Source code for trackintel.preprocessing.filter

[docs] def spatial_filter(source, areas, method="within", re_project=False): """ Filter a GeoDataFrame on a geo extent. Parameters ---------- source : GeoDataFrame The source feature to perform the spatial filtering areas : GeoDataFrame The areas used to perform the spatial filtering. Note, you can have multiple Polygons and it will return all the features intersect with ANY of those geometries. method : {'within', 'intersects', 'crosses'}, optional The method to filter the 'source' GeoDataFrame, by default 'within' - `within`: return instances in 'source' where no points of these instances lies in the exterior of the 'areas' and at least one point of the interior of these instances lies in the interior of 'areas'. - `intersects`: return instances in 'source' where the boundary or interior of these instances intersect in any way with those of the 'areas' - `crosses`: return instances in 'source' where the interior of these instances intersects the interior of the 'areas' but does not contain it, and the dimension of the intersection is less than the dimension of the one of the 'areas'. re_project : bool, default False If this is set to True, the 'source' will be projected to the coordinate reference system of 'areas' Returns ------- GeoDataFrame A new GeoDataFrame containing the features after the spatial filtering. Examples -------- >>> sp.spatial_filter(areas, method="within", re_project=False) """ gdf = source.copy() if re_project: init_crs = gdf = gdf.to_crs( # build spatial index for pre filtering source_sindex = gdf.sindex possible_matches_index = [] for other in areas.itertuples(): bounds = other.geometry.bounds c = list(source_sindex.intersection(bounds)) possible_matches_index += c # Get unique candidates unique_candidate_matches = list(set(possible_matches_index)) possible_matches = gdf.iloc[unique_candidate_matches] # get final result if method == "within": ret_gdf = possible_matches.loc[possible_matches.within(areas.unary_union)] elif method == "intersects": ret_gdf = possible_matches.loc[possible_matches.intersects(areas.unary_union)] elif method == "crosses": ret_gdf = possible_matches.loc[possible_matches.crosses(areas.unary_union)] else: raise AttributeError( "method unknown. We only support ['within', 'intersects', 'crosses']. " f"You passed {method}" ) if re_project: return ret_gdf.to_crs(init_crs) else: return ret_gdf