def via_via(via):
path1 = dijkstra_path(adjacency, weight, start, via)
path2 = dijkstra_path(adjacency, weight, via, end)
path = path1 + path2[1:]
edges = []
for i in range(len(path) - 1):
u = path[i]
v = path[i + 1]
if v not in network.edge[u]:
u, v = v, u
edges.append([u, v])
vertexcolor = {}
vertexcolor[start] = '#00ff00'
vertexcolor[end] = '#00ff00'
vertexcolor[via] = '#0000ff'
plotter.clear_vertices()
plotter.clear_edges()
plotter.draw_vertices(text={key: key for key in (start, via, end)},
textcolor={key: '#ffffff' for key in path[1:-1]},
facecolor=vertexcolor,
radius=0.15,
picker=10)
plotter.draw_edges(color={(u, v): '#ff0000' for u, v in edges},
width={(u, v): 4.0 for u, v in edges},
text={(u, v): '{:.1f}'.format(weight[(u, v)]) for u, v in network.edges()},
fontsize=4.0)
def via_via(via):
# compute the shortest path from start to via
# and from via to end
# combine the paths
path1 = dijkstra_path(adjacency, weight, start, via)
path2 = dijkstra_path(adjacency, weight, via, end)
path = path1 + path2[1:]
edges = []
for i in range(len(path) - 1):
u = path[i]
v = path[i + 1]
if v not in network.edge[u]:
u, v = v, u
edges.append([u, v])
# update the plot
vertexcolor = {}
vertexcolor[start] = '#00ff00'
vertexcolor[end] = '#00ff00'
vertexcolor[via] = '#FF00F6'
plotter.clear_vertices()
plotter.clear_edges()
plotter.draw_vertices(text={key: key
for key in (start, via, end)},
textcolor={key: '#ffffff'
for key in path[1:-1]},
facecolor=vertexcolor,
radius=3,
picker=20)
plotter.draw_edges(color={(u, v): '#ff0000'
for u, v in edges},
width={(u, v): 4.0
for u, v in edges})
def network_order(start, structure, network):
""" Extract node and element orders from a Network for a given start-point.
Parameters
----------
start : list
Start point co-ordinates.
structure : obj
Structure object.
network : obj
Network object.
Returns
-------
list
Ordered nodes.
list
Ordered elements.
list
Cumulative lengths at element mid-points.
float
Total length.
"""
gkey_key = network.gkey_key()
start = gkey_key[geometric_key(start, '{0}f'.format(structure.tol))]
leaves = network.leaves()
leaves.remove(start)
end = leaves[0]
adjacency = {i: network.vertex_neighbors(i) for i in network.vertices()}
weight = {(u, v): 1 for u, v in network.edges()}
weight.update({(v, u): weight[(u, v)] for u, v in network.edges()})
path = dijkstra_path(adjacency, weight, start, end)
nodes = [
structure.check_node_exists(network.vertex_coordinates(i))
for i in path
]
elements, arclengths, length = [], [], 0
for i in range(len(nodes) - 1):
sp = nodes[i]
ep = nodes[i + 1]
elements.append(structure.check_element_exists([sp, ep]))
xyz_sp = structure.node_xyz(sp)
xyz_ep = structure.node_xyz(ep)
dL = distance_point_point(xyz_sp, xyz_ep)
arclengths.append(length + dL / 2.)
length += dL
return nodes, elements, arclengths, length
start = end = 0
while start == end:
start = choice(leaves)
end = choice(leaves)
# construc an adjacency dict
# add weight to the edges corresponding to their length
# compute the shortest path
adjacency = {key: network.vertex_neighbors(key) for key in network.vertices()}
weight = {(u, v): network.edge_length(u, v) for u, v in network.edges()}
weight.update({(v, u): weight[(u, v)] for u, v in network.edges()})
path = dijkstra_path(adjacency, weight, start, end)
# visualize the result
plotter = NetworkPlotter(network, figsize=(10, 8), fontsize=6)
edges = []
for u, v in pairwise(path):
if v not in network.edge[u]:
u, v = v, u
edges.append([u, v])
plotter.draw_vertices(
text={key: key
for key in (start, end)},
facecolor={key: '#ff0000'
artist = NetworkArtist(network, layer='new_lines')
artist.draw_vertices(color=(255, 0, 0))
artist.redraw()
# select vertices
vertices = network_select_vertices(network, "select a network vertices")
print(vertices)
adjacency = {
key: network.vertex_neighbors(key)
for key in network.vertices()
}
weight = {(u, v): network.edge_length(u, v) for u, v in network.edges()}
weight.update({(v, u): weight[(u, v)] for u, v in network.edges()})
path = dijkstra_path(adjacency, weight, vertices[0], vertices[1])
print(path)
edges = []
for u, v in pairwise(path):
if v not in network.edge[u]:
u, v = v, u
edges.append((u, v))
artist.draw_edges(keys=edges, color=(255, 0, 0))
artist.clear_vertices()
artist.redraw()
# add the same weight in both directions
weight.update({(v, u): weight[(u, v)] for u, v in network.edges()})
# set high weights for some specific edges
weight[(18, 1)] = 100
weight[(1, 18)] = 100
weight[(0, 18)] = 100
weight[(18, 0)] = 100
# specify start and end
start = 21
end = 19
# compute the shortest path taking into account the edge weights
path = dijkstra_path(network.adjacency, weight, start, end)
# convert the path to network edges
edges = [(v, u) if not network.has_edge(u, v) else (u, v)
for u, v in pairwise(path)]
# make a plotter
plotter = NetworkPlotter(network, figsize=(8, 5))
# set default font sizes
plotter.defaults['vertex.fontsize'] = 6
plotter.defaults['edge.fontsize'] = 6
# draw the vertices
plotter.draw_vertices(
text='key',