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# NSSwapDouble(_:)

Swaps the bytes of a number.

```
func NSSwapDouble(_ x: NSSwappedDouble) -> NSSwappedDouble
```

## Discussion

Swaps the bytes of `x` and returns the resulting value. Bytes are swapped from each low-order position to the corresponding high-order position and vice versa. For example, if the bytes of `x` are numbered from 1 to 8, this function swaps bytes 1 and 8, bytes 2 and 7, bytes 3 and 6, and bytes 4 and 5.

## See Also

[`func NSSwapLongLong(UInt64) -> UInt64`](/documentation/Foundation/NSSwapLongLong(_:))

Swaps the bytes of a number.

[`func NSSwapFloat(NSSwappedFloat) -> NSSwappedFloat`](/documentation/Foundation/NSSwapFloat(_:))

Swaps the bytes of a number.


---

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