# @turf/dissolve ## dissolve Dissolves a FeatureCollection of [Polygon][1] features, filtered by an optional property name:value. Note that [MultiPolygon][2] features within the collection are not supported ### Parameters * `fc` **[FeatureCollection][3]<[Polygon][1]>** * `options` **[Object][4]** Optional parameters (optional, default `{}`) * `options.propertyName` **[string][5]?** features with the same `propertyName` value will be dissolved. * `featureCollection` **[FeatureCollection][3]<[Polygon][1]>** input feature collection to be dissolved ### Examples ```javascript var features = turf.featureCollection([ turf.polygon([[[0, 0], [0, 1], [1, 1], [1, 0], [0, 0]]], {combine: 'yes'}), turf.polygon([[[0, -1], [0, 0], [1, 0], [1, -1], [0,-1]]], {combine: 'yes'}), turf.polygon([[[1,-1],[1, 0], [2, 0], [2, -1], [1, -1]]], {combine: 'no'}), ]); var dissolved = turf.dissolve(features, {propertyName: 'combine'}); //addToMap var addToMap = [features, dissolved] ``` Returns **[FeatureCollection][3]<[Polygon][1]>** a FeatureCollection containing the dissolved polygons [1]: https://tools.ietf.org/html/rfc7946#section-3.1.6 [2]: https://tools.ietf.org/html/rfc7946#section-3.1.7 [3]: https://tools.ietf.org/html/rfc7946#section-3.3 [4]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Object [5]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String --- 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/dissolve ``` Or install the all-encompassing @turf/turf module that includes all modules as functions: ```sh $ npm install @turf/turf ```