{"title":"Ranganna Teagaisc GeodJango","version":"6.0","locale":"ga","docname":"ref/contrib/gis/tutorial","url":"/ga/6.0/ref/contrib/gis/tutorial/","canonical":"https://djangodocs.dev/ga/6.0/ref/contrib/gis/tutorial/","summary":"Is modúl contrib san áireamh é GeodJango do Django a iompaíonn é ina creat gréasáin geografach den scoth.","html":"

Ranganna Teagaisc GeodJangoLink to this heading#

\n
\n

RéamhráLink to this heading#

\n

Is modúl contrib san áireamh é GeodJango do Django a iompaíonn é ina creat gréasáin geografach den scoth. Déanann GeodJango iarracht é a dhéanamh chomh simplí agus is féidir feidhmchláir gréasáin geografacha a chruthú, cosúil le seirbhísí suíomh-bhunaithe. I measc a ghnéithe tá:

\n\n

Glacann an rang teagaisc seo le eolas ar Django; dá bhrí sin, má tá tú nua-aimseartha do Django, léigh trí:doc: `rang teagaisc rialta' le do thoil chun eolas a chur ar Django ar dtús. </intro/tutorial01>

\n\n

Tabharfaidh an rang teagaisc seo treoir duit trí fheidhmchlár gréasáin geografach a chruthú chun féachaint ar na teorainneacha domhain. [#] _ Tógtar cuid den chód a úsáidtear sa rang teagaisc seo ó thionscadal GeoDjango bunaipeanna `_ agus/nó spreagtha ag an tionscadal `GeoDjango bunús.

\n\n
\n
\n

Ag bhunúLink to this heading#

\n
\n

Cruthaigh Bunachar Sonraí SpásúilLink to this heading#

\n

De ghnáth ní theastaíonn socrú speisialta, ionas gur féidir leat bunachar sonraí a chruthú mar a dhéanfá d'aon tionscadal eile. Soláthraímid roinnt leideanna do bhunachar sonraí roghnai

\n\n
\n
\n

Cruthaigh Tionscadal NuaLink to this heading#

\n

Úsáid an script caighdeánach django-admin ``chun tionscadal ar a dtugtar ``geodjango a chruthú:

\n

Linux / macOS

Shell
$ django-admin startproject geodjango\n
\n

Windows

Windows
...\\> django-admin startproject geodjango\n
\n

Cuirfidh sé seo tionscadal nua a thosú. Anois, cruthaigh feidhmchlár domh Django laistigh den tionscadal geodjango:

\n

Linux / macOS

Shell
$ cd geodjango\n$ python manage.py startapp world\n
\n

Windows

Windows
...\\> cd geodjango\n...\\> py manage.py startapp world\n
\n
\n
\n

Cumraigh settings.pyLink to this heading#

\n

Stóráiltear na socruithe tionscadail geodjango sa chomhad geodjango/settings.py. Cuir na socruithe nasc bunachar sonraí in eagar chun do shocrú a mheaitseáil:

\n
Code
DATABASES = {\n    "default": {\n        "ENGINE": "django.contrib.gis.db.backends.postgis",\n        "NAME": "geodjango",\n        "USER": "geo",\n    },\n}\n
\n

Ina theannta sin, modhnaigh an socrú:setting: INSTALLED_APPS chun go n-áirítear: mod: django.contrib.admin, :mod: django.contrib.gis, agus world (d'iarratas nua-chruthaithe):

\n
Code
INSTALLED_APPS = [\n    "django.contrib.admin",\n    "django.contrib.auth",\n    "django.contrib.contenttypes",\n    "django.contrib.sessions",\n    "django.contrib.messages",\n    "django.contrib.staticfiles",\n    "django.contrib.gis",\n    "world",\n]\n
\n
\n
\n
\n

Sonraí GeografachaLink to this heading#

\n
\n

Teorainneacha DomhandaLink to this heading#

\n

The world borders data is available in this zip file. Create a data\ndirectory in the world application, download the world borders data, and\nunzip. On GNU/Linux platforms, use the following commands:

\n

Linux / macOS

Shell
$ mkdir world/data\n$ cd world/data\n$ wget https://web.archive.org/web/20231220150759/https://thematicmapping.org/downloads/TM_WORLD_BORDERS-0.3.zip\n$ unzip TM_WORLD_BORDERS-0.3.zip\n$ cd ../..\n
\n

Windows

Windows
...\\> mkdir world\\data\n...\\> cd world\\data\n...\\> wget https://web.archive.org/web/20231220150759/https://thematicmapping.org/downloads/TM_WORLD_BORDERS-0.3.zip\n...\\> unzip TM_WORLD_BORDERS-0.3.zip\n...\\> cd ..\\..\n
\n

The world borders ZIP file contains a set of data files collectively known as\nan ESRI Shapefile, one of the most popular geospatial data formats. When\nunzipped, the world borders dataset includes files with the following\nextensions:

\n\n
\n
\n

Úsáid ogrinfo chun sonraí spásúla a scrúdúLink to this heading#

\n

Ligeann fóntais GDAL ``ogrinfo` a scrúdú ar mheiteashonraí comhaid cruth nó foinsí sonraí veicteora eile:

\n

Linux / macOS

Shell
$ ogrinfo world/data/TM_WORLD_BORDERS-0.3.shp\nINFO: Open of `world/data/TM_WORLD_BORDERS-0.3.shp'\n      using driver `ESRI Shapefile' successful.\n1: TM_WORLD_BORDERS-0.3 (Polygon)\n
\n

Windows

Windows
...\\> ogrinfo world\\data\\TM_WORLD_BORDERS-0.3.shp\nINFO: Open of `world/data/TM_WORLD_BORDERS-0.3.shp'\n      using driver `ESRI Shapefile' successful.\n1: TM_WORLD_BORDERS-0.3 (Polygon)\n
\n

ogrinfo tells us that the shapefile has one layer, and that this\nlayer contains polygon data. To find out more, we'll specify the layer name\nand use the -so option to get only the important summary information:

\n

Linux / macOS

Shell
$ ogrinfo -so world/data/TM_WORLD_BORDERS-0.3.shp TM_WORLD_BORDERS-0.3\nINFO: Open of `world/data/TM_WORLD_BORDERS-0.3.shp'\n      using driver `ESRI Shapefile' successful.\n\nLayer name: TM_WORLD_BORDERS-0.3\nMetadata:\n  DBF_DATE_LAST_UPDATE=2008-07-30\nGeometry: Polygon\nFeature Count: 246\nExtent: (-180.000000, -90.000000) - (180.000000, 83.623596)\nLayer SRS WKT:\nGEOGCRS["WGS 84",\n    DATUM["World Geodetic System 1984",\n        ELLIPSOID["WGS 84",6378137,298.257223563,\n            LENGTHUNIT["metre",1]]],\n    PRIMEM["Greenwich",0,\n        ANGLEUNIT["degree",0.0174532925199433]],\n    CS[ellipsoidal,2],\n        AXIS["latitude",north,\n            ORDER[1],\n            ANGLEUNIT["degree",0.0174532925199433]],\n        AXIS["longitude",east,\n            ORDER[2],\n            ANGLEUNIT["degree",0.0174532925199433]],\n    ID["EPSG",4326]]\nData axis to CRS axis mapping: 2,1\nFIPS: String (2.0)\nISO2: String (2.0)\nISO3: String (3.0)\nUN: Integer (3.0)\nNAME: String (50.0)\nAREA: Integer (7.0)\nPOP2005: Integer64 (10.0)\nREGION: Integer (3.0)\nSUBREGION: Integer (3.0)\nLON: Real (8.3)\nLAT: Real (7.3)\n
\n

Windows

Windows
...\\> ogrinfo -so world\\data\\TM_WORLD_BORDERS-0.3.shp TM_WORLD_BORDERS-0.3\nINFO: Open of `world/data/TM_WORLD_BORDERS-0.3.shp'\n      using driver `ESRI Shapefile' successful.\n\nLayer name: TM_WORLD_BORDERS-0.3\nMetadata:\n  DBF_DATE_LAST_UPDATE=2008-07-30\nGeometry: Polygon\nFeature Count: 246\nExtent: (-180.000000, -90.000000) - (180.000000, 83.623596)\nLayer SRS WKT:\nGEOGCRS["WGS 84",\n    DATUM["World Geodetic System 1984",\n        ELLIPSOID["WGS 84",6378137,298.257223563,\n            LENGTHUNIT["metre",1]]],\n    PRIMEM["Greenwich",0,\n        ANGLEUNIT["degree",0.0174532925199433]],\n    CS[ellipsoidal,2],\n        AXIS["latitude",north,\n            ORDER[1],\n            ANGLEUNIT["degree",0.0174532925199433]],\n        AXIS["longitude",east,\n            ORDER[2],\n            ANGLEUNIT["degree",0.0174532925199433]],\n    ID["EPSG",4326]]\nData axis to CRS axis mapping: 2,1\nFIPS: String (2.0)\nISO2: String (2.0)\nISO3: String (3.0)\nUN: Integer (3.0)\nNAME: String (50.0)\nAREA: Integer (7.0)\nPOP2005: Integer64 (10.0)\nREGION: Integer (3.0)\nSUBREGION: Integer (3.0)\nLON: Real (8.3)\nLAT: Real (7.3)\n
\n

This detailed summary information tells us the number of features in the layer\n(246), the geographic bounds of the data, the spatial reference system\n("SRS WKT"), as well as type information for each attribute field. For example,\nFIPS: String (2.0) indicates that the FIPS character field has\na maximum length of 2. Similarly, LON: Real (8.3) is a floating-point\nfield that holds a maximum of 8 digits up to three decimal places.

\n
\n
\n
\n

Samhlacha GeografachaLink to this heading#

\n
\n

Samhail Geografach a shainiúLink to this heading#

\n

Anois go ndearna tú scrúdú ar do thacar sonraí ag baint úsáide as ``ogrinfo`, cruthaigh samhail GeodJango chun na sonraí seo a léiriú:

\n
Code
from django.contrib.gis.db import models\n\n\nclass WorldBorder(models.Model):\n    # Regular Django fields corresponding to the attributes in the\n    # world borders shapefile.\n    name = models.CharField(max_length=50)\n    area = models.IntegerField()\n    pop2005 = models.IntegerField("Population 2005")\n    fips = models.CharField("FIPS Code", max_length=2, null=True)\n    iso2 = models.CharField("2 Digit ISO", max_length=2)\n    iso3 = models.CharField("3 Digit ISO", max_length=3)\n    un = models.IntegerField("United Nations Code")\n    region = models.IntegerField("Region Code")\n    subregion = models.IntegerField("Sub-Region Code")\n    lon = models.FloatField()\n    lat = models.FloatField()\n\n    # GeoDjango-specific: a geometry field (MultiPolygonField)\n    mpoly = models.MultiPolygonField()\n\n    # Returns the string representation of the model.\n    def __str__(self):\n        return self.name\n
\n

Tabhair faoi deara go n-allmhairítear an modúl samhlacha ``ó `django.contrib.gis.db.

\n

The default spatial reference system for geometry fields is WGS84 (meaning\nthe SRID is 4326) -- in other words, the field coordinates are in\nlongitude, latitude pairs in units of degrees. To use a different\ncoordinate system, set the SRID of the geometry field with the srid\nargument. Use an integer representing the coordinate system's EPSG code.

\n
\n
\n

Rith `imirceLink to this heading#

\n

Tar éis duit do mhúnla a shainiú, ní mór duit é a shioncronú leis an mbunachar sonraí. Ar dtús, cruthaigh imirce bunachar sonraí:

\n

Linux / macOS

Shell
$ python manage.py makemigrations\nMigrations for 'world':\n  world/migrations/0001_initial.py:\n    + Create model WorldBorder\n
\n

Windows

Windows
...\\> py manage.py makemigrations\nMigrations for 'world':\n  world/migrations/0001_initial.py:\n    + Create model WorldBorder\n
\n

Breathnaímid ar an SQL a ghinfidh an tábla don tsamhail ``Worldborder`:

\n

Linux / macOS

Shell
$ python manage.py sqlmigrate world 0001\n
\n

Windows

Windows
...\\> py manage.py sqlmigrate world 0001\n
\n

Ba chóir go dtáirgfeadh an t-ordú seo an t-aschur seo

\n
SQL
BEGIN;\n--\n-- Create model WorldBorder\n--\nCREATE TABLE "world_worldborder" (\n    "id" bigint NOT NULL PRIMARY KEY GENERATED BY DEFAULT AS IDENTITY,\n    "name" varchar(50) NOT NULL,\n    "area" integer NOT NULL,\n    "pop2005" integer NOT NULL,\n    "fips" varchar(2) NOT NULL,\n    "iso2" varchar(2) NOT NULL,\n    "iso3" varchar(3) NOT NULL,\n    "un" integer NOT NULL,\n    "region" integer NOT NULL,\n    "subregion" integer NOT NULL,\n    "lon" double precision NOT NULL,\n    "lat" double precision NOT NULL\n    "mpoly" geometry(MULTIPOLYGON,4326) NOT NULL\n)\n;\nCREATE INDEX "world_worldborder_mpoly_id" ON "world_worldborder" USING GIST ("mpoly");\nCOMMIT;\n
\n

Má tá cuma ceart air seo, rith: djadmin: migrate chun an tábla seo a chruthú sa bhunachar sonraí:

\n

Linux / macOS

Shell
$ python manage.py migrate\nOperations to perform:\n  Apply all migrations: admin, auth, contenttypes, sessions, world\nRunning migrations:\n  ...\n  Applying world.0001_initial... OK\n
\n

Windows

Windows
...\\> py manage.py migrate\nOperations to perform:\n  Apply all migrations: admin, auth, contenttypes, sessions, world\nRunning migrations:\n  ...\n  Applying world.0001_initial... OK\n
\n
\n
\n
\n

Sonraí Spásúla a IomLink to this heading#

\n

This section will show you how to import the world borders shapefile into the\ndatabase via GeoDjango models using the Fóntais allmhairithe sonraí Layermapping.

\n

Tá go leor bealaí éagsúla ann chun sonraí a iompórtáil isteach i mbunachar sonraí spásúil - seachas na huirlisí atá san áireamh laistigh de GeodJango, is féidir leat na rudaí seo a leanas a úsáid

\n\n
\n

Comhéadan GDALLink to this heading#

\n

Earlier, you used ogrinfo to examine the contents of the world borders\nshapefile. GeoDjango also includes a Pythonic interface to GDAL's powerful OGR\nlibrary that can work with all the vector data sources that OGR supports.

\n

Ar dtús, glaoch ar an bhlaosc Django:

\n

Linux / macOS

Shell
$ python manage.py shell\n
\n

Windows

Windows
...\\> py manage.py shell\n
\n

Má íoslódáil tú na sonraí:ref: worldborders níos luaithe sa rang teagaisc, ansin is féidir leat a chonair a chinneadh ag baint úsáide as Python's:class: pathlib.path:

\n
Python console
>>> from pathlib import Path\n>>> import world\n>>> world_shp = Path(world.__file__).resolve().parent / "data" / "TM_WORLD_BORDERS-0.3.shp"\n
\n

Anois, oscail an comhad cruth teorainneacha domhanda ag baint úsáide as comhéadan GeodjangoS:Class: ~django.contrib.gis.gdal.datasource:

\n
Python console
>>> from django.contrib.gis.gdal import DataSource\n>>> ds = DataSource(world_shp)\n>>> print(ds)\n/ ... /geodjango/world/data/TM_WORLD_BORDERS-0.3.shp (ESRI Shapefile)\n
\n

Is féidir le sraitheanna éagsúla de ghnéithe geospásúla a bheith ag rudaí foinse sonraí; áfach, ní cheadaítear ach sraith amháin a bheith ag comhaid chruthacha:

\n
Python console
>>> print(len(ds))\n1\n>>> lyr = ds[0]\n>>> print(lyr)\nTM_WORLD_BORDERS-0.3\n
\n

Is féidir leat cineál geoiméadrach an chiseal a fheiceáil agus cé mhéad gné atá ann:

\n
Python console
>>> print(lyr.geom_type)\nPolygon\n>>> print(len(lyr))\n246\n
\n\n

The Layer may also have a spatial reference\nsystem associated with it. If it does, the srs attribute will return a\nSpatialReference object:

\n
Python console
>>> srs = lyr.srs\n>>> print(srs)\nGEOGCS["WGS 84",\nDATUM["WGS_1984",\n    SPHEROID["WGS 84",6378137,298.257223563,\n        AUTHORITY["EPSG","7030"]],\n    AUTHORITY["EPSG","6326"]],\nPRIMEM["Greenwich",0,\n    AUTHORITY["EPSG","8901"]],\nUNIT["degree",0.0174532925199433,\n    AUTHORITY["EPSG","9122"]],\nAXIS["Latitude",NORTH],\nAXIS["Longitude",EAST],\nAUTHORITY["EPSG","4326"]]\n>>> srs.proj  # PROJ representation\n'+proj=longlat +datum=WGS84 +no_defs'\n
\n

Tá an comhad cruth seo sa chóras tagartha spásúil WGS84 a bhfuil tóir orthu - is é sin le rá, úsáideann na sonraí domhanfhad, péirí domhanleithead in aonaid céimeanna.

\n

In addition, shapefiles also support attribute fields that may contain\nadditional data. Here are the fields on the World Borders layer:

\n
Python console
>>> print(lyr.fields)\n['FIPS', 'ISO2', 'ISO3', 'UN', 'NAME', 'AREA', 'POP2005', 'REGION', 'SUBREGION', 'LON', 'LAT']\n
\n

Ligfidh an cód seo a leanas duit scrúdú a dhéanamh ar na cineálacha OGR (m.shláimhir nó sreang) a bhaineann le gach ceann de na réimsí:

\n
Python console
>>> [fld.__name__ for fld in lyr.field_types]\n['OFTString', 'OFTString', 'OFTString', 'OFTInteger', 'OFTString', 'OFTInteger', 'OFTInteger64', 'OFTInteger', 'OFTInteger', 'OFTReal', 'OFTReal']\n
\n

Is féidir leat athrá thar gach gné sa chiseal agus faisnéis a bhaint as geoiméadacht na gné (rochtain tríd an tréith geom) chomh maith le réimsí tréithe na ngné (a gcuirtear rochtain ar a luacha** trí mhodh ``get () ``):

\n
Python console
>>> for feat in lyr:\n...     print(feat.get("NAME"), feat.geom.num_points)\n...\nGuernsey 18\nJersey 26\nSouth Georgia South Sandwich Islands 338\nTaiwan 363\n
\n

Layer objects may be sliced:

\n
Python console
>>> lyr[0:2]\n[<django.contrib.gis.gdal.feature.Feature object at 0x2f47690>, <django.contrib.gis.gdal.feature.Feature object at 0x2f47650>]\n
\n

Agus is féidir gnéithe aonair a aisghabháil ag a n-ID gné:

\n
Python console
>>> feat = lyr[234]\n>>> print(feat.get("NAME"))\nSan Marino\n
\n

Féadfar geoiméadraí teorann a onnmhairiú mar WKT agus GeoJSON:

\n
Python console
>>> geom = feat.geom\n>>> print(geom.wkt)\nPOLYGON ((12.415798 43.957954,12.450554 ...\n>>> print(geom.json)\n{ "type": "Polygon", "coordinates": [ [ [ 12.415798, 43.957954 ], [ 12.450554, 43.979721 ], ...\n
\n
\n
\n

Sraith mapingLink to this heading#

\n

Chun na sonraí a iompórtáil, bain úsáid as LayerMapping i script Python. Cruthaigh comhad ar a dtugtar load.py taobh istigh den fheidhmchlár world, leis an gcód seo a leanas:

\n
Code
from pathlib import Path\nfrom django.contrib.gis.utils import LayerMapping\nfrom .models import WorldBorder\n\nworld_mapping = {\n    "fips": "FIPS",\n    "iso2": "ISO2",\n    "iso3": "ISO3",\n    "un": "UN",\n    "name": "NAME",\n    "area": "AREA",\n    "pop2005": "POP2005",\n    "region": "REGION",\n    "subregion": "SUBREGION",\n    "lon": "LON",\n    "lat": "LAT",\n    "mpoly": "MULTIPOLYGON",\n}\n\nworld_shp = Path(__file__).resolve().parent / "data" / "TM_WORLD_BORDERS-0.3.shp"\n\n\ndef run(verbose=True):\n    lm = LayerMapping(WorldBorder, world_shp, world_mapping, transform=False)\n    lm.save(strict=True, verbose=verbose)\n
\n

Cúpla nóta faoin méid atá ar siúl:

\n\n

Ina dhiaidh sin, glaoch ar an bhlaosc Django ón eolaire tionscadail geodjango:

\n

Linux / macOS

Shell
$ python manage.py shell\n
\n

Windows

Windows
...\\> py manage.py shell\n
\n

Ansin, iompórtáil an modúl load ``, glaoigh ar an ngnáthamh ``run, agus féach ar Layermapping ag déanamh an obair:

\n
Python console
>>> from world import load\n>>> load.run()\n
\n
\n
\n

Bain triail as ogrinspectLink to this heading#

\n

Now that you've seen how to define geographic models and import data with the\nFóntais allmhairithe sonraí Layermapping, it's possible to further automate this\nprocess with use of the ogrinspect management command. The\nogrinspect command introspects a GDAL-supported vector data source\n(e.g., a shapefile) and generates a model definition and LayerMapping\ndictionary automatically.

\n

Tá úsáid ghinearálta an ordaithe mar seo a leanas:

\n

Linux / macOS

Shell
$ python manage.py ogrinspect [options] <data_source> <model_name> [options]\n
\n

Windows

Windows
...\\> py manage.py ogrinspect [options] <data_source> <model_name> [options]\n
\n

data_source is the path to the GDAL-supported data source and\nmodel_name is the name to use for the model. Command-line options may\nbe used to further define how the model is generated.

\n

Mar shampla, atháirgeann an t-ordú seo a leanas beagnach an tsamhail Worldborder agus an foclóir mapála a cruthaíodh thuas, go huathoibríoch:

\n

Linux / macOS

Shell
$ python manage.py ogrinspect world/data/TM_WORLD_BORDERS-0.3.shp WorldBorder \\\n    --srid=4326 --mapping --multi\n
\n

Windows

Windows
...\\> py manage.py ogrinspect world\\data\\TM_WORLD_BORDERS-0.3.shp WorldBorder \\\n    --srid=4326 --mapping --multi\n
\n

Cúpla nóta faoi na roghanna líne ordaithe a thugtar thuas:

\n\n

Táirgeann an t-ordú an t-aschur seo a leanas, ar féidir a chóipeáil go díreach isteach sa models.py` d'fheidhmchlár GeoDjango:

\n
Code
# This is an auto-generated Django model module created by ogrinspect.\nfrom django.contrib.gis.db import models\n\n\nclass WorldBorder(models.Model):\n    fips = models.CharField(max_length=2)\n    iso2 = models.CharField(max_length=2)\n    iso3 = models.CharField(max_length=3)\n    un = models.IntegerField()\n    name = models.CharField(max_length=50)\n    area = models.IntegerField()\n    pop2005 = models.IntegerField()\n    region = models.IntegerField()\n    subregion = models.IntegerField()\n    lon = models.FloatField()\n    lat = models.FloatField()\n    geom = models.MultiPolygonField(srid=4326)\n\n\n# Auto-generated `LayerMapping` dictionary for WorldBorder model\nworldborders_mapping = {\n    "fips": "FIPS",\n    "iso2": "ISO2",\n    "iso3": "ISO3",\n    "un": "UN",\n    "name": "NAME",\n    "area": "AREA",\n    "pop2005": "POP2005",\n    "region": "REGION",\n    "subregion": "SUBREGION",\n    "lon": "LON",\n    "lat": "LAT",\n    "geom": "MULTIPOLYGON",\n}\n
\n
\n
\n
\n

Ceisteanna SpásúlaLink to this heading#

\n
\n

Cuardaigh SpásúlaLink to this heading#

\n

GeoDjango adds spatial lookups to the Django ORM. For example, you\ncan find the country in the WorldBorder table that contains\na particular point. First, fire up the management shell:

\n

Linux / macOS

Shell
$ python manage.py shell\n
\n

Windows

Windows
...\\> py manage.py shell\n
\n

Anois, sainmhínigh pointe spéise [#] _:

\n
Python console
>>> pnt_wkt = "POINT(-95.3385 29.7245)"\n
\n

The pnt_wkt string represents the point at -95.3385 degrees longitude,\n29.7245 degrees latitude. The geometry is in a format known as\nWell Known Text (WKT), a standard issued by the Open Geospatial\nConsortium (OGC). [4] Import the WorldBorder model, and perform\na contains lookup using the pnt_wkt as the parameter:

\n
Python console
>>> from world.models import WorldBorder\n>>> WorldBorder.objects.filter(mpoly__contains=pnt_wkt)\n<QuerySet [<WorldBorder: United States>]>\n
\n

Anseo, ghnóthaigh tú ``QuerySet ``gan ach samhail amháin: teorainn na Stát Aontaithe (go díreach cad a bheadh ag súil leat).

\n

Similarly, you may also use a GEOS geometry object. Here, you can combine the intersects spatial\nlookup with the get method to retrieve only the WorldBorder instance\nfor San Marino instead of a queryset:

\n
Python console
>>> from django.contrib.gis.geos import Point\n>>> pnt = Point(12.4604, 43.9420)\n>>> WorldBorder.objects.get(mpoly__intersects=pnt)\n<WorldBorder: San Marino>\n
\n

The contains and intersects lookups are just a subset of the available\nqueries -- the API Bunachar Sonraí GeodJango documentation has more.

\n
\n
\n

Claochluithe SpásúlaLink to this heading#

\n

When doing spatial queries, GeoDjango automatically transforms\ngeometries if they're in a different coordinate system. In the following\nexample, coordinates will be expressed in EPSG SRID 32140,\na coordinate system specific to south Texas only and in units of\nmeters, not degrees:

\n
Python console
>>> from django.contrib.gis.geos import GEOSGeometry, Point\n>>> pnt = Point(954158.1, 4215137.1, srid=32140)\n
\n

Tabhair faoi deara gur féidir “pnt” a thógáil le EWKT freisin, foirm “leathnaithe” de WKT a chuimsíonn an SRID:

\n
Python console
>>> pnt = GEOSGeometry("SRID=32140;POINT(954158.1 4215137.1)")\n
\n

Fillfidh ORM GeodJango luachanna geoiméadrachta go huathoibríoch i SQL claochlú, rud a ligeann don fhorbróir oibriú ag leibhéal níos airde teastartha:

\n
Python console
>>> qs = WorldBorder.objects.filter(mpoly__intersects=pnt)\n>>> print(qs.query)  # Generating the SQL\nSELECT "world_worldborder"."id", "world_worldborder"."name", "world_worldborder"."area",\n"world_worldborder"."pop2005", "world_worldborder"."fips", "world_worldborder"."iso2",\n"world_worldborder"."iso3", "world_worldborder"."un", "world_worldborder"."region",\n"world_worldborder"."subregion", "world_worldborder"."lon", "world_worldborder"."lat",\n"world_worldborder"."mpoly" FROM "world_worldborder"\nWHERE ST_Intersects("world_worldborder"."mpoly", ST_Transform(%s, 4326))\n>>> qs  # printing evaluates the queryset\n<QuerySet [<WorldBorder: United States>]>\n
\n\n
\n
\n

Geoiméadraí leisciúlaLink to this heading#

\n

GeoDjango loads geometries in a standardized textual representation. When the\ngeometry field is first accessed, GeoDjango creates a\nGEOSGeometry object, exposing powerful\nfunctionality, such as serialization properties for popular geospatial\nformats:

\n
Python console
>>> sm = WorldBorder.objects.get(name="San Marino")\n>>> sm.mpoly\n<MultiPolygon object at 0x24c6798>\n>>> sm.mpoly.wkt  # WKT\nMULTIPOLYGON (((12.4157980000000006 43.9579540000000009, 12.4505540000000003 43.9797209999999978, ...\n>>> sm.mpoly.wkb  # WKB (as Python binary buffer)\n<read-only buffer for 0x1fe2c70, size -1, offset 0 at 0x2564c40>\n>>> sm.mpoly.geojson  # GeoJSON\n'{ "type": "MultiPolygon", "coordinates": [ [ [ [ 12.415798, 43.957954 ], [ 12.450554, 43.979721 ], ...\n
\n

Áirítear leis seo rochtain ar na hardoibríochtaí geoiméadracha go léir a sholáthraíonn leabharlann GEOS:

\n
Python console
>>> pnt = Point(12.4604, 43.9420)\n>>> sm.mpoly.contains(pnt)\nTrue\n>>> pnt.contains(sm.mpoly)\nFalse\n
\n
\n
\n

Anótaí geografachaLink to this heading#

\n

GeoDjango also offers a set of geographic annotations to compute distances and\nseveral other operations (intersection, difference, etc.). See the\nFeidhmeanna Bunachar Sonraí documentation.

\n
\n
\n
\n

Cuir do chuid sonraí ar an léarscáilLink to this heading#

\n
\n

Riarachán GeografachLink to this heading#

\n

Django's admin application supports editing\ngeometry fields.

\n
\n

BuneilimintíLink to this heading#

\n

Ligeann riarachán Django d'úsáideoirí geoiméadraí a chruthú agus a mhodhnú ar léarscáil slippy JavaScript (faoi thiomáint ag OpenLayers).

\n

Déanaimis tumadóireacht isteach. Cruthaigh comhad darb ainm admin.py` taobh istigh den fheidhmchlár domh leis an gcód seo a leanas:

\n
Code
from django.contrib.gis import admin\nfrom .models import WorldBorder\n\nadmin.site.register(WorldBorder, admin.ModelAdmin)\n
\n

Ansin, cuir do urls.py` in eagar san fhillteán feidhmchláir geodjango mar seo a leanas:

\n
Code
from django.contrib import admin\nfrom django.urls import include, path\n\nurlpatterns = [\n    path("admin/", admin.site.urls),\n]\n
\n

Cruthaigh úsáideoir riaracháin:

\n

Linux / macOS

Shell
$ python manage.py createsuperuser\n
\n

Windows

Windows
...\\> py manage.py createsuperuser\n
\n

Ansin, cuir tús leis an bhfreastalaí forbartha Django:

\n

Linux / macOS

Shell
$ python manage.py runserver\n
\n

Windows

Windows
...\\> py manage.py runserver\n
\n

Faoi dheireadh, brabhsáil chuig http://localhost:8000/admin/, agus logáil isteach leis an úsáideoir a chruthaigh tú díreach. Brabhsáil chuig aon cheann de na hiontrálacha Worldborder - is féidir na teorainneacha a chur in eagar trí chliceáil ar pholugún agus na coirteanna a tharraingt go dtí an suíomh atá ag teastáil.

\n
\n
\n

GisModelAdminLink to this heading#

\n

Leis an: class: ~django.contrib.gis.admin.gismodelAdmin, úsáideann GeoDjango ciseal OpenStreetMap sa riarachán. Soláthraíonn sé seo níos mó comhthéacs (lena n-áirítear sonraí sráide agus smachta) ná mar atá ar fáil len:class: ~django.contrib.admin.modelAdmin (a úsáideann an tacar sonraí Level Léarscáil Vector 0 WMS atá óstáilte ag OsGeo).

\n

Caithfear na comhaid aistrithe dáta PROJ a shuiteáil (féach an:ref: `Treoracha suiteála PROJ <proj4>`le haghaidh tuilleadh sonraí).

\n

Má chomhlíonann tú an riachtanas seo, ansin bain úsáid as an rang rogha GisModelAdmin i do chomhad admin.py:

\n
Code
admin.site.register(WorldBorder, admin.GISModelAdmin)\n
\n

Fonótaí

\n\n
\n
\n
","rootId":"geodjango-tutorial","toc":[{"title":"Réamhrá","anchor":"introduction","children":[]},{"title":"Ag bhunú","anchor":"setting-up","children":[{"title":"Cruthaigh Bunachar Sonraí Spásúil","anchor":"create-a-spatial-database","children":[]},{"title":"Cruthaigh Tionscadal Nua","anchor":"create-a-new-project","children":[]},{"title":"Cumraigh settings.py","anchor":"configure-settings-py","children":[]}]},{"title":"Sonraí Geografacha","anchor":"geographic-data","children":[{"title":"Teorainneacha Domhanda","anchor":"worldborders","children":[]},{"title":"Úsáid ogrinfo chun sonraí spásúla a scrúdú","anchor":"use-ogrinfo-to-examine-spatial-data","children":[]}]},{"title":"Samhlacha Geografacha","anchor":"geographic-models","children":[{"title":"Samhail Geografach a shainiú","anchor":"defining-a-geographic-model","children":[]},{"title":"Rith `imirce","anchor":"run-migrate","children":[]}]},{"title":"Sonraí Spásúla a Iom","anchor":"importing-spatial-data","children":[{"title":"Comhéadan GDAL","anchor":"gdal-interface","children":[]},{"title":"Sraith maping","anchor":"layermapping","children":[]},{"title":"Bain triail as ogrinspect","anchor":"try-ogrinspect","children":[]}]},{"title":"Ceisteanna Spásúla","anchor":"spatial-queries","children":[{"title":"Cuardaigh Spásúla","anchor":"spatial-lookups","children":[]},{"title":"Claochluithe Spásúla","anchor":"automatic-spatial-transformations","children":[]},{"title":"Geoiméadraí leisciúla","anchor":"lazy-geometries","children":[]},{"title":"Anótaí geografacha","anchor":"geographic-annotations","children":[]}]},{"title":"Cuir do chuid sonraí ar an léarscáil","anchor":"putting-your-data-on-the-map","children":[{"title":"Riarachán Geografach","anchor":"geographic-admin","children":[{"title":"Buneilimintí","anchor":"basics","children":[]},{"title":"GisModelAdmin","anchor":"gismodeladmin","children":[]}]}]}],"breadcrumbs":[{"docname":"ref/index","title":"Tagairt API","url":"/ga/6.0/ref/"},{"docname":"ref/contrib/index","title":"Pacáistí contrib","url":"/ga/6.0/ref/contrib/"},{"docname":"ref/contrib/gis/index","title":"GeodJango","url":"/ga/6.0/ref/contrib/gis/"}],"prev":{"docname":"ref/contrib/gis/index","title":"GeodJango","url":"/ga/6.0/ref/contrib/gis/"},"next":{"docname":"ref/contrib/gis/install/index","title":"Suiteáil GeodJango","url":"/ga/6.0/ref/contrib/gis/install/"},"formats":{"html":"/ga/6.0/ref/contrib/gis/tutorial/","markdown":"/ga/6.0/ref/contrib/gis/tutorial.md","json":"/ga/6.0/ref/contrib/gis/tutorial.json"},"source":"https://github.com/django/django/blob/stable/6.0.x/docs/ref/contrib/gis/tutorial.txt","official":"https://docs.djangoproject.com/ga/6.0/ref/contrib/gis/tutorial/","inVersions":["6.1","6.0","5.2"],"inLocales":["en","sv","zh-hans","ga","fr","ja","id","it","pt-br","ko","es","el","pl"]}