Project from OpenStreetMap

In this example, we show how to create an empty project and populate it with a network from OpenStreetMap.

This time we will use Folium to visualize the network.

# Imports
from uuid import uuid4
from tempfile import gettempdir
from os.path import join
from aequilibrae import Project
import folium

We create an empty project on an arbitrary folder

fldr = join(gettempdir(), uuid4().hex)
project = Project()
project.new(fldr)

Now we can download the network from any place in the world (as long as you have memory for all the download and data wrangling that will be done).

We can create from a bounding box or a named place. For the sake of this example, we will choose the small nation of Nauru.

project.network.create_from_osm(place_name="Nauru")

We can also choose to create a model from a polygon (which must be in EPSG:4326) Or from a Polygon defined by a bounding box, for example.

# project.network.create_from_osm(model_area=box(-112.185, 36.59, -112.179, 36.60))

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

links = project.network.links.data

We create a Folium layer

network_links = folium.FeatureGroup("links")

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.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)]

    line = folium.vector_layers.PolyLine(
        points, popup=f"<b>link_id: {row.link_id}</b>", tooltip=f"{row.link_type}", color="blue", weight=10
    ).add_to(network_links)

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()

map_osm = folium.Map(location=[lat, long], zoom_start=14)
network_links.add_to(map_osm)
folium.LayerControl().add_to(map_osm)
map_osm

project.close()