def test_radius_for_rectangle(self):
"""
Tests the function calculate_polygon_radius_km for a rectangle.
"""
rectangle = Location.objects.get(pk=3)
actual = shapes.calculate_polygon_radius_km(rectangle.geom)
point = shapes.reverse_coordinate_order(rectangle.geom.centroid)
expected = vincenty(point, (0, 1)).kilometers
self.assertEqual(actual, expected)
def test_radius_for_polygon(self):
"""
Tests the function calculate_polygon_radius_km for a nonrectangular
polygon.
"""
polygon = Location.objects.get(pk=7)
actual = shapes.calculate_polygon_radius_km(polygon.geom)
point = shapes.reverse_coordinate_order(polygon.geom.centroid)
expected = vincenty(point, (8, 0)).kilometers
self.assertEqual(actual, expected)
def radius_km(self):
"""
If the Location is a Circle, Rectangle, Polygon, or Multipolygon,
returns the distance in kilometers between the geometry's centroid and
the point on the geometry farthest from the centroid. Otherwise returns
None.
"""
if self.shape is 'Circle':
return units.meters_to_km(self.buffer_m)
elif self.shape is 'Rectangle' or self.shape is 'Polygon':
return shapes.calculate_polygon_radius_km(self.geom)
elif self.shape is 'MultiPolygon':
return shapes.calculate_multipoly_radius_km(self.geom)
else:
return None