# GeographicCoordinates

``public struct GeographicCoordinates``

The GeographicCoordinates object encompasses the basic elements of a location on Earth, including its altitude.

• ``` longitude ```

Undocumented

#### Declaration

Swift

``public let longitude: Degree``
• ``` latitude ```

Undocumented

#### Declaration

Swift

``public let latitude: Degree``
• ``` altitude ```

Undocumented

#### Declaration

Swift

``public let altitude: Meter``
• ``` location ```

Returns the equivalent CLLocation object. Note the minus sign on longitude.

#### Declaration

Swift

``public var location: CLLocation { get }``
• ``` zero ```

Convenience method

#### Declaration

Swift

``public static var zero: GeographicCoordinates { get }``
• ``` init(positivelyWestwardLongitude:latitude:altitude:) ```

Returns a GeographicCoordinates object.

#### Declaration

Swift

``public init(positivelyWestwardLongitude longitude: Degree, latitude: Degree, altitude: Meter = 0)``

#### Parameters

 ``` longitude ``` The (positively westward) longitude. ``` latitude ``` The latitude ``` altitude ``` The optional altitude (default = 0).
• ``` init(_:) ```

Returns a GeographicCoordinates object.

#### Declaration

Swift

``public init(_ location: CLLocation)``

#### Parameters

 ``` location ``` a CLLocation object
• ``` globeDistance(to:) ```

High accuracy computation of the distance between two points on Earth’s surface, taking into account the Earth flattening.

#### Declaration

Swift

``public func globeDistance(to otherCoordinates: GeographicCoordinates) -> Meter``

#### Parameters

 ``` otherCoordinates ``` The coordinates of the second point.

#### Return Value

The distance, in meters, between the two points, along Earth’s surface.

• ``` globeRadiusOfCurvature ```

Returns the radius of the curvature of the Earth’s meridian See AA p.82-83 Symbol: Rm

#### Declaration

Swift

``public var globeRadiusOfCurvature: Meter { get }``
• ``` globeRadiusOfParallelOfLatitude ```

Returns the radius of the circle made at a constant latitude Uses the Earth ellipsoid as defined by IAU in 1976. See AA p.82-83. Symbol: Rp

#### Declaration

Swift

``public var globeRadiusOfParallelOfLatitude: Meter { get }``
• ``` rhoSinThetaPrime(forObserverHeight:) ```

Note: rho is the observer’s distance to center of the Earth (for an equatorial radius set to unity). Theta (or phi) prime is the geocentric (not geographic) latitude. See AA p.81

#### Declaration

Swift

``public func rhoSinThetaPrime(forObserverHeight height: Double) -> Double``
• ``` rhoCosThetaPrime(forObserverHeight:) ```

Note: rho is the observer’s distance to center of the Earth (for an equatorial radius set to unity). Theta (or phi) prime is the geocentric (not geographic) latitude. See AA p.81

#### Declaration

Swift

``public func rhoCosThetaPrime(forObserverHeight height: Double) -> Double``