Average Error: 0.0 → 0.0
Time: 894.0ms
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 r108016 = x;
        double r108017 = r108016 * r108016;
        double r108018 = r108016 * r108017;
        double r108019 = r108018 + r108017;
        return r108019;
}

double f(double x) {
        double r108020 = x;
        double r108021 = 3.0;
        double r108022 = pow(r108020, r108021);
        double r108023 = fma(r108020, r108020, r108022);
        return r108023;
}

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 2020083 +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)))