def test_migration_seed_data_correctly(self):
longitude = 120.1
latitude = 23.234
radius_km = 1
distance = 6371 * ACos(
Cos(Radians(latitude)) * Cos(Radians("lat")) *
Cos(Radians("lng") - Radians(longitude)) +
Sin(Radians(latitude)) * Sin(Radians("lat")))
factories = Factory.objects.annotate(distance=distance).filter(
distance__lt=radius_km)
self.assertEqual(
set([factory.name for factory in factories]),
set([
"既有違章工廠 No.2",
"既有違章工廠 No.3",
"既有違章工廠 No.8",
"既有違章工廠 No.9",
"既有違章工廠 No.10",
"既有違章工廠 No.11",
"既有違章工廠 No.12",
"既有違章工廠 No.13",
"既有違章工廠 No.22",
]),
)
def _get_nearby_factories(latitude, longitude, radius):
"""Return nearby factories based on position and search range."""
# ref: https://stackoverflow.com/questions/574691/mysql-great-circle-distance-haversine-formula
distance = 6371 * ACos(
Cos(Radians(latitude)) * Cos(Radians("lat")) *
Cos(Radians("lng") - Radians(longitude)) +
Sin(Radians(latitude)) * Sin(Radians("lat")))
radius_km = radius
ids = Factory.objects.annotate(distance=distance).only("id").filter(
distance__lt=radius_km).order_by("id")
if len(ids) > settings.MAX_FACTORY_PER_GET:
ids = _sample(ids, settings.MAX_FACTORY_PER_GET)
return (Factory.objects.filter(
id__in=[obj.id for obj in ids]).prefetch_related(
Prefetch('report_records',
queryset=ReportRecord.objects.only("created_at").all())
).prefetch_related(
Prefetch(
'images',
queryset=Image.objects.only("id").all())).prefetch_related(
Prefetch('documents',
queryset=Document.objects.only(
'created_at', 'display_status').all())).all())
def test_migration_seed_data_correctly():
longitude = 120.1
latitude = 23.234
radius_km = 1
distance = 6371 * ACos(
Cos(Radians(latitude)) * Cos(Radians("lat")) * Cos(Radians("lng") - Radians(longitude))
+ Sin(Radians(latitude)) * Sin(Radians("lat"))
)
factories = Factory.objects.annotate(distance=distance).filter(
distance__lt=radius_km,
)
assert (
list(factories.values_list('name', flat=True))
== Unordered([
"既有違章工廠 No.2",
"既有違章工廠 No.3",
"既有違章工廠 No.8",
"既有違章工廠 No.9",
"既有違章工廠 No.10",
"既有違章工廠 No.11",
"既有違章工廠 No.12",
"既有違章工廠 No.13",
"既有違章工廠 No.22",
])
)
def filter_cone_search(self, queryset, name, value):
"""
Executes cone search by annotating each target with separation distance from either the specified RA/Dec or
the RA/Dec of the specified target. Formula is from Wikipedia: https://en.wikipedia.org/wiki/Angular_distance
The result is converted to radians.
Cone search is preceded by a square search to reduce the search radius before annotating the queryset, in
order to make the query faster.
"""
if name == 'cone_search':
ra, dec, radius = value.split(',')
elif name == 'target_cone_search':
target_name, radius = value.split(',')
targets = Target.objects.filter(
Q(name__icontains=target_name)
| Q(aliases__name__icontains=target_name)).distinct()
if len(targets) == 1:
ra = targets[0].ra
dec = targets[0].dec
else:
return queryset.filter(name=None)
ra = float(ra)
dec = float(dec)
double_radius = float(radius) * 2
queryset = queryset.filter(ra__gte=ra - double_radius,
ra__lte=ra + double_radius,
dec__gte=dec - double_radius,
dec__lte=dec + double_radius)
separation = ExpressionWrapper(
180 * ACos((Sin(radians(dec)) * Sin(Radians('dec'))) +
(Cos(radians(dec)) * Cos(Radians('dec')) *
Cos(radians(ra) - Radians('ra')))) / Pi(),
FloatField())
return queryset.annotate(separation=separation).filter(
separation__lte=radius)
def cone_search_filter(queryset, ra, dec, radius):
"""
Executes cone search by annotating each target with separation distance from the specified RA/Dec.
Formula is from Wikipedia: https://en.wikipedia.org/wiki/Angular_distance
The result is converted to radians.
Cone search is preceded by a square search to reduce the search radius before annotating the queryset, in
order to make the query faster.
:param queryset: Queryset of Target objects
:type queryset: Target
:param ra: Right ascension of center of cone.
:type ra: float
:param dec: Declination of center of cone.
:type dec: float
:param radius: Radius of cone search in degrees.
:type radius: float
"""
ra = float(ra)
dec = float(dec)
radius = float(radius)
double_radius = radius * 2
queryset = queryset.filter(ra__gte=ra - double_radius,
ra__lte=ra + double_radius,
dec__gte=dec - double_radius,
dec__lte=dec + double_radius)
separation = ExpressionWrapper(
180 * ACos((Sin(radians(dec)) * Sin(Radians('dec'))) +
(Cos(radians(dec)) * Cos(Radians('dec')) *
Cos(radians(ra) - Radians('ra')))) / Pi(), FloatField())
return queryset.annotate(separation=separation).filter(
separation__lte=radius)
def perimeter(self,
mid_point,
radius,
latitude='latitude',
longitude='longitude'):
"""
Returns a query set of locations in a specified radius (using the Haversine formula).
:param mid_point: middle point coordinates of search radius (e.g. tuple of floats)
:param radius: search radius in km (default) or miles depending on DISTANCE_UNIT
:param latitude: query selector for latitude
:param longitude: query selector for longitude
:return: Annotated query set of found locations
"""
earth_radius = dict(EARTH_RADIUS_CHOICES).get(self.DISTANCE_UNIT)
distance = (earth_radius * ACos(
Cos(Radians(latitude)) * Cos(Radians(mid_point[0])) *
Cos(Radians(mid_point[1]) - Radians(longitude)) +
Sin(Radians(latitude)) * Sin(Radians(mid_point[0]))))
return self.annotate(distance=distance).filter(distance__lte=radius)