@turf/ellipse

@turf/ellipse

ellipse

Takes a Point and calculates the ellipse polygon given two semi-axes expressed in variable units and steps for precision.

Parameters

• center (Feature<Point> | Array<number>) center point
• xSemiAxis number semi (major) axis of the ellipse along the x-axis
• ySemiAxis number semi (minor) axis of the ellipse along the y-axis
• options Object Optional parameters (optional, default {})
  • options.angle number angle of rotation (along the vertical axis), from North in decimal degrees, negative clockwise (optional, default 0)
  • options.pivot (Geometry | Feature<Point> | Array<number>) point around which the rotation will be performed (optional, default 'origin')
  • options.steps number number of steps (optional, default 64)
  • options.units string unit of measurement for axes (optional, default 'kilometers')
  • options.properties Object properties (optional, default {})

Examples

var center = [-75, 40];
var xSemiAxis = 5;
var ySemiAxis = 2;
var ellipse = turf.ellipse(center, xSemiAxis, ySemiAxis);

//addToMap
var addToMap = [turf.point(center), ellipse]

Returns Feature<Polygon> ellipse polygon

---

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/ellipse

Or install the Turf module that includes it as a function:

$ npm install @turf/turf

Changelog

5.0.0 🎉

⭐️ Major Updates

• TurfJS now supports ES Modules (Related PR's)
• Optional parameters are now defined as an Object.

🚀 New Modules

[@turf/voronoi][voronoi]

Takes a FeatureCollection of points, and a bounding box, and returns a FeatureCollection of Voronoi polygons. (PR https://github.com/Turfjs/turf/pull/1043 - Author @stevage)

[@turf/shortest-path][shortest-path]

Returns the shortest path from start to end without colliding with any feature in obstacles (PR https://github.com/Turfjs/turf/pull/956 - Author @stebogit)

[@turf/boolean-parallel][boolean-parallel]

Boolean-Parallel returns True if each segment of line1 is parallel to the correspondent segment of line2 (PR https://github.com/Turfjs/turf/pull/941 - Author @stebogit)

[@turf/nearest-point-on-line][nearest-point-on-line]

Takes a {@link Point} and a {@link LineString} and calculates the closest Point on the (Multi)LineString. (PR https://github.com/Turfjs/turf/pull/939 - Author @stebogit)

🏅 New Features/Enhancements

• Updates [@turf/unkink-polygon][unkink-polygon] testing & added flattenEach instead of using flatten. (PR https://github.com/Turfjs/turf/pull/889)

• Add multi-geomtry support to @turf/line-split (PR https://github.com/Turfjs/turf/pull/1078)

• Improve @turf/meta lineEach method to provide properties, id and bbox (PR https://github.com/Turfjs/turf/pull/1010)

🐛 Bug Fixes

• Fixes @turf/helpers earth radius variable (PR https://github.com/Turfjs/turf/pull/1012)

• Fixes @turf/polygon-tangents bug (PR https://github.com/Turfjs/turf/pull/1058)

• Fixes @turf/line-chunk bug when the number of segments is integer (PR https://github.com/Turfjs/turf/pull/1046)

• Fixes segmentEach and segmentReduce methods in @turf/meta to ensure something is returned (PR https://github.com/Turfjs/turf/pull/968)

⚠️ Breaking Change

• Optional parameters are now defined as an Object:

Before

var from = [-75.343, 39.984];
var to = [-75.534, 39.123];
var units = 'miles';
var distance = turf.distance(from, to, units);

After

var from = [-75.343, 39.984];
var to = [-75.534, 39.123];
var options = {units: 'miles'};
var distance = turf.distance(from, to, options);

• Reworked @turf/random PR https://github.com/Turfjs/turf/issues/994
• Deprecate @turf/idw Issue https://github.com/Turfjs/turf/issues/887
• Reworked Grid modules @turf/point-grid/hex/square/triangle PR https://github.com/Turfjs/turf/pull/1029
• Renamed Modules/Methods
  • [x] @turf/inside => @turf/boolean-point-in-polygon https://github.com/Turfjs/turf/issues/860#issuecomment-317216235
  • [x] @turf/within => @turf/points-within-polygon https://github.com/Turfjs/turf/issues/860#issuecomment-317216235
  • [x] @turf/bezier => @turf/bezier-spline Issue https://github.com/Turfjs/turf/issues/661
  • [x] @turf/nearest => @turf/nearest-point https://github.com/Turfjs/turf/pull/858#issuecomment-317197295
  • [x] @turf/point-on-line => @turf/nearest-point-on-line https://github.com/Turfjs/turf/pull/858#issuecomment-317197295
  • [x] @turf/lineDistance => @turf/length https://github.com/Turfjs/turf/issues/860#issuecomment-317229869
  • [x] @turf/helpers
    • [x] radians2degrees => radiansToDegrees
    • [x] degrees2radians => degreesToRadians
    • [x] distanceToDegrees => lengthToDegrees
    • [x] distanceToRadians => lengthToRadians
    • [x] radiansToDistance => radiansToLength
    • [x] bearingToAngle => bearingToAzimuth
    • [x] convertDistance => convertLength