Average Error: 0.1 → 0.0
Time: 3.4s
Precision: 64
\[x \cdot \left(y + z\right) + z \cdot 5\]
\[\mathsf{fma}\left(x, z, \mathsf{fma}\left(5, z, x \cdot y\right)\right)\]
x \cdot \left(y + z\right) + z \cdot 5
\mathsf{fma}\left(x, z, \mathsf{fma}\left(5, z, x \cdot y\right)\right)
double f(double x, double y, double z) {
        double r556465 = x;
        double r556466 = y;
        double r556467 = z;
        double r556468 = r556466 + r556467;
        double r556469 = r556465 * r556468;
        double r556470 = 5.0;
        double r556471 = r556467 * r556470;
        double r556472 = r556469 + r556471;
        return r556472;
}

double f(double x, double y, double z) {
        double r556473 = x;
        double r556474 = z;
        double r556475 = 5.0;
        double r556476 = y;
        double r556477 = r556473 * r556476;
        double r556478 = fma(r556475, r556474, r556477);
        double r556479 = fma(r556473, r556474, r556478);
        return r556479;
}

Error

Bits error versus x

Bits error versus y

Bits error versus z

Target

Original0.1
Target0.1
Herbie0.0
\[\left(x + 5\right) \cdot z + x \cdot y\]

Derivation

  1. Initial program 0.1

    \[x \cdot \left(y + z\right) + z \cdot 5\]
  2. Simplified0.1

    \[\leadsto \color{blue}{\mathsf{fma}\left(x, y + z, z \cdot 5\right)}\]
  3. Taylor expanded around 0 0.1

    \[\leadsto \color{blue}{x \cdot z + \left(5 \cdot z + x \cdot y\right)}\]
  4. Simplified0.0

    \[\leadsto \color{blue}{\mathsf{fma}\left(x, z, \mathsf{fma}\left(5, z, x \cdot y\right)\right)}\]
  5. Final simplification0.0

    \[\leadsto \mathsf{fma}\left(x, z, \mathsf{fma}\left(5, z, x \cdot y\right)\right)\]

Reproduce

herbie shell --seed 2020002 +o rules:numerics
(FPCore (x y z)
  :name "Graphics.Rendering.Plot.Render.Plot.Legend:renderLegendOutside from plot-0.2.3.4, C"
  :precision binary64

  :herbie-target
  (+ (* (+ x 5) z) (* x y))

  (+ (* x (+ y z)) (* z 5)))