@turf/invariant

getCoord

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

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* coord ([Array][1]<[number][2]> | [Geometry][3]<[Point][4]> | [Feature][5]<[Point][4]>) GeoJSON Point or an Array of numbers

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

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

Returns [Array][1]<[number][2]> coordinates

getCoords

Unwrap coordinates from a Feature, Geometry Object or an Array

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* coords ([Array][1]\ | [Geometry][3] | [Feature][5]) Feature, Geometry Object or an Array

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`javascript
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][1]\ coordinates

containsNumber

Checks if coordinates contains a number

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* coordinates [Array][1]\ GeoJSON Coordinates

Returns [boolean][6] true if Array contains a number

geojsonType

Enforce expectations about types of GeoJSON objects for Turf.

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* value [GeoJSON][7] any GeoJSON object
* type [string][8] expected GeoJSON type
* name [string][8] name of calling function

* Throws [Error][9] if value is not the expected type.

Returns void

featureOf

Enforce expectations about types of [Feature][5] inputs for Turf.
Internally this uses [geojsonType][10] to judge geometry types.

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* feature [Feature][5] a feature with an expected geometry type
* type [string][8] expected GeoJSON type
* name [string][8] name of calling function

* Throws [Error][9] error if value is not the expected type.

Returns void

collectionOf

Enforce expectations about types of [FeatureCollection][11] inputs for Turf.
Internally this uses [geojsonType][10] to judge geometry types.

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* featureCollection [FeatureCollection][11] a FeatureCollection for which features will be judged
* type [string][8] expected GeoJSON type
* name [string][8] name of calling function

* Throws [Error][9] if value is not the expected type.

getGeom

Get Geometry from Feature or Geometry Object

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* geojson ([Feature][5] | [Geometry][3]) GeoJSON Feature or Geometry Object

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

* Throws [Error][9] if geojson is not a Feature or Geometry Object

Returns ([Geometry][3] | null) GeoJSON Geometry Object

getType

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

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* geojson [GeoJSON][7] GeoJSON object
* _name [string][8]?
* name [string][8] name of the variable to display in error message (unused) (optional, default "geojson")

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

Returns [string][8] GeoJSON type

[1]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Array

[2]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Number

[3]: https://tools.ietf.org/html/rfc7946#section-3.1

[4]: https://tools.ietf.org/html/rfc7946#section-3.1.2

[5]: https://tools.ietf.org/html/rfc7946#section-3.2

[6]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean

[7]: https://tools.ietf.org/html/rfc7946#section-3

[8]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/String

[9]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Error

[10]: #geojsontype

[11]: https://tools.ietf.org/html/rfc7946#section-3.3

---

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.

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Install this single module individually:

`sh
$ npm install @turf/invariant
`

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

`sh
$ npm install @turf/turf
``