momepy.Count#

momepy.Count(left, right, left_id, right_id, weighted=False)[source]#

Calculate the number of elements within an aggregated structure. Aggregated structures can typically be blocks, street segments, or street nodes (their snapepd objects). The right gdf has to have a unique ID of aggregated structures assigned before hand (e.g. using momepy.get_network_id()). If weighted=True, the number of elements will be divided by the area of length (based on geometry type) of aggregated elements, to return relative value.

\[\sum_{i \in aggr} (n_i);\space \frac{\sum_{i \in aggr} (n_i)}{area_{aggr}}\]

Adapted from [Hermosilla et al., 2012] and [Feliciotti, 2018].

Parameters:

leftGeoDataFrame: A GeoDataFrame containing aggregation to analyse.
rightGeoDataFrame: A GeoDataFrame containing objects to analyse.
left_idstr: The name of the column where unique ID in the left gdf is stored.
right_idstr: The name of the column where unique ID of aggregation in the right gdf is stored.
weightedbool (default False): If True, count will be divided by the area or length.

Attributes:

seriesSeries: A Series containing resulting values.
leftGeoDataFrame: The original left GeoDataFrame.
rightGeoDataFrame: The original right GeoDataFrame.
left_idSeries: A Series containing used left ID.
right_idSeries: A Series containing used right ID.
weightedbool: True if the weighted value was used.

Examples

>>> blocks_df['buildings_count'] = mm.Count(blocks_df,
...                                         buildings_df,
...                                         'bID',
...                                         'bID',
...                                         weighted=True).series