### 4.2 Higher order numerical derivatives

— Function File: dx = deriv (f, x0)
— Function File: dx = deriv (f, x0, h)
— Function File: dx = deriv (f, x0, h, O)
— Function File: dx = deriv (f, x0, h, O, N)

> Calculate derivate of function f.

> f must be a function handle or the name of a function that takes x0 and returns a variable of equal length and orientation. x0 must be a numeric vector or scalar.

> h defines the step taken for the derivative calculation. Defaults to 1e-7.

> O defines the order of the calculation. Supported values are 2 (h^2 order) or 4 (h^4 order). Defaults to 2.

> N defines the derivative order. Defaults to the 1st derivative of the function. Can be up to the 4th derivative.

> Reference: Numerical Methods for Mathematics, Science, and Engineering by John H. Mathews.