Function cbrt_frule 

pub fn cbrt_frule<S: ScalarAd>(x: S, dx: S) -> (S, S)

Forward rule for cbrt.

Examples

use chainrules::cbrt_frule;

let (y, dy) = cbrt_frule(8.0_f64, 1.0);
assert_eq!(y, 2.0);
assert!((dy - (1.0 / 12.0)).abs() < 1e-12);