Get the convex hull of a geometry（获取几何体的凸包（convex hull））¶

Supported in: Batch, Faster, Streaming

Given a valid GeoJSON input string, return a GeoJSON string that is the convex hull for the geometry. The convex hull is the smallest convex polygon containing the geometry.

Expression categories: Geospatial

Declared arguments¶

Expression: GeoJSON values for which the convex hull is calculated.
Expression\

Output type: Geometry

Examples¶

Example 1: Base case¶

Argument values:

Expression: geometry

geometry	Output
{"type":"Polygon","coordinates":[[[0.0,0.0],[2.0,0.0],[2.0,1.0],[1.0,1.0],[1.0,2.0],[0.0,2.0],[0.0,0.0]]]}	{"type":"Polygon", "coordinates":[[[0.0, 0.0], [0.0, 2.0], [1.0, 2.0], [2.0, 1.0], [2.0, 0.0], [0.0, 0.0]]]}
null	null

Example 2: Base case¶

Argument values:

Expression: geometry

geometry	Output
{"type":"Polygon","coordinates":[[[0.0,0.0],[1.0,0.0],[0.0,1.0],[0.0,0.0]]]}	{"type":"Polygon","coordinates":[[[0.0, 0.0], [0.0, 1.0], [1.0, 0.0], [0.0, 0.0]]]}

Example 3: Base case¶

Argument values:

Expression: geometry

geometry	Output
{"type":"MultiPolygon","coordinates":[[[[0.0,0.0],[1.0,0.0],[1.0,1.0],[0.0,1.0],[0.0,0.0]]],[[[2.0,0.0],[3.0,0.0],[3.0,1.0],[2.0,1.0],[2.0,0.0]]]]}	{"type":"Polygon", "coordinates":[[[0.0, 0.0], [0.0, 1.0], [3.0, 1.0], [3.0, 0.0],[0.0, 0.0]]]}

Example 4: Base case¶

Argument values:

Expression: geometry

geometry	Output
{"type":"MultiPoint","coordinates":[[0.0,0.0],[0.0,1.0],[2.0,0.0], [2.0,1.0]]}	{"type":"Polygon","coordinates":[[[0.0, 0.0], [0.0, 1.0], [2.0, 1.0], [2.0, 0.0], [0.0, 0.0]]]}

中文翻译¶

获取几何体的凸包（convex hull）¶

支持：批处理（Batch）、快速处理（Faster）、流处理（Streaming）

给定一个有效的 GeoJSON 输入字符串，返回该几何体的凸包（convex hull）对应的 GeoJSON 字符串。凸包是包含该几何体的最小凸多边形。

表达式类别： 地理空间（Geospatial）

声明的参数¶

表达式（Expression）： 用于计算凸包的 GeoJSON 值。
表达式\

输出类型： Geometry

示例¶

示例 1：基础情况¶

参数值：

表达式： geometry

geometry	输出
{"type":"Polygon","coordinates":[[[0.0,0.0],[2.0,0.0],[2.0,1.0],[1.0,1.0],[1.0,2.0],[0.0,2.0],[0.0,0.0]]]}	{"type":"Polygon", "coordinates":[[[0.0, 0.0], [0.0, 2.0], [1.0, 2.0], [2.0, 1.0], [2.0, 0.0], [0.0, 0.0]]]}
null	null

示例 2：基础情况¶

参数值：

表达式： geometry

geometry	输出
{"type":"Polygon","coordinates":[[[0.0,0.0],[1.0,0.0],[0.0,1.0],[0.0,0.0]]]}	{"type":"Polygon","coordinates":[[[0.0, 0.0], [0.0, 1.0], [1.0, 0.0], [0.0, 0.0]]]}

示例 3：基础情况¶

参数值：

表达式： geometry

geometry	输出
{"type":"MultiPolygon","coordinates":[[[[0.0,0.0],[1.0,0.0],[1.0,1.0],[0.0,1.0],[0.0,0.0]]],[[[2.0,0.0],[3.0,0.0],[3.0,1.0],[2.0,1.0],[2.0,0.0]]]]}	{"type":"Polygon", "coordinates":[[[0.0, 0.0], [0.0, 1.0], [3.0, 1.0], [3.0, 0.0],[0.0, 0.0]]]}

示例 4：基础情况¶

参数值：

表达式： geometry

geometry	输出
{"type":"MultiPoint","coordinates":[[0.0,0.0],[0.0,1.0],[2.0,0.0], [2.0,1.0]]}	{"type":"Polygon","coordinates":[[[0.0, 0.0], [0.0, 1.0], [2.0, 1.0], [2.0, 0.0], [0.0, 0.0]]]}