# init(angle:axis:) Creates a new quaternion with an action that’s a rotation about an axis. ``` init(angle: Float, axis: SIMD3) ``` ## Parameters `angle` The rotation angle in radians. `axis` A three-element vector that specifies the rotation axis. --- Copyright © 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)