7.8. Exploring the network on a notebookΒΆ

On this example we show how to use Folium to plot a network for different modes

We will need Folium for this example, and we will focus on creating a layer for each mode in the network, a layer for all links and a layer for all nodes

What we want is a map that looks a little like this

from PIL import Image
import matplotlib.pyplot as plt
img = Image.open('plot_network_image.png')
plt.imshow(img)
plot display

Out:

<matplotlib.image.AxesImage object at 0x7f18fe6b3c50>

# Imports

from uuid import uuid4
from tempfile import gettempdir
from os.path import join
from aequilibrae.utils.create_example import create_example
import folium

We create an empty project on an arbitrary folder

fldr = join(gettempdir(), uuid4().hex)

# Let's use the Nauru example project for display
project = create_example(fldr, 'nauru')

We grab all the links data as a Pandas dataframe so we can process it easier

links = project.network.links.data
nodes = project.network.nodes.data

# We create our Folium layers
network_links = folium.FeatureGroup("links")
network_nodes = folium.FeatureGroup("nodes")
car = folium.FeatureGroup("Car")
walk = folium.FeatureGroup("Walk")
bike = folium.FeatureGroup("Bike")
transit = folium.FeatureGroup("Transit")
layers = [network_links, network_nodes, car, walk, bike, transit]

# We do some Python magic to transform this dataset into the format required by Folium
# We are only getting link_id and link_type into the map, but we could get other pieces of info as well
for i, row in links.iterrows():
    points = row.geometry.to_wkt().replace('LINESTRING ', '').replace('(', '').replace(')', '').split(', ')
    points = '[[' + '],['.join([p.replace(' ', ', ') for p in points]) + ']]'
    # we need to take from x/y to lat/long
    points = [[x[1], x[0]] for x in eval(points)]

    _ = folium.vector_layers.PolyLine(points, popup=f'<b>link_id: {row.link_id}</b>', tooltip=f'{row.modes}',
                                      color='gray', weight=2).add_to(network_links)

    if 'w' in row.modes:
        _ = folium.vector_layers.PolyLine(points, popup=f'<b>link_id: {row.link_id}</b>', tooltip=f'{row.modes}',
                                             color='green', weight=4).add_to(walk)

    if 'b' in row.modes:
        _ = folium.vector_layers.PolyLine(points, popup=f'<b>link_id: {row.link_id}</b>', tooltip=f'{row.modes}',
                                             color='green', weight=4).add_to(bike)

    if 'c' in row.modes:
        _ = folium.vector_layers.PolyLine(points, popup=f'<b>link_id: {row.link_id}</b>', tooltip=f'{row.modes}',
                                             color='red', weight=4).add_to(car)

    if 't' in row.modes:
        _ = folium.vector_layers.PolyLine(points, popup=f'<b>link_id: {row.link_id}</b>', tooltip=f'{row.modes}',
                                             color='yellow', weight=4).add_to(transit)

# And now we get the nodes

for i, row in nodes.iterrows():
    point = (row.geometry.y, row.geometry.x)

    _ = folium.vector_layers.CircleMarker(point, popup=f'<b>link_id: {row.node_id}</b>', tooltip=f'{row.modes}',
                                          color='black', radius=5, fill=True, fillColor='black',
                                          fillOpacity=1.0).add_to(network_nodes)

We get the center of the region we are working with some SQL magic

curr = project.conn.cursor()
curr.execute('select avg(xmin), avg(ymin) from idx_links_geometry')
long, lat = curr.fetchone()
# We create the map
map_osm = folium.Map(location=[lat, long], zoom_start=14)

# add all layers
for layer in layers:
    layer.add_to(map_osm)

# And Add layer control before we display it
folium.LayerControl().add_to(map_osm)
map_osm
Make this Notebook Trusted to load map: File -> Trust Notebook