geo.py

gistfile1.py

import geopy
from geopy.distance import vincenty


def bounding_box_coordinates(location, radius):
    '''
    Given a latitude and longitude in degrees as a tuple and a radius in km
    calculates the bounding box coordinates using the vincenty formula.
    '''
    origin = geopy.Point(*location)

    COMPASS_BEARING = {
        'NORTH': 0,
        'EAST': 90,
        'SOUTH': 180,
        'WEST': 270}

    max_lat = vincenty(kilometers=radius).destination(
        origin, COMPASS_BEARING['NORTH']).latitude
    min_lat = vincenty(kilometers=radius).destination(
        origin, COMPASS_BEARING['SOUTH']).latitude
    max_long = vincenty(kilometers=radius).destination(
        origin, COMPASS_BEARING['EAST']).longitude
    min_long = vincenty(kilometers=radius).destination(
        origin, COMPASS_BEARING['WEST']).longitude
    locations = (
        min_lat,
        min_long,
        max_lat,
        max_long)
    return locations


def bounduary_filter(center, location, radius=1):
    '''
    Given the center of the bounding circle and the location on degrees as
    tuples it calculates if the location is within the bounduary radius given
    in kilometers.
    '''
    distance = geopy.distance.vincenty(
        geopy.Point(*center),
        geopy.Point(*location)
    ).kilometers
    return distance <= radius


print bounduary_filter((40.4183, -3.7028), (40.4093, -3.7028))