cityImage.dual_gdf#

cityImage.dual_gdf(nodes_gdf, edges_gdf, epsg, oneway=False, angle=None)[source]#

It creates two dataframes that are later exploited to generate the dual graph of a street network. The nodes_dual gdf contains edges centroids; the edges_dual gdf, instead, contains links between the street segment centroids. Those dual edges link real street segments that share a junction. The centroids are stored with the original edge edgeID, while the dual edges are associated with several attributes computed on the original street segments (distance between centroids, deflection angle).

Parameters:

  • nodes_gdf (Point GeoDataFrame) – The nodes (junctions) GeoDataFrame.

  • edges_gdf (LineString GeoDataFrame) – The street segments GeoDataFrame.

  • epsg (int) – Epsg of the area considered

  • oneway (boolean) – When true, the function takes into account the direction and therefore it may ignore certain links whereby vehichular movement is not allowed in a certain direction.

  • angle (string {'degree', 'radians'}) – It indicates how to express the angle of deflection.

Returns:

nodes_dual, edges_dual – The dual nodes and edges GeoDataFrames.

Return type:

tuple of GeoDataFrames