RasterPop
population.rasterpop.RasterPop(self, filepath)
Prepare raster population inputs for transport analysis.
This class is suited to working with rastered population data (e.g. gridded population estimates).
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
filepath |
Union[str, bytes, os.PathLike] | File path to population data | required |
Attributes
| Name | Type | Description |
|---|---|---|
| pop_gdf | gpd.GeoDataFrame | A geopandas dataframe of the input data, with gridded geometry. This is in the same CRS as the input raster data. |
| centroid_gdf | gpd.GeoDataFrame | A geopandas dataframe of grid centroids, converted to EPSG:4326 for transport analysis. |
Raises
| Type | Description |
|---|---|
| FileNotFoundError | When filepath is not a file or can not be found. |
Methods
| Name | Description |
|---|---|
| get_pop | Get population data. |
| plot | Plot population data. |
get_pop
population.rasterpop.RasterPop.get_pop(aoi_bounds, aoi_crs=None, round=False, threshold=None, var_name='population', urban_centre_bounds=None, urban_centre_crs=None, band=1)
Get population data.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
aoi_bounds |
Type[Polygon] | A shapely polygon defining the boundary of the area of interest. Assumed to be in the same CRS as the rastered population data. If it is different, set aoi_crs to the CRS of this boundary. |
required |
aoi_crs |
str | CRS string for aoi_bounds (e.g. “EPSG:4326”), by default None which means it is assumed to have the same CRS as the population data. |
None |
round |
bool | Round population estimates to the nearest whole integer. | False |
threshold |
Union[int, float] | Threshold population estimates, where values below the set threshold will be set to nan, by default None which means no thresholding will occur. | None |
var_name |
str | The variable name, by default “population” | 'population' |
urban_centre_bounds |
Type[Polygon] | Polygon defining an urban centre boundary, by default None meaning information concerning whether the grid resides within the urban centre will not be added. | None |
urban_centre_crs |
str | The urban centre polygon CRS, by default None meaning this is the same CRS as the input raster data. Only used when urban_centre_bounds is set. |
None |
band |
int | The band to select from the raster, by default 1. | 1 |
Returns
| Type | Description |
|---|---|
| gpd.GeoDataFrame | A geopandas dataframe of the input data, with gridded geometry. This is in the same CRS as the input raster data. |
| centroid_gdf | A geopandas dataframe of grid centroids, converted to EPSG:4326 for transport analysis. |
plot
population.rasterpop.RasterPop.plot(which='folium', save=None, **kwargs)
Plot population data.
Parameters
| Name | Type | Description | Default |
|---|---|---|---|
which |
str | Package to use for plotting. Must be one of {“matplotlib”, “cartopy”, “folium”}, by default “folium”. | 'folium' |
save |
str | Filepath to save file, with the file extension, by default None meaning a file will not be saved. | None |
kwargs |
dict | Extra arguments passed to plotting functions to configure the plot styling. See Notes for more support. | {} |
Returns
| Type | Description |
|---|---|
| Union[folium.Map, Type[GeoAxes], plt.Axes, None] | A folium map is returned when the folium backend is used. A matplotlib Axes object is returned when the matplotlib backend is used. A matplotlib/cartopy GeoAxes object is returned when the cartopy backend is used. None will be returned when saving to file. |
Raises
| Type | Description |
|---|---|
| ValueError | Unexpected value of which. |
| NotImplementedError | When plot is called without reading data. |
Notes
Calling help as follows will provide more insights on possible kwarg arguments for the valid plotting backends:
- Folium backend:
help(RasterPop._plot_folium) - Matplotlib backend:
help(RasterPop._plot_matplotlib) - Cartopy backend:
help(RasterPop._plot_cartopy)