Function reikna::derivative::slope_at

pub fn slope_at(f: &Function, x: f64) -> f64

Estimate the value of the derivative of f at x

This function works by applying the limit definition of the derivative at x in the same way that nth_derivative() does. See the documentation for nth_derivative() for more information.

Examples

#[macro_use] extern crate reikna;
use reikna::derivative::*;

let f = func![|x| (x + 4.0) * (x + 4.0)];
println!("f'(-4.0) = {}", slope_at(&f, -4.0));

Outputs:

f'(-4.0) = 0.000001000000000279556