ST_Envelope

定義

ST_Envelope は、ジオメトリ オブジェクトの最小範囲ボックスをポリゴンとして返します。

詳細:

この関数は、ST_Envelope がポリゴンを返すことを指定した OGC (Open Geospatial Consortium) のシンプル フィーチャ仕様に準拠しています。ST_Envelope 関数は、ポイント ジオメトリまたは水平線や垂直線といった特殊な場合で機能するように、これらの形状の周囲にあるポリゴンを返します。このポリゴンは、ジオメトリの空間参照系の XY 縮尺係数に基づいて計算される、小さなエンベロープの許容範囲です。この許容範囲は、これらの形状の周囲のポリゴンを返すために、最小 XY 座標から差し引かれ、最大 XY 座標に加算されます。

構文

Oracle および PostgreSQL

sde.st_envelope (geometry1 sde.st_geometry)

SQLite

st_envelope (geometry1 geometryblob)

戻り値のタイプ

Oracle および PostgreSQL

ST_Geometry

SQLite

Geometryblob

例

envelope_test テーブルの geotype 列は、g1 列に格納されるジオメトリ サブクラスの名前を格納します。INSERT ステートメントは、各ジオメトリ サブクラスを envelope_test テーブルに挿入します。

次に、ST_Envelope 関数が実行され、各ジオメトリの周囲にあるポリゴン エンベロープを返します。

Oracle

--Create table and insert values.
CREATE TABLE envelope_test (
 geotype varchar(20),
 g1 sde.st_geometry
);

INSERT INTO ENVELOPE_TEST VALUES (
'Point',
sde.st_geometry ('point (-1509734.232 -36684.757)', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Linestring',
sde.st_geometry ('linestring (-1511144.181 -37680.015, -1509734.232 -38841.149, -1508656.036 -39753.469)', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Polygon',
sde.st_geometry ('polygon ((-1506333.768 -36435.943, -1504343.252 -36767.695, -1502684.489 -35357.747, -1506333.768 -36435.943))', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Multipoint',
sde.st_geometry ('multipoint (-1493229.539 -40665.789, -1494141.859 -40831.665, -1495800.622 -42739.242)', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Multilinestring',
sde.st_geometry ('multilinestring ((-1504757.943 -33201.355, -1507411.964 -35606.561), (-1502518.613 -38094.706, -1499781.653 -37099.448, -1498952.272 -34694.241))', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Multipolygon',
sde.st_geometry ('multipolygon (((-1492068.405 -47300.841, -1492814.848 -45725.016, -1493975.983 -46471.459,
-1493478.354 -47798.47, -1492068.405 -47300.841), (-1497874.076 -48047.284, -1498537.581 -50618.367, -1497210.571 -50037.8,
-1497874.076 -48047.284)))', 102004)
);

--Return the polygon envelope around each geometry in well-known text.
SELECT geotype geometry_type,
 sde.st_astext (sde.st_envelope (g1)) envelope
 FROM ENVELOPE_TEST;

GEOMETRY_TYPE    ENVELOPE
 
Point           |POLYGON (( -1509734.23220000 -36684.75720000, -1509734.23180000 -36684.75720000, 
-1509734.23180000 -36684.75680000, -1509734.23220000 -36684.75680000, -1509734.23220000 -36684.75720000))

Linestring      |POLYGON (( -1511144.18100000 -39753.46900000, -1508656.03600000 -39753.46900000, 
-1508656.03600000 -37680.01500000, -1511144.18100000 -37680.01500000, -1511144.18100000 -39753.46900000))

Polygon         |POLYGON (( -1506333.76800000 -36767.69500000, -1502684.48900000 -36767.69500000, 
-1502684.48900000 -35357.74700000, -1506333.76800000 -35357.74700000, -1506333.76800000 -36767.69500000))

Multipoint      |POLYGON (( -1495800.62200000 -42739.24200000, -1493229.53900000 -42739.24200000, 
-1493229.53900000 -40665.78900000, -1495800.62200000 -40665.78900000, -1495800.62200000 -42739.24200000))

Multilinestring |POLYGON (( -1507411.96400000 -38094.70600000, -1498952.27200000 -38094.70600000, 
-1498952.27200000 -33201.35500000, -1507411.96400000 -33201.35500000, -1507411.96400000 -38094.70600000))

Multipolygon    |POLYGON (( -1498537.58100000 -50618.36700000, -1492068.40500000 -50618.36700000, 
-1492068.40500000 -45725.01600000, -1498537.58100000 -45725.01600000, -1498537.58100000 -50618.36700000))

PostgreSQL

--Create table and insert values.
CREATE TABLE envelope_test (
 geotype varchar(20),
 g1 sde.st_geometry
);

INSERT INTO ENVELOPE_TEST VALUES (
'Point',
sde.st_geometry ('point (-1509734.232 -36684.757)', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Linestring',
sde.st_geometry ('linestring (-1511144.181 -37680.015, -1509734.232 -38841.149, -1508656.036 -39753.469)', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Polygon',
sde.st_geometry ('polygon ((-1506333.768 -36435.943, -1504343.252 -36767.695, -1502684.489 -35357.747, -1506333.768 -36435.943))', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Multipoint',
sde.st_geometry ('multipoint (-1493229.539 -40665.789, -1494141.859 -40831.665, -1495800.622 -42739.242)', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Multilinestring',
sde.st_geometry ('multilinestring ((-1504757.943 -33201.355, -1507411.964 -35606.561), (-1502518.613 -38094.706, -1499781.653 -37099.448, -1498952.272 -34694.241))', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
'Multipolygon',
sde.st_geometry ('multipolygon (((-1492068.405 -47300.841, -1492814.848 -45725.016, -1493975.983 -46471.459,
-1493478.354 -47798.47, -1492068.405 -47300.841), (-1497874.076 -48047.284, -1498537.581 -50618.367, -1497210.571 -50037.8,
-1497874.076 -48047.284)))', 102004)
);

--Return the polygon envelope around each geometry in well-known text.
SELECT geotype AS geometry_type, 
 sde.st_astext (sde.st_envelope (g1)) AS Envelope
 FROM envelope_test;

geometry_type     envelope

"Point"           |"POLYGON (( -1509734.23220000 -36684.75720000, -1509734.23180000 -36684.75720000, 
-1509734.23180000 -36684.75680000, -1509734.23220000 -36684.75680000, -1509734.23220000 -36684.75720000))"

"Linestring"      |"POLYGON (( -1511144.18100000 -39753.46900000, -1508656.03600000 -39753.46900000, 
-1508656.03600000 -37680.01500000, -1511144.18100000 -37680.01500000, -1511144.18100000 -39753.46900000))"

"Polygon"         |"POLYGON (( -1506333.76800000 -36767.69500000, -1502684.48900000 -36767.69500000, 
-1502684.48900000 -35357.74700000, -1506333.76800000 -35357.74700000, -1506333.76800000 -36767.69500000))"

"Multipoint"      |"POLYGON (( -1495800.62200000 -42739.24200000, -1493229.53900000 -42739.24200000, 
-1493229.53900000 -40665.78900000, -1495800.62200000 -40665.78900000, -1495800.62200000 -42739.24200000))"

"Multilinestring" |"POLYGON (( -1507411.96400000 -38094.70600000, -1498952.27200000 -38094.70600000, 
-1498952.27200000 -33201.35500000, -1507411.96400000 -33201.35500000, -1507411.96400000 -38094.70600000))"

"Multipolygon"    |"POLYGON (( -1498537.58100000 -50618.36700000, -1492068.40500000 -50618.36700000, 
-1492068.40500000 -45725.01600000, -1498537.58100000 -45725.01600000, -1498537.58100000 -50618.36700000))"

SQLite

--Create table and insert values.
CREATE TABLE envelope_test (
 geotype varchar(20)
);

SELECT AddGeometryColumn (
 NULL,
 'envelope_test',
 'g1',
 4326,
 'geometry',
 'xy',
 'null'
);

INSERT INTO ENVELOPE_TEST VALUES (
 'Point',
 st_geometry ('point (-1509734.232 -36684.757)', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
 'Linestring',
 st_geometry ('linestring (-1511144.181 -37680.015, -1509734.232 -38841.149, -1508656.036 -39753.469)', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
 'Polygon',
 st_geometry ('polygon ((-1506333.768 -36435.943, -1504343.252 -36767.695, -1502684.489 -35357.747, -1506333.768 -36435.943))', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
 'Multipoint',
 st_geometry ('multipoint (-1493229.539 -40665.789, -1494141.859 -40831.665, -1495800.622 -42739.242)', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
 'Multilinestring',
 st_geometry ('multilinestring ((-1504757.943 -33201.355, -1507411.964 -35606.561), (-1502518.613 -38094.706, -1499781.653 -37099.448, -1498952.272 -34694.241))', 102004)
);

INSERT INTO ENVELOPE_TEST VALUES (
 'Multipolygon',
 st_geometry ('multipolygon (((-1492068.405 -47300.841, -1492814.848 -45725.016, -1493975.983 -46471.459,
-1493478.354 -47798.47, -1492068.405 -47300.841), (-1497874.076 -48047.284, -1498537.581 -50618.367, -1497210.571 -50037.8,
-1497874.076 -48047.284)))', 102004)
);

--Return the polygon envelope around each geometry in well-known text.
SELECT geotype AS geometry_type, 
 st_astext (st_envelope (g1)) AS "Envelope"
 FROM envelope_test;

geometry_type   Envelope

Point           POLYGON (( -1509734.23220000 -36684.75720000, -1509734.23180000 -36684.75720000, 
-1509734.23180000 -36684.75680000, -1509734.23220000 -36684.75680000, -1509734.23220000 -36684.75720000))

Linestring      POLYGON (( -1511144.18100000 -39753.46900000, -1508656.03600000 -39753.46900000, 
-1508656.03600000 -37680.01500000, -1511144.18100000 -37680.01500000, -1511144.18100000 -39753.46900000))

Polygon         POLYGON (( -1506333.76800000 -36767.69500000, -1502684.48900000 -36767.69500000, 
-1502684.48900000 -35357.74700000, -1506333.76800000 -35357.74700000, -1506333.76800000 -36767.69500000))

Multipoint      POLYGON (( -1495800.62200000 -42739.24200000, -1493229.53900000 -42739.24200000, 
-1493229.53900000 -40665.78900000, -1495800.62200000 -40665.78900000, -1495800.62200000 -42739.24200000))

Multilinestring POLYGON (( -1507411.96400000 -38094.70600000, -1498952.27200000 -38094.70600000, 
-1498952.27200000 -33201.35500000, -1507411.96400000 -33201.35500000, -1507411.96400000 -38094.70600000))

Multipolygon    POLYGON (( -1498537.58100000 -50618.36700000, -1492068.40500000 -50618.36700000, 
-1492068.40500000 -45725.01600000, -1498537.58100000 -45725.01600000, -1498537.58100000 -50618.36700000))