# Documentation

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# quat2rotm

Convert quaternion to rotation matrix

## Syntax

``rotm = quat2rotm(quat)``

## Description

example

````rotm = quat2rotm(quat)` converts a quaternion `quat` to an orthonormal rotation matrix, `rotm`. When using the rotation matrix, premultiply it with the coordinates to be rotated (as opposed to postmultiplying).```

## Examples

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```quat = [0.7071 0.7071 0 0]; rotm = quat2rotm(quat) ```
```rotm = 1.0000 0 0 0 -0.0000 -1.0000 0 1.0000 -0.0000 ```

## Input Arguments

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Unit quaternion, specified as an n-by-4 matrix containing n quaternions. Each quaternion, one per row, is of the form q = [w x y z], with w as the scalar number.

Example: `[0.7071 0.7071 0 0]`

## Output Arguments

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Rotation matrix, returned as a 3-by-3-by-n matrix containing n rotation matrices. Each rotation matrix has a size of 3-by-3 and is orthonormal. When using the rotation matrix, premultiply it with the coordinates to be rotated (as opposed to postmultiplying).

Example: `[0 0 1; 0 1 0; -1 0 0]`