概述

函数pointInPolygon()判断一个二维坐标点是否位于一个多边形区域内。

参数：pointInPolygon(<point>, <polygon>)

• <point>：坐标对象（point或list类型）
• <polygon>：多边形区域（list类型）

返回值：

• 判断结果，1（是）或0（否）
• 点落在区域边界上的视为否

一般用法

本例使用异源别名计算：

uncollect [[1.5,0.5],[2,2]] as point
uncollect [[[1,0],[3,0],[3,1],[1,1]],[[1,0],[2,1],[1,2],[0,1]]] as polygon
return table(toString(point), toString(polygon), pointInPolygon(point, polygon))

| toString(point) |     toString(polygon)     | pointInPolygon(point, polygon) |
|-----------------|---------------------------|--------------------------------|
| [1.5,0.5]       | [[1,0],[3,0],[3,1],[1,1]] | 1                              |
| [2,2]           | [[1,0],[2,1],[1,2],[0,1]] | 0                              |

本例将异源别名做笛卡尔积组合后计算：

uncollect [[1.5,0.5],[2,2]] as point
uncollect [[[1,0],[3,0],[3,1],[1,1]],[[1,0],[2,1],[1,2],[0,1]]] as polygon
with pointInPolygon(point, polygon) as result
return table(toString(point), toString(polygon), result)

| toString(point) |     toString(polygon)     | result |
|-----------------|---------------------------|--------|
| [1.5,0.5]       | [[1,0],[3,0],[3,1],[1,1]] | 1      |
| [1.5,0.5]       | [[1,0],[2,1],[1,2],[0,1]] | 0      |
| [2,2]           | [[1,0],[3,0],[3,1],[1,1]] | 0      |
| [2,2]           | [[1,0],[2,1],[1,2],[0,1]] | 0      |