def test_geography_value(self):
p = Polygon(((1, 1), (1, 2), (2, 2), (2, 1), (1, 1)))
area = (
City.objects.annotate(
a=functions.Area(Value(p, GeometryField(srid=4326, geography=True)))
)
.first()
.a
)
self.assertAlmostEqual(area.sq_km, 12305.1, 0)
def test_area_lookups(self):
# Create projected countries so the test works on all backends.
CountryWebMercator.objects.bulk_create(
CountryWebMercator(name=c.name, mpoly=c.mpoly.transform(3857, clone=True))
for c in Country.objects.all()
)
qs = CountryWebMercator.objects.annotate(area=functions.Area('mpoly'))
self.assertEqual(qs.get(area__lt=Area(sq_km=500000)), CountryWebMercator.objects.get(name='New Zealand'))
with self.assertRaisesMessage(ValueError, 'AreaField only accepts Area measurement objects.'):
qs.get(area__lt=500000)
def test_area_with_regular_aggregate(self):
# Create projected country objects, for this test to work on all backends.
for c in Country.objects.all():
CountryWebMercator.objects.create(name=c.name, mpoly=c.mpoly)
# Test in projected coordinate system
qs = CountryWebMercator.objects.annotate(area_sum=Sum(functions.Area('mpoly')))
for c in qs:
result = c.area_sum
# If the result is a measure object, get value.
if isinstance(result, Area):
result = result.sq_m
self.assertAlmostEqual((result - c.mpoly.area) / c.mpoly.area, 0)
def test_area_with_regular_aggregate(self):
# Create projected country objects, for this test to work on all backends.
for c in Country.objects.all():
CountryWebMercator.objects.create(name=c.name, mpoly=c.mpoly.transform(3857, clone=True))
# Test in projected coordinate system
qs = CountryWebMercator.objects.annotate(area_sum=Sum(functions.Area('mpoly')))
# Some backends (e.g. Oracle) cannot group by multipolygon values, so
# defer such fields in the aggregation query.
for c in qs.defer('mpoly'):
result = c.area_sum
# If the result is a measure object, get value.
if isinstance(result, Area):
result = result.sq_m
self.assertAlmostEqual((result - c.mpoly.area) / c.mpoly.area, 0)
