tag

Takes a set of points and a set of polygons and performs a spatial join.
取一组点和一组多边形，并执行空间连接。

参数

参数	类型	描述
points	FeatureCollection <Point>	input points
polygons	FeatureCollection <Polygon>	input polygons
field	string	property in polygons to add to joined { } features
outField	string	property in points in which to store joined property from polygons

返回

FeatureCollection <Point> - points with containingPolyId property containing values from polyId

示例

var pt1 = turf.point([-77, 44]);
var pt2 = turf.point([-77, 38]);
var poly1 = turf.polygon([[
  [-81, 41], // 注意：polygon首尾坐标要一致
  [-81, 47],
  [-72, 47],
  [-72, 41],
  [-81, 41]
]], {pop: 3000});
var poly2 = turf.polygon([[
  [-81, 35],
  [-81, 41],
  [-72, 41],
  [-72, 35],
  [-81, 35]
]], {pop: 1000});

var points = turf.featureCollection([pt1, pt2]);
var polygons = turf.featureCollection([poly1, poly2]);

var tagged = turf.tag(points, polygons, 'pop', 'population');