---
title: "GLKQuaternionAngle(_:)"
framework: GLKit
role: symbol
role_heading: Function
platforms: [iOS 5.0+, iPadOS 5.0+, macOS 10.8+, tvOS 9.0+]
path: "glkit/glkquaternionangle(_:)"
---

# GLKQuaternionAngle(_:)

Returns the rotation angle of a quaternion.

## Declaration

```swift
func GLKQuaternionAngle(_ quaternion: GLKQuaternion) -> Float
```

## Parameters

- `quaternion`: A quaternion.

## Return Value

Return Value The angle of the rotation in radians (a positive angle is counterclockwise).

## See Also

### Retrieving Information About a Quaternion

- [GLKQuaternionLength(_:)](glkit/glkquaternionlength(_:).md)
- [GLKQuaternionAxis(_:)](glkit/glkquaternionaxis(_:).md)