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What is a double? - free Swift 4.2 example code and tips

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What is a double?

Paul Hudson       @twostraws

The Double data type is the standard Swift way of storing decimal numbers such as 3.1, 3.14159 and 16777216.333921. Whenever you create a variable or constant that holds a number like this, Swift automatically assumes it's a Double rather than a Float, because it has a higher precision and therefore less likely to lose valuable accuracy.

Available from iOS 7.0 – learn more in my book

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