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from __future__ import unicode_literals
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from unittest import skipUnless
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from django . db import connection
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from django . db . models import Q
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from django . contrib . gis . geos import HAS_GEOS
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from django . contrib . gis . measure import D # alias for Distance
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from django . contrib . gis . tests . utils import (
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HAS_SPATIAL_DB , mysql , oracle , postgis , spatialite , no_oracle , no_spatialite
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)
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from django . test import TestCase
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if HAS_GEOS and HAS_SPATIAL_DB :
from django . contrib . gis . geos import GEOSGeometry , LineString
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from . models import ( AustraliaCity , Interstate , SouthTexasInterstate ,
SouthTexasCity , SouthTexasCityFt , CensusZipcode , SouthTexasZipcode )
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@skipUnless ( HAS_GEOS and HAS_SPATIAL_DB and not mysql ,
" Geos and spatial db (not mysql) are required. " )
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class DistanceTest ( TestCase ) :
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if HAS_GEOS and HAS_SPATIAL_DB :
# A point we are testing distances with -- using a WGS84
# coordinate that'll be implicitly transormed to that to
# the coordinate system of the field, EPSG:32140 (Texas South Central
# w/units in meters)
stx_pnt = GEOSGeometry ( ' POINT (-95.370401017314293 29.704867409475465) ' , 4326 )
# Another one for Australia
au_pnt = GEOSGeometry ( ' POINT (150.791 -34.4919) ' , 4326 )
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def get_names ( self , qs ) :
cities = [ c . name for c in qs ]
cities . sort ( )
return cities
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def test_init ( self ) :
"""
Test initialization of distance models .
"""
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self . assertEqual ( 9 , SouthTexasCity . objects . count ( ) )
self . assertEqual ( 9 , SouthTexasCityFt . objects . count ( ) )
self . assertEqual ( 11 , AustraliaCity . objects . count ( ) )
self . assertEqual ( 4 , SouthTexasZipcode . objects . count ( ) )
self . assertEqual ( 4 , CensusZipcode . objects . count ( ) )
self . assertEqual ( 1 , Interstate . objects . count ( ) )
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self . assertEqual ( 1 , SouthTexasInterstate . objects . count ( ) )
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@no_spatialite
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def test_dwithin ( self ) :
"""
Test the ` dwithin ` lookup type .
"""
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# Distances -- all should be equal (except for the
# degree/meter pair in au_cities, that's somewhat
# approximate).
tx_dists = [ ( 7000 , 22965.83 ) , D ( km = 7 ) , D ( mi = 4.349 ) ]
au_dists = [ ( 0.5 , 32000 ) , D ( km = 32 ) , D ( mi = 19.884 ) ]
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# Expected cities for Australia and Texas.
tx_cities = [ ' Downtown Houston ' , ' Southside Place ' ]
au_cities = [ ' Mittagong ' , ' Shellharbour ' , ' Thirroul ' , ' Wollongong ' ]
# Performing distance queries on two projected coordinate systems one
# with units in meters and the other in units of U.S. survey feet.
for dist in tx_dists :
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if isinstance ( dist , tuple ) :
dist1 , dist2 = dist
else :
dist1 = dist2 = dist
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qs1 = SouthTexasCity . objects . filter ( point__dwithin = ( self . stx_pnt , dist1 ) )
qs2 = SouthTexasCityFt . objects . filter ( point__dwithin = ( self . stx_pnt , dist2 ) )
for qs in qs1 , qs2 :
self . assertEqual ( tx_cities , self . get_names ( qs ) )
# Now performing the `dwithin` queries on a geodetic coordinate system.
for dist in au_dists :
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if isinstance ( dist , D ) and not oracle :
type_error = True
else :
type_error = False
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if isinstance ( dist , tuple ) :
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if oracle :
dist = dist [ 1 ]
else :
dist = dist [ 0 ]
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# Creating the query set.
qs = AustraliaCity . objects . order_by ( ' name ' )
if type_error :
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# A ValueError should be raised on PostGIS when trying to pass
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# Distance objects into a DWithin query using a geodetic field.
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self . assertRaises ( ValueError , AustraliaCity . objects . filter ( point__dwithin = ( self . au_pnt , dist ) ) . count )
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else :
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self . assertListEqual ( au_cities , self . get_names ( qs . filter ( point__dwithin = ( self . au_pnt , dist ) ) ) )
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def test_distance_projected ( self ) :
"""
Test the ` distance ` GeoQuerySet method on projected coordinate systems .
"""
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# The point for La Grange, TX
lagrange = GEOSGeometry ( ' POINT(-96.876369 29.905320) ' , 4326 )
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# Reference distances in feet and in meters. Got these values from
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# using the provided raw SQL statements.
# SELECT ST_Distance(point, ST_Transform(ST_GeomFromText('POINT(-96.876369 29.905320)', 4326), 32140)) FROM distapp_southtexascity;
m_distances = [ 147075.069813 , 139630.198056 , 140888.552826 ,
138809.684197 , 158309.246259 , 212183.594374 ,
70870.188967 , 165337.758878 , 139196.085105 ]
# SELECT ST_Distance(point, ST_Transform(ST_GeomFromText('POINT(-96.876369 29.905320)', 4326), 2278)) FROM distapp_southtexascityft;
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# Oracle 11 thinks this is not a projected coordinate system, so it's s
# not tested.
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ft_distances = [ 482528.79154625 , 458103.408123001 , 462231.860397575 ,
455411.438904354 , 519386.252102563 , 696139.009211594 ,
232513.278304279 , 542445.630586414 , 456679.155883207 ]
# Testing using different variations of parameters and using models
# with different projected coordinate systems.
dist1 = SouthTexasCity . objects . distance ( lagrange , field_name = ' point ' )
dist2 = SouthTexasCity . objects . distance ( lagrange ) # Using GEOSGeometry parameter
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if spatialite or oracle :
dist_qs = [ dist1 , dist2 ]
else :
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dist3 = SouthTexasCityFt . objects . distance ( lagrange . ewkt ) # Using EWKT string parameter.
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dist4 = SouthTexasCityFt . objects . distance ( lagrange )
dist_qs = [ dist1 , dist2 , dist3 , dist4 ]
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# Original query done on PostGIS, have to adjust AlmostEqual tolerance
# for Oracle.
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tol = 2 if oracle else 5
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# Ensuring expected distances are returned for each distance queryset.
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for qs in dist_qs :
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for i , c in enumerate ( qs ) :
self . assertAlmostEqual ( m_distances [ i ] , c . distance . m , tol )
self . assertAlmostEqual ( ft_distances [ i ] , c . distance . survey_ft , tol )
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@no_spatialite
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def test_distance_geodetic ( self ) :
"""
Test the ` distance ` GeoQuerySet method on geodetic coordinate systems .
"""
tol = 2 if oracle else 5
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# Testing geodetic distance calculation with a non-point geometry
# (a LineString of Wollongong and Shellharbour coords).
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ls = LineString ( ( ( 150.902 , - 34.4245 ) , ( 150.87 , - 34.5789 ) ) )
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if oracle or connection . ops . geography :
# Reference query:
# SELECT ST_distance_sphere(point, ST_GeomFromText('LINESTRING(150.9020 -34.4245,150.8700 -34.5789)', 4326)) FROM distapp_australiacity ORDER BY name;
distances = [ 1120954.92533513 , 140575.720018241 , 640396.662906304 ,
60580.9693849269 , 972807.955955075 , 568451.8357838 ,
40435.4335201384 , 0 , 68272.3896586844 , 12375.0643697706 , 0 ]
qs = AustraliaCity . objects . distance ( ls ) . order_by ( ' name ' )
for city , distance in zip ( qs , distances ) :
# Testing equivalence to within a meter.
self . assertAlmostEqual ( distance , city . distance . m , 0 )
else :
# PostGIS 1.4 and below is limited to disance queries only
# to/from point geometries, check for raising of ValueError.
self . assertRaises ( ValueError , AustraliaCity . objects . distance , ls )
self . assertRaises ( ValueError , AustraliaCity . objects . distance , ls . wkt )
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# Got the reference distances using the raw SQL statements:
# SELECT ST_distance_spheroid(point, ST_GeomFromText('POINT(151.231341 -33.952685)', 4326), 'SPHEROID["WGS 84",6378137.0,298.257223563]') FROM distapp_australiacity WHERE (NOT (id = 11));
# SELECT ST_distance_sphere(point, ST_GeomFromText('POINT(151.231341 -33.952685)', 4326)) FROM distapp_australiacity WHERE (NOT (id = 11)); st_distance_sphere
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if connection . ops . postgis and connection . ops . proj_version_tuple ( ) > = ( 4 , 7 , 0 ) :
# PROJ.4 versions 4.7+ have updated datums, and thus different
# distance values.
spheroid_distances = [ 60504.0628957201 , 77023.9489850262 , 49154.8867574404 ,
90847.4358768573 , 217402.811919332 , 709599.234564757 ,
640011.483550888 , 7772.00667991925 , 1047861.78619339 ,
1165126.55236034 ]
sphere_distances = [ 60580.9693849267 , 77144.0435286473 , 49199.4415344719 ,
90804.7533823494 , 217713.384600405 , 709134.127242793 ,
639828.157159169 , 7786.82949717788 , 1049204.06569028 ,
1162623.7238134 ]
else :
spheroid_distances = [ 60504.0628825298 , 77023.948962654 , 49154.8867507115 ,
90847.435881812 , 217402.811862568 , 709599.234619957 ,
640011.483583758 , 7772.00667666425 , 1047861.7859506 ,
1165126.55237647 ]
sphere_distances = [ 60580.7612632291 , 77143.7785056615 , 49199.2725132184 ,
90804.4414289463 , 217712.63666124 , 709131.691061906 ,
639825.959074112 , 7786.80274606706 , 1049200.46122281 ,
1162619.7297006 ]
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# Testing with spheroid distances first.
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hillsdale = AustraliaCity . objects . get ( name = ' Hillsdale ' )
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qs = AustraliaCity . objects . exclude ( id = hillsdale . id ) . distance ( hillsdale . point , spheroid = True )
for i , c in enumerate ( qs ) :
self . assertAlmostEqual ( spheroid_distances [ i ] , c . distance . m , tol )
if postgis :
# PostGIS uses sphere-only distances by default, testing these as well.
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qs = AustraliaCity . objects . exclude ( id = hillsdale . id ) . distance ( hillsdale . point )
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for i , c in enumerate ( qs ) :
self . assertAlmostEqual ( sphere_distances [ i ] , c . distance . m , tol )
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@no_oracle # Oracle already handles geographic distance calculation.
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def test_distance_transform ( self ) :
"""
Test the ` distance ` GeoQuerySet method used with ` transform ` on a geographic field .
"""
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# Normally you can't compute distances from a geometry field
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# that is not a PointField (on PostGIS 1.4 and below).
if not connection . ops . geography :
self . assertRaises ( ValueError , CensusZipcode . objects . distance , self . stx_pnt )
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# We'll be using a Polygon (created by buffering the centroid
# of 77005 to 100m) -- which aren't allowed in geographic distance
# queries normally, however our field has been transformed to
# a non-geographic system.
z = SouthTexasZipcode . objects . get ( name = ' 77005 ' )
# Reference query:
# SELECT ST_Distance(ST_Transform("distapp_censuszipcode"."poly", 32140), ST_GeomFromText('<buffer_wkt>', 32140)) FROM "distapp_censuszipcode";
dists_m = [ 3553.30384972258 , 1243.18391525602 , 2186.15439472242 ]
# Having our buffer in the SRID of the transformation and of the field
# -- should get the same results. The first buffer has no need for
# transformation SQL because it is the same SRID as what was given
# to `transform()`. The second buffer will need to be transformed,
# however.
buf1 = z . poly . centroid . buffer ( 100 )
buf2 = buf1 . transform ( 4269 , clone = True )
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ref_zips = [ ' 77002 ' , ' 77025 ' , ' 77401 ' ]
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for buf in [ buf1 , buf2 ] :
qs = CensusZipcode . objects . exclude ( name = ' 77005 ' ) . transform ( 32140 ) . distance ( buf )
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self . assertListEqual ( ref_zips , self . get_names ( qs ) )
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for i , z in enumerate ( qs ) :
self . assertAlmostEqual ( z . distance . m , dists_m [ i ] , 5 )
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def test_distance_lookups ( self ) :
"""
Test the ` distance_lt ` , ` distance_gt ` , ` distance_lte ` , and ` distance_gte ` lookup types .
"""
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# Retrieving the cities within a 20km 'donut' w/a 7km radius 'hole'
# (thus, Houston and Southside place will be excluded as tested in
# the `test02_dwithin` above).
qs1 = SouthTexasCity . objects . filter ( point__distance_gte = ( self . stx_pnt , D ( km = 7 ) ) ) . filter ( point__distance_lte = ( self . stx_pnt , D ( km = 20 ) ) )
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# Can't determine the units on SpatiaLite from PROJ.4 string, and
# Oracle 11 incorrectly thinks it is not projected.
if spatialite or oracle :
dist_qs = ( qs1 , )
else :
qs2 = SouthTexasCityFt . objects . filter ( point__distance_gte = ( self . stx_pnt , D ( km = 7 ) ) ) . filter ( point__distance_lte = ( self . stx_pnt , D ( km = 20 ) ) )
dist_qs = ( qs1 , qs2 )
for qs in dist_qs :
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cities = self . get_names ( qs )
self . assertEqual ( cities , [ ' Bellaire ' , ' Pearland ' , ' West University Place ' ] )
# Doing a distance query using Polygons instead of a Point.
z = SouthTexasZipcode . objects . get ( name = ' 77005 ' )
qs = SouthTexasZipcode . objects . exclude ( name = ' 77005 ' ) . filter ( poly__distance_lte = ( z . poly , D ( m = 275 ) ) )
self . assertEqual ( [ ' 77025 ' , ' 77401 ' ] , self . get_names ( qs ) )
# If we add a little more distance 77002 should be included.
qs = SouthTexasZipcode . objects . exclude ( name = ' 77005 ' ) . filter ( poly__distance_lte = ( z . poly , D ( m = 300 ) ) )
self . assertEqual ( [ ' 77002 ' , ' 77025 ' , ' 77401 ' ] , self . get_names ( qs ) )
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def test_geodetic_distance_lookups ( self ) :
"""
Test distance lookups on geodetic coordinate systems .
"""
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# Line is from Canberra to Sydney. Query is for all other cities within
# a 100km of that line (which should exclude only Hobart & Adelaide).
line = GEOSGeometry ( ' LINESTRING(144.9630 -37.8143,151.2607 -33.8870) ' , 4326 )
dist_qs = AustraliaCity . objects . filter ( point__distance_lte = ( line , D ( km = 100 ) ) )
if oracle or connection . ops . geography :
# Oracle and PostGIS 1.5 can do distance lookups on arbitrary geometries.
self . assertEqual ( 9 , dist_qs . count ( ) )
self . assertEqual ( [ ' Batemans Bay ' , ' Canberra ' , ' Hillsdale ' ,
' Melbourne ' , ' Mittagong ' , ' Shellharbour ' ,
' Sydney ' , ' Thirroul ' , ' Wollongong ' ] ,
self . get_names ( dist_qs ) )
else :
# PostGIS 1.4 and below only allows geodetic distance queries (utilizing
# ST_Distance_Sphere/ST_Distance_Spheroid) from Points to PointFields
# on geometry columns.
self . assertRaises ( ValueError , dist_qs . count )
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# Ensured that a ValueError was raised, none of the rest of the test is
# support on this backend, so bail now.
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if spatialite :
return
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# Too many params (4 in this case) should raise a ValueError.
self . assertRaises ( ValueError , len ,
AustraliaCity . objects . filter ( point__distance_lte = ( ' POINT(5 23) ' , D ( km = 100 ) , ' spheroid ' , ' 4 ' ) ) )
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# Not enough params should raise a ValueError.
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self . assertRaises ( ValueError , len ,
AustraliaCity . objects . filter ( point__distance_lte = ( ' POINT(5 23) ' , ) ) )
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# Getting all cities w/in 550 miles of Hobart.
hobart = AustraliaCity . objects . get ( name = ' Hobart ' )
qs = AustraliaCity . objects . exclude ( name = ' Hobart ' ) . filter ( point__distance_lte = ( hobart . point , D ( mi = 550 ) ) )
cities = self . get_names ( qs )
self . assertEqual ( cities , [ ' Batemans Bay ' , ' Canberra ' , ' Melbourne ' ] )
# Cities that are either really close or really far from Wollongong --
# and using different units of distance.
wollongong = AustraliaCity . objects . get ( name = ' Wollongong ' )
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d1 , d2 = D ( yd = 19500 ) , D ( nm = 400 ) # Yards (~17km) & Nautical miles.
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# Normal geodetic distance lookup (uses `distance_sphere` on PostGIS.
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gq1 = Q ( point__distance_lte = ( wollongong . point , d1 ) )
gq2 = Q ( point__distance_gte = ( wollongong . point , d2 ) )
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qs1 = AustraliaCity . objects . exclude ( name = ' Wollongong ' ) . filter ( gq1 | gq2 )
# Geodetic distance lookup but telling GeoDjango to use `distance_spheroid`
# instead (we should get the same results b/c accuracy variance won't matter
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# in this test case).
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if postgis :
gq3 = Q ( point__distance_lte = ( wollongong . point , d1 , ' spheroid ' ) )
gq4 = Q ( point__distance_gte = ( wollongong . point , d2 , ' spheroid ' ) )
qs2 = AustraliaCity . objects . exclude ( name = ' Wollongong ' ) . filter ( gq3 | gq4 )
querysets = [ qs1 , qs2 ]
else :
querysets = [ qs1 ]
for qs in querysets :
cities = self . get_names ( qs )
self . assertEqual ( cities , [ ' Adelaide ' , ' Hobart ' , ' Shellharbour ' , ' Thirroul ' ] )
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def test_area ( self ) :
"""
Test the ` area ` GeoQuerySet method .
"""
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# Reference queries:
# SELECT ST_Area(poly) FROM distapp_southtexaszipcode;
area_sq_m = [ 5437908.90234375 , 10183031.4389648 , 11254471.0073242 , 9881708.91772461 ]
# Tolerance has to be lower for Oracle and differences
# with GEOS 3.0.0RC4
tol = 2
for i , z in enumerate ( SouthTexasZipcode . objects . area ( ) ) :
self . assertAlmostEqual ( area_sq_m [ i ] , z . area . sq_m , tol )
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def test_length ( self ) :
"""
Test the ` length ` GeoQuerySet method .
"""
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# Reference query (should use `length_spheroid`).
# SELECT ST_length_spheroid(ST_GeomFromText('<wkt>', 4326) 'SPHEROID["WGS 84",6378137,298.257223563, AUTHORITY["EPSG","7030"]]');
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len_m1 = 473504.769553813
len_m2 = 4617.668
if spatialite :
# Does not support geodetic coordinate systems.
self . assertRaises ( ValueError , Interstate . objects . length )
else :
qs = Interstate . objects . length ( )
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tol = 2 if oracle else 3
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self . assertAlmostEqual ( len_m1 , qs [ 0 ] . length . m , tol )
# Now doing length on a projected coordinate system.
i10 = SouthTexasInterstate . objects . length ( ) . get ( name = ' I-10 ' )
self . assertAlmostEqual ( len_m2 , i10 . length . m , 2 )
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@no_spatialite
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def test_perimeter ( self ) :
"""
Test the ` perimeter ` GeoQuerySet method .
"""
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# Reference query:
# SELECT ST_Perimeter(distapp_southtexaszipcode.poly) FROM distapp_southtexaszipcode;
perim_m = [ 18404.3550889361 , 15627.2108551001 , 20632.5588368978 , 17094.5996143697 ]
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tol = 2 if oracle else 7
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for i , z in enumerate ( SouthTexasZipcode . objects . perimeter ( ) ) :
self . assertAlmostEqual ( perim_m [ i ] , z . perimeter . m , tol )
# Running on points; should return 0.
for i , c in enumerate ( SouthTexasCity . objects . perimeter ( model_att = ' perim ' ) ) :
self . assertEqual ( 0 , c . perim . m )
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def test_measurement_null_fields ( self ) :
"""
Test the measurement GeoQuerySet methods on fields with NULL values .
"""
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# Creating SouthTexasZipcode w/NULL value.
SouthTexasZipcode . objects . create ( name = ' 78212 ' )
# Performing distance/area queries against the NULL PolygonField,
# and ensuring the result of the operations is None.
htown = SouthTexasCity . objects . get ( name = ' Downtown Houston ' )
z = SouthTexasZipcode . objects . distance ( htown . point ) . area ( ) . get ( name = ' 78212 ' )
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self . assertIsNone ( z . distance )
self . assertIsNone ( z . area )