@nextgis/area

Area

Dependencies free QGIS ellipsoidal area calculation reproduced in JavaScript.

also look at the Python implementation

Installation

In Browser

Include assets

Simply download and include with a script tag, Area will be registered as a global variable.

<script src="../lib/area.global.js"></script>

<script>
  var area = Area.calculateArea([
    [51.82, 63.8],
    [43.48, 55.62],
    [75.38, 59.13],
    [51.82, 63.8], // the first and last positions MUST contain identical values
  ]);
  var area = Area.geojsonArea(geojson);
</script>

CDN

unpkg

<script src="https://unpkg.com/@nextgis/area"></script>

jsdelivr

<script src="https://cdn.jsdelivr.net/npm/@nextgis/area"></script>

We recommend linking to a specific version number /area@[version]

In Node.js

npm install @nextgis/area

Usage

import { calculateArea, geojsonArea } from '@nextgis/area';

const area = geojsonArea(geojson);
const area2 = calculateArea([
  [51.82, 63.8],
  [43.48, 55.62],
  [75.38, 59.13],
  [51.82, 63.8], // the first and last positions MUST contain identical values
]);
console.log(area2); // 730215205638.4752

Check out the API Documentation

Notes

Implementations and code in other software, languages

• NGQ 2.x QgsDistanceArea::computePolygonArea
• QGIS 3.x QgsDistanceArea::computePolygonArea
• GRASS G_ellipsoid_polygon_area
• pyproj geod_geninverse_int -> geod_polygon_compute -> geod_polygonarea -> _polygon_area_perimeter -> geometry_area_perimeter, Geodesic Routines Description, Docs

Commercial support

Need to fix a bug or add a feature to @nextgis/area? We provide custom development and support for this software. Contact us to discuss options!