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Fixed #36097 -- Replaced GIS functions table with section headers for better readability and navigation.

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@ -20,23 +20,11 @@ function to see if your database backend supports the function you want to use.
If you call a geographic function on a backend that doesn't support it, you'll If you call a geographic function on a backend that doesn't support it, you'll
get a ``NotImplementedError`` exception. get a ``NotImplementedError`` exception.
Function's summary: Measurements
============
========================= ======================== ====================== ======================= ================== ================== ======================
Measurement Relationships Operations Editors Input format Output format Miscellaneous
========================= ======================== ====================== ======================= ================== ================== ======================
:class:`Area` :class:`Azimuth` :class:`Difference` :class:`ForcePolygonCW` :class:`AsGeoJSON` :class:`IsEmpty`
:class:`Distance` :class:`BoundingCircle` :class:`Intersection` :class:`MakeValid` :class:`AsGML` :class:`IsValid`
:class:`GeometryDistance` :class:`Centroid` :class:`SymDifference` :class:`Reverse` :class:`AsKML` :class:`MemSize`
:class:`Length` :class:`ClosestPoint` :class:`Union` :class:`Rotate` :class:`AsSVG` :class:`NumGeometries`
:class:`Perimeter` :class:`Envelope` :class:`Scale` :class:`FromWKB` :class:`AsWKB` :class:`NumPoints`
:class:`LineLocatePoint` :class:`SnapToGrid` :class:`FromWKT` :class:`AsWKT`
:class:`PointOnSurface` :class:`Transform` :class:`GeoHash`
:class:`Translate`
========================= ======================== ====================== ======================= ================== ================== ======================
``Area`` ``Area``
======== --------
.. class:: Area(expression, **extra) .. class:: Area(expression, **extra)
@ -50,233 +38,8 @@ field as an :class:`~django.contrib.gis.measure.Area` measure.
MySQL and SpatiaLite without LWGEOM/RTTOPO don't support area calculations on MySQL and SpatiaLite without LWGEOM/RTTOPO don't support area calculations on
geographic SRSes. geographic SRSes.
``AsGeoJSON``
=============
.. class:: AsGeoJSON(expression, bbox=False, crs=False, precision=8, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-geojson-functions.html#function_st-asgeojson>`__,
Oracle, `PostGIS <https://postgis.net/docs/ST_AsGeoJSON.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `GeoJSON
<https://geojson.org/>`_ representation of the geometry. Note that the result
is not a complete GeoJSON structure but only the ``geometry`` key content of a
GeoJSON structure. See also :doc:`/ref/contrib/gis/serializers`.
Example:
.. code-block:: pycon
>>> City.objects.annotate(json=AsGeoJSON("point")).get(name="Chicago").json
{"type":"Point","coordinates":[-87.65018,41.85039]}
===================== =====================================================
Keyword Argument Description
===================== =====================================================
``bbox`` Set this to ``True`` if you want the bounding box
to be included in the returned GeoJSON. Ignored on
Oracle.
``crs`` Set this to ``True`` if you want the coordinate
reference system to be included in the returned
GeoJSON. Ignored on MySQL and Oracle.
``precision`` It may be used to specify the number of significant
digits for the coordinates in the GeoJSON
representation -- the default value is 8. Ignored on
Oracle.
===================== =====================================================
``AsGML``
=========
.. class:: AsGML(expression, version=2, precision=8, **extra)
*Availability*: Oracle, `PostGIS <https://postgis.net/docs/ST_AsGML.html>`__,
SpatiaLite
Accepts a single geographic field or expression and returns a `Geographic Markup
Language (GML)`__ representation of the geometry.
Example:
.. code-block:: pycon
>>> qs = Zipcode.objects.annotate(gml=AsGML("poly"))
>>> print(qs[0].gml)
<gml:Polygon srsName="EPSG:4326"><gml:OuterBoundaryIs>-147.78711,70.245363 ...
-147.78711,70.245363</gml:OuterBoundaryIs></gml:Polygon>
===================== =====================================================
Keyword Argument Description
===================== =====================================================
``precision`` Specifies the number of significant digits for the
coordinates in the GML representation -- the default
value is 8. Ignored on Oracle.
``version`` Specifies the GML version to use: 2 (default) or 3.
===================== =====================================================
__ https://en.wikipedia.org/wiki/Geography_Markup_Language
``AsKML``
=========
.. class:: AsKML(expression, precision=8, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_AsKML.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `Keyhole Markup
Language (KML)`__ representation of the geometry.
Example:
.. code-block:: pycon
>>> qs = Zipcode.objects.annotate(kml=AsKML("poly"))
>>> print(qs[0].kml)
<Polygon><outerBoundaryIs><LinearRing><coordinates>-103.04135,36.217596,0 ...
-103.04135,36.217596,0</coordinates></LinearRing></outerBoundaryIs></Polygon>
===================== =====================================================
Keyword Argument Description
===================== =====================================================
``precision`` This keyword may be used to specify the number of
significant digits for the coordinates in the KML
representation -- the default value is 8.
===================== =====================================================
__ https://developers.google.com/kml/documentation/
``AsSVG``
=========
.. class:: AsSVG(expression, relative=False, precision=8, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_AsSVG.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `Scalable Vector
Graphics (SVG)`__ representation of the geometry.
===================== =====================================================
Keyword Argument Description
===================== =====================================================
``relative`` If set to ``True``, the path data will be implemented
in terms of relative moves. Defaults to ``False``,
meaning that absolute moves are used instead.
``precision`` This keyword may be used to specify the number of
significant digits for the coordinates in the SVG
representation -- the default value is 8.
===================== =====================================================
__ https://www.w3.org/Graphics/SVG/
``AsWKB``
=========
.. class:: AsWKB(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-format-conversion-functions.html#function_st-asbinary>`__,
Oracle, `PostGIS <https://postgis.net/docs/ST_AsBinary.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `Well-known
binary (WKB)`_ representation of the geometry.
Example:
.. code-block:: pycon
>>> bytes(City.objects.annotate(wkb=AsWKB("point")).get(name="Chelyabinsk").wkb)
b'\x01\x01\x00\x00\x00]3\xf9f\x9b\x91K@\x00X\x1d9\xd2\xb9N@'
``AsWKT``
=========
.. class:: AsWKT(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-format-conversion-functions.html#function_st-astext>`__,
Oracle, `PostGIS <https://postgis.net/docs/ST_AsText.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `Well-known text
(WKT)`_ representation of the geometry.
Example:
.. code-block:: pycon
>>> City.objects.annotate(wkt=AsWKT("point")).get(name="Chelyabinsk").wkt
'POINT (55.137555 61.451728)'
``Azimuth``
===========
.. class:: Azimuth(point_a, point_b, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_Azimuth.html>`__,
SpatiaLite (LWGEOM/RTTOPO)
Returns the azimuth in radians of the segment defined by the given point
geometries, or ``None`` if the two points are coincident. The azimuth is angle
referenced from north and is positive clockwise: north = ``0``; east = ``π/2``;
south = ``π``; west = ``3π/2``.
``BoundingCircle``
==================
.. class:: BoundingCircle(expression, num_seg=48, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_MinimumBoundingCircle.html>`__,
`Oracle <https://docs.oracle.com/en/database/oracle/oracle-database/21/spatl/
SDO_GEOM-reference.html#GUID-82A61626-BB64-4793-B53D-A0DBEC91831A>`_,
SpatiaLite 5.1+
Accepts a single geographic field or expression and returns the smallest circle
polygon that can fully contain the geometry.
The ``num_seg`` parameter is used only on PostGIS.
``Centroid``
============
.. class:: Centroid(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-polygon-property-functions.html#function_st-centroid>`__,
`PostGIS <https://postgis.net/docs/ST_Centroid.html>`__, Oracle, SpatiaLite
Accepts a single geographic field or expression and returns the ``centroid``
value of the geometry.
``ClosestPoint``
================
.. class:: ClosestPoint(expr1, expr2, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_ClosestPoint.html>`__,
SpatiaLite
Accepts two geographic fields or expressions and returns the 2-dimensional
point on geometry A that is closest to geometry B.
``Difference``
==============
.. class:: Difference(expr1, expr2, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-operator-functions.html#function_st-difference>`__,
`PostGIS <https://postgis.net/docs/ST_Difference.html>`__, Oracle, SpatiaLite
Accepts two geographic fields or expressions and returns the geometric
difference, that is the part of geometry A that does not intersect with
geometry B.
``Distance`` ``Distance``
============ ------------
.. class:: Distance(expr1, expr2, spheroid=None, **extra) .. class:: Distance(expr1, expr2, spheroid=None, **extra)
@ -324,79 +87,8 @@ queryset is calculated:
in kilometers. See :doc:`measure` for usage details and the list of in kilometers. See :doc:`measure` for usage details and the list of
:ref:`supported_units`. :ref:`supported_units`.
``Envelope``
============
.. class:: Envelope(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-general-property-functions.html#function_st-envelope>`__,
`Oracle <https://docs.oracle.com/en/database/oracle/oracle-database/21/spatl/
spatial-operators-reference.html#GUID-ACED800F-3435-44AA-9606-D40934A23ED0>`__,
`PostGIS <https://postgis.net/docs/ST_Envelope.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns the geometry
representing the bounding box of the geometry.
``ForcePolygonCW``
==================
.. class:: ForcePolygonCW(expression, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_ForcePolygonCW.html>`__,
SpatiaLite
Accepts a single geographic field or expression and returns a modified version
of the polygon/multipolygon in which all exterior rings are oriented clockwise
and all interior rings are oriented counterclockwise. Non-polygonal geometries
are returned unchanged.
``FromWKB``
===========
.. class:: FromWKB(expression, srid=0, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-wkb-functions.html#function_st-geomfromwkb>`__,
Oracle, `PostGIS <https://postgis.net/docs/ST_GeomFromWKB.html>`__, SpatiaLite
Creates geometry from `Well-known binary (WKB)`_ representation. The optional
``srid`` argument allows to specify the SRID of the resulting geometry.
``srid`` is ignored on Oracle.
``FromWKT``
===========
.. class:: FromWKT(expression, srid=0, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-wkt-functions.html#function_st-geomfromtext>`__,
Oracle, `PostGIS <https://postgis.net/docs/ST_GeomFromText.html>`__, SpatiaLite
Creates geometry from `Well-known text (WKT)`_ representation. The optional
``srid`` argument allows to specify the SRID of the resulting geometry.
``srid`` is ignored on Oracle.
``GeoHash``
===========
.. class:: GeoHash(expression, precision=None, **extra)
*Availability*: `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-geohash-functions.html#function_st-geohash>`__,
`PostGIS <https://postgis.net/docs/ST_GeoHash.html>`__, SpatiaLite
(LWGEOM/RTTOPO)
Accepts a single geographic field or expression and returns a `GeoHash`__
representation of the geometry.
The ``precision`` keyword argument controls the number of characters in the
result.
__ https://en.wikipedia.org/wiki/Geohash
``GeometryDistance`` ``GeometryDistance``
==================== --------------------
.. class:: GeometryDistance(expr1, expr2, **extra) .. class:: GeometryDistance(expr1, expr2, **extra)
@ -406,42 +98,8 @@ Accepts two geographic fields or expressions and returns the distance between
them. When used in an :meth:`~django.db.models.query.QuerySet.order_by` clause, them. When used in an :meth:`~django.db.models.query.QuerySet.order_by` clause,
it provides index-assisted nearest-neighbor result sets. it provides index-assisted nearest-neighbor result sets.
``Intersection``
================
.. class:: Intersection(expr1, expr2, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-operator-functions.html#function_st-intersection>`__,
`PostGIS <https://postgis.net/docs/ST_Intersection.html>`__, Oracle, SpatiaLite
Accepts two geographic fields or expressions and returns the geometric
intersection between them.
``IsEmpty``
===========
.. class:: IsEmpty(expr)
*Availability*: `PostGIS <https://postgis.net/docs/ST_IsEmpty.html>`__
Accepts a geographic field or expression and tests if the value is an empty
geometry. Returns ``True`` if its value is empty and ``False`` otherwise.
``IsValid``
===========
.. class:: IsValid(expr)
*Availability*: `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-convenience-functions.html#function_st-isvalid>`__,
`PostGIS <https://postgis.net/docs/ST_IsValid.html>`__, Oracle, SpatiaLite
Accepts a geographic field or expression and tests if the value is well formed.
Returns ``True`` if its value is a valid geometry and ``False`` otherwise.
``Length`` ``Length``
========== ----------
.. class:: Length(expression, spheroid=True, **extra) .. class:: Length(expression, spheroid=True, **extra)
@ -460,8 +118,87 @@ resource-intensive) with the ``spheroid`` keyword argument.
MySQL doesn't support length calculations on geographic SRSes. MySQL doesn't support length calculations on geographic SRSes.
``Perimeter``
-------------
.. class:: Perimeter(expression, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_Perimeter.html>`__,
Oracle, SpatiaLite
Accepts a single geographic field or expression and returns the perimeter of the
geometry field as a :class:`~django.contrib.gis.measure.Distance` object.
Relationships
=============
``Azimuth``
-----------
.. class:: Azimuth(point_a, point_b, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_Azimuth.html>`__,
SpatiaLite (LWGEOM/RTTOPO)
Returns the azimuth in radians of the segment defined by the given point
geometries, or ``None`` if the two points are coincident. The azimuth is angle
referenced from north and is positive clockwise: north = ``0``; east = ``π/2``;
south = ``π``; west = ``3π/2``.
``BoundingCircle``
------------------
.. class:: BoundingCircle(expression, num_seg=48, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_MinimumBoundingCircle.html>`__,
`Oracle <https://docs.oracle.com/en/database/oracle/oracle-database/21/spatl/
SDO_GEOM-reference.html#GUID-82A61626-BB64-4793-B53D-A0DBEC91831A>`_,
SpatiaLite 5.1+
Accepts a single geographic field or expression and returns the smallest circle
polygon that can fully contain the geometry.
The ``num_seg`` parameter is used only on PostGIS.
``Centroid``
------------
.. class:: Centroid(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-polygon-property-functions.html#function_st-centroid>`__,
`PostGIS <https://postgis.net/docs/ST_Centroid.html>`__, Oracle, SpatiaLite
Accepts a single geographic field or expression and returns the ``centroid``
value of the geometry.
``ClosestPoint``
----------------
.. class:: ClosestPoint(expr1, expr2, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_ClosestPoint.html>`__,
SpatiaLite
Accepts two geographic fields or expressions and returns the 2-dimensional
point on geometry A that is closest to geometry B.
``Envelope``
------------
.. class:: Envelope(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-general-property-functions.html#function_st-envelope>`__,
`Oracle <https://docs.oracle.com/en/database/oracle/oracle-database/21/spatl/
spatial-operators-reference.html#GUID-ACED800F-3435-44AA-9606-D40934A23ED0>`__,
`PostGIS <https://postgis.net/docs/ST_Envelope.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns the geometry
representing the bounding box of the geometry.
``LineLocatePoint`` ``LineLocatePoint``
=================== -------------------
.. class:: LineLocatePoint(linestring, point, **extra) .. class:: LineLocatePoint(linestring, point, **extra)
@ -471,8 +208,92 @@ SpatiaLite
Returns a float between 0 and 1 representing the location of the closest point on Returns a float between 0 and 1 representing the location of the closest point on
``linestring`` to the given ``point``, as a fraction of the 2D line length. ``linestring`` to the given ``point``, as a fraction of the 2D line length.
``PointOnSurface``
------------------
.. class:: PointOnSurface(expression, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_PointOnSurface.html>`__,
MariaDB, Oracle, SpatiaLite
Accepts a single geographic field or expression and returns a ``Point`` geometry
guaranteed to lie on the surface of the field; otherwise returns ``None``.
Operations
==========
``Difference``
--------------
.. class:: Difference(expr1, expr2, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-operator-functions.html#function_st-difference>`__,
`PostGIS <https://postgis.net/docs/ST_Difference.html>`__, Oracle, SpatiaLite
Accepts two geographic fields or expressions and returns the geometric
difference, that is the part of geometry A that does not intersect with
geometry B.
``Intersection``
----------------
.. class:: Intersection(expr1, expr2, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-operator-functions.html#function_st-intersection>`__,
`PostGIS <https://postgis.net/docs/ST_Intersection.html>`__, Oracle, SpatiaLite
Accepts two geographic fields or expressions and returns the geometric
intersection between them.
``SymDifference``
-----------------
.. class:: SymDifference(expr1, expr2, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-operator-functions.html#function_st-symdifference>`__,
`PostGIS <https://postgis.net/docs/ST_SymDifference.html>`__, Oracle,
SpatiaLite
Accepts two geographic fields or expressions and returns the geometric
symmetric difference (union without the intersection) between the given
parameters.
``Union``
---------
.. class:: Union(expr1, expr2, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-operator-functions.html#function_st-union>`__,
`PostGIS <https://postgis.net/docs/ST_Union.html>`__, Oracle, SpatiaLite
Accepts two geographic fields or expressions and returns the union of both
geometries.
.. _`Well-known binary (WKB)`: https://en.wikipedia.org/wiki/Well-known_text_representation_of_geometry#Well-known_binary
.. _`Well-known text (WKT)`: https://en.wikipedia.org/wiki/Well-known_text_representation_of_geometry
Editors
=======
``ForcePolygonCW``
------------------
.. class:: ForcePolygonCW(expression, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_ForcePolygonCW.html>`__,
SpatiaLite
Accepts a single geographic field or expression and returns a modified version
of the polygon/multipolygon in which all exterior rings are oriented clockwise
and all interior rings are oriented counterclockwise. Non-polygonal geometries
are returned unchanged.
``MakeValid`` ``MakeValid``
============= -------------
.. class:: MakeValid(expr) .. class:: MakeValid(expr)
@ -484,70 +305,8 @@ a valid geometry without losing any of the input vertices. Geometries that are
already valid are returned without changes. Simple polygons might become a already valid are returned without changes. Simple polygons might become a
multipolygon and the result might be of lower dimension than the input. multipolygon and the result might be of lower dimension than the input.
``MemSize``
===========
.. class:: MemSize(expression, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_MemSize.html>`__
Accepts a single geographic field or expression and returns the memory size
(number of bytes) that the geometry field takes.
``NumGeometries``
=================
.. class:: NumGeometries(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-geometrycollection-property-functions.html#function_st-numgeometries>`__,
`PostGIS <https://postgis.net/docs/ST_NumGeometries.html>`__, Oracle,
SpatiaLite
Accepts a single geographic field or expression and returns the number of
geometries if the geometry field is a collection (e.g., a ``GEOMETRYCOLLECTION``
or ``MULTI*`` field). Returns 1 for single geometries.
On MySQL, returns ``None`` for single geometries.
``NumPoints``
=============
.. class:: NumPoints(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-linestring-property-functions.html#function_st-numpoints>`__,
`PostGIS <https://postgis.net/docs/ST_NPoints.html>`__, Oracle, SpatiaLite
Accepts a single geographic field or expression and returns the number of points
in a geometry.
On MySQL, returns ``None`` for any non-``LINESTRING`` geometry.
``Perimeter``
=============
.. class:: Perimeter(expression, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_Perimeter.html>`__,
Oracle, SpatiaLite
Accepts a single geographic field or expression and returns the perimeter of the
geometry field as a :class:`~django.contrib.gis.measure.Distance` object.
``PointOnSurface``
==================
.. class:: PointOnSurface(expression, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_PointOnSurface.html>`__,
MariaDB, Oracle, SpatiaLite
Accepts a single geographic field or expression and returns a ``Point`` geometry
guaranteed to lie on the surface of the field; otherwise returns ``None``.
``Reverse`` ``Reverse``
=========== -----------
.. class:: Reverse(expression, **extra) .. class:: Reverse(expression, **extra)
@ -558,7 +317,7 @@ Accepts a single geographic field or expression and returns a geometry with
reversed coordinates. reversed coordinates.
``Rotate`` ``Rotate``
========== ----------
.. versionadded:: 6.0 .. versionadded:: 6.0
@ -571,7 +330,7 @@ rotation can be performed around a point, defined by the ``origin``
parameter. parameter.
``Scale`` ``Scale``
========= ---------
.. class:: Scale(expression, x, y, z=0.0, **extra) .. class:: Scale(expression, x, y, z=0.0, **extra)
@ -582,7 +341,7 @@ scaled coordinates by multiplying them with the ``x``, ``y``, and optionally
``z`` parameters. ``z`` parameters.
``SnapToGrid`` ``SnapToGrid``
============== --------------
.. class:: SnapToGrid(expression, *args, **extra) .. class:: SnapToGrid(expression, *args, **extra)
@ -602,22 +361,8 @@ Number of Arguments Description
4 X, Y sizes and the corresponding X, Y origins. 4 X, Y sizes and the corresponding X, Y origins.
=================== ===================================================== =================== =====================================================
``SymDifference``
=================
.. class:: SymDifference(expr1, expr2, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-operator-functions.html#function_st-symdifference>`__,
`PostGIS <https://postgis.net/docs/ST_SymDifference.html>`__, Oracle,
SpatiaLite
Accepts two geographic fields or expressions and returns the geometric
symmetric difference (union without the intersection) between the given
parameters.
``Transform`` ``Transform``
============= -------------
.. class:: Transform(expression, srid, **extra) .. class:: Transform(expression, srid, **extra)
@ -635,7 +380,7 @@ the transformed geometry to the spatial reference system specified by the
are not necessarily the same as those used by PostGIS. are not necessarily the same as those used by PostGIS.
``Translate`` ``Translate``
============= -------------
.. class:: Translate(expression, x, y, z=0.0, **extra) .. class:: Translate(expression, x, y, z=0.0, **extra)
@ -646,17 +391,278 @@ Accepts a single geographic field or expression and returns a geometry with
its coordinates offset by the ``x``, ``y``, and optionally ``z`` numeric its coordinates offset by the ``x``, ``y``, and optionally ``z`` numeric
parameters. parameters.
``Union`` Input format
========= ============
.. class:: Union(expr1, expr2, **extra) ``FromWKB``
-----------
.. class:: FromWKB(expression, srid=0, **extra)
*Availability*: MariaDB, `MySQL *Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-operator-functions.html#function_st-union>`__, <https://dev.mysql.com/doc/refman/en/gis-wkb-functions.html#function_st-geomfromwkb>`__,
`PostGIS <https://postgis.net/docs/ST_Union.html>`__, Oracle, SpatiaLite Oracle, `PostGIS <https://postgis.net/docs/ST_GeomFromWKB.html>`__, SpatiaLite
Accepts two geographic fields or expressions and returns the union of both Creates geometry from `Well-known binary (WKB)`_ representation. The optional
geometries. ``srid`` argument allows to specify the SRID of the resulting geometry.
``srid`` is ignored on Oracle.
.. _`Well-known binary (WKB)`: https://en.wikipedia.org/wiki/Well-known_text_representation_of_geometry#Well-known_binary ``FromWKT``
.. _`Well-known text (WKT)`: https://en.wikipedia.org/wiki/Well-known_text_representation_of_geometry -----------
.. class:: FromWKT(expression, srid=0, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-wkt-functions.html#function_st-geomfromtext>`__,
Oracle, `PostGIS <https://postgis.net/docs/ST_GeomFromText.html>`__, SpatiaLite
Creates geometry from `Well-known text (WKT)`_ representation. The optional
``srid`` argument allows to specify the SRID of the resulting geometry.
``srid`` is ignored on Oracle.
Output format
=============
``AsGeoJSON``
-------------
.. class:: AsGeoJSON(expression, bbox=False, crs=False, precision=8, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-geojson-functions.html#function_st-asgeojson>`__,
Oracle, `PostGIS <https://postgis.net/docs/ST_AsGeoJSON.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `GeoJSON
<https://geojson.org/>`_ representation of the geometry. Note that the result
is not a complete GeoJSON structure but only the ``geometry`` key content of a
GeoJSON structure. See also :doc:`/ref/contrib/gis/serializers`.
Example:
.. code-block:: pycon
>>> City.objects.annotate(json=AsGeoJSON("point")).get(name="Chicago").json
{"type":"Point","coordinates":[-87.65018,41.85039]}
===================== =====================================================
Keyword Argument Description
===================== =====================================================
``bbox`` Set this to ``True`` if you want the bounding box
to be included in the returned GeoJSON. Ignored on
Oracle.
``crs`` Set this to ``True`` if you want the coordinate
reference system to be included in the returned
GeoJSON. Ignored on MySQL and Oracle.
``precision`` It may be used to specify the number of significant
digits for the coordinates in the GeoJSON
representation -- the default value is 8. Ignored on
Oracle.
===================== =====================================================
``AsGML``
---------
.. class:: AsGML(expression, version=2, precision=8, **extra)
*Availability*: Oracle, `PostGIS <https://postgis.net/docs/ST_AsGML.html>`__,
SpatiaLite
Accepts a single geographic field or expression and returns a `Geographic Markup
Language (GML)`__ representation of the geometry.
Example:
.. code-block:: pycon
>>> qs = Zipcode.objects.annotate(gml=AsGML("poly"))
>>> print(qs[0].gml)
<gml:Polygon srsName="EPSG:4326"><gml:OuterBoundaryIs>-147.78711,70.245363 ...
-147.78711,70.245363</gml:OuterBoundaryIs></gml:Polygon>
===================== =====================================================
Keyword Argument Description
===================== =====================================================
``precision`` Specifies the number of significant digits for the
coordinates in the GML representation -- the default
value is 8. Ignored on Oracle.
``version`` Specifies the GML version to use: 2 (default) or 3.
===================== =====================================================
__ https://en.wikipedia.org/wiki/Geography_Markup_Language
``AsKML``
---------
.. class:: AsKML(expression, precision=8, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_AsKML.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `Keyhole Markup
Language (KML)`__ representation of the geometry.
Example:
.. code-block:: pycon
>>> qs = Zipcode.objects.annotate(kml=AsKML("poly"))
>>> print(qs[0].kml)
<Polygon><outerBoundaryIs><LinearRing><coordinates>-103.04135,36.217596,0 ...
-103.04135,36.217596,0</coordinates></LinearRing></outerBoundaryIs></Polygon>
===================== =====================================================
Keyword Argument Description
===================== =====================================================
``precision`` This keyword may be used to specify the number of
significant digits for the coordinates in the KML
representation -- the default value is 8.
===================== =====================================================
__ https://developers.google.com/kml/documentation/
``AsSVG``
---------
.. class:: AsSVG(expression, relative=False, precision=8, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_AsSVG.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `Scalable Vector
Graphics (SVG)`__ representation of the geometry.
===================== =====================================================
Keyword Argument Description
===================== =====================================================
``relative`` If set to ``True``, the path data will be implemented
in terms of relative moves. Defaults to ``False``,
meaning that absolute moves are used instead.
``precision`` This keyword may be used to specify the number of
significant digits for the coordinates in the SVG
representation -- the default value is 8.
===================== =====================================================
__ https://www.w3.org/Graphics/SVG/
``AsWKB``
---------
.. class:: AsWKB(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-format-conversion-functions.html#function_st-asbinary>`__,
Oracle, `PostGIS <https://postgis.net/docs/ST_AsBinary.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `Well-known
binary (WKB)`_ representation of the geometry.
Example:
.. code-block:: pycon
>>> bytes(City.objects.annotate(wkb=AsWKB("point")).get(name="Chelyabinsk").wkb)
b'\x01\x01\x00\x00\x00]3\xf9f\x9b\x91K@\x00X\x1d9\xd2\xb9N@'
``AsWKT``
---------
.. class:: AsWKT(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-format-conversion-functions.html#function_st-astext>`__,
Oracle, `PostGIS <https://postgis.net/docs/ST_AsText.html>`__, SpatiaLite
Accepts a single geographic field or expression and returns a `Well-known text
(WKT)`_ representation of the geometry.
Example:
.. code-block:: pycon
>>> City.objects.annotate(wkt=AsWKT("point")).get(name="Chelyabinsk").wkt
'POINT (55.137555 61.451728)'
``GeoHash``
-----------
.. class:: GeoHash(expression, precision=None, **extra)
*Availability*: `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-geohash-functions.html#function_st-geohash>`__,
`PostGIS <https://postgis.net/docs/ST_GeoHash.html>`__, SpatiaLite
(LWGEOM/RTTOPO)
Accepts a single geographic field or expression and returns a `GeoHash`__
representation of the geometry.
The ``precision`` keyword argument controls the number of characters in the
result.
__ https://en.wikipedia.org/wiki/Geohash
Miscellaneous
=============
``IsEmpty``
-----------
.. class:: IsEmpty(expr)
*Availability*: `PostGIS <https://postgis.net/docs/ST_IsEmpty.html>`__
Accepts a geographic field or expression and tests if the value is an empty
geometry. Returns ``True`` if its value is empty and ``False`` otherwise.
``IsValid``
-----------
.. class:: IsValid(expr)
*Availability*: `MySQL
<https://dev.mysql.com/doc/refman/en/spatial-convenience-functions.html#function_st-isvalid>`__,
`PostGIS <https://postgis.net/docs/ST_IsValid.html>`__, Oracle, SpatiaLite
Accepts a geographic field or expression and tests if the value is well formed.
Returns ``True`` if its value is a valid geometry and ``False`` otherwise.
``MemSize``
-----------
.. class:: MemSize(expression, **extra)
*Availability*: `PostGIS <https://postgis.net/docs/ST_MemSize.html>`__
Accepts a single geographic field or expression and returns the memory size
(number of bytes) that the geometry field takes.
``NumGeometries``
-----------------
.. class:: NumGeometries(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-geometrycollection-property-functions.html#function_st-numgeometries>`__,
`PostGIS <https://postgis.net/docs/ST_NumGeometries.html>`__, Oracle,
SpatiaLite
Accepts a single geographic field or expression and returns the number of
geometries if the geometry field is a collection (e.g., a ``GEOMETRYCOLLECTION``
or ``MULTI*`` field). Returns 1 for single geometries.
On MySQL, returns ``None`` for single geometries.
``NumPoints``
-------------
.. class:: NumPoints(expression, **extra)
*Availability*: MariaDB, `MySQL
<https://dev.mysql.com/doc/refman/en/gis-linestring-property-functions.html#function_st-numpoints>`__,
`PostGIS <https://postgis.net/docs/ST_NPoints.html>`__, Oracle, SpatiaLite
Accepts a single geographic field or expression and returns the number of points
in a geometry.
On MySQL, returns ``None`` for any non-``LINESTRING`` geometry.