@turf/invariant

getCoord

Unwrap a coordinate from a Point Feature, Geometry or a single coordinate.

Parameters

• coord (Array<number> | Geometry<Point> | Feature<Point>) GeoJSON Point or an Array of numbers

Examples

var pt = turf.point([10, 10]);

var coord = turf.getCoord(pt);
//= [10, 10]

Returns Array<number> coordinates

getCoords

Unwrap coordinates from a Feature, Geometry Object or an Array

Parameters

• coords (Array<any> | Geometry | Feature) Feature, Geometry Object or an Array

Examples

var poly = turf.polygon([[[119.32, -8.7], [119.55, -8.69], [119.51, -8.54], [119.32, -8.7]]]);

var coords = turf.getCoords(poly);
//= [[[119.32, -8.7], [119.55, -8.69], [119.51, -8.54], [119.32, -8.7]]]

Returns Array<any> coordinates

containsNumber

Checks if coordinates contains a number

Parameters

• coordinates Array<any> GeoJSON Coordinates

Returns boolean true if Array contains a number

geojsonType

Enforce expectations about types of GeoJSON objects for Turf.

Parameters

• value GeoJSON any GeoJSON object
• type string expected GeoJSON type
• name string name of calling function

• Throws Error if value is not the expected type.

Returns void

featureOf

Enforce expectations about types of Feature inputs for Turf. Internally this uses geojsonType to judge geometry types.

Parameters

• feature Feature a feature with an expected geometry type
• type string expected GeoJSON type
• name string name of calling function

• Throws Error error if value is not the expected type.

Returns void

collectionOf

Enforce expectations about types of FeatureCollection inputs for Turf. Internally this uses geojsonType to judge geometry types.

Parameters

• featureCollection FeatureCollection a FeatureCollection for which features will be judged
• type string expected GeoJSON type
• name string name of calling function

• Throws Error if value is not the expected type.

getGeom

Get Geometry from Feature or Geometry Object

Parameters

• geojson (Feature | Geometry) GeoJSON Feature or Geometry Object

Examples

var point = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "Point",
    "coordinates": [110, 40]
  }
}
var geom = turf.getGeom(point)
//={"type": "Point", "coordinates": [110, 40]}

• Throws Error if geojson is not a Feature or Geometry Object

Returns (Geometry | null) GeoJSON Geometry Object

getType

Get GeoJSON object's type, Geometry type is prioritize.

Parameters

• geojson GeoJSON GeoJSON object
• _name string?
• name string name of the variable to display in error message (unused) (optional, default "geojson")

Examples

var point = {
  "type": "Feature",
  "properties": {},
  "geometry": {
    "type": "Point",
    "coordinates": [110, 40]
  }
}
var geom = turf.getType(point)
//="Point"

Returns string GeoJSON type

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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/invariant

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

$ npm install @turf/turf