Function ceil_frule 

pub fn ceil_frule<R: Float>(x: R, _dx: R) -> (R, R)

Forward rule for ceil.

The tangent is always zero.

Examples

use chainrules::ceil_frule;

let (y, dy) = ceil_frule(1.1_f64, 0.75);
assert_eq!(y, 2.0);
assert_eq!(dy, 0.0);