Function min_frule 

pub fn min_frule<R: Float>(x: R, y: R, dx: R, dy: R) -> (R, R)

Forward rule for min.

When x == y, the tangent comes from y.

Examples

use chainrules::min_frule;

let (z, dz) = min_frule(1.0_f64, 2.0_f64, 0.25, 0.5);
assert_eq!(z, 1.0);
assert_eq!(dz, 0.25);