turf-count

turf count module

turf.count(polygons, points, countField)

Takes a FeatureCollection of Point features and a FeatureCollection of Polygon features and calculates the number of points that fall within the set of polygons.

Parameters

parameter	type	description
polygons	FeatureCollection	a FeatureCollection of Polygon features
points	FeatureCollection	a FeatureCollection of Point features
countField	String	a field to append to the attributes of the Polygon features representing Point counts

Example

var polygons = turf.featurecollection([
 turf.polygon([[
   [-112.072391,46.586591],
   [-112.072391,46.61761],
   [-112.028102,46.61761],
   [-112.028102,46.586591],
   [-112.072391,46.586591]
 ]]),
 turf.polygon([[
   [-112.023983,46.570426],
   [-112.023983,46.615016],
   [-111.966133,46.615016],
   [-111.966133,46.570426],
   [-112.023983,46.570426]
 ]])
]);
var points = turf.featurecollection([
 turf.point([-112.0372, 46.608058], {population: 200}),
 turf.point([-112.045955, 46.596264],
   {population: 600})
]);
 
var counted = turf.count(polygons, points, 'pt_count');
 
var result = turf.featurecollection(
  points.features.concat(counted.features));
 
//=result

Installation

Requires nodejs.

$ npm install turf-count

Tests

$ npm test