momepy.form_factor¶

momepy.form_factor(geometry, height)[source]¶

Calculates the form factor of each object given its geometry and height.

\[surface \over {volume^{2 \over 3}}\]

where

\[surface = (perimeter * height) + area\]

Adapted from [Bourdic et al., 2012].

Parameters:¶

geometry : GeoDataFrame | GeoSeries¶

A GeoDataFrame or GeoSeries containing polygons to analyse.

height : NDArray[np.float64] | Series¶

array of heights

Return type:¶

Series

Examples

>>> path = momepy.datasets.get_path("bubenec")
>>> buildings = geopandas.read_file(path, layer="buildings")

Synthesize some building height information.

>>> import numpy as np
>>> rng = np.random.default_rng(seed=42)
>>> height = rng.integers(low=9, high=30, size=len(buildings))

>>> momepy.form_factor(buildings, height)
0      5.588952
1      8.403204
2      5.149302
3      5.381587
4      5.030861
        ...
139    6.039771
140    5.904980
141    5.508910
142    5.869335
143    5.378663
Name: form_factor, Length: 144, dtype: float64