def get_distance(self, dist_val, lookup_type):
"""
Returns a distance number in units of the field. For example, if
`D(km=1)` was passed in and the units of the field were in meters,
then 1000 would be returned.
"""
# Getting the distance parameter and any options.
if len(dist_val) == 1: dist, option = dist_val[0], None
else: dist, option = dist_val
if isinstance(dist, Distance):
if self.geodetic:
# Won't allow Distance objects w/DWithin lookups on PostGIS.
if SpatialBackend.postgis and lookup_type == 'dwithin':
raise TypeError('Only numeric values of degree units are allowed on geographic DWithin queries.')
# Spherical distance calculation parameter should be in meters.
dist_param = dist.m
else:
dist_param = getattr(dist, Distance.unit_attname(self._unit_name))
else:
# Assuming the distance is in the units of the field.
dist_param = dist
if SpatialBackend.postgis and self.geodetic and lookup_type != 'dwithin' and option == 'spheroid':
# On PostGIS, by default `ST_distance_sphere` is used; but if the
# accuracy of `ST_distance_spheroid` is needed than the spheroid
# needs to be passed to the SQL stored procedure.
return [gqn(self._spheroid), dist_param]
else:
return [dist_param]
def get_distance(self, dist_val, lookup_type):
"""
Returns a distance number in units of the field. For example, if
`D(km=1)` was passed in and the units of the field were in meters,
then 1000 would be returned.
"""
# Getting the distance parameter and any options.
if len(dist_val) == 1: dist, option = dist_val[0], None
else: dist, option = dist_val
if isinstance(dist, Distance):
if self.geodetic:
# Won't allow Distance objects w/DWithin lookups on PostGIS.
if SpatialBackend.postgis and lookup_type == 'dwithin':
raise TypeError(
'Only numeric values of degree units are allowed on geographic DWithin queries.'
)
# Spherical distance calculation parameter should be in meters.
dist_param = dist.m
else:
dist_param = getattr(dist,
Distance.unit_attname(self._unit_name))
else:
# Assuming the distance is in the units of the field.
dist_param = dist
if SpatialBackend.postgis and self.geodetic and lookup_type != 'dwithin' and option == 'spheroid':
# On PostGIS, by default `ST_distance_sphere` is used; but if the
# accuracy of `ST_distance_spheroid` is needed than the spheroid
# needs to be passed to the SQL stored procedure.
return [gqn(self._spheroid), dist_param]
else:
return [dist_param]