momepy.edge_node_ratio#

momepy.edge_node_ratio(graph, radius=5, name='edge_node_ratio', distance=None, verbose=True)[source]#

Calculates edge / node ratio for subgraph around each node if radius is set, or for whole graph, if radius=None. A subgraph is generated around each node within set radius. If distance=None, radius will define topological distance, otherwise it uses values in distance attribute.

\[\alpha=e/v\]

where \(e\) is the number of edges in subgraph and \(v\) is the number of nodes in subgraph.

Adapted from [Dibble et al., 2017].

Parameters
graphnetworkx.Graph

A Graph representing a street network. Ideally generated from GeoDataFrame using momepy.gdf_to_nx().

radius: int

Include all neighbors of distance <= radius from n.

namestr, optional

The calculated attribute name.

distancestr, optional

Use specified edge data key as distance. For example, setting distance=’weight’ will use the edge weight to measure the distance from the node n.

verbosebool (default True)

If True, shows progress bars in loops and indication of steps.

Returns
netxGraph

A networkx.Graph object if radius is set.

float

The edge / node ratio for the graph if radius=None.

Examples

>>> network_graph = mm.edge_node_ratio(network_graph, radius=3)