wrongmove/immoweb/node_modules/@turf/helpers/README.md
2025-05-26 19:41:36 +00:00

10 KiB

@turf/helpers

feature

Wraps a GeoJSON Geometry in a GeoJSON Feature.

Parameters

Examples

var geometry = {
     "type": "Point",
     "coordinates": [
       67.5,
       32.84267363195431
     ]
   }

var feature = turf.feature(geometry);

//=feature

Returns FeatureCollection a FeatureCollection of input features

point

Takes coordinates and properties (optional) and returns a new Point feature.

Parameters

  • coordinates Array<number> longitude, latitude position (each in decimal degrees)
  • properties [Object] an Object that is used as the Feature's properties

Examples

var pt1 = turf.point([-75.343, 39.984]);

//=pt1

Returns Feature<Point> a Point feature

polygon

Takes an array of LinearRings and optionally an Object with properties and returns a Polygon feature.

Parameters

Examples

var polygon = turf.polygon([[
 [-2.275543, 53.464547],
 [-2.275543, 53.489271],
 [-2.215118, 53.489271],
 [-2.215118, 53.464547],
 [-2.275543, 53.464547]
]], { name: 'poly1', population: 400});

//=polygon
  • Throws Error throw an error if a LinearRing of the polygon has too few positions or if a LinearRing of the Polygon does not have matching Positions at the beginning & end.

Returns Feature<Polygon> a Polygon feature

lineString

Creates a LineString based on a coordinate array. Properties can be added optionally.

Parameters

  • coordinates Array<Array<number>> an array of Positions
  • properties [Object] an Object of key-value pairs to add as properties

Examples

var linestring1 = turf.lineString([
  [-21.964416, 64.148203],
  [-21.956176, 64.141316],
  [-21.93901, 64.135924],
  [-21.927337, 64.136673]
]);
var linestring2 = turf.lineString([
  [-21.929054, 64.127985],
  [-21.912918, 64.134726],
  [-21.916007, 64.141016],
  [-21.930084, 64.14446]
], {name: 'line 1', distance: 145});

//=linestring1

//=linestring2
  • Throws Error if no coordinates are passed

Returns Feature<LineString> a LineString feature

featureCollection

Takes one or more Features and creates a FeatureCollection.

Parameters

Examples

var features = [
 turf.point([-75.343, 39.984], {name: 'Location A'}),
 turf.point([-75.833, 39.284], {name: 'Location B'}),
 turf.point([-75.534, 39.123], {name: 'Location C'})
];

var fc = turf.featureCollection(features);

//=fc

Returns FeatureCollection a FeatureCollection of input features

multiLineString

Creates a Feature<MultiLineString> based on a coordinate array. Properties can be added optionally.

Parameters

  • coordinates Array<Array<Array<number>>> an array of LineStrings
  • properties [Object] an Object of key-value pairs to add as properties

Examples

var multiLine = turf.multiLineString([[[0,0],[10,10]]]);

//=multiLine
  • Throws Error if no coordinates are passed

Returns Feature<MultiLineString> a MultiLineString feature

multiPoint

Creates a Feature<MultiPoint> based on a coordinate array. Properties can be added optionally.

Parameters

  • coordinates Array<Array<number>> an array of Positions
  • properties [Object] an Object of key-value pairs to add as properties

Examples

var multiPt = turf.multiPoint([[0,0],[10,10]]);

//=multiPt
  • Throws Error if no coordinates are passed

Returns Feature<MultiPoint> a MultiPoint feature

multiPolygon

Creates a Feature<MultiPolygon> based on a coordinate array. Properties can be added optionally.

Parameters

Examples

var multiPoly = turf.multiPolygon([[[[0,0],[0,10],[10,10],[10,0],[0,0]]]]);

//=multiPoly
  • Throws Error if no coordinates are passed

Returns Feature<MultiPolygon> a multipolygon feature

geometryCollection

Creates a Feature<GeometryCollection> based on a coordinate array. Properties can be added optionally.

Parameters

  • geometries Array<{Geometry}> an array of GeoJSON Geometries
  • properties [Object] an Object of key-value pairs to add as properties

Examples

var pt = {
    "type": "Point",
      "coordinates": [100, 0]
    };
var line = {
    "type": "LineString",
    "coordinates": [ [101, 0], [102, 1] ]
  };
var collection = turf.geometryCollection([pt, line]);

//=collection

Returns Feature<GeometryCollection> a GeoJSON GeometryCollection Feature


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/helpers

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

$ npm install @turf/turf