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Vector density

vector_density(geodataframe, raster_profile, buffer_value=None, statistic='density')

Compute density of geometries within raster.

Parameters:

Name Type Description Default
geodataframe GeoDataFrame

The dataframe with vectors of which density is computed.

 required
base_raster_profile

Base raster profile to be used for determining the grid on which vectors are burned in. If None, the geometries and provided resolution value are used to compute grid.

 required
buffer_value Optional[float]

For adding a buffer around passed geometries before computing density.

 None
statistic Literal[density, count]

The statistic to use in density computation. Defaults to "density".

 'density'

Returns:

Type Description
ndarray

Computed density of vector data.
Source code in eis_toolkit/vector_processing/vector_density.py 
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@beartype
def vector_density(
    geodataframe: gpd.GeoDataFrame,
    raster_profile: Union[profiles.Profile, dict],
    buffer_value: Optional[float] = None,
    statistic: Literal["density", "count"] = "density",
) -> np.ndarray:
    """Compute density of geometries within raster.

    Args:
        geodataframe: The dataframe with vectors of which density is computed.
        base_raster_profile: Base raster profile to be used for determining
            the grid on which vectors are burned in. If None, the geometries
            and provided resolution value are used to compute grid.
        buffer_value: For adding a buffer around passed geometries before computing density.
        statistic: The statistic to use in density computation. Defaults to "density".

    Returns:
        Computed density of vector data.
    """
    out_raster_array = rasterize_vector(
        geodataframe=geodataframe,
        raster_profile=raster_profile,
        buffer_value=buffer_value,
        value_column=None,
        default_value=1.0,
        fill_value=0.0,
        merge_strategy="add",
    )
    max_count = np.max(out_raster_array)
    if statistic == "count" or np.isclose(max_count, 0.0):
        return out_raster_array
    else:
        return out_raster_array / max_count