momepy.gamma#
- momepy.gamma(graph, radius=5, name='gamma', distance=None, verbose=True)[source]#
Calculates connectivity gamma index for subgraph around each node if radius is set, or for whole graph, if
radius=None
.Subgraph is generated around each node within set radius. If
distance=None
, radius will define topological distance, otherwise it uses values indistance
attribute.\[\alpha=\frac{e}{3(v-2)}\]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
Graph representing street network. Ideally generated from GeoDataFrame using
momepy.gdf_to_nx()
- radius: int
Include all neighbors of distance <= radius from n
- namestr, optional
calculated attribute name
- distancestr, optional
Use specified edge data key as distance. For example, setting
distance=’weight’
will use the edgeweight
to measure the distance from the node n.- verbosebool (default True)
if True, shows progress bars in loops and indication of steps
- Returns
- Graph
networkx.Graph if radius is set
- float
gamma index for graph if
radius=None
Examples
>>> network_graph = mm.gamma(network_graph, radius=3)