Average Error: 0.0 → 0.0
Time: 565.0ms
Precision: 64
\[0.0 \le x \le 2\]
\[x \cdot \left(x \cdot x\right) + x \cdot x\]
\[\mathsf{fma}\left(x, x, {x}^{3}\right)\]
x \cdot \left(x \cdot x\right) + x \cdot x
\mathsf{fma}\left(x, x, {x}^{3}\right)
double f(double x) {
        double r77722 = x;
        double r77723 = r77722 * r77722;
        double r77724 = r77722 * r77723;
        double r77725 = r77724 + r77723;
        return r77725;
}

double f(double x) {
        double r77726 = x;
        double r77727 = 3.0;
        double r77728 = pow(r77726, r77727);
        double r77729 = fma(r77726, r77726, r77728);
        return r77729;
}

Error

Bits error versus x

Target

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

Derivation

  1. Initial program 0.0

    \[x \cdot \left(x \cdot x\right) + x \cdot x\]
  2. Simplified0.0

    \[\leadsto \color{blue}{\mathsf{fma}\left(x, x, {x}^{3}\right)}\]
  3. Final simplification0.0

    \[\leadsto \mathsf{fma}\left(x, x, {x}^{3}\right)\]

Reproduce

herbie shell --seed 2020003 +o rules:numerics
(FPCore (x)
  :name "Expression 3, p15"
  :precision binary64
  :pre (<= 0.0 x 2)

  :herbie-target
  (* (* (+ 1 x) x) x)

  (+ (* x (* x x)) (* x x)))