def compute_junction_angles(self, weight=None):
"""
Computes the angle at nodes where only three links are connected.
Directions must be assigned before angles can be computed. Also defines
each 3-link node as 'confluence' or 'bifurcation' and appends this
designation to the nodes dictionary.
Parameters
----------
weight : str
[None], 'exp' (exponential), or 'lin' (linear) to determine the
decay of the weights the contributions of pixels as we move away
from the junction node.
"""
if 'certain' not in self.links.keys():
print(
'Junction angles cannot be computed before link directions are set.'
)
else:
self.nodes = lnu.junction_angles(self.links,
self.nodes,
self.imshape,
self.pixlen,
weight=weight)
def test_junction_angles_linear(known_net):
"""Testing junction_angles with linear weighting."""
nodes = known_net.nodes
links = known_net.links
imshape = known_net.imshape
pixlen = known_net.pixlen
# pop junction keys out of nodes before recreating them
_ = nodes.pop('jtype')
_ = nodes.pop('int_ang')
_ = nodes.pop('width_ratio')
nodes = ln_utils.junction_angles(links,
nodes,
imshape,
pixlen,
weight='linear')
assert ('jtype' in nodes.keys()) is True
assert ('int_ang' in nodes.keys()) is True
assert ('width_ratio' in nodes.keys()) is True
def test_junction_angles(test_river):
"""Raise KeyError due to lack of flow directions."""
test_river.compute_network()
with pytest.raises(KeyError):
ln_utils.junction_angles(test_river.links, test_river.nodes,
test_river.Iskel.shape, 5)