# @turf/line-overlap ## lineOverlap Takes any LineString or Polygon and returns the overlapping lines between both features. ### Parameters * `line1` **([Geometry][1] | [Feature][2]<([LineString][3] | [MultiLineString][4] | [Polygon][5] | [MultiPolygon][6])>)** any LineString or Polygon * `line2` **([Geometry][1] | [Feature][2]<([LineString][3] | [MultiLineString][4] | [Polygon][5] | [MultiPolygon][6])>)** any LineString or Polygon * `options` **[Object][7]** Optional parameters (optional, default `{}`) * `options.tolerance` **[number][8]** Tolerance distance to match overlapping line segments (in kilometers) (optional, default `0`) ### Examples ```javascript var line1 = turf.lineString([[115, -35], [125, -30], [135, -30], [145, -35]]); var line2 = turf.lineString([[115, -25], [125, -30], [135, -30], [145, -25]]); var overlapping = turf.lineOverlap(line1, line2); //addToMap var addToMap = [line1, line2, overlapping] ``` Returns **[FeatureCollection][9]<[LineString][3]>** lines(s) that are overlapping between both features [1]: https://tools.ietf.org/html/rfc7946#section-3.1 [2]: https://tools.ietf.org/html/rfc7946#section-3.2 [3]: https://tools.ietf.org/html/rfc7946#section-3.1.4 [4]: https://tools.ietf.org/html/rfc7946#section-3.1.5 [5]: https://tools.ietf.org/html/rfc7946#section-3.1.6 [6]: https://tools.ietf.org/html/rfc7946#section-3.1.7 [7]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object [8]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number [9]: https://tools.ietf.org/html/rfc7946#section-3.3 --- This module is part of the [Turfjs project](https://turfjs.org/), an open source module collection dedicated to geographic algorithms. It is maintained in the [Turfjs/turf](https://github.com/Turfjs/turf) repository, where you can create PRs and issues. ### Installation Install this single module individually: ```sh $ npm install @turf/line-overlap ``` Or install the all-encompassing @turf/turf module that includes all modules as functions: ```sh $ npm install @turf/turf ```