City2Graph · Post-process a graph

Clean up and subset any graph object: remove isolated components, filter by distance from a center, clip to a polygon, and build isochrones.

This walkthrough mirrors the Graph Tools panel.

Before you begin

Have any graph object active — a street network, a proximity graph, or a morphological graph.

1. Choose an action

In Graph Tools, set the Action: Remove Isolated, Filter, Clip or Isochrone.

The Graph Tools action selector.

2. Remove isolated components

With Remove Isolated, press Apply to keep only the largest connected component, discarding stray fragments.

Keeping only the largest connected component.

3. Filter by distance

With Filter, set the Center object and a Threshold distance, then Apply to keep nodes within that distance.

Filtering the graph by distance from a center.

4. Clip to a polygon

With Clip, set the clip mesh and Apply to keep only the part of the graph inside the polygon.

Clipping the graph to a polygon.

5. Build an isochrone

With Isochrone, set the Isochrone Center, a Threshold and the Weight Attr (e.g. travel_time), then Apply to extract the reachable sub-network.

An isochrone sub-network from a center node.

Next steps

Continue with Export for GeoAI to take a graph into a GNN framework.