OSMnx · Clean up the graph

Project the Burjassot network to a metric CRS, convert between graph representations, consolidate intersections, and trim the network to a study area.

This walkthrough mirrors the Graph Operations panel.

Before you begin

Download a network first (see Download a street network) and keep it active.

1. Project to a metric CRS

Fresh downloads are in geographic coordinates (degrees). In Graph Operations, press Project Graph to reproject to a local UTM zone so that lengths and areas are in meters.

Project Graph reprojects the network to UTM.

2. Convert representations

Use the conversion buttons as your analysis requires:

To Undirected — collapse two-way streets into single edges (needed for orientation statistics).
To DiGraph — a simple directed graph keyed by length.
Graph → GDFs / GDFs → Graph — round-trip through GeoDataFrames for external editing.

3. Consolidate intersections

Complex junctions are often modelled as several nearby nodes. Set the Tolerance (default 10 m) and press Consolidate Intersections to merge them into single nodes — useful before centrality analysis.

Consolidating intersections with a 10 m tolerance.

4. Truncate to a study area

Truncate by Distance — keep only nodes within a network distance of a source node.
Truncate by BBox / Polygon — clip to a rectangle or a polygon object.

Truncating the network by distance from a source node.

5. Keep the largest component

Press Largest Component to drop disconnected fragments and keep one contiguous network.

Largest Component removes disconnected fragments.

Next steps

Continue with Add edge attributes to compute lengths, speeds and travel times.