 			self = FloatQuaternion(angle: newValue, axis: existingAxis)
 		}
 	}
+	@available(macOS 10.12, iOS 10.10, tvOS 10.10, *)
+	public var angleMeasurement:Measurement<UnitAngle> {
+		get { return Measurement<UnitAngle>(value: Double(self.angle), unit: .radians) }
+		set {
+			let angleRadiansMeasurement = newValue.converted(to: .radians)
+			self.angle = Float(angleRadiansMeasurement.value)
+		}
+	}
 	
 	public var axis:Float3 {
 		get { return Float3(simd_axis(self.simdValue)) }

	public init(angle angle_radians:Float, axis:Float3) {
		self = FloatQuaternion(simd_quaternion(angle_radians, axis.simdValue))
	}
	
	public var angle:Float {
		get { return simd_angle(self.simdValue) }

	
	public var angleAxis:(Float, Float3) {
		get { return ( self.angle, self.axis ) }
		set { self = FloatQuaternion(angle: newValue.0, axis: newValue.1) }
	}
	@available(macOS 10.12, iOS 10.10, tvOS 10.10, *)
	public var angleMeasurementAxis:(Measurement<UnitAngle>, Float3) {
		get { return ( self.angleMeasurement, self.axis ) }
		set { self = FloatQuaternion(angle: newValue.0, axis: newValue.1) }
	}
	
