What is @turf/centroid?
@turf/centroid is a module within the Turf.js library that calculates the centroid of a given GeoJSON feature. This is useful for finding the geometric center of various shapes such as polygons, lines, and multi-geometries.
What are @turf/centroid's main functionalities?
Calculate Centroid of a Polygon
This feature calculates the centroid of a polygon. The code sample demonstrates how to create a polygon and then calculate its centroid using the @turf/centroid package.
const turf = require('@turf/centroid');
const polygon = turf.polygon([[
[-81, 41],
[-81, 47],
[-72, 47],
[-72, 41],
[-81, 41]
]]);
const centroid = turf.centroid(polygon);
console.log(centroid);
Calculate Centroid of a LineString
This feature calculates the centroid of a LineString. The code sample demonstrates how to create a LineString and then calculate its centroid using the @turf/centroid package.
const turf = require('@turf/centroid');
const line = turf.lineString([
[-83, 30],
[-84, 36],
[-78, 41]
]);
const centroid = turf.centroid(line);
console.log(centroid);
Calculate Centroid of a MultiPolygon
This feature calculates the centroid of a MultiPolygon. The code sample demonstrates how to create a MultiPolygon and then calculate its centroid using the @turf/centroid package.
const turf = require('@turf/centroid');
const multiPolygon = turf.multiPolygon([[
[[-81, 41], [-81, 47], [-72, 47], [-72, 41], [-81, 41]]
], [
[[-73, 39], [-73, 45], [-64, 45], [-64, 39], [-73, 39]]
]]);
const centroid = turf.centroid(multiPolygon);
console.log(centroid);
Other packages similar to @turf/centroid
geolib
Geolib is a library for geospatial calculations. It provides functions to calculate distances, areas, and other geometric properties. While it offers centroid calculations, it is more general-purpose compared to @turf/centroid, which is specifically designed for GeoJSON features.
jsts
JSTS (JavaScript Topology Suite) is a library for performing various geometric operations. It includes functions for calculating centroids, but it is more complex and offers a broader range of geometric operations compared to @turf/centroid.
@turf/centroid
centroid
Takes one or more features and calculates the centroid using
the mean of all vertices.
This lessens the effect of small islands and artifacts when calculating
the centroid of a set of polygons.
Parameters
Examples
var poly = {
"type": "Feature",
"properties": {},
"geometry": {
"type": "Polygon",
"coordinates": [[
[105.818939,21.004714],
[105.818939,21.061754],
[105.890007,21.061754],
[105.890007,21.004714],
[105.818939,21.004714]
]]
}
};
var centroidPt = turf.centroid(poly);
var result = {
"type": "FeatureCollection",
"features": [poly, centroidPt]
};
Returns Feature<Point> the centroid of the input features
This module is part of the Turfjs project, an open source
module collection dedicated to geographic algorithms. It is maintained in the
Turfjs/turf repository, where you can create
PRs and issues.
Installation
Install this module individually:
$ npm install @turf/centroid
Or install the Turf module that includes it as a function:
$ npm install @turf/turf