---
title: "init(rotationByRadians:)"
framework: foundation
role: symbol
role_heading: Initializer
path: "foundation/affinetransform/init(rotationbyradians:)"
---

# init(rotationByRadians:)

Creates an affine transformation matrix from a rotation angle.

## Declaration

```swift
init(rotationByRadians angle: CGFloat)
```

## Parameters

- `angle`: The rotation angle in radians.

## Discussion

Discussion The matrix takes the following form: [  cos α   sin α  0 ] [ -sin α   cos α  0 ] [    0       0    1 ]

## See Also

### Creating Transforms

- [init()](foundation/affinetransform/init().md)
- [init(rotationByDegrees:)](foundation/affinetransform/init(rotationbydegrees:).md)
- [init(scale:)](foundation/affinetransform/init(scale:).md)
- [init(scaleByX:byY:)](foundation/affinetransform/init(scalebyx:byy:).md)
- [init(translationByX:byY:)](foundation/affinetransform/init(translationbyx:byy:).md)
- [init(m11:m12:m21:m22:tX:tY:)](foundation/affinetransform/init(m11:m12:m21:m22:tx:ty:).md)