Quick Start

This section provides introductory examples to demonstrate the core workflow of using osm2gmns for generating, processing, and exporting transportation networks.

osm2gmns processes network data from local OpenStreetMap files (.osm, .xml, or .pbf formats). Therefore, the first step is always to download the OSM data for your region of interest. Several methods exist for this, detailed in the Get OSM Data section.

In this guide, we use the area around Arizona State University, Tempe Campus as an example to introduce some major functions in osm2gmns. The downloaded osm file is named as asu.osm.

Basic Network Generation

Load a network from an OSM file and export it to GMNS-compliant CSV files.

>>> import osm2gmns as og
>>> net = og.getNetFromFile('asu.osm')
>>> og.outputNetToCSV(net)

By default, getNetFromFile extracts the drivable network (mode_types=’auto’). In the example, the output folder is set as the current working directory. Users can specify the output folder by using the argument output_folder. The output files include node.csv and link.csv, which contain node and link information respectively.

Consolidate Intersections

In OpenStreetMap, large intersections are often mapped using multiple nodes. For many traffic analysis tasks, it’s beneficial to represent such intersections as single nodes. The consolidateComplexIntersections function achieves this, typically focusing on signalized junctions.

>>> net = og.getNetFromFile('asu.osm')
>>> og.consolidateComplexIntersections(net, auto_identify=True)
>>> og.outputNetToCSV(net)

Complex intersection consolidation

The resulting network can be visualized using tools like QGIS or NeXTA to inspect the consolidated intersections.

Network Types and POI

osm2gmns supports five different mode types, including auto, bike, walk, railway, aeroway. Users can get different types of networks by specifying the argument mode_types (default: auto).

>>> # obtain the network for bike
>>> net = og.getNetFromFile('asu.osm', mode_types='bike')
>>> # obtain the network for walk and bike
>>> net = og.getNetFromFile('asu.osm', mode_types=['walk','bike'])
>>> # obtain the network for auto, railway and aeroway
>>> net = og.getNetFromFile('asu.osm', mode_types=['auto','railway','aeroway'])

Obtain POIs (Point of Interest) from osm map data.

>>> net = og.getNetFromFile('asu.osm', POI=True)

If POI=True is used, outputNetToCSV will generate an additional poi.csv file alongside node.csv and link.csv.

Network with POIs

Generate Multi-Resolution Networks

Multi-resolution (MRM) functionalities are currently not available in v1.x. For MRM, users can use the latest v0.x. Check the v0.x user’s guide for details.