ... and assigned to different regions
try:
util.assert_feasible(labels, adj)
util.assert_feasible(labels, adj, n_regions=2)
except ValueError:
pytest.fail()
def test_assert_feasible__number_of_regions():
with pytest.raises(ValueError) as exc_info:
adj = csr_matrix(np.array([[0, 1],
[1, 0]])) # nodes 0 and 1 are connected ...
labels = np.array([0, 0]) # ... and assigned to the same region
# but this is not feasible under the condition n_regions = 2
n_regions = 2
util.assert_feasible(labels, adj, n_regions=n_regions)
assert "The number of regions is" in str(exc_info.value)
def test_assert_feasible__pass_disconnected():
adj = csr_matrix(np.array([[0, 0],
[0, 0]])) # nodes 0 and 1 are not connected ...
labels = np.array([0, 1]) # ... and assigned to different regions
try:
util.assert_feasible(labels, adj)
util.assert_feasible(labels, adj, n_regions=2)
except ValueError:
pytest.fail()
def fit_from_scipy_sparse_matrix(
self,
adj,
attr,
n_regions,
initial_labels=None,
objective_func=ObjectiveFunctionPairwise()):
"""
Perform the AZP algorithm as described in [OR1995]_.
The resulting region labels are assigned to the instance's
:attr:`labels_` attribute.
Parameters
----------
adj : :class:`scipy.sparse.csr_matrix`
Adjacency matrix representing the contiguity relation.
attr : :class:`numpy.ndarray`
Array (number of areas x number of attributes) of areas' attributes
relevant to clustering.
n_regions : `int`
Number of desired regions.
initial_labels : :class:`numpy.ndarray` or None, default: None
One-dimensional array of labels at the beginning of the algorithm.
If None, then a random initial clustering will be generated.
objective_func : :class:`region.objective_function.ObjectiveFunction`, default: ObjectiveFunctionPairwise()
The objective function to use.
"""
if attr.ndim == 1:
attr = attr.reshape(adj.shape[0], -1)
self.allow_move_strategy.attr_all = attr
self.objective_func = objective_func
# step 1
if initial_labels is not None:
assert_feasible(initial_labels, adj, n_regions)
initial_labels_gen = separate_components(adj, initial_labels)
else:
initial_labels_gen = generate_initial_sol(adj, n_regions)
labels = -np.ones(adj.shape[0])
for labels_comp in initial_labels_gen:
comp_idx = np.where(labels_comp != -1)[0]
adj_comp = sub_adj_matrix(adj, comp_idx)
labels_comp = labels_comp[comp_idx]
attr_comp = attr[comp_idx]
self.allow_move_strategy.start_new_component(
labels_comp, attr_comp, self.objective_func, comp_idx)
labels_comp = self._azp_connected_component(
adj_comp, labels_comp, attr_comp)
labels[comp_idx] = labels_comp
self.n_regions = n_regions
self.labels_ = labels
def test_assert_feasible__pass_connected():
adj = csr_matrix(np.array([[0, 1],
[1, 0]])) # nodes 0 and 1 are connected ...
labels = np.array([0, 0]) # ...and (case 1) assigned to the same region
try:
util.assert_feasible(labels, adj)
util.assert_feasible(labels, adj, n_regions=1)
except ValueError:
pytest.fail()
labels = np.array([0, 1]) # ...and (case 2) assigned to different regions
try:
util.assert_feasible(labels, adj)
util.assert_feasible(labels, adj, n_regions=2)
except ValueError:
pytest.fail()
def test_assert_feasible__pass_connected():
adj = csr_matrix(np.array([[0, 1],
[1, 0]])) # nodes 0 and 1 are connected ...
labels = np.array([0, 0]) # ...and (case 1) assigned to the same region
try:
util.assert_feasible(labels, adj)
util.assert_feasible(labels, adj, n_regions=1)
except ValueError:
pytest.fail()
labels = np.array([0, 1]) # ...and (case 2) assigned to different regions
try:
util.assert_feasible(labels, adj)
util.assert_feasible(labels, adj, n_regions=2)
except ValueError:
pytest.fail()