How to convert radians to degrees

Written by Paul Hudson    @twostraws

Most angles in iOS are measured using radians rather than degrees, but the majority of users prefer to see degrees so you’ll need to do some conversion. The equation to convert between the two is simple enough: multiply the number by 180, then divide the result by Pi.

To make things easier, drop in this function:

func rad2deg(_ number: Double) -> Double {
    return number * 180 / .pi
}

You can now use rad2deg(5) to find 5 radians in degrees.

Available from iOS 8.0

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