How can I convert from degrees to radians?
Xcode 11 • Swift 5.1 or later
extension BinaryInteger {
var degreesToRadians: CGFloat { CGFloat(self) * .pi / 180 }
}
extension FloatingPoint {
var degreesToRadians: Self { self * .pi / 180 }
var radiansToDegrees: Self { self * 180 / .pi }
}
Playground
45.degreesToRadians // 0.7853981633974483
Int(45).degreesToRadians // 0.7853981633974483
Int8(45).degreesToRadians // 0.7853981633974483
Int16(45).degreesToRadians // 0.7853981633974483
Int32(45).degreesToRadians // 0.7853981633974483
Int64(45).degreesToRadians // 0.7853981633974483
UInt(45).degreesToRadians // 0.7853981633974483
UInt8(45).degreesToRadians // 0.7853981633974483
UInt16(45).degreesToRadians // 0.7853981633974483
UInt32(45).degreesToRadians // 0.7853981633974483
UInt64(45).degreesToRadians // 0.7853981633974483
Double(45).degreesToRadians // 0.7853981633974483
CGFloat(45).degreesToRadians // 0.7853981633974483
Float(45).degreesToRadians // 0.7853981
Float80(45).degreesToRadians // 0.78539816339744830963
If you would like to make the binary integer return a floating point type instead of always returning a CGFloat you can make a generic method instead of a computed property:
extension BinaryInteger {
func degreesToRadians<F: FloatingPoint>() -> F { F(self) * .pi / 180 }
}
let radiansDouble: Double = 45.degreesToRadians() // 0.7853981633974483
let radiansCGFloat: CGFloat = 45.degreesToRadians() // 0.7853981633974483
let radiansFloat: Float = 45.degreesToRadians() // 0.7853981
let radiansFloat80: Float80 = 45.degreesToRadians() // 0.78539816339744830963
This is not identically what you asked, but in Swift 3 / iOS 10, you can use the Measurement type and do the conversion without knowing the formula!
let result = Measurement(value: 45, unit: UnitAngle.degrees)
.converted(to: .radians).value