Average Error: 0.2 → 0.1
Time: 11.2s
Precision: 64
\[\left(x \cdot x\right) \cdot \left(3 - x \cdot 2\right)\]
↓
\[3 \cdot \left(x \cdot x\right) + \left(-2\right) \cdot {x}^{3}\]
\left(x \cdot x\right) \cdot \left(3 - x \cdot 2\right)
↓
3 \cdot \left(x \cdot x\right) + \left(-2\right) \cdot {x}^{3}
double f(double x) {
        double r649832 = x;
        double r649833 = r649832 * r649832;
        double r649834 = 3.0;
        double r649835 = 2.0;
        double r649836 = r649832 * r649835;
        double r649837 = r649834 - r649836;
        double r649838 = r649833 * r649837;
        return r649838;
}
↓
double f(double x) {
        double r649839 = 3.0;
        double r649840 = x;
        double r649841 = r649840 * r649840;
        double r649842 = r649839 * r649841;
        double r649843 = 2.0;
        double r649844 = -r649843;
        double r649845 = 3.0;
        double r649846 = pow(r649840, r649845);
        double r649847 = r649844 * r649846;
        double r649848 = r649842 + r649847;
        return r649848;
}

Error

Bits error versus x

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original0.2
Target0.2
Herbie0.1
\[x \cdot \left(x \cdot \left(3 - x \cdot 2\right)\right)\]

Derivation

  1. Initial program 0.2

    \[\left(x \cdot x\right) \cdot \left(3 - x \cdot 2\right)\]
  2. Using strategy rm

  3. Applied sub-neg0.2

    \[\leadsto \left(x \cdot x\right) \cdot \color{blue}{\left(3 + \left(-x \cdot 2\right)\right)}\]

  4. Applied distribute-lft-in0.2

    \[\leadsto \color{blue}{\left(x \cdot x\right) \cdot 3 + \left(x \cdot x\right) \cdot \left(-x \cdot 2\right)}\]

  5. Simplified0.2

    \[\leadsto \color{blue}{3 \cdot \left(x \cdot x\right)} + \left(x \cdot x\right) \cdot \left(-x \cdot 2\right)\]

  6. Simplified0.1

    \[\leadsto 3 \cdot \left(x \cdot x\right) + \color{blue}{\left(-2\right) \cdot {x}^{3}}\]

  7. Final simplification0.1

    \[\leadsto 3 \cdot \left(x \cdot x\right) + \left(-2\right) \cdot {x}^{3}\]

Reproduce

herbie shell --seed 2019208 
(FPCore (x)
  :name "Data.Spline.Key:interpolateKeys from smoothie-0.4.0.2"
  :precision binary64

  :herbie-target
  (* x (* x (- 3 (* x 2))))

  (* (* x x) (- 3 (* x 2))))