@turf/union

union

Takes input (Multi)Polygon(s) and returns a combined polygon. If the input polygons are not contiguous, this function returns a MultiPolygon feature.

Parameters

• polygon1 Feature<(Polygon | MultiPolygon)> input Polygon features

• options Object Optional Parameters (optional, default {})

  • options.properties Object Translate Properties to output Feature (optional, default {})

Examples

var poly1 = turf.polygon([[
    [-82.574787, 35.594087],
    [-82.574787, 35.615581],
    [-82.545261, 35.615581],
    [-82.545261, 35.594087],
    [-82.574787, 35.594087]
]], {"fill": "#0f0"});
var poly2 = turf.polygon([[
    [-82.560024, 35.585153],
    [-82.560024, 35.602602],
    [-82.52964, 35.602602],
    [-82.52964, 35.585153],
    [-82.560024, 35.585153]
]], {"fill": "#00f"});

var union = turf.union(turf.featureCollection([poly1, poly2]));

//addToMap
var addToMap = [poly1, poly2, union];

Returns Feature<(Polygon | MultiPolygon)> a combined Polygon or MultiPolygon feature, or null if the inputs are empty

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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 single module individually:

$ npm install @turf/union

Or install the all-encompassing @turf/turf module that includes all modules as functions:

$ npm install @turf/turf