@turf/flip

What is @turf/flip?

@turf/flip is a module in the Turf.js library that allows you to flip the coordinates of GeoJSON objects. This is useful when you need to switch the order of latitude and longitude coordinates.

What are @turf/flip's main functionalities?

Flip Coordinates of a Point

This feature allows you to flip the coordinates of a GeoJSON Point object. The code sample demonstrates how to flip the coordinates of a point from [120.0, 30.0] to [30.0, 120.0].

const turf = require('@turf/turf');
const point = turf.point([120.0, 30.0]);
const flippedPoint = turf.flip(point);
console.log(flippedPoint);

Flip Coordinates of a LineString

This feature allows you to flip the coordinates of a GeoJSON LineString object. The code sample demonstrates how to flip the coordinates of a line from [[120.0, 30.0], [121.0, 31.0]] to [[30.0, 120.0], [31.0, 121.0]].

const turf = require('@turf/turf');
const line = turf.lineString([[120.0, 30.0], [121.0, 31.0]]);
const flippedLine = turf.flip(line);
console.log(flippedLine);

Flip Coordinates of a Polygon

This feature allows you to flip the coordinates of a GeoJSON Polygon object. The code sample demonstrates how to flip the coordinates of a polygon from [[[120.0, 30.0], [121.0, 31.0], [122.0, 32.0], [120.0, 30.0]]] to [[[30.0, 120.0], [31.0, 121.0], [32.0, 122.0], [30.0, 120.0]]].

const turf = require('@turf/turf');
const polygon = turf.polygon([[[120.0, 30.0], [121.0, 31.0], [122.0, 32.0], [120.0, 30.0]]]);
const flippedPolygon = turf.flip(polygon);
console.log(flippedPolygon);

Other packages similar to @turf/flip

geojson-rewind

The geojson-rewind package is used to enforce the winding order of GeoJSON polygons. While it doesn't flip coordinates, it ensures that the coordinates follow the right-hand rule. This is different from @turf/flip, which specifically flips the order of latitude and longitude.

geojson-normalize

The geojson-normalize package is used to normalize various GeoJSON objects into a consistent format. While it doesn't flip coordinates, it ensures that the GeoJSON objects are in a standard format. This is different from @turf/flip, which specifically flips the order of latitude and longitude.

README

@turf/flip

flip

Takes input features and flips all of their coordinates from [x, y] to [y, x].

Parameters

• input (Feature | FeatureCollection) input features

Examples

var serbia = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "Point",
    "coordinates": [20.566406, 43.421008]
  }
};

//=serbia

var saudiArabia = turf.flip(serbia);

//=saudiArabia

Returns (Feature | FeatureCollection) a feature or set of features of the same type as input with flipped coordinates

---

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/flip

Or install the Turf module that includes it as a function:

$ npm install @turf/turf