<!--
{
  "availability" : [
    "iOS: 8.0.0 -",
    "iPadOS: 8.0.0 -",
    "macCatalyst: 13.0.0 -",
    "macOS: 10.10.0 -",
    "tvOS: 9.0.0 -",
    "visionOS: 1.0.0 -",
    "watchOS: 2.0.0 -"
  ],
  "documentType" : "symbol",
  "framework" : "Swift",
  "identifier" : "/documentation/Swift/Double/init(bitPattern:)",
  "metadataVersion" : "0.1.0",
  "role" : "Initializer",
  "symbol" : {
    "kind" : "Initializer",
    "modules" : [
      "Swift"
    ],
    "preciseIdentifier" : "s:Sd10bitPatternSds6UInt64V_tcfc"
  },
  "title" : "init(bitPattern:)"
}
-->

# init(bitPattern:)

Creates a new value with the given bit pattern.

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

## Parameters

`bitPattern`

The integer encoding of a `Double` instance.

## Discussion

The value passed as `bitPattern` is interpreted in the binary interchange
format defined by the [IEEE 754 specification](http://ieeexplore.ieee.org/servlet/opac?punumber=4610933).

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)