---
title: "init(rotationAxis:)"
framework: swift
role: symbol
role_heading: Initializer
path: "swift/simd3/init(rotationaxis:)"
---

# init(rotationAxis:)

Returns a new vector from a Spatial rotation axis.

## Declaration

```swift
init(rotationAxis: RotationAxis3D)
```

## Discussion

Discussion Values rounded to a representable value, if necessary. note: This function is provided as a convenience. All Spatial storage and calculations are double-precision.