Trait num_traits::ops::mul_add::MulAdd
source · pub trait MulAdd<A = Self, B = Self> {
type Output;
// Required method
fn mul_add(self, a: A, b: B) -> Self::Output;
}Expand description
Fused multiply-add. Computes (self * a) + b with only one rounding
error, yielding a more accurate result than an unfused multiply-add.
Using mul_add can be more performant than an unfused multiply-add if
the target architecture has a dedicated fma CPU instruction.
Note that A and B are Self by default, but this is not mandatory.
Example
use std::f32;
let m = 10.0_f32;
let x = 4.0_f32;
let b = 60.0_f32;
// 100.0
let abs_difference = (m.mul_add(x, b) - (m*x + b)).abs();
assert!(abs_difference <= 100.0 * f32::EPSILON);