# rotmat2vec3d

Convert 3-D rotation matrix to rotation vector

Since R2022b

## Syntax

``rotationVector = rotmat2vec3d(rotationMatrix)``

## Description

example

````rotationVector = rotmat2vec3d(rotationMatrix)` returns an axis-angle rotation vector that corresponds to the input 3-D rotation matrix. The function uses the Rodrigues formula for the conversion.```

## Examples

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Create a matrix representing a 90-degree rotation about the Z axis.

`rotationMatrix = [0 -1 0; 1 0 0; 0 0 1];`

Find the equivalent rotation vector.

`rotationVector = rotmat2vec3d(rotationMatrix)`
```rotationVector = 1×3 0 0 1.5708 ```

## Input Arguments

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Rotation of camera, specified as a 3-by-3 matrix. You can obtain this matrix by using the `estimateExtrinsics` function.

## Output Arguments

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Rotation vector, returned as a three-element vector. The vector represents the axis of rotation in 3-D, where the magnitude corresponds to the rotation angle in radians.

Data Types: `single` | `double`

 Trucco, Emanuele, and Alessandro Verri. Introductory Techniques for 3-D Computer Vision. Upper Saddle River, NJ: Prentice Hall, 1998.