---
title: "init(bitPattern:)"
framework: swift
role: symbol
role_heading: Initializer
path: "swift/double/init(bitpattern:)"
---

# init(bitPattern:)

Creates a new value with the given bit pattern.

## Declaration

```swift
init(bitPattern: UInt64)
```

## Parameters

- `bitPattern`: The integer encoding of a Double instance.

## Discussion

Discussion The value passed as bitPattern is interpreted in the binary interchange format defined by the IEEE 754 specification.

## See Also

### Working with Binary Representation

- [bitPattern](swift/double/bitpattern.md)
- [significandBitPattern](swift/double/significandbitpattern.md)
- [significandWidth](swift/double/significandwidth.md)
- [exponentBitPattern](swift/double/exponentbitpattern.md)
- [significandBitCount](swift/double/significandbitcount.md)
- [exponentBitCount](swift/double/exponentbitcount.md)
- [radix](swift/double/radix.md)
- [init(sign:exponentBitPattern:significandBitPattern:)](swift/double/init(sign:exponentbitpattern:significandbitpattern:).md)
- [init(nan:signaling:)](swift/double/init(nan:signaling:).md)
- [Double.Exponent](swift/double/exponent-swift.typealias.md)
- [Double.RawSignificand](swift/double/rawsignificand.md)
- [Double.RawExponent](swift/double/rawexponent.md)