@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 kilometers)

Examples

var line = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "LineString",
    "coordinates": [[-83, 30], [-84, 36], [-78, 41]]
  }
};

var along = turf.along(line, 200, 'miles');

//addToMap
var addToMap = [along, line]

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/turf

Changelog

4.5.0

🚀 New Modules

• @turf/clusters Takes a set of points and partition them into clusters using the k-means clustering algorithm. (PR https://github.com/Turfjs/turf/pull/787 - Author @stebogit )

• @turf/boolean-disjoint Boolean-disjoint returns (TRUE) if the intersection of the two geometries is an empty set. (PR https://github.com/Turfjs/turf/pull/805 - Author @rowanwins)

• @turf/boolean-contains Boolean-contains returns True if the second geometry is completely contained by the first geometry. The interiors of both geometries must intersect and, the interior and boundary of the secondary (geometry b) must not intersect the exterior of the primary (geometry a). Boolean-contains returns the exact opposite result of the @turf/boolean-within. (PR https://github.com/Turfjs/turf/pull/797 - Author @rowanwins)

• @turf/boolean-crosses Boolean-Crosses returns True if the intersection results in a geometry whose dimension is one less than the maximum dimension of the two source geometries and the intersection set is interior to both source geometries. Boolean-Crosses returns t (TRUE) for only multipoint/polygon, multipoint/linestring, linestring/linestring, linestring/polygon, and linestring/multipolygon comparisons. (PR https://github.com/Turfjs/turf/pull/796 - Author @rowanwins)

• @turf/boolean-clockwise Takes a ring and return true or false whether or not the ring is clockwise or counter-clockwise. (PR https://github.com/Turfjs/turf/pull/789 - Authors @morganherlocker @stebogit)

• @turf/clone Prevents GeoJSON coordinates from being mutated, similar to JSON.parse(JSON.stringify(geojson)). Only cloning the coordinates can be 3x-20x faster than the parse + stringify approach. (PR https://github.com/Turfjs/turf/pull/824 - Author @DenisCarriere)

🏅 New Features/Enhancements

• convertArea Converts a area to the requested unit. (PR https://github.com/Turfjs/turf/pull/821 - Author @wnordmann)
• Adds mask option to @turf/point-grid (PR https://github.com/Turfjs/turf/pull/791)
• New @turf/isolines based on MarchingSquares.js (PR https://github.com/Turfjs/turf/pull/781)
• Use ES6 modules / Add module.js to @turf/turf (PR https://github.com/Turfjs/turf/pull/793)
• Create-new-module script (PR https://github.com/Turfjs/turf/pull/823)

🐛 Bug Fixes

• Buffer - Drop circle buffer operation (PR https://github.com/Turfjs/turf/pull/786)
• Fixes @turf/idw bad property name #774 (PR https://github.com/Turfjs/turf/pull/800)
• Fix for @turf/polygon-tangents - Resolves #785 (PR https://github.com/Turfjs/turf/pull/792)