# roots

Find polynomial roots.

## Syntax

* r = roots(p)

## Input argument

* p - vector: polynomial coefficients

## Output argument

* r - roots

## Description

**r = roots(c)** finds the roots of the polynomial **c**. **r** is a column vector.

This function uses the companion matrix of the polynomial to find the roots.

## Example

```matlab
p = [1 0 0 0 -1];
r = roots(p)
```

## See also

[poly](poly).

## History

| Version | Description     |
| ------- | --------------- |
| 1.0.0   | initial version |

## Author

Allan CORNET
