turf-count
turf count module
turf.count(polygons, points, countField)
Takes a set of Point|points and a set of Polygon|polygons and calculates the number of points that fall within the set of polygons.
Parameters
| parameter | type | description |
|---|---|---|
polygons |
FeatureCollection.<Polygon> | input polygons |
points |
FeatureCollection.<Point> | input points |
countField |
String | a field to append to the attributes of the Polygon features representing Point counts |
Example
var polygons = {
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {},
"geometry": {
"type": "Polygon",
"coordinates": [[
[-112.072391,46.586591],
[-112.072391,46.61761],
[-112.028102,46.61761],
[-112.028102,46.586591],
[-112.072391,46.586591]
]]
}
}, {
"type": "Feature",
"properties": {},
"geometry": {
"type": "Polygon",
"coordinates": [[
[-112.023983,46.570426],
[-112.023983,46.615016],
[-111.966133,46.615016],
[-111.966133,46.570426],
[-112.023983,46.570426]
]]
}
}
]
};
var points = {
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"properties": {
"population": 200
},
"geometry": {
"type": "Point",
"coordinates": [-112.0372, 46.608058]
}
}, {
"type": "Feature",
"properties": {
"population": 600
},
"geometry": {
"type": "Point",
"coordinates": [-112.045955, 46.596264]
}
}
]
};
var counted = turf.count(polygons, points, 'pt_count');
var resultFeatures = points.features.concat(counted.features);
var result = {
"type": "FeatureCollection",
"features": resultFeatures
};
//=resultReturns FeatureCollection.<Polygon>, polygons with countField appended
Installation
Requires nodejs.
$ npm install turf-countTests
$ npm test
