# polyder

Returns the coefficients of the derivative of the polynomial whose coefficients are
given by the vector `x`.

## Syntax

polyder(x)

R = polyder(x)

[n,d] =polyder(x,y)

## Inputs

`x,y`- Polynomial vectors.

## Outputs

- R
- Resulting coefficients.
- n
- Quotient numerator.
- d
- Quotient denominator.

## Example

Simple polyder example.

`polyder([1,2,-3])`

```
R = [Matrix] 1 x 2
2 2
```

## Example

Multi-input polyder example.

```
x = [1,2,-3]
y = [4,-3,-5]
polyder(x,y)
```

```
R = [Matrix] 1 x 4
16 15 -46 -1
```

## Example

Multi-input multi-output polyder example.

```
x = [1,2,-3]
y = [4,-3,-5]
[n,d] = polyder(x,y)
n = [Matrix] 1 x 4
0 -0.6875 0.875 -1.1875
d = [Matrix] 1 x 5
1 -1.5 -1.9375 1.875 1.5625
```

## Comments

When two polynomials are given, returns the derivative of the product x*y.
When two inputs and two outputs are given, returns the derivative of the polynomial quotient
y/x. The quotient numerator is in `n` and the denominator
in `d`.