@turf/along

What is @turf/along?

@turf/along is a module from the Turf.js library that allows you to calculate a point at a specified distance along a line. This can be useful for various geospatial analyses, such as finding a location a certain distance from a starting point on a path or route.

What are @turf/along's main functionalities?

Calculate a point along a line

This feature allows you to calculate a point that is a specified distance along a given line. In this example, a point 5 kilometers along the line is calculated.

const turf = require('@turf/turf');

const line = turf.lineString([[0, 0], [10, 10], [20, 20]]);
const distance = 5;
const options = { units: 'kilometers' };
const point = turf.along(line, distance, options);
console.log(point);

Other packages similar to @turf/along

geolib

Geolib is a library for geospatial calculations in JavaScript. It provides various functions for distance calculations, finding points within a certain radius, and more. Compared to @turf/along, geolib offers a broader range of geospatial utilities but may not be as specialized in line-based calculations.

geodesy

Geodesy is a library for geodesic calculations in JavaScript. It includes functions for calculating distances, bearings, and points along a path. While it offers similar functionality to @turf/along, it is more focused on geodesic calculations and may be more suitable for applications requiring high precision over long distances.

README

turf-along

along

Takes a line and returns a point at a specified distance along the line.

Parameters

• line Feature<LineString> input line
• distance number distance along the line
• units [String] can be degrees, radians, miles, or kilometers (optional, default miles)

Examples

var line = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "LineString",
    "coordinates": [
      [-77.031669, 38.878605],
      [-77.029609, 38.881946],
      [-77.020339, 38.884084],
      [-77.025661, 38.885821],
      [-77.021884, 38.889563],
      [-77.019824, 38.892368]
    ]
  }
};

var along = turf.along(line, 1, 'miles');

var result = {
  "type": "FeatureCollection",
  "features": [line, along]
};

//=result

Returns Feature<Point> Point distance units along the line

---

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-along

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

$ npm install turf