turf-max

turf max module

turf.max(polygons, points, inField, outField)

Calculates the maximum value of a field for points within a set of polygons.

Parameters

parameter	type	description
polygons	FeatureCollection	a FeatureCollection of Polygon features
points	FeatureCollection	a FeatureCollection of Point features
inField	string	the field in input data to analyze
outField	string	the field in which to store results

Example

var polygons = turf.featurecollection([
  turf.polygon([[
    [101.551437, 3.150114],
    [101.551437, 3.250208],
    [101.742324, 3.250208],
    [101.742324, 3.150114],
    [101.551437, 3.150114]
  ]]),
  turf.polygon([[
    [101.659927, 3.011612],
    [101.659927, 3.143944],
    [101.913986, 3.143944],
    [101.913986, 3.011612],
    [101.659927, 3.011612]
  ]])
]);
var points = turf.featurecollection([
  turf.point([101.56105, 3.213874], {population: 200}),
  turf.point([101.709365, 3.211817], {population: 600}),
  turf.point([101.645507, 3.169311], {population: 100}),
  turf.point([101.708679, 3.071266], {population: 200}),
  turf.point([101.826782, 3.081551], {population: 300})]);
 
var aggregated = turf.max(
  polygons, points, 'population', 'max');
 
var result = turf.featurecollection(
  points.features.concat(aggregated.features));
 
//=result

Installation

Requires nodejs.

$ npm install turf-max

Tests

$ npm test