![]() ![]() One nice thing about overpy is that it detects the content type (i.e. Here you can see how we can translate the previous example with the overpy package import overpy api = overpy.Overpass() r = api.query(""" area (node(area) way(area) rel(area) ) out center """) coords = coords += coords += coords += import numpy as np import matplotlib.pyplot as plt # Collect coords into list coords = for element in data: if element = 'node': lon = element lat = element coords.append((lon, lat)) elif 'center' in element: lon = element lat = element coords.append((lon, lat)) # Convert coordinates into numpy array X = np.array(coords) plt.plot(X, X, 'o') plt.title('Biergarten in Germany') plt.xlabel('Longitude') plt.ylabel('Latitude') plt.axis('equal') plt.show()Īnother way to access the Overpass API with Python is by using the overpy package as a wrapper. In the case of node elements, the coordinates are simply under the lat, lon keys. Since we used the out center statement in our query, we get for each way and relation a center coordinate stored under the center key. ![]() Each element there contains a type key specifying if it is a node, way or relation and an id key. The data we care about is stored under the elements key. In this case we do not have to use urlencoding for our query since this is taken care of by requests.get and now we can store the data or directly use the data further. Let’s say you want to query nodes for cafes, then your query looks like this node() data = response.json() It takes some time getting used to, but luckily there is Overpass Turbo by Martin Raifer which comes in handy to interactively evaluate our queries directly in the browser. The Overpass API uses a custom query language to define the queries. #OPEN MAP API HOW TO#Now we’ll take a look how to load data from OSM. In simple terms, nodes are points on the maps (in latitude and longitude) as in the next image of a well documented bench in London. Many of the elements come with tags which describe specific features represented as key-value pairs. We have three basic components in the OSM data model, which are nodes, ways and relations which all come with an id. Quick Look at the OSM Data Modelīefore we start, we have to take a look at how OSM is structured. ![]() In this article we will only focus on the Overpass API which allows us to query specific data from the OSM data set. There are also different API possible such as the native OSM API or the Nominatim API. If you just need to work with a certain region you can use extracts in various formats such as the native. #OPEN MAP API DOWNLOAD#Of course you could download the whole Planet.osm but you would need to free up over 800 GB as of date of this article to have the whole data set sitting on your computer waiting to be analyzed. There are a number of ways to download map data from OpenStreetMap (OSM) as shown in their wiki. Biergarten in Germany, can you guess the big peak? ![]()
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